COMPARISON OF THE PREVALENCE OF RISK FACTORS FOR STEMI AMONG THE YOUNG AND OLD FROM
VELLORE AND SURROUNDING DISTRICTS
DISSERTATION SUBMITTED TOWARDS FULFILLMENT OF THE RULES AND REGULATIONS FOR THE MD GENERAL MEDICINE
EXAMINATION OF THE TAMIL NADU DR. M.G.R. MEDICAL UNIVERSITY TO BE HELD IN MAY2020
Registration Number: 201711459
COMPARISON OF THE PREVALENCE OF RISK FACTORS FOR STEMI AMONG THE YOUNG AND OLD FROM
VELLORE AND SURROUNDING DISTRICTS
Dr K Lalmuanzuala
Registration Number : 201711459 Department of General Medicine Christian Medical College
Vellore October 2019
BONAFIDE CERTIFICATE
This is to certify that the dissertation entitled “Comparison of the prevalence of risk
factors for STEMI among the young and old from Vellore and surrounding districts”
is a bona fide original work done by Dr. K Lalmuanzuala during his academic term
April 2017 to March 2020, at Christian Medical College, Vellore as per Christian
Medical College rules for thesis for the department of General Medicine for
examination of the Tamil Nadu Dr.M.G.R. Medical University, Chennai to be held in
May 2020.
Dr Thambu David Sudarsanam Head of the department
Department of General Medicine Christian Medical College
Vellore
BONAFIDE CERTIFICATE
This is to certify that the dissertation entitled “Comparison of the prevalence of risk
factors for STEMI among the young and old from Vellore and surrounding districts”
is a bona fide original work done by Dr. K Lalmuanzuala during his academic term
April 2017 to march 2020, at Christian Medical College, Vellore as per Christian
Medical College rules for thesis for the department of General Medicine for
examination of the Tamil Nadu Dr.M.G.R. Medical University, Chennai to be held in
May 2020.
Dr O.C Abraham Professor
Department of General Medicine Christian Medical College
Vellore
BONAFIDE CERTIFICATE
This is to certify that the dissertation entitled “Comparison of the prevalence of risk
factors for STEMI among the young and old from Vellore and surrounding district” is
a bona fide original work done by Dr. K Lalmuanzuala during his academic term
April 2017 to march 2020, at Christian Medical College, Vellore as per Christian
Medical College rules for thesis for the department of General Medicine for
examination of the Tamil Nadu Dr.M.G.R. Medical University, Chennai to be held in
May 2020.
Dr Anna B Pulimood The Principal
Christian Medical College Vellore
DECLARATION
This is to certify that this dissertation titled ““Comparison of the prevalence of risk factors for STEMI among the young and old from Vellore and surrounding district”” which is submitted by me towards partial fulfillment of rules and regulations for M.D. General Medicine Examination of the Tamil Nadu Dr. M.G.R. University, Chennai to be held in May 2020 comprises of original work done by me. The information taken from other sources has been duly acknowledged and cited.
Dr. Lalmuanzuala Post Graduate Student
Registration Number: 201711459 Department of General Medicine
Christian Medical College, Vellore – 04
ANTIPLAGIARISM CERTIFICATE
Dr O.C Abraham Professor
Department of General Medicine Christian Medical College
Vellore
ACKNOWLEDGEMENTS
I express my deep gratitude to the people who were involved in this dissertation from its conceptualization till the completion.
Firstly, to God who gave me the opportunity to join Medicine as my profession.
I express my sincere gratitude to my guide Dr O.C Abraham, Professor of General Medicine and Dr Ronald Carey who has been a constant source of support, for correcting my thesis and for the continuous encouragement.
I am grateful to the Department of General medicine and my teachers who have taught Me, inparticular Dr. Sowmya Satyendra and Dr Thambu David who have guided me in various ways.
I also extend my gratitude to Cardiology Department for allowing me to recruit patientsfrom acute chest pain unit. Special thanks to Dr. Oommen George and Dr.
Anoop George Alex.
I am grateful to Miss. Mahasampath Gowri, Biostatistics department, for her valuable contribution.
I am extremely grateful to Sister Gloria from Cardiology and my intern Dr Jerome Nirmal for their help in my dissertation.
Finally, I am indebted to to all the patients who consented to take part in the study without whom the study would not have been possible.
Contents
INTRODUCTION ... 12
AIMS AND OBJECTIVES ... 15
LITERATURE REVIEW ... 17
ISCHAEMIC HEART DISEASE - DEFINITION ... 18
ACUTE CORONARY SYNDROME – ... 21
PATHOPHYSIOLOGY OF MYOCARDIAL ISCHAEMIA- ... 21
RISK FACTORS – ... 32
MATERIAL AND METHODS ... 50
METHODS ... 51
RESULTS ... 70
DISCUSSION : ... 87
CONCLUSIONS ... 99
STRENGTH: ... 102
LIMITATIONS ... 104
ANNEXURE 1 :BIBLIOGRAPHY ... 106
ANNEXURE 2 : IRB APPROVAL FORM ... 113
ANNEXURE 3 : INFORMATION SHEET AND CONSENT FORMS ... 119
ANNEXURE 4: CLINICAL RESEARCH FORM ... 126
ANNEXURE 5: DATA SHEET ... 131
ANNEXURE 6: ABSTRACT ... 134
LIST OF ABBREVIATIONS:
1. ACS – ACUTE CORONARY SYNDROME
2. STEMI - ST ELEVATION MYOCARDIAL INFARCTION
3. NSTEMI - NON ST-ELEVATION MYOCARDIAL INFARCTION 4. NSTE – ACS – NON ST SEGMENT ELEVATION MYOCARDIAL
INFARCTION.
5. UA – UNSTABLE ANGINA 6. ECG – ELECTROCARDIOGRAM 7. LDL – LOW DENSITY LIPOPROTEIN 8. HDL- HIGH DENSITY LIPOPROTEIN
9. ACE – ANGIOTENSIN CONVERTING ENZYME 10. ARB’s – ANGIOTENSIN RECEPTOR BLOCKER
11. TIMI – THROMBOLYSIS IN MYOCARDIAL INFARCTION 12. BMI – BODY MASS INDEX
13. OSA – OBSTRUCTIVE SLEEP APNEA
14. LVH – LEFT VENTRICULAR HYPERTROPHY 15. LAD – LEFT ANTERIOR DESCENDING
TABLE OF TABLES
Table 1.BASELINE CHARACTER
Table 2.BASELINE CHARACTER AMONG THE YOUNG Table 3.BASELINE CHARACTER AMONG THE OLD Table 4.LDL LEVEL WITH STEMI
Table 5.LDL LEVEL WITH STEMI Table 6.HDL LEVEL AND STEMI
Table 7.TRIGLYCERIDE LEVEL AND STEMI Table 8.ABDOMINAL OBESITY AND STEMI Table 9.BMI AND STEMI
Table 10.DIABETES MELLITUS WITH STEMI Table 11.SMOKING WITH STEMI
Table 12.HYPERTENSION WITH STEMI
Table13.HOMOCYSTEINE LEVEL WITH STEMI Table 14.ALCOHOL INTAKE WITH STEMI
Table 15.FAMILY HISTORY OF SUDDEN DEATH WITH STEMI Table 16.POOR DIETARY PATTERN WITH STEMI
Table 17.LACK OF EXERCISE/INADEQUATE PHYSICAL ACTIVITY WITH STEMI
Table 18.PSYCHOSOCIAL STRESS WITH STEMI Table 19.GENDER DIFFERENCE WITH STEMI
TABLE OF FIGURES
Figure 1: MACRO AND MICRO CIRCULATION ACROSS SEGMENT AND SIZES OF THE ARTERIES.
Figure 2 : CASCADE OF MECHANISMS AND MANIFESTATION OF ISCHAEMIA.
FIGURE 3: REPERFUSION THERAPY FOR PATIENTS WITH STEMI FIGURE 4: GENDER DIFFERERENCE IN BOTH GROUP
INTRODUCTION
Ischemic heart disease is a life threatening disease that is associated with significant mortality and morbidity. In India, there has been an alarming rise in the prevalence of IHD. A number of studies have shown that the Indian population is a higher risk of developing Ischemic heart disease when compared to people of other ethnicities in the same age group. However, the risk factors for acute coronary syndrome noted elsewhere were not similar among the young and the old. We did this study to compare the risk factors between the young and old patients with a diagnosis of STEMI from Vellore and surrounding districts.
AIMS AND OBJECTIVES
AIMS – To delineate the common risk factors for STEMI among the young patients who present with ST elevation MI .
Primary objectives:
1. To find the prevalence of common cardiovascular risk factors in young people with ST elevation MI.
2. Compare the prevalence of the risk factors with the older patients who present with STEMI.
LITERATURE REVIEW
ISCHAEMIC HEART DISEASE - DEFINITION
Ischemic heart disease (IHD) is a clinical condition in which there is an inadequate
supply of blood and oxygen to a portion of the myocardium. It typically occurs when
there is an imbalance between myocardial oxygen supply and demand.
The most common cause of ischaemia of myocardium is atherosclerotic disease of an
epicardial coronary artery (or arteries). The ischaemia occurs when the
atherosclerosis is sufficient enough to cause a regional reduction in myocardial blood
flow causing inadequate perfusion of the myocardium supplied by the involved
coronary artery.
ACUTE CORONARY SYNDROME – EPIDEMIOLOGY
Cardiovascular disease is the most common cause for total years of life lost worldwide
according to LANCET systemic analysis for global burden of disease 2016(1).
Globally, Cardiovascular disease led to 17.5 million deaths in 2012and more
than 75% of these deaths occurred in developing countries(1 , 2). In GRACE study
(Global registry of acute coronary events), the prevalence of young acute coronary
syndrome (ACS) was 6.3% and in the Thigh ACS Registry, it was 5.8% and in
Spain Registry, it was 7%(3,4,5).
In India more than 10.5 million deaths occur annually due to cardiovascular
disease, and it was reported that cardiovascular disease led to 16.9% of all deaths in
women and 20.3% among the men(2).
The prevalence of coronary heart disease according to India Migration Study was
1.45%, India Heart Watch 2.55%and PURE 2.04%(6,7, 8).A risk factor study in
Kerala reported known coronary heart disease in 1.7%(9) and a multisite study in
Kerala reported definite CHD in 3.5%(10). Thus, known coronary heart disease in
these studies vary from 2%-4%, and this may be a more realistic prevalence of CHD
in the general population in India(11).
In India, according to the global study of disease burden in 1990-2016the five
leading cause of loss of Disability adjusted life years were Ischemic heart disease,
chronic obstructive pulmonary disease, diarrheal illness, lower respiratory tract
infection(LRTI) and cerebrovascular accident(12). Coronary artery disease remains
and will be the major cause of mortality and morbidity worldwide in the near future.
Identification of risk factors that predispose to cardiovascular disease is necessary.
While worldwide many risk factors have been identified and has been targeted in
treatment, it is essential to find risk factors that are unique to geographical locations
and in different age groups to successfully reduce the adverse events of this disease.
ACUTE CORONARY SYNDROME
Patients with acute coronary syndrome (ACS) are commonly classified into two
groups to facilitate evaluation and management. They are patients with acute
myocardial infarction with ST-segment elevation (STEMI) based on their presenting
ECG and those with non-ST-segment elevation acute coronary syndrome (NSTE-
ACS)(13).
NSTE – ACS include patients with non-ST-segment elevation myocardial infarction
(NSTEMI) and by definition have evidence of myocyte necrosis, and those with
unstable angina (UA), who do not have evidence of myocyte necrosis.
PATHOPHYSIOLOGY OF MYOCARDIAL ISCHAEMIA-
The concept of myocardial supply and demand is central to understand the
pathophysiology of myocardial ischaemia. Under normal conditions, for any level of
demand for oxygen, the myocardium will be able to control the supply of oxygen-rich
blood to prevent myocytes underperfusion and subsequently the development of
ischemia and infarction(13). The major determinants of myocardial oxygen demand
are heart rate, contractility of myocardium, and myocardial wall tension (stress).
An adequate myocardial oxygen supply requires a satisfactory level of oxygen–
carrying capacity of the blood and an adequate level of coronary blood flow. Majority
of blood flow through the coronary artery occur during diastole.
About75% of total coronary resistance to flow occur across three sets of arteries: (1)
large epicardial arteries ( R1), (2) prearteriolar vessels (R2), and (3) arteriolar and
intramyocardial capillary vessels (R3). R1 is of minimal significance in the absence of
significant flow-limiting atherosclerotic obstructions. The major determinant of
coronary resistance is found in R2 and R3.
FIGURE 1 : MACRO AND MICRO CIRCULATION ACROSS SEGMENTS AND
SIZES OF THE ARTERIES.(Modified from B De Bruyne et al: J Am CollCardiol
67:1170, 2016.)
The normal coronary circulation is controlled and dominated by the heart’s
requirements for oxygen. Normally, the intramyocardial resistance vessels
demonstrate a great capacity for dilation(both R2 and R3 decrease). The coronary
resistance vessels can also adapt to physiologic alterations in blood pressure to
maintain coronary blood flow at levels appropriate to the need of myocardium
(autoregulation).
By reducing the lumen of the artery of coronaries, atherosclerosis limits appropriate
increase in perfusion of the myocardium when the demand for flow is augmented.
When the luminal reduction is severe enough, myocardial perfusion in the basal state
is reduced. Spasm as in Prinzmetal’s angina, arterial thrombi, rarely coronary emboli
as well as aortitis causing ostial narrowing can limit coronary blood flow.
In infancy congenital abnormalities such as the origin of the left anterior descending
coronary artery (LAD) from the pulmonary artery may cause myocardial ischemia and
infarction, but is very rare in adults.
Ischemia of myocardium also can occur if myocardial oxygen demands are markedly
increased, particularly when coronary blood flow may be limited, as in aortic stenosis
causing severe left ventricular hypertrophy (LVH). Ischaemia can also occur when
there is abnormal constriction or failure of normal dilation of the coronary resistance
vessels also can cause ischemia. When this condition causes angina, it is referred to as
microvascular angina.
CORONARY ATHEROSCLEROSIS –
The major site of atherosclerotic disease is the epicardial coronary arteries. The major
risk factors for atherosclerosis like high levels of plasma low-density lipoprotein
[LDL], low plasma HDL, cigarette smoking, hypertension, and diabetes mellitus vary
in their impact (relative) on disturbing the normal functions of the vascular
endothelium(13).
The functions of the risk factors include local control of vascular tone, maintenance
of antithrombotic surface, control of inflammatory cell adhesion and diapedesis.
The loss of the defence mechanism leads to inappropriate constriction, formation of
luminal thrombus, and abnormal interactions between blood cells and the activated
vascular endothelium . Atherosclerotic plaque i.e the subintimal collections of fat,
smooth muscle cells, fibroblasts, and intercellular matrix result from functional
changes in the vascular milieu.
The combination of vulnerable vessel in a patient with vulnerable blood promotes a
state of hypercoagulability and hypofibrinolysis which is especially true in patients
with diabetes mellitus.
There is a predilection for atherosclerotic plaques to develop at increased turbulence
sites in coronary flow, such as the branch points in the epicardial arteries.
Limitation of the ability to increase flow to meet the increased myocardial demand is
noted when a stenosis reduces the diameter of an epicardial artery by 50%.When the
diameter of epicardial artery is further reduced by ~80%, the blood flow at rest may be
reduced. A further decrease in the stenotic orifice area can further reduce coronary
flow significantly to cause myocardial ischemia at rest or with minimal stress.
The abrupt development of severe ischemia, as in total or subtotal coronary occlusion,
is mostly associated with instantaneous failure of normal muscle relaxation and then
contraction. The severity and duration of the imbalance between myocardial oxygen
supply and demand determine whether the damage is reversible or permanent, with
subsequent myocardial necrosis.
Ischemia causes characteristic changes in the ECG such as repolarization
abnormalities, as evidenced by inversion of T waves and, when more severe,
displacement of ST segments. Non transmural, intramyocardial ischaemia is probably
reflected on ECG as transient T wave inversion. Transient ST-segment depression
often reflects patchy subendocardial ischemia and more severe transmural ischaemia
can manifest as ST- segment elevation.
Figure 2 –CASCADE OF MECHANISMS AND MANIFESTATION OF ISCHAEMIA.
PATHOPHYSIOLOGY: ROLE OF ACUTE PLAQUE RUPTURE –
STEMI usually occurs when thrombotic occlusion of a coronary artery causes the
coronary blood flow to decrease abruptly which was previously affected by
atherosclerosis. Histologic studies indicate that the coronary plaques with a rich lipid
core and a thin fibrous cap are prone to disruption. A gradually developing high-grade
coronary artery stenoses do not typically precipitate STEMI because of the rich
collateral network development over time. STEMI instead occurs when a coronary
artery thrombus develops at a site of vascular injury rapidly. Cigarette smoking,
hypertension and lipid accumulation produces or facilitates this injury.
STEMI, in most cases, occurs when the surface of an atherosclerotic plaque becomes
disrupted, exposing its contents to the blood and when local or systemic conditions
favour thrombogenesis. A mural thrombus is formed at the site of plaque disruption
and the involved coronary artery becomes occluded.
After an initial monolayer of platelets formed at the site of the disrupted plaque,
various agonists like ADP, collagen, epinephrine and serotonin promote platelet
activation. After platelet stimulation a potent local vasoconstrictor, Thromboxane A2
is released and a further activation of platelet occur and a potential resistance to
fibrinolysis developed. Agonist also cause conformational change in glycoprotein
2b/3a receptor. This receptor once converted to its functional state develops a high
affinity for soluble adhesive proteins (integrins) such as fibrinogen. Fibrinogen can
bind to two different platelets simultaneously resulting in platelet cross linking and
aggregation.
On exposure to tissue factor, the coagulation cascade is finally activated.A thrombus
containing platelet aggregates and fibrin strand finally occluded the culprit coronary
artery.
STEMI in rare cases may be due to coronary artery occlusion caused by congenital
abnormalities, coronary emboli, coronary spasm and a wide variety of systemic illness
particularly inflammatory diseases.
RISK FACTORS –
RISK FACTOR PROFILES FOR ACUTE CORONARY SYNDROME IN ASIA
One of the large studies which looks at the clinical profile of young patient with acute
myocardial infarction in Asia was done in Singapore Wong et al Singapore(14). They
investigated the clinical features and in-hospital outcomes in young adults between Jan
2005 and September 2017. The study recruited 333 consecutive patients under 45 years of
age with acute Myocardial Infarction of different ethnicity. In this study, signs and
symptoms, blood investigation ,angiography findings and in hospital clinical outcome were
observed. The mean age of presentation was 40.2 years. Majority of the cases were Chinese
followed by Indians and then Malaysians. Risk factors among them were smoking (74%),
Obesity (37%), hypertension (28.5%) and hyperlipidaemia (20%). Single vessel disease
involvement was seen in 46%. This study showed that Indians have 3 fold risk of developing
premature Myocardial infarction when compared to other ethnic groups. This study also
showed that the percentage of double and triple vessel disease was 26 and 23.4 %
respectively.
In another study done in Singapore which compared MI events and mortality rates
among different ethnic groups residing in Singapore(15). It was found that Chinese patients
were mostly older comparing to other ethnic groups and less likely to have typical
symptoms of MI or previous MI. Compared with Chinese, MI event rates were more
than 2-fold and more than 3-fold higher for Malays and Indians respectively. Age-
standardized coronary mortality rates were 2.4 higher for Malays and 3.0 higher times
for Indians. This study again shows that Indians have the greatest MI event rates compared to
other ethnic groups.
A cross-sectional study was done by Ranjith et al to look at the prevalence and risk factors
for ACS in a subgroup of young Indian population residing in South Africa with
age less than or equal to 45 years presenting to the coronary care unit at RK Khan
hospital in Durban(16). This study showed that out of 245 patients ,74% had a history of
smoking, 54% had hypertryglyceridaemia and only 14% were women .There was
involvement of single vessel in 28%, double vessel in 20% and triple vessel in 52%. .
Abnormal HDL cholesterol level were detected in 43% and 9% among male and female.
There was a strong familial link as 54% had a family background of Coronary heart
disease.
Malaysian national cardiovascular disease registry March 2006 – February 2010 (17)
showed that among patients with Acute coronary syndrome Malays had a higher BMI
comparing to ethnicity while Chinese had highest rate of hypertension and
hyperlipidemia. Indians had higher rate of Diabetes Mellitus and family history of
coronary heart disease.
RISK FACTOR PROFILES IN INDIA-
The cardiovascular risk factors in the young patients have been studied by other researchers
in India. Kumar et al looked at Apoprotein E gene polymorphism in patients with
premature myocardial infarction and their relation to serum lipid level in patients aged below
40 years with myocardial infarction compared with those more than45 years of age(18).
The study showed that higher frequencies of apo E4 alleles, genotypes E3/E4, E4/E4 were
recorded in the premature MI group compared with the controls. Multivariate regression
analysis showed that E4 alleles were at 46 times higher odds to develop premature MI
compared with individuals without E4 allele. This study also showed that among the risk
factors for acute coronary events, dyslipidaemia and high waist hip ratio were the most
significant.
Another study conducted in North India looked at the cardiovascular risk factors in
young patients with coronary artery disease(19). They had recruited 79 patients between Jan
2000- Dec 2001 and 83 patients between Jan 2009 and Dec 2010. Among women –
hypertension, dysglycemia, family history, metabolic syndrome, high LDL and high waist
size were the common risk factors while in men dysglycemia, positive family history and
higher waist size were statistically significant. This study concluded that metabolic syndrome,
dysglycemia and high LDL were a significant risk factors among the young.
A prospective cohort study done in India by Agrawal et al, looked at the clinical
profile and angiographic correlation in patients with naïve acute coronary syndrome(20). The
study showed that the mean age of presentation was 58.9 years with 27% below 50 years.
Among them 75% were male and 65% had STEMI. Factors favouring triple vessel disease
include female sex, higher age, smoking, Diabetes Mellitus and NSTEMI. Among STEMI,
the risk factors noticed were Diabetes mellitus (23%), Hypertension (21%), Smoking (16%),
family history(11%) and BMI> 30 (21%). The mean LDL was 115 mg/dl while mean HDL
was 39 mg/dl.
A comparison study looking at genetic polymorphism, biochemical factors and conventional
risk factors in young and elderly north Indian patients with acute myocardial infarction was
done by Kaur et al(21). In his study 184 young and 166 elderly north Indians with Acute
myocardial infarction were included in the study. This study showed that genetic
polymorphism such as Factor 5 laden, factor 7, platelet membrane glycoprotein and MTHR
were equally prevalent in young and elderly patients. Multiple logistic regression analysis
showed that smoking(p<0.001) and hyperhomocysteinemia (0.001) were the significant risk
factors among the young.
A study on homocysteine levels with MTHFR polymorphism in young patients with
acute myocardial infarction was done by Eftychiouwhere 63 male patients with ACS
and 56 controls without coronary artery disease were included in the study(22). This
study showed that higher levels of homocysteine are associated with acute myocardial
infarction and multi-vessel disease in patients under the age of 50. Existence and extend
of disease are not associated with MTHFR polymorphism. This study also showed that
lower HDL is associated with higher levels of homocysteine.
Another study from India looked at serum lipid level and metabolic syndrome and 492
patients with age less than 45 years were included in the study(23). This study showed that
65%(295) according to IDF criteria and 61%(301) according to NCEP ATP 3 satisfied the
criteria for metabolic syndrome among patients who presented with acute myocardial
infarction.
A study on Lipoprotein a and Apo E polymorphism in young patients of south African
Indians with myocardial Infarction was conducted where 195 young South African Indians
patients with Acute MI under 45 years were taken into the study(24). This study showed that
Apo E3/E4 genotype is strongly associated with the incidence of myocardial Infarction in
young South African Indians also LDL and HLC levels. However, pentanucleotide repeat
polymorphism does not appear to have any aetiological role in Myocardial Infarction.
A study which was done in North India by Tewari showed that there was difference in
clinical, biochemical and angiographic profile of young patients vs older patients in
angiographically proven atherosclerotic coronary artery disease(25). In this study 825
patients were in Group 1 – age more than 55 years, 924 patients in group 2-age 41-55
years of age, 219 in group 3 – patients below or equal to 40 years of age. This study
showed that Diabetes Mellitus and Hypertension was more common in the older cohort
while smoking was more common in the younger cohort. The younger cohort also had more
atherogenic lipid profile, higher prevalence of smoking and single vessel disease. This
study concluded that total cholesterol/HDL ratio was a better predictor of Coronary
artery disease when compared to individual lipid level.
Amity study was a study done in Uttar Pradesh ,where a total of 1,116 consecutive patients
with STEMI aged less than or equal to 30 were studied between March 2013 and February
2015 for risk factors, clinical presentation, angiographic profile including severity and in –
hospital outcome with first acute myocardial infarction(26). The study showed that a mean
age of the patient was 26.3 years and common risk factor include smoking, family history of
premature coronary artery disease, obesity, physical inactivity and stressful life events. The
most common symptoms was chest pain and the most common presentation was AWMI.
Majority of the patients had single vessel involvement with LAD being the most common
culprit vessel.
Another prospective cohort study of 100 patients admitted with acute coronary
syndrome in Purvanchal area of Uttar Pradesh showed that diabetes mellitus,
hypertension, smoking and family history of cardiovascular disease were the main risk
factor for acute coronary syndrome(27). The study also concluded that female sex,
higher age, smoking, presence of diabetes mellitus and NSTEMI were the factors
favouring triple vessel disease.
A study done in a tertiary centre - Thanjavur Medical college South India evaluated the demographic features, cardiovascular risk factors, clinical presentation, serial ECG findings and 2D Echo features from 236 patients admitted with Acute STEMI(28).
The study showed that the majority of the patients were male and the commonly affected age group was 40 – 60 years. The study showed that the proportion of female patients with STEMI increased with advancing age. Among the risk factors type 2 Diabetes mellitus was the most common modifiable risk factor. Smoking and
alcoholism contributed as significant risk factors for males. Chest pain was the most common presenting symptoms and majority of patients had anterior wall MI.
Bharadwaj et all evaluate the risk factor for STEMI among the young. The study
showed that Myocardial Infarction in age less than 40 years of age is almost seen
exclusively in male(29). The major risk factors include smoking, hypertension, high
triglycerides, low HDL and raised Lpa. Most patients have anterior wall MI and most
have single vessel disease. The in hospital mortality was low.
Elevated homocysteine level is a common risk factor among Indians compared
With any other ethnicity group(30). The elevated homocysteine concentration could
be explained by lower vitamin B12 and folate level due to our diet.
Premature coronary artery disease in India : CADY registry recruited 997 young
patient presenting with acute coronary syndrome or stable Ischaemic heart
disease(men < 55 and women <65 years) from 22 centres across India(31). The study
showed that the mean age of participants was 49.1 years and majority were men. The
risk factors noted were family history of coronary artery disease, Diabetes mellitus,
hypertension, dyslipidaemia, smoking/tobacco use, sedentary habits and possible
familial hypercholesterolemia. Metabolic risk factors were significantly greater among
women. Women presented more commonly with Non STE- ACS and they were older
at time of diagnosis of ACS.
Kerela ACS registry prospectively collected date on 25,748 consecutive
admissions in 125 hospitals from 2007 to 2009 in Kerala(32). They evaluated data on
presentation, management and in hospital mortality and major adverse cardiovascular
events (MACE). The mean age at presentation was 60 years and it did not differ
among ACS types. The major risk factors were Diabetes Mellitus, hypertension and
smoking..
The Chennai Urban population study (CUPS) 2001 was an epidemiological study
involving two areas in Chennai, South India(33). The overall prevalence rate of CAD
was 11% ( age standardized, 9%). The prevalence of CAD were 9.1%, 14.9% and
21.4%in those with normal glucose tolerance, impaired glucose tolerance and
Diabetes mellitus respectively. The prevalence of CAD increased with an increase in
totalcholesterol, LDL cholesterol and Triglycerides and total cholesterol / high density
lipoprotein ratio. Multiple logistic regression analysis identified age and LDL
cholesterol as the main risk factors for Acute coronary syndrome. A well - established
risk factor - smoking - had no association with CAD in this study.
Joshi et al compare the risk factors for early myocardial infarction in south
Asians comparing with individuals in other countries(34). The main risk factors which
showed a significant association across all south Asian countries were current and
former smoking, high ApoB100/Apo-1 ratio, history of hypertension, Diabetes
mellitus.
Alcohol consumption was not protective in native South Asians(34). This may be
related to lower prevalence or patterns of drinking ( binge drinking in South Asians vs
regular drinking in other countries). Consumption of green leafy vegetables and fruits
were associated with lower risk of ACS.
A study in Tertiary centre from North east India recruited 704 patients with acute
coronary syndrome(35). 72.4% presented with STEMI, 27.6% presented with
NSTEMI/UA. Males outnumbered females in STEMI while both sexes were almost
equal among NSTEMI/UA. The mean age of presentation was 56.5 years. The mean
age of NSTEMI/UA was higher than STEMI. The main risk factors noted were
smoking, hypertension, Diabetes Mellitus and grade 1 obesity.
CREATE was a prospective registry in 89 centres from 10 regions and 50 cities
across India(36). They enrolled 20, 937 patients in their study. The mean age was 57.5
years and patients with STEMI were younger when compared with NSTEMI or
unstable angina. Most of the patients were from lower middle and lower
socioeconomic status. The major risk factors are Diabetes mellitus, hypertension and
smoking.
Mahalle et all studied 300 patients with angiography proven Coronary disease(30).
This study showed that hyperhomocysteinemia was present in 95.3%. They also
Noticed that low B12 level and and elevated homocysteine were significantly higher
among patients with dyslipidaemia, Diabetes Mellitus and hypertension. Serum B12
level was inversely associated with Triglycerides and VLDL, and positively with
HDL. Vitamin B12 was inversely correlated with inflammatory markers, directly
Related to Insulin resistance whereas homocysteine showed the opposite pattern.
Most the risk factors identified in different studies were modifiable except family
history. Among the studies which compared different ethnic groups, Indians are more
prone to develop acute coronary syndrome and at an earlier age. Our study was done
done to provide better knowledge, data and understanding regarding the risk factors in
people residing in and around Vellore. This should help in developing screening
programs, early identification of risk factors and thereby reduce the morbidity and
mortality due to IHD.
MANAGEMENT OF STEMI-
FIGURE – REPERFUSION THERAPY FOR PATIENTS WITH STEMI
Aspirin is effective across the entire spectrum of acute coronary syndrome - STEMI,
NSTEMI/UA. Rapid inhibition of COX-1 in platelets followed by a reduction of
thromboxane A2 levels can be achieved by buccal absorption of a chewed 160–325
mg tablet of Aspirin.
Supplemental Oxygen is not cost effective in patients with ACS and whose arterial O2
saturation is normal. If hypoxemia is present O2 should be administered by nasal
prongs or face mask (2–4 L/min) for the 1st 6-12 hrs.
Sublingual Nitroglycerine can be given safely to most patients with STEMI provided
there is no contraindication.
Morphine is a very effective analgesic for the pain associated with STEMI. It should
be administered cautiously as it may reduce sympathetic mediated constriction of
arteriolar and venous system leading to venous pooling thus a reduction in cardiac
output and arterial pressure.
Intravenous Beta blockers are useful in the control of chest pain of STEMI. They
control pain effectively in some patients by diminishing myocardial oxygen demand
and hence ischemia. There is evidence that intravenous beta blockers reduce the risks
of reinfarction and ventricular fibrillation.
PCI is generally preferred over fibrinolysis when the diagnosis is in doubt, in the
Presence of cardiogenic shock, when there is increased risk of bleeding, atleast 2–3
hours of window period and when the clot is more mature and less easily lysed by
fibrinolytic drugs.
If no contraindications are present, fibrinolytic therapy should be initiated ideally
within 30 min of presentation (i.e., door-to-needle time ≤30 min). The fibrinolytic
agents like tissue plasminogen activator (tPA), streptokinase, Reteplase and
tenecteplase have been approved by the U.S. FDA for intravenous use in patients with
STEMI.
Thrombolysis in Myocardial Infarction (TIMI) grading system is a simple qualitative
scale used during angiography to assess the flow in the culprit coronary artery and
the goal of reperfusion therapy is TIMI grade 3.
Diet
Patients should be kept Nil per oral or only clear liquids by mouth for the first 4–12
hours in view of risk of vomiting.
The typical coronary care unit diet should provide less than or equal to 30% of total
calories as fat and a cholesterol content of less than or equal to 300 mg/d. Complex
carbohydrate diet should make up 50–55% of total calories. The diet should contain
food which is high in potassium, fibre and magnesium but low in sodium.
Hypertriglyceridemia and Diabetes mellitus are managed by restriction of
concentrated sweets in the diet.
Bowel Management
A diet rich in bulk, a bedside commode rather than a bedpan, and the routine use of a
stool softener such as dioctyl sodium sulfosuccinate (200 mg/d) are recommended. If
the patient remains constipated despite all these measures, a laxative can be
prescribed. It is safe to perform a gentle rectal examination on patients with STEMI.
Sedation
Benzodiazepines can be given to withstand the period of enforced inactivity with
tranquillity.
Antithrombotic: In conjunction with reperfusion strategies the primary goal of
treatment with antiplatelet and anticoagulant agents is to maintain patency of the
infarct-related artery. A secondary goal is to reduce the patient’s tendency to
thrombosis, mural thrombus formation or deep-venous thrombosis.
Three months of anticoagulation is recommended in patients with severe left
ventricular dysfunction, anterior location of the infarction, heart failure, a history of
embolism, 2D ECHO evidence of mural thrombus, or atrial fibrillation.
Acute intravenous beta blockade improves the myocardial oxygen supply-demand
relationship, reduces the infarct size, decreases pain, and decreases the incidence of
serious ventricular arrhythmias.
With ACE inhibitors or Angiotensin receptor blockers, maximum benefit is seen in
high-risk patients i.e those who are elderly or who have an anterior infarction, a prior
infarction, and/or globally depressed LV function.
MATERIAL AND METHODS
METHODS
Ethical Approval
This study was conducted after obtaining permission from the Institution review
board (IRB Number 11350 dated 04.06.2018 Appendix Number2) prior to
commencement of the study.
SETTING
This study was done in Christian Medical College, Vellore in the Acute Chest pain
unit run by the Cardiology department among patients who presented with acute chest
pain and were diagnosed to have ST elevation MI. The study was conducted from
June, 2018 to September, 2019. All the patients were recruited after 12 hours of
admission in view that their vital signs will be stabilised and as anthropometric
measurement could be done only once they are stabilised.
PARTICIPANTS:
Study Group:
Inclusion criteria:
Residents of Vellore or surrounding districts who consider themselves as Tamilians
and who presented to the acute chest pain unit with a diagnosis of ST elevation MI
(irrespective of the duration from the onset). Atleast2 of the following criteria must
be present-
-1. Chest / epigastric discomfort
-2. ST elevation more than 1 mm in limb leads and 2 mm in chest leads in more than 1 consecutive leads
-3. Serial elevation of cardiac enzymes
-4. New left bundle branch block
Patients who were diagnosed to have STEMI were divided into two group - young
(age less than or equal to 40 years) and old (age more than 40 years)
EXCLUSION CRITERIA –
Patient who cannot give consent or unwilling to participate.
METHODS:
Once patient were identified, they were given the information sheet, following which
written informed consent was obtained (Copy of Information sheet in Appendix no
3). All the study data were collected by the principal investigator on a specially
designed clinical research form (CRF) (Copy of CRF in Appendix no 4). The
participants of the study or their bystanders were interviewed and data collected.
Demographic Data including name, age, sex, occupation, height, weight, waist hip
ratio were collected. Addictions like smoking and regular alcohol consumption were
also questioned. Lifestyle parameter like poor dietary pattern (according to healthy
eating index 2005) mentioned in the appendix, psychosocial stress and inadequate
physical activity were also questioned. Laboratory parameters like fasting lipid
profile, homocysteine and HBa1c were also evaluated.
RISK FACTORS ASSESSED- 1. Dyslipidaemia
2. Abdominal obesity (waist to hip ratio) and BMI 3. STOP BANG score
4. Diabetes Mellitus 5. Smoking
6. Hypertension
7. Hyperhomocysteinemia 8. Alcohol intake
9. Family history 10. Poor dietary pattern 11. Lack of exercise 12. Psychosocial stress.
DATA SOURCE AND MEASUREMENT
1. DYSLIPIDAEMIA- Japan Atherosclerotic Society guidelines for diagnostic
criteria for screening of dyslipidaemia due to its simplicity was used for this
study. LDL value between 120-139 mg/dl was considered as Borderline hyper
LDL cholesterolemia and value more than or equal to 140mg/dl was considered
as hyper LDL cholesterolemia. HDL value < 40 mg/dl was considered as Hypo
-HDL cholesterolemia and Triglycerides value of more than or equal to 150
mg/dl was considered as hypertriglyceridemia. Majority of the lipid profile
were done in a fasting blood sample.
2. ABDOMINAL OBESITY/ OBESITY - INTERHEART study showed that
abdominal obesity was a greater risk factor than BMI, indicating that
measurement of waist-to-hip ratio should replace BMI as an indicator of
obesity. However, both BMI and waist to hip ratio were measured in each
patient and comparison between the two was done at the end of the study.
WHO protocol was used for measurement of the same. The waist
circumference was measured at the midpoint between the lower margin of the
last palpable rib and the top of the iliac crest. Hip circumference was measured
around the widest portion of the buttocks with each measurement taken twice.
Abdominal obesity was defined as waist to hip ratio above 0.9 for males and
0.85 for females. Grade 1 overweight was defined as BMI of 25-29.9kg/m2, 30-39.9kg/m2 as Grade 2 overweight or obesity and BMI >/= to 40 will be
recorded as Grade 3 overweight or morbid obesity.
3. STOP BANG SCORE - OSA as a risk factor for STEMI was assessed using
STOP BANG Score. It was calculated for each patient who were included in
the study. One point each was given for the eight questionnaire which include
- Whether they snore loudly (louder than talking or loud enough to be heard through the closed doors).
- Whether they often feel tired, fatigued, or sleepy during the daytime.
- Whether anyone had observed them stop breathing during sleep.
- Whether they were being treated for high blood pressure.
- BMI > 35 kg/m2.
- Age > 50 years.
- Neck circumference of more than 40 cm and
- Male gender.
4. DIABETES MELLITUS- WHO guidelines for Diabetes Mellitus was used for
diagnosing Diabetes Mellitus which includes HBa1c of equal to or more than
6.5, fasting blood glucose of more than or equal to 126 mg/dl and 2 hour 75 gm
Glucose load of more than or equal to 200 mg/dl. A random blood sugar more
than200 mg/dl with signs and symptoms of Diabetes Mellitus was considered
as Diabetes Mellitus. The duration of the disease were recorded in years.
Patients recently diagnoses (less than a year) or those diagnosed after
admission were taken as one year duration. Patients already diagnosed more
than a year ago were rounded off to the closest number. For example 19
months duration of diagnosed Diabetes Mellitus were taken as 2 years while14
months duration were taken as one year.
5. SMOKING AND OTHER FORMS OF TOBACCO CONSUMPTION-
Smoking is one of the most important risk factors for acute coronary syndrome
in young according to most of the studies done elsewhere. Each patient were
questioned regarding the history of smoking in last 1 year . An answer of YES
was considered as smoker and details of cigarette smoking was recorded in
terms of pack years. An answer of occasional smoking was considered as a
smoker. Other forms of tobacco consumption like khaini, beedi were also
questioned and recorded as smoker if they had regularly consume it at least 3
times in a week the duration of consumption were recorded in years.
6. HYPERTENSION- JNC 7 guidelines was used for definition of hypertension
and duration of the disease was recorded in years. Patients who were already on
antihypertensive medications were recorded as hypertensive. A single elevated
blood pressure recordings requiring antihypertensive medications were
registered as hypertensive. Patients having two persistent elevated blood
pressure of 8 hrs gap or who fulfil Sokolow Lyon criteria for LVH or Bifid P
waves on ECG without a pre-existing cardiac disease and without mid-
diastolic murmur were recorded as hypertensive. A cut off of more than or
equal to 140/90 was used for defining hypertension. Patients were not
separately divided into stage 1 hypertension (defined as systolic blood pressure
of 140-159 and diastolic blood pressure of 90-99 mmHg) and stage 2
hypertension (defined as systolic blood pressure of more than 160 mmHg and
diastolic blood pressure of more than 100 mmHg).
7. HOMOCYSTEINE LEVEL – The serum sample for homocysteine were taken
randomly irrespective of the time of day but majority were morning fasting
samples. The sample were appropriately transported along with ice.
Hyperhomocysteinemia was categorised as mild (15-30 micromol/L) ,
moderate (30-100 micromol/L) and severe as (> 100 micromol/L) based on the
levels of plasma homocysteine level.
8. ALCOHOL CONSUMPTION - According to the study - Patterns of Alcohol
Consumption and Myocardial Infarction Risk - Observations from 52 Countries
in the INTERHEART Case-Control Study, low levels of alcohol use were
associated with moderate reduction in the risk of MI. However, an episode of
heavy drinking was associated with an increased risk of acute MI in the
subsequent 24 hours, particularly in older individuals. Each participants were
questioned regarding whether they consume ethanol in the last 12 months and
if so, how frequently they consume - less than once per month, less than once
per week, 1-2 times per week, 3-4 times per week, 5-6 times per week and
daily. History of last drink and amount of consumption in last 24 hours prior
to MI onset was questioned to check whether a binge drink has any role as a
trigger for MI. Heavy episodic drinking was defined as consumption of >/= 6
alcoholic drinks within 24 hours prior to MI.
9. FAMILY HISTORY – History of sudden unexplained deaths, any forms of
acute coronary events and cerebrovascular accidents among the siblings, first
cousins, maternal and paternal aunt and uncle, parents and grandparents was
obtained.
10. POOR DIETARY PATTERNS- According to the study “Influence of dietary
patterns on the risk of acute myocardial infarction in China population: the
INTERHEART China study” they concluded that unhealthy diet
increases the risk of a coronary event.
In our study Healthy Index Calculator based on USDA healthy eating Index
2005 was used regarding dietary pattern the patient followed daily. This
calculator was used as it was the simplest means of measuring dietary patterns
and grade them subsequently. Components of healthy Index calculator include - Calories Per Day: in calories.
- Total Fruit (includes 100% juice) in cups; Whole Fruit (not juice) in cups.
- Total Vegetables in cups; Dark Green and Orange Vegetables in cups.
- Total grains in ounces.
- Whole Grains in ounces.
- Milk (includes all milk products, such as fluid milk, yogurt, and cheese, and soy beverages) in cups.
- Meat and Beans in ounces.
- Oils (includes non-hydrogenated vegetable oils and oils in fish, nuts, and seeds) in grams.
- Saturated fat in grams.
- Sodium in grams.
- Calories from Solid Fats, Alcoholic Beverages, and Added Sugars (SoFAAS) in calories.
The Kcal values were calculated after discussing with dietician regarding the
amount of kcal average piece of idli, dosa and a cup of rice contained. Based
on these parameters , values of 0-51 will be included as poor, 51-80 as needs
improvement and 80-100 as Good. Score below 80 will be considered as poor
dietary patterns.
11. LACK OF EXERCISE – According to “the Physical activity levels, ownership of
goods promoting sedentary behaviour and risk of myocardial infarction : results of
the INTERHEART study” lack of exercise was one of the risk factors for acute
coronary syndrome independent of the age. In our study physical activity during
work and during leisure time was questioned to each participants.
Physical activity during work was assessed by asking the participants how active
they had been at work with the following categorical responses:
- subjects who do not work,
- mainly sedentary,
- predominantly walking at one level,
- mainly walking including walking uphill or lifting heavy objects,
- heavy physical labour.
Those who choose mainly walking uphill or lifting heavy objects or heavy physical
labour were included in adequate physical activity. For leisure-time activity,
participants were asked ‘Do you play sports or exercise during your leisure
time?’ as a yes or no response question. Of those who responded yes to this
question, a second question about the number of hours per week spent
in exercise and number of months per year that the individual carried out the
exercise was asked. The physical activity of at least 150 min/week was categorised
as adequate physical activity.
12. PSYCHOSOCIAL STRESS – According to the study “Association of
psychosocial risk factors with risk of acute myocardial infarction in 11119
cases and 13648 controls from 52 countries (the INTERHEART study): case-
control study” - presence of psychosocial stressors was associated with
increased risk of acute myocardial infarction. Psychosocial stress was assessed
by using 5 simple questions about stress at home, stress at work, financial
stress, major events in the past 1 year and average duration of sleep in a day
over last 1 month (as a supporting parameters as those who are on stress
mentally are not expected to have adequate sleep) and the duration was
recorded in hours of sleep per day. A sleep duration of 8 hrs will be considered
as adequate sleep. If any of the above parameter are present, they were
considered as having psychosocial stress.
Sample Size-
The sample size was calculated using Kaur(21) study . For each individual risk factor
the sample size was calculated based on the OR reported. The following table presents
the sample size for each risk factors. The significant risk factors were taken for sample
size calculation and the calculation were based on 80 % power and 5% error.
Risk factors <40 years >40 years Sample size (in each arm)
Smoking 61.4 24.1 30
Alcohol 42.9 21.7 77
Obesity 69 59 361
Homocysteine 54.9 30 61
Rural life style 43.5 36.1 765
A minimum of 77 old and 77 young adults are needed to achieve for a difference of 21.3% ( 42.9 -21.7 = 21.2 % in alcohol ) among the young and old adult.
Sample size was calculated using
Statistical methods:
Categorical variables were summarized using counts and percentages. Quantitative
variables was summarized using mean and standard deviation or median and IQR.
The difference in risk factors was tested using z test for proportions and it was
presented with 95% CI. The estimate of effect was presented as odds ratio (95%
CI). Logistic regression was used to find the effect size adjusted for confounders
considering each risk factor as outcome.
Funding and approval:
Our study was funded by an internal grant of the Hospital called the Fluid grant.
Study algorithm:
Patients who presents to acute chest pain unit with STEMI
Age less than or equal to 40 years-to look for
-Smoking -Hypertension -Diabetes mellitus
-waist hip ratio -Dyslipidaemia -family history -Poor dietary patterns -Inadequate physical activity
-Alcohol intake -Psychosocial stress
-STOP BANG score
Age more than 40 years old -to look for all the risk factors
-Smoking --hypertension -Diabetes Mellitus
-waist hip ratio -Dyslipidaemia -Family history -Poor dietary patterns -Inadequate physical activity
-Alcohol intake -Psychosocial stress
-STOP BANG score
RESULTS
Between April 2018 and September 2019, all patients with a diagnosis of acute
coronary syndrome who presented to acute chest pain unit were screened for the
study.
A total of 159 patients were included in the study of which 79patients were age less
than or equal to 40 years and 80 patients were above 40 years.
BASELINE CHARACTERISTICS-
The mean age of the patients was 46.98 years and 87.42% were male. The following
table gives the baseline characteristic combining both the study population.
Table 1 – BASELINE CHARACTER COMBINING ALL AGE GROUP.
Variables N Mean SD P25 Median P75
Age 159 46.98 14.55 36 42 57
Total cholesterol 158 178.32 45.88 150 175 205
LDL 158 119.22 33.51 94 119.50 143
Triglycerides 158 199.41 253.60 106 142.50 210
HDL 158 37.14 12.92 30 36 42
Waist Hip ratio 159 0.96 0.07 0.92 0.96 1
BMI 159 25.72 3.83 23.10 25.40 27.90
Stop bang score 159 2.61 1.34 2 3 3
Diabetes mellitus duration in years
71 5.93 6.63 1 5 9
Hba1c at admission 150 7.21 2.19 5.70 6.20 8.30
Smoking in pack years 72 15.40 12.33 8 10 20
Hypertension and duration 48 5.60 5.22 2 5 5
Homocysteine 143 18.85 12.65 10.90 15 21.30
The following table shows the baseline characters in age less than or equal to
40.Majority of the patients were male and they comprise 92.41 % while female
comprise 7.59 % only.
Table2 – BASELINE CHARACTERISTICS OFYOUNG PATIENTS WITH STEMI.
Variables N Mean SD P25 Median P75
Total cholesterol
79 187.92 47.32 154 182 210
LDL 79 126.11 30.88 106 127 144
Triglycerides 79 213.19 240.18 112 150 251
HDL 79 36.97 10.12 30 36 43
Waist hip ratio 79 0.95 0.08 0.90 0.94 0.98
BMI 79 25.94 4.09 23.10 25.40 27.80
Stop bang score 79 2.46 1.47 1 2 3
Diabetes mellitus duration in years
24 3.75 3.57 1 2 5
Hba1c at admission
73 6.72 2.09 5.50 5.70 7.10
Hypertension duration in years
16 3.81 2.86 2 4 5
Smoking in pack years
44 9.98 5.27 5 10 10
Homocysteine 73 23.81 15.22 13.40 16.20 32.50
.
Table3 –BASELINE CHARACTERISTICS IN OLDER PATIENTS (AGE >40 YEARS) WITH STEMI
Variable N Mean SD P25 Median P75
Total cholesterol
79 168.71 42.54 138 167 200
LDL 79 112.33 34.79 87 107 139
Triglyceride 79 185.63 267.18 98 140 207
HDL 79 37.30 15.28 29 36 42
Waist hip ratio
80 0.97 0.05 0.94 0.97 1
BMI 80 25.52 3.58 23.35 25.35 27.90
STOP BANG 80 2.76 1.20 2 3 3
Diabetes mellitus duration
47 7.04 7.53 2 5 10
Hba1c at admission
77 7.67 2.20 6 6.50 9.40
Hypertension duration in years
32 6.50 5.91 2 5 7.50
Smoking in packed years
28 23.93 15.24 10 20 35
Homocysteine 70 13.67 5.84 9.10 12.95 17.60
LDL WITH STEMI-
Normal LDL cholesterol level was noted in 40.5% among the young and 59.47%
among the old STEMI. Borderline elevated LDL level according to Japan
Atherosclerotic society was noted in 27.5% among the young and 16.46% among the
old. Hyper LDL cholesterolemia was noted in 31.65% and 24.05% among the young
and old respectively. The mean LDL was 126mg/dl among the young while it was
112mg/dl among the old. The p-value was 0.008 for total cholesterol and 0.009 for
LDL on comparing both the group therefore it was statistically significant.
Table 5 – LDL LEVEL WITH STEMI
LDL Young MI Old MI Total
<120 32 47 79
120-139 22 13 35
>140 25 19 44
Total 79 79 158
Table 6 – LDL LEVEL WITH STEMI
LDL Young MI Old MI Total
<120 32 47 79
>120 47 32 79
Total 79 79 158
HDL AND STEMI
HDL level below 40 was noted in 66.56% among the young STEMI compared to
69.62% among the OLD MI. HDL value above or equal to 40 was noted in 35.44 %
among the young while it is 30.38% among the old MI. The median was noted to be
36mg/dl among both the group. The p value was 0.858 when comparing the
prevalence between both the group hence statistically it was not significant.
Table 7 – HDL AND STEMI
HDL YOUNG MI OLD MI TOTAL
>/=40 28 24 52
<40 51 55 106
TOTAL 79 79 158
TRIGLYCERIDE LEVEL WITH STEMI –
Triglycerides value above 150 was noted in 50.63% among the young MI whereas it
was 43.04% among the old MI. Value below 150 was noted in 49.37 % among the
young while it was 56.96% among the old. The median triglyceride level was 150
among the young whereas it was 140 among the old MI. The p value on comparing
both the group was 0.090 which was not statistically significant.
Table 8 – TRIGLYCERIDE LEVEL WITH STEMI
TRIGLYCERIDES YOUNG MI OLD MI TOTAL
<150 39 45 84
>/= 150 40 34 74
TOTAL 79 79 158
ABDOMINAL OBESITY AND STEMI
The prevalence for abdominal obesity was 79% among the young and 80% among the
old STEMI group. The mean waist hip ratio was 0.95 among the young while it was
0.97 among the old STEMI. The p value was 0.018 which was statistically significant.
Table 9 – ABDOMINAL OBESITY WITH STEMI
Abdominal obesity Young Old Total
Present 60 72 132
Absent 19 18 27
Total 79 80 159
STEMI AND BMI
Grade 1 overweight was noted in 37.97% among the young and 40% among the old.
Grade 2 overweight was noted in 15.19% among the young and 13.75% among the
old. BMI of less than 25 was noted in 46.84% among the young STEMI and 46.25 %
among the old STEMI. The p value was 0.491 therefore it was not statistically
significant.
Table 10 – BMI AND STEMI
BMI Young Old Total
<25 37 37 74
25-29.9 30 32 62
30 – 30.9 12 11 23
79 80 159
STOP BANG SCORE AND STEMI –
The prevalence of STOP - BANG score above 3 was noted in 53% among the young
against 61% among the old. The median for STOP BANG score among the young was
2.46 and for old STEMI it was 2.76. As there was high prevalence of STOP BANG
score above 3 on both the sample size the p value on comparing both the group was 0.2456 which was not statistically significant.
DIABETES MELLITUS AND STEMI -
Unlike most other studies the incidence of Diabetes Mellitus was lower among the
young group on comparing to the older STEMI. Diabetes Mellitus was present in
31.65% among the young whereas it was 58.75% among the old STEMI. The p-value
was 0.001 which is statistically significant.
The median HBA1c is 5.7 among the young and 6.5 among the old with a p
value of 0.02 which is statistically significant.
The median for diabetes mellitus duration was 2 years among the young while it was 5
years among the old. The p value is 0.020 which was statistically significant.
Table11 –DIABETES MELLITUS AND STEMI
Diabetes mellitus Less than 40 More than 40 Total
Present 25 47 72
Absent 54 33 87
Total 79 80 159
SMOKING AND STEMI
Smoking was noted in 55.75 % among the young and 35% among the old. The p –
value was 0.009 which was statistically significant on comparing both the group. The
median for pack years of smoking was 10 among the young and 20 among the old
with a p value of < 0.001 which is statistically significant. None of the patients in both
age groups gave history of consumption of other forms of tobacco.
Table 12 – SMOKING AND STEMI
Smoking Less than 40 Above 40 Total
Present 44 28 72
Absent 35 52 87
Total 79 80 159
HYPERTENSION AND STEMI -
Hypertension was noted in 16.67% among the young and 40%among the old. The
prevalence was more in the older cohort compared to the young. The p-value is 0.001
which is statistically significant. The median for hypertension duration is 4 years
among the young and 5 years among the old. The p value is 0.093 for the duration
which is not statistically significant.
Table 13 – HYPERTENSION AND STEMI
Hypertension Less than 40 Above 40 Total
Present 13 32 45
Absent 65 48 113
Total 78 80 158
HOMOCYSTEINE LEVEL WITH STEMI
The prevalence of mild hyperhomocysteinemia was 35.62% in the young and 32.86%
in the old. The prevalence of moderate hyperhomocysteinemiawas 28.77% among
the young and 2,86% in the old. The p value was <0.001 which is statistically
significant The median level of homocysteine was 16.20 among the young and
12.95% among the old.
Table 14 - HOMOCYSTEINE LEVEL AND STEMI
HOMOCYSTEINE LEVEL
YOUNG MI OLD MI TOTAL
<15 26 45 71
15-30 26 23 49
30.1 – 100 21 2 23
73 70 143
ALCOHOL AND STEMI
The prevalence of alcohol consumption was 30.8%, among the young and 13.75%
among the old with with a p value of 0.011 which is statistically significant. None of
the patients had a history of binge drink 24 hrs prior to the acute episode.
Table 15 – ALCOHOL CONSUMPTION AND STEMI
ALCOHOL Young MI Old MI Total
Present 24 11 35
Absent 55 69 124
Total 79 80 159
FAMILY HISTORY OF SUDDEN DEATH AND STEMI
The prevalence of sudden unexplained death or family history of acute coronary
syndrome was present in 13.92% among the young MI while 10% was noted among
the old MI. On comparing both the groups the p value is 0.446 among which is not
statistically significant.
Table 16 – FAMILY HISTORY OF SUDDEN DEATH AND STEMI
Sudden death Young MI OLD MI Total
Present 11 8 19
Absent 68 72 140
Total 79 80 159
POOR DIETARY PATTERN AND STEMI-
Our study showed that poor dietary pattern was noted in97.47% among the young
STEMI and 98.75% among the old STEMI. Combining both group poor dietary
pattern was present in 98.11%. As both of the group had similar findings regarding the
outcome of poor dietary pattern and STEMI, on comparing the difference between
both the group the p value was 0.553 which was not statistically significant.
Table 17 – POOR DIETARY PATTERN AND STEMI
Poor diet Young Old Total
Present 77 79 156
Absent 2.53 1 3
Total 79 80 159
LACK OF EXERCISE AND LACK OF PHYSICAL ACTIVITY WITH STEMI
Our study showed that lack of physical activity was noted in 97.47% among the
Young, 92.41% among the old and 94.94% overall. Although lack of physical activity is a risk factor for both the study group on comparing both the group, the p value was
0.147 which was not statistically significant.
Table 18 – LACK OF EXERCISE OR LACK OF PHYSICAL ACTIVITY WITH STEMI
Lack of exercise Young Old Total
Present 77 73 150
Absent 2 6 8
Total 79 79 158
