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CERTIFICATE
This is to certify that the dissertation entitled “PLASMA FIBINOGEN LEVEL IN NEWLY DETECTED TYPE 2 DIABETES MELLITUS PATIENTS IN A TERTIARY CARE CENTRE” is a bonafide work done by DR. E. NATARAJAN registration number 201711010, at Madras medical college, Chennai in partial fulfillment of the university rules and regulations for the award of M.D., Degree in General Medicine (Branch- I) under our guidance and supervision during the academic year 2017 – 2020.
Prof. Dr. S. RAGUNANTHANAN, M.D., Prof. Dr. R. PENCHALAIAH, M.D., Director (I/c) and Professor, Professor of Medicine,
Institute of Internal Medicine, Institute of Internal Medicine, Madras Medical College & Madras Medical college &
RGGGH, Chennai – 600003 RGGGH, Chennai – 600003
Prof. Dr. R. JAYANTHI M.D., FRCP (Glasg) The Dean , MMC & RGGGH
Chennai – 600003
DECLARATION
I, Dr. E. NATARAJAN, Registration Number 201711010 solemnly declare that this dissertation entitled “PLASMA FIBRINOGEN IN NEWLY DETECTED TYPE 2 DIABETES MELLITUS PATIENTS IN A TERTIARY CARE CENTRE” was done by me at Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai during 2017-2020 under the guidance and supervision of my Chief Prof. Dr. R. PENCHALAIAH M.D. This dissertation is submitted to the Tamil Nadu Dr.M.G.R. Medical University towards the partial fulfillment of the requirements for the award of M.D. Degree in General Medicine (Branch-I).
Place: Chennai-3 Signature of Candidate Date:
ACKNOWLEDGEMENT
I owe my thanks to Dean, Madras Medical College and Rajiv Gandhi Government General Hospital, Dr. R. JAYANTHI, M.D., FRCP for allowing me to avail of the facilities needed for my dissertation work.
I am grateful to my beloved mentor Prof. Dr. S. RAGUNANTHANAN, M.D., Director and Professor, Institute of Internal Medicine, Madras Medical College and Rajiv Gandhi Government General Hospital, for permitting me to do the study and for his encouragement.
With extreme gratitude, I express my indebtedness to my beloved Chief and teacher Prof. Dr. R. PENCHALAIAH, M.D., for his motivation, advice and valuable criticism, which enabled me to complete this work.
I would like to extend my gratitude to Prof. Dr. P.DHARMARAJAN.
M.D., D.Diab., for his expert guidance in conducting this study.
I am extremely thankful to my Assistant Professors, Dr. DAMODARAN DHANASEKARAN, M.D., and Dr. T. SIVAKUMAR M.D., for their guidance and encouragement.
I am also thankful to all my unit colleagues and other post-graduates in our Institute for helping me in this study. My sincere thanks also go to all the patients and their families who were co-operative during the course of this study.
Dr. E. NATARAJAN
LIST OF ABBREVIATIONS
ADA - AMERICAN DIABETES ASSOCIATION
AGE - ADVANCED GLYCATION PRODUCTS
APTT - ACTIVATED PARTIAL THROMBOPLASTIN TIME
BMI - BODY MASS INDEX
CAD - CORONARY HEART DISEASE
CHF - CONGESTIVE HEART FAILURE
CT - COMPUTED TOMOGRAPHY
CVA - CEREBRO VASCULAR ACCIDENTS
CRP - C- REACTIVE PROTEIN
DCCT - DIABETES CONTROL AND COMPLICATIONS TRIAL
DM - DIABETES MELLITUS
FBS - FASTING BLOOD SUGAR
FLP - FASTING LIPID PROFILE
GAD - GLUTAMIC ACID DECARBOXYLASE
GDM - GESTATIONAL DIABETES MELLITUS
GLUT - GLUCOSE TRANSPORTERS
GLP - GLUCAGON LIKE PEPTIDE
HDL - HIGH DENSITY LIPOPROTEIN
HRT - HORMONE REPLACEMENT THERAPY
IA- 2 - INSULIN AUTOANTIBODIES 2
IDF - INTERNATIONAL DIABETES FEDERATION
LDL - LOW DENSITY LIPOPROTEINS
PAI - PLASMINOGEN ACTIVATOR INHIBITOR
PPBS - POST PRANDIAL BLOOD SUGAR
PT - PROTHROMBIN TIME
VLDL - VERY LOW DENSITY LIPOPROTEINS
UKPDS - UNITED KINGDOM PROSPECTIVE DIABETES STUDY
CONTENTS
S. NO TITLE PAGE NO.
1 INTRODUCTION 1
2 AIMS AND OBJECTIVES 4
3 REVIEW OF LITERATURE 5
4 MATERIALS AND METHODS 52
5 OBSERVATION AND RESULTS 56
6 DISCUSSION 76
7 CONCLUSION 82
8 LIMITATIONS OF STUDY 84
9 BIBILIOGRAPHY 85
10 ANNEXURES - PROFORMA
- INFORMATION SHEET - PATIENT CONSENT FORM - ETHICAL COMMITTEE
APPROVAL
- PLAGIARISM SCREENSHOT - PLAGIARISM CERTIFICATE - MASTER CHART
INTRODUCTION
1
INTRODUCTON
Diabetes mellitus is a disease comprised of a group of metabolic disorders which share the common phenotype of hyperglycemia[1]. The worldwide prevalence of diabetes mellitus has increased drastically over the past 20 years. It is estimated that the number of patients with diabetes mellitus will continue to increase in upcoming years. Based upon the current trends, approximately 360 million people will be diagnosed with diabetes by the year 2030[2].
Diabetes mellitus is classified based upon the pathophysiologic process leading on to hyperglycemia, as opposed to previous criteria such as age of onset or type of treatment. There are two main categories of diabetes mellitus, such as type 1 or type 2 DM. Though the prevalence of both type 1 and type 2 diabetes is increasing worldwide, the prevalence of type 2 diabetes mellitus is expected to increase much more rapidly in upcoming years because of increasing prevalence of obesity and reduced physical activity[3]. The metabolic dysregulation exhibited by diabetes mellitus produces several secondary pathophysiological changes in multiple organ systems that lead on to a great burden to the individual and to the health care system. The real burden of the disease is mostly due to its micro vascular and macro vascular complications. Macro vascular complications including acute myocardial infarction and stroke are the most important causes for the mortality and morbidity in the patients with type 2 diabetes mellitus. Coronary artery disease is the leading cause of death among diabetic patients and it accounts for about three folds as many as deaths among patients with diabetes mellitus when compared with non-diabetics [4].
2
It has been now realized that the traditional risk factors for cardiovascular diseases including smoking, hypercholesterolemia, obesity, physical inactivity, family history may account only for one half of the actual risk. So, it has become important to evaluate and identify other risk factors, especially the factors which can be easily modifiable. Some of those are estrogen deficiency, plasminogen activator inhibitor type 1, C – reactive protein, endogenous tissue plasminogen activator (tPA) and homocysteine.
Fibrinogen is one among such factors. It is the precursor molecule of fibrin and an important determinant of blood viscosity and aggregation of platelets.
Elevated viscosity of plasma due to raised fibrinogen levels can significantly increase the risk of microvascular complications in diabetic patients [4-5]. Likewise, many studies have also shown that elevated levels of fibrinogen identified to be an important risk factor for coronary events [7-9]. Evidence also suggests that increased fibrinogen levels may also be involved in the development of atherosclerotic lesions starting with the early stages of plaque formation[10].
Comparing various hematological factors, elevated fibrinogen levels as a risk factor in diabetics plays an important role in the development of complications[11]. Diabetes mellitus is often associated with a low grade inflammation and as a result of this there is an increased production of interleukin – 6. This interleukin – 6 stimulates the hepatocytes of the liver to produce increased amounts of fibrinogen representing the important link between the inflammation and hypercoagulable state[12].
3
Fibrinogen levels can be reduced to considerable levels by life style interventions and with drugs. This gives a possibility that measurement of plasma fibrinogen may help us in disease prediction and prevention[13].
AIMS AND
OBJECTIVES
4
AIMS AND OBJECTIVES OF THE STUDY
To study the plasma fibrinogen levels in newly detected Type 2 Diabetes mellitus patients in a tertiary care centre.
SECONDARY OBJECTIVES
To study the correlation of plasma fibrinogen with various parameters including age, sex , FBS, PPBS, and HbA1C.
REVIEW OF
LITERATURE
5
REVIEW OF LITERATURE
HISTORY OF DIABETES MELLITUS
The term ”diabetes” was coined by Areatus of Cappodocia (81-133 AD).
Later, the term “mellitus” ( honey sweet ) had been added by Thomas Willis in 1675 after noting the sweetness of urine and blood of patients. Only in 1776 it was first discovered that presence of excess sugar in urine and blood as the reason for its sweetness by Dobson. The term diabetes in Greek literally means “I run through siphon”. Johann Peter Frank was the one who was credited with distinguishing diabetes mellitus and diabetes insipidus in 1794.
A milestone in the history of diabetes was the demonstration of the role of liver in the glycogenesis, and the concept of diabetes which is due to increased glucose production by Claude Bernard in 1857. Later, the role of pancreas in the pathophysiology of diabetes mellitus was established by Mering and Minkowski 1889. This was followed by another important milestone which is the isolation of insulin and its clinical use by Banting and Best in 1921. Several trials were done to produce a orally administered hypoglycemic agent which ended successfully by marketing of Tolbutamide and Carbutamide in 1955. Even in ancient India , Susrutha and Charaka have mentioned about diabetes mellitus in their books.
During the last few decades there have been extensive research work done in the field of diabetes mellitus in order to develop new drugs and treatment protocols.
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7
Islets of Langerhans consist of four types of cells:
1. A cells or alpha cells, which secrete glucagon 2. B cells or beta cells, which secrete insulin
3. D cells or delta cells, which secrete somatostatin
4. F cells or PP cells, which secrete pancreatic polypeptide.
INSULIN :
Insulin is a polypeptide which has 51 amino acids and a molecular weight of 5,808 Daltons. It is secreted by the B cells or the Beta cells in the islets of pancreas. It has two amino acid polypeptide chains known as alpha and beta chains. They are linked together by a disulphide bond. The alpha chain contains 21 amino acids and the beta chain contains 31 amino acids. The biological half life of insulin is about 5 minutes.
Synthesis of insulin occurs in the rough endoplasmic reticulum of beta cells of islets of pancreas[20]. It is initially synthesized as preproinsulin, that give rise to proinsulin. Proinsulin is converted into insulin and C – peptide through a series of cleavage reactions. C peptide is a connecting peptide which connects both the alpha and beta chains together. At the time of secretion of insulin, C peptide is detached. The basal level of insulin in plasma is about 10 microunits/ m L.
Binding of insulin to its receptor is very essential for its action as well as for its removal from the circulation and for its degradation. Insulin is
8
metabolised in the liver and kidney and degraded by an enzyme known as Insulin protease or Insulin- degrading enzyme.
ACTIONS OF INSULIN:
Figure 2. Structure of insulin
Insulin is an essential hormone which is concerned with the regulation of carbohydrate metabolism and blood glucose levels. Insulin also has a role in the metabolism of proteins and fats.
1) ACTION ON CARBOHYDRATE METABOLISM :
Insulin is the only anti diabetic hormone produced in the body. Insulin reduces blood glucose value by its following actions on carbohydrate metabolism.
a) Insulin increases the transport and uptake of glucose by the cells by increasing the permeability of cell membrane to glucose. Insulin also increases the number of glucose transporters, especially GLUT 4 in the
9
membrane. Glucose is transported into the cells by sodium – glucose symport pump.
b) Insulin promotes the peripheral utilization of glucose.
c) Insulin promotes the rapid conversion of glucose into its storage form glycogen a process termed as glycogenesis. The formed glycogen is stored in the muscle and liver.
d) Insulin inhibits glycogenolysis i.e, breakdown of glycogen into glucose from the muscle and liver.
e) Insulin prevents gluconeogenesis which means formation of glucose from proteins by inhibiting the release of amino acids from the muscle.
2) ACTION ON PROTEIN METABOLISM :
Insulin facilitates the synthesis and storage of proteins and inhibits the cellular utilization of proteins by following actions.
A) Facilitating the transport of amino acids into the cell from plasma, and by enhancing the permeability of cell membrane for amino acids.
B) Enhancing protein synthesis by influencing the transcription of DNA and by increasing the translation of Messenger RNA.
C) Preventing the protein catabolism by decreasing the activity of cellular enzymes which act on proteins.
D) Prevention of conversion of proteins into glucose.
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3) ACTION ON FAT METABOLISM:
Insulin stimulates the synthesis of fat and also enhances the storage of fat in the adipose tissue.
a) Insulin promotes the transport of excess glucose into the cells, notably into the hepatocytes. This glucose is being used for the synthesis of fatty acids and triglycerides.
b) Insulin also facilitates the transport of free fatty acids into the adipose tissue.
c) Insulin promotes the storage of fat in adipose tissue by preventing the enzymes which degrade the triacylglycerol.
4) ACTION ON GROWTH :
Insulin along with growth hormone, promotes growth of body by its anabolic action on proteins. It increases the transport of amino acids into the cells and synthesis of proteins in the cells. It also has the protein sparring effect which means conservation of proteins by increasing the glucose utilization by the tissues.
MODE OF INSULIN ACTION :
Insulin binds with the receptor protein and forms the insulin receptor complex. This complex does the action by activating the intracellular enzyme system.
11
INSULIN RECEPTOR :
Insulin receptor is a tetramer, made up of four glycoprotein subunits ( two alpha subunits and two beta subunits ). The alpha subunits protrude through the outside of the cell and the beta subunit protrude inside of the cell. The alpha and beta subunits are linked together by disulphide bonds.
Intracellular surfaces of alpha subunits have the protein kinase enzyme activity.
Figure 3. Structure of insulin receptor
12
Whenever the insulin binds with the alpha subunit of the receptor protein , the tyrosine kinase activity at the beta subunit is activated by means of autophosphorylation.
Activation of tyrosine kinase acts on many intracellular enzymes by phosphorylating them. Because of this some enzymes are activated whereas others are inactivated. In this way insulin action is exerted on the target tissue by the stimulation of some enzymes and inactivation of other enzymes.
Figure 4. Biphasic insulin secretion
13
REGULATION OF INSULIN SECRETION :
Insulin secretion is primarily regulated by blood glucose levels. In addition, other factors like amino acids, lipid derivatives, gastrointestinal hormones, endocrine hormones and autonomic nervous system have a role on regulation of insulin secretion.
Figure 4a. Mechanism of release of insulin from beta cells of pancreas.
14
When blood glucose level is normal, the rat of insulin secretion is low.
When the blood glucose level rises, the rate of insulin secretion also rises very rapidly.
Increase in blood glucose level after meals produces biphasic effect on plasma level of insulin.
DIABETES MELLITUS :
Diabetes mellitus is one of the most common metabolic disorders. It is a disorder of carbohydrate, protein, and fat metabolism due to absolute or relative deficiency of insulin production and also with varying degree of insulin resistance[19]. The worldwide prevalence of diabetes mellitus has increased drastically, from an estimated cases of 30 million in 1985 to 415 million in 2017.
Based upon current trends, the IDF predicts that about 642 million people will have diabetes mellitus by the year 2040. Diabetes mellitus results in long term complications including microangiopathy and acceleration of macroangiopathy[18].
Diabetes mellitus is classified on the basis of the etiologic and pathogenic process leading to hyperglycemia, which is against the earlier criteria such as age of disease onset or type of treatment given. There are two broad categories of DM, such as type 1 and type 2 DM. However, there is further recognition of other forms of diabetes in which molecular pathology is better understood and many types are associated with single gene defect.
15
CLASSIFICATION OF DIABETES MELLITUS :
1. TYPE 1 DIABETES MELLITUS ( due to beta cell destruction in the islets of pancreas, leading on to absolute insulin deficiency )
A) Immune mediated B) Idiopathic
2. TYPE 2 DIABETES MELLITUS ( predominantly due to insulin resistance with relative insulin deficiency )
3. HYBRID FORMS OF DIABETES
A) Slowly evolving immune related diabetes of adults B) Ketosis prone type 2 diabetes
4. OTHER SPECIFIC TYPES:
A) Monogenic diabetes
- Monogenic defects of beta cell function - Monogenic defects in insulin action B) Diseases of the exocrine pancreas C) Endocrine disorders
D) Drug or chemical induced E) Infections
F) Uncommon specific forms of immune mediated diabetes G) Other genetic syndromes sometimes associated with diabetes
5) UNCLASSIFIED (This category should be used temporarily when there is not a clear diagnostic category especially close to the time of diagnosis of diabetes
16
6) HYPERGLYCEMIA FIRST DETECTED DURING PREGNANCY A) Diabetes mellitus in pregnancy
B) Gestational diabetes mellitus.
CRITERIA FOR DIAGNOSIS OF DIABETES MELLITUS :
• Symptoms of diabetes plus random blood glucose concentration more than or equal to 11.1 mmol/L (200 mg/dL) or
• Fasting plasma glucose more than or equal to 7 mmol/ L (126 mg/dL) or
• Hemoglobin A1c more than 6.5% or
• 2- hour plasma glucose more than or equal to 11.1 mmol/L (200mg/ dL) during an oral glucose tolerance test.
TYPE 1 DIABETES MELLITUS
Type 1 diabetes mellitus roughly constitutes for about 5 - 10 % of all diabetes mellitus patients. Earlier it was designated as Insulin dependent Diabetes mellitus (IDDM). It usually results from interactions of genetic, environmental and immunological factors that finally leads on to immune mediated destruction of the beta cells of the islets of langerhans in the pancreas which ultimately leads to insulin deficiency.
17
Type 1 DM can develop at any age but most of the times it is seen before the age of 20 years. Most of the individuals with type 1 DM have the markers for islet directed auto immunity. However, certain individuals have the clinical features of type 1 DM but lack the markers indicative of an autoimmune process and this group of people are thought to develop insulin deficiency by some unknown non immune mechanism and more importantly they are ketosis prone.
IMMUNOLOGICAL FACTORS:
Most of the individuals with type 1 DM will have evidence for autoimmunity.
Prevalence of type 1 DM is seen in higher proportion in patients with other autoimmune diseases such as Graves disease, Addison disease and Hashimato thyroiditis. Islet cell autoantibodies area composite of multiple antibodies which are directed against the pancreatic islet cell molecules such as GAD, IA-2/ICA- 512, and ZnT- 8, and serve as a marker of autoimmunity in type 1 diabetes mellitus[21]. Assays for the detection of auto antibodies to GAD-65 and insulin are available commercially. Testing for ICAs can be useful in identifying the type of DM as type 1 and in identifying non diabetic individual at risk of developing type 1 DM. ICAs are usually present in majority of people ( > 85% ) identified with new onset type 1 DM, in minority of individuals with type 2 DM (5-10%) and in patients with GDM ( <5%) occasionally. Increasing number of antibodies are often associated with an increased risk for developing diabetes.
18
GENETIC FACTORS:
Many genetic factors have been involved in the causation of type 1 DM. The concordance of type I diabetes mellitus in identical twins ranges from 40-60 %, indicating that there is additional modifying factors are likely to be involved in determining whether diabetes develops or not. The gene for type 1 diabetes mellitus is located in the HLA region of chromosome 6. Polymorphisms in the HLA complex account for about 40 – 50% of the risk involved in development of type 1 diabetes mellitus.
Most individuals with type 1 DM have the involvement of HLA DR3 and /or DR4 haplotype. Genotyping of HLA loci have shown that the haplotypes DQA1*0301, DQB1*0302, and DQB1*0201 are the most strongly associated with type 1 DM. The haplotypes DQA1*0102, DQB1*0602 are very rare in patients with type 1 DM and appears to exert protection from type 1 DM. In addition to MHC class 2 associations, genome studies have shown that at least 20 additional genetic loci contributes to the susceptibility for the development of type 1 diabetes mellitus ( eg., the CTLA-4 gene, interleukin 2 receptor, and PTPN 22., etc)
ENVIRONMENTAL FACTORS:
A vast number of environmental factors have been proposed for the triggering if the autoimmune process in genetically susceptible individuals; but none has been conclusively linked to the causation of type 1 DM. Several environmental factors include certain viruses (coxsackie, rubella, enterovirus most
19
predominantly)[22] , bovine milk proteins, nitrosurea products, deficiency of vitamin D[26,27] , and environmental toxins.
TYPE 2 DIABETES MELLITUS :
Type 2 diabetes mellitus constitutes for about 85 – 90 % of all diabetes mellitus cases[32]. Previously it was called as Non insulin dependent diabetes mellitus ( NIDDM ) , Adult onset diabetes etc.
Etiology and Pathogenesis
Insulin resistance and abnormal insulin secretion are key to the development of type 2 diabetes mellitus[33]. Although the primary defect is controversial, most studies supported the fact that insulin resistance precedes an insulin secretory defect but the disease develops only when insulin secretion becomes inadequate[35]. A recent study has indicated that beta cell dysfunction happens early in the pathological process and does not necessarily follow stage of insulin resistance [29]. Since they retain the ability of secreting some endogenous insulin, they are considered to require insulin but not to depend on insulin. In the progression of disease from normal glucose tolerance to abnormal glucose tolerance, postprandial blood glucose levels are the one which increase first and eventually fasting hyperglycemia also develops as the suppression of hepatic gluconeogenesis fails.
20
Risk factors for Type 2 diabetes mellitus
• Family history of DM
• Obesity
• Race / ethnicity ( Asian American, African American )
• Hypertension
• History of GDM
• HDL less than 35mg% and/or triglyceride more than 250 mg%
• Polycystic ovarian disease
• Emotional stress
• Drugs ( glucocorticoids, estrogens, nicotinic acid)
Genetic Considerations:
Type 2 DM has a strong genetic component. The incidence of type 2 DM in identical twins is about 70 to 90%. Individuals with one parent having type 2 DM have an increased risk of developing diabetes; if both parents have type 2 DM, the risk approaches about 40%. The disease is polygenic and multifactorial in nature.
Since in addition to genetic susceptibility, environmental factors (such as obesity, nutrition and physical activity) also modulate the phenotype. Though genes that predispose to type 2 DM are incompletely identified, a recent genome-wide association studies have identified a large number of genes which convey a relatively small risk for type 2 DM. Most prominent is a variant of the transcription factor 7–like 2 gene that has been linked with type 2 diabetes in
21
several populations and with impaired glucose tolerance in some population at high risk for diabetes[17]. Genetic polymorphisms associated with type 2 diabetes have also been found in the genes encoding the peroxisome proliferators–
activated receptor-γ, zinc transporters and inward rectifying potassium channel, calpain 10. The mechanisms by which these genetic loci increase the susceptibility to type 2 diabetes are not clear till now.
.
Other factors
(a) About 90% of patients who have developed type 2 diabetes mellitus are obese.
However, a large, population-based, prospective study has shown that an energy-dense diet may be a important risk factor for the development of diabetes which is independent of baseline obesity[30]. Compared with persons of European descent, persons of Asian descent are at increased risk for diabetes at lower levels of overweight[31].
(b) There is an increased risk of developing diabetes mellitus in whites when compared with African Americans[32].
(c) Abnormal in utero environment resulting in low birth weight may also lead to type 2 DM.
Hypertension and pre hypertension are often associated with greater risk of predispose some individuals to develop type 2 diabetes mellitus [33-34]. Some forms of diabetes, however, have a clear association with genetic defects. The syndrome which is previously known as maturity onset diabetes of youth (MODY) has now
22
been reclassified as a variety of defects in beta-cell function. These defects account for 2-5% of persons with type 2 diabetes who present at a young age and have a mild disease. The trait is autosomal dominant and can be screened for through commercial laboratories. Till date, 6 mutations have been identified:
HNF-4-alpha Glucokinase gene HNF-1-alpha IPF-1
HNF-1-beta NEUROD1
During the induction of insulin resistance, which is seen after high-calorie diet, steroid administration, or physical inactivity, increased glucagon levels and increased glucose-dependent insulinotropic polypeptide (GIP) levels accompany glucose intolerance; however, postprandial glucagon like peptide-1 (GLP-1) response is unaltered. This has important physiologic implications; for example, if the GLP-1 level is unaltered, GLP-1 may be a target of therapy in the states mentioned above.
Chronic Complications of DM
The chronic complications of DM can affect several organ systems and are responsible for the majority of mortality and morbidity associated with the disease. The risk of chronic complications increases with the duration and also with the degree of hyperglycemia; they usually do not become apparent until the
23
second decade of life in patients with type 1 DM but type 2 DM patients often have complications at the time of diagnosis. Chronic complications can be divided into vascular and nonvascular complications. The vascular complications of DM are further subdivided into microvascular and macrovascular complication.
Though the pathology differs between the different types of diabetes, the complications are similar, including microvascular, macrovascular and neuropathic. Hyperglycemia appears to be the key determinant for the microvascular and metabolic complications. Macrovascular disease, however, is much less commonly related to hyperglycemia but good glycemic control may produce improvement in the lipid profile[95].
Insulin resistance with concomitant lipid abnormalities (elevated levels of small dense low-density lipoprotein cholesterol [LDL-C] particles[42], low high- density lipoprotein cholesterol levels [HDL-C], elevated triglycerides levels) and thrombotic abnormalities (i.e, elevated type-1 plasminogen activator inhibitor [PAI-1], elevated fibrinogen levels), as well as conventional atherosclerotic risk factors (eg, family history, hypertension, smoking, obesity, sedentary lifestyle) determine cardiovascular risk.
Unlike liver and muscle, insulin resistance is not associated with increased myocardial lipid accumulation[35]. Persistent lipid abnormalities remain in patients with diabetes in spite evidence supporting benefits of lipid modifying agents.
Statins and the addition of other lipid-modifying agents are needed[36].
24
Increased cardiovascular risk appears to start earlier to the development of overt hyperglycemia, probably because of the effects of insulin resistance.
Stern[35] in 1996 and Haffner and D'Agostino[36] in 199938developed the "ticking clock" hypothesis of complications, indicating that the clock starts ticking for microvascular risk at the onset of hyperglycemia, while the clock starts ticking for macrovascular risk at some point, presumably with the onset of insulin resistance.
Mechanisms producing chronic complications
Although chronic hyperglycemia is an important risk factor leading to complications of DM mainly the microvascular ones, the mechanisms by which it leads to these varied involvement of multiple organ systems is not fully understood. There are four prominent theories, which have been proposed to explain how hyperglycemia leads to the chronic complications of DM.
(1) Formation of advanced glycosylation end products (AGEs)
It occurs due to the non-enzymatic glycosylation of intra- and extracellular proteins from the complex interaction of glucose with amino groups on proteins.
AGEs have been shown to cross-link proteins (e.g., collagen, extracellular matrix proteins) accelerate atherosclerosis, promote glomerular dysfunction, reduce nitric oxide synthesis, induce endothelial dysfunction, and alter extracellular matrix composition and structure. The serum level of AGEs correlates with the level of hyperglycemia, and these products starts to accumulate as the glomerular filtration rate (GFR) declines.
25
(2) Sorbitol pathway
Hyperglycemia increases glucose metabolism through the sorbitol pathway by the enzyme called aldose reductase. Increased sorbitol concentration alters redox potential, increases cellular osmolality, generates reactive oxygen species, and also leads on to several types of cellular dysfunction. However, using aldose reductase inhibitors has not shown to have significant beneficial effects.
(3) Diacylglycerol pathway
Hyperglycemia increases the production of diacylglycerol leading to activation of protein kinase C which alters the transcription of genes for type IV collagen, contractile proteins, fibronectin and extracellular matrix proteins in endothelial cells and neurons. Inhibitors of PKC are being studied in several clinical trials.
(4) Hexosamine Pathway
Hyperglycemia increases the influx through the hexosamine pathway, which produces fructose-6-phosphate, which may alter function by glycosylation of proteins such as endothelial nitric oxide synthase or by changing the gene expression of transforming growth factor or plasminogen activator inhibitor-1 (PAI-1).
26
Diabetic Retinopathy
DM is one of the leading causes of blindness in India. In India, the prevalence of Diabetic Retinopathy among diabetics is about 17–27%. Prevalence of diabetic retinopathy at the time of diagnosis is about 7.3% [95]. Individuals with DM are 25 times more likely to develop legal blindness than individuals without DM. Diabetic retinopathy is classified into two types:
Figure 5. Diabetic Retinopathy
27
1) Non proliferative diabetic retinopathy
Usually appears late in the first decade or sometimes early in the second decade of the disease and is marked by the appearance retinal vascular micro aneurysms, blot hemorrhages, and cotton-wool spots which progresses to more extensive disease, characterized by changes in venous vessel caliber, intra retinal microvascular abnormalities, and numerous microaneurysms and hemorrhages.
The pathophysiologic mechanisms that are involved in the non proliferative retinopathy include loss of retinal pericytes, increased retinal vascular permeability, alterations in retinal blood flow, and abnormality in retinal microvasculature, all of these eventually leads on to retinal ischemia.
(2) Proliferative diabetic retinopathy
The appearance of neovascularization as a response to retinal hypoxemia is the hallmark finding of proliferative disease. These newly formed vessels appear near the optic nerve and/or macula and rupture easily, leading to vitreous hemorrhage, vitreous fibrosis, and ultimately retinal detachment. Hence it is important to detect it earlier and treat in order to prevent its progression.
Clinically significant macular edema can occur only when non proliferative retinopathy is present. Fluorescein angiography is very useful to detect macular edema, which is associated with 25% chance of having moderate visual loss over a period of next 3 years. Duration of DM and degree of glycemic control are the important predictors for the development of retinopathy.
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Diabetic Nephropathy
Diabetic nephropathy is the leading cause of end stage renal disease (ESRD) and also a leading cause of DM-related morbidity and mortality. Both microalbuminuria and macroalbuminuria in individuals with DM are associated with increased risk of cardiovascular disease. Individuals with diabetic nephropathy concomitantly have diabetic retinopathy also.
The pathogenesis of diabetic nephropathy is often related to chronic hyperglycemia.
The mechanisms by which long standing hyperglycemia lead to end stage renal disease (ESRD) is not fully understood. The probable factors are :
The effects of soluble factors (growth factors, angiotensin II, endothelin, AGEs).
Hemodynamic alterations in the renal microcirculation like glomerular hyperfiltration or hyperperfusion and increased glomerular capillary pressure.
Structural changes in the glomerulus like increased extracellular matrix, basement membrane thickening, mesangial expansion and fibrosis. Smoking accelerates the decline of renal function.
The natural history of diabetic nephropathy is characterized by a predictable sequence of events that was initially defined for individuals with type 1 DM but appears to be similar in type 2 DM as well.
29
Figure 6. Pathophysiology of Diabetic Nephropathy
30
Glomerular hyperperfusion and renal hypertrophy occur during the first years after the onset of DM and are often associated with an increase of the GFR which then return to normal during the first 5 years of DM.
After 5–10 years of type 1 DM, nearly 40% of individuals begin to excrete small amounts of albumin in their urine. Microalbuminuria is defined as 30–299 mg/d in a 24-h collection of urine or 30–299 mg/mg creatinine in a spot ollection.
Though the appearance of microalbuminuria in type 1 DM is an important risk factor for progression to macroalbuminuria (>300 mg/d or > 300 mg/mg creatinine), microalbuminuria is one of the major independent risk factor for cardiovascular disease. Once macroalbuminuria is appears, there is a steady state of decline in GFR, and nearly 50% of these individuals will reach ESRD in 7–10 years. Once macroalbuminuria develops, blood pressure slightly increases and the pathologic changes are likely to be irreversible.
The nephropathy that develops in type 2 DM differs from that of type 1 DM in the following aspects:
(1) Microalbuminuria or macroalbuminuria may be present when type 2 DM is diagnosed, showing its long asymptomatic period.
(2) Hypertension more commonly appears with microalbuminuria /macroalbuminuria in type 2 Diabetes mellitus.
(3) Microalbuminuria is less predictive of diabetic nephropathy and progression to macroalbuminuria in type 2 Diabetes mellitus.
Figurre 7. Histo
31
ology of Diiabetic Nepphropathyy
32
Diabetic Neuropathy
Diabetic neuropathy is seen in 50% of patients with long-standing type 1 and type 2 DM. It may manifest as polyneuropathy, mononeuropathy, and/or autonomic neuropathy. The development of neuropathy often correlates with the duration of diabetes and glycemic control. Both myelinated as well as unmyelinated nerve fibers are affected. Because the clinical features of diabetic neuropathy are similar to those of other neuropathies, the diagnosis of diabetic neuropathy must be made only after other possible etiologies are excluded. It can be of several types.
(1)Polyneuropathy / Mononeuropathy
The most common form of diabetic neuropathy is usually a distal symmetric type of polyneuropathy. It most frequently presents with distal sensory loss, hyperesthesia, paresthesia, and dysesthesia . Neuropathic pain develops in some of these patients typically involves the lower extremities, is usually present at rest, and worsens at night. As diabetic neuropathy progresses, the pain subsides and eventually disappears, but a sensory deficit in the lower extremities persists.
Physical examination also reveals sensory loss, loss of ankle reflexes, and abnormal position sense.
Diabetic polyradiculopathy is a syndrome which is characterized by severe disabling pain in the distribution of one or more nerve roots. It may also be
33
accompanied by motor weakness. Intercostal or truncal radiculopathy causes pain over the thorax or abdomen.
Figure 8. Semmes-Weinstein monofilament
Involvement of the lumbar plexus or femoral nerve may cause severe pain in the hip or thigh and may be associated with muscle weakness in the hip flexors or extensors (diabetic amyotrophy). Diabetic polyradiculopathies are usually self- limited most of the time and resolve over a period of 6–12 months.
Diabetic mononeuropathy is less commonly seen than polyneuropathy in DM and usually presents with pain and motor weakness in the distribution of a single nerve.
34
Involvement of the third cranial nerve is the most common cranial nerve involvement and that is heralded by diplopia. Other cranial nerves including IV, VI, or VII are also affected. Mononeuritis multiplex may also occur with type 2 Diabetes mellitus patients.
(2)Autonomic Neuropathy :
Individuals with long-standing DM can also develop signs of autonomic dysfunction with the involvement of cholinergic, noradrenergic, and peptidergic (peptides such as pancreatic polypeptide, substance P, etc.) systems.
Autonomic neuropathies affecting the cardiovascular system can cause a resting tachycardia and orthostatic hypotension which may be responsible for sudden cardiac death. Gastroparesis, bladder-emptying abnormalities, hyperhidrosis of the upper extremities and anhidrosis of the lower extremities and an inability to sense hypoglycemia appropriately (hypoglycemia unawareness) may also occur with type 2 DM.
Lower Extremity Complications
Diabetes mellitus is one of the leading causes of non traumatic lower extremity amputation. Foot ulcers and infections are also a major source of mortality and morbidity in individuals with diabetes mellitus. The reason for increased incidence of foot ulcers in diabetes mellitus is due to many pathogenic factors including neuropathy, abnormal foot biomechanics, peripheral vascular
35
disease, and poor wound healing. The peripheral sensory neuropathy also interferes with normal protective mechanisms and allows the patient to sustain recurrent minor trauma to the foot, often without knowledge of the injury.
Disordered proprioception leads to abnormal weight bearing while walking and subsequent formation of callus and/or ulceration.
Figure 9. Pathogenesis of Diabetic foot
36
Figure 10. Diabetic foot showing two ulcers
37
Motor and sensory neuropathy lead to abnormal foot mechanics and to structural changes in the foot (hammertoe, claw toe deformity, prominent metatarsal heads, Charcot joint). Autonomic disturbances results in anhidrosis and altered superficial blood flow to the foot, which promote drying of the skin and fissure formation. Peripheral arterial disease and poor wound healing impairs the resolution of minor breaks in the skin, allowing them to enlarge and to become infected.
Approximately 15% of individuals with type 2 diabetes mellitus develop a foot ulcer and a significant subset of people will ultimately undergo amputation (14–24% risk with that ulcer or subsequent ulceration). Risk factors for foot ulcers or amputation include: male sex, diabetes with duration more than10 years, peripheral neuropathy, abnormal structure of foot (bony abnormalities, callus formation, thickened nails), peripheral arterial disease, smoking, history of previous ulcer or amputation and poor glycemic control.
Coronary Artery Disease
Incidence of cardiovascular diseases are increased in individuals with type 1 or type 2 DM[44]. The Framingham Heart Study has revealed a marked increase in the incidence of Coronary artery disease (CAD), Myocardial infarction, Congestive heart failure, Peripheral vascular disease and sudden cardiac death in DM. The American Heart Association has designated DM as a "CHD risk equivalent." Type 2 diabetes patients without a prior MI have a similar risk for
38
coronary artery related events as non diabetic individuals who have had a prior myocardial infarction[47]. CHD is more likely to involve multiple vessels in individuals with diabetes mellitus.
Figure 10b . Myocardial infarction.
The increase in cardiovascular mortality and morbidity rates appears to be due to the synergistic effect of hyperglycemia with other cardiovascular risk factors. Risk factors for macrovascular disease in diabetic individuals include dyslipidemia, hypertension, obesity, decreased physical activity, and cigarette smoking[48].
39
The presence of complications including microalbuminuria, macroalbuminuria, elevated serum creatinine, and abnormal platelet function also play a very important role in the development of macrovascular complications.
Insulin resistance, as marked by elevated serum insulin levels, is often associated with elevated levels of plasminogen activator inhibitors ( PAI-1) and also increased fibrinogen levels which enhances the coagulation process and impairs fibrinolysis thus favoring the development of thrombosis.
Because of the extremely high risk of cardiovascular disease in individuals, any diabetic patient who has symptoms suggestive of cardiac ischemia or peripheral or carotid arterial disease should undergo complete evaluation. The absence of chest pain ("silent ischemia") is common, and so a thorough cardiac evaluation is mandatory when planned for major surgical procedures. In both the DCCT (type1 diabetes) and the UKPDS[95] (type2 diabetes) trials, cardiovascular events were not reduced by intensive treatment during the trial but were reduced during the follow-up period of 10 to 17 years later termed legacy effect or metabolic memory. During the DCCT, an improvement in the lipid profile of individuals in the intensive group (lower total and LDL cholesterol, lower triglycerides) during intensive diabetes management was noted. Other trials
have also failed to show any reduction in cardiovascular morbidity and mortality.
40
Cerebrovascular diseases :
Stroke is one of the major complication that dramatically increases the morbidity and mortality in patients with type 2diabetes mellitus. Diabetes mellitus poses about four folds higher risk for developing stroke. Cardiovascular risk factors including obesity, hypertension, and dyslipidaemia often co-exist in patients with diabetes mellitus that add on to stroke risk. Because of the strong association between diabetes mellitus and other stroke risk factors, physicians managing patients should have thorough understanding of these risk factors and management. Being a disease mainly associated with lifestyle, patients with type 2 diabetes mellitus often have additional risk factors for
41
Figure. 10.C. Computed tomography shows Middle cerebral artery infarct on left side.
stroke including obesity, hypertension and dyslipidaemia that increases the vascular risk in these patients. Type 1 diabetes mellitus (T1DM) also increases the risk of stroke but to a lesser degree. Management of diabetes immediately after a stroke and in the long-term follow up period gives a significant challenges to physicians.
Inappropriate management of diabetes also increases immediate and long- term morbidity and mortality associated with stroke, and significantly increases the risk for recurrent strokes.
42
Worldwide , stroke mortality rates have decreased , but stroke incidence and its complications have significantly increased over the last three decades.
Diabetes is a recognized to be an independent risk factor for stroke and is associated with higher morbidity and mortality. Cardiovascular risk factors including obesity, hypertension, and dyslipidaemia often co-exist with Type 2 diabetes mellitus and can contribute to the increased reported relative stroke risks when compared to patients with similar risk profile without diabetes.
There are clear differences in stroke patterns between patients with diabetes and those without diabetes. Patients with diabetes have a increased proportion of ischemic stroke when compared to haemorrhagic strokes, and lacunar infarcts (i.e., small 0.2 to 15 mm, non cortical infarcts) is the most common stroke pattern. This can be due to the higher prevalence of microvascular disease and the co-existence of hypertension that seen in this patient group.
Prognostic features also differ from normal stroke population as diabetes is associated with an increased risk of subsequent strokes, greater functional disability, longer in-hospital stay, and increased mortality. An increased risk of developing stroke-related dementia has also been reported in many patients.
The occurrence of stroke and its complications are on the rising trend.
Patients with diabetes mellitus are particularly at a higher risk of stroke and have a higher mortality. Starting good glycemic control at first diagnosis of diabetes, irrespective of type, is essential for sustained cardiovascular benefits (i.e.,
43
metabolic memory) and for the reduction of h hyperglycemia-induced pathogenic processes implicated in atherosclerotic disease.
However, long term tight glycemic control has not been shown to improve cardiovascular outcomes and therefore, subsequent management should also focus on modifiable cardiovascular risk factors.
As the population is ageing, the diabetes mellitus in older people is becoming more and more obvious. The economic, physical, medical, nursing, and psycho-social implications of diabetes and stroke will be immense future.
FIBRINOGEN AND DIABETES MELLITUS Introduction
Fibrinogen is one of the important coagulation factors in the final common pathway of coagulation[41]. When fibrinogen is converted to fibrin, it forms a structural meshwork that consolidates an initial platelet plug into a firm hemostatic clot. The physiologic importance of fibrinogen is demonstrated by the bleeding diathesis associated with afibrinogenemia [61,62] and some dysfibrinogenemias[63]. Other dysfibrinogenemias are often associated with thromboembolic disease[63,64] Fibrinogen is a dimeric glycoprotein which is synthesized in the liver and has a molecular weight about 340,000[66]. It is made up of 2 subunits. Each subunit contains three disulfide-linked polypeptide chains[69] referred to as the Alpha (66.5kD), beta(52kD), and γ (46.5kD) chains.
44
Aμ, Bb, and γ are composed of 610, 461, and 411 amino acids, respectively.
Fibrinopeptides A and B are released from the amino-terminal of the alpha and beta chains by thrombin cleavage of the Argl6-
Glyl7 and Argl4-Glyl5 bonds, respectively to form fibrin[70]. The genes for these
45
Figure 11. Normal clotting cascade
46
Figure 12. Fibrinogen in normal clotting mechanism
Three chains of fibrinogen are found within a 50-kb length of DNA on chromosome 4 at q23-q32[71].
It is found in plasma as well as in platelet alpha granules. In the platelets it is taken up from plasma by endocytosis mediated by glycoprotein IIb/IIIa. The plasma half-life of fibrinogen is 3 to 5 days[65].
47
Fibrinogen plays as major role in the following processes.
1. The soluble fibrinogen molecule is converted into an insoluble fibrin during the process of final common pathway of coagulation which stabilizes the initially formed platelet plug.
2. The polymerized fibrin acts as a template for the activation of the fibrinolytic system, which regulates fibrin deposition and clot dissolution.
3. Fibrinogen binds to cells such as platelets and causes platelet aggregation and to the endothelial cells, where it participates in tissue repair.
Hyperfibrinogenemia
Fibrinogen plays a important crucial role in the process of atherosclerosis and thrombosis related phenomenon like hemostasis, inflammation, aggregation of platelets, blood viscosity, smooth muscle proliferation and fibrinolysis.
Although it is considered as a marker of vascular disease, it remains controversial whether fibrinogen is a cause or merely an association with the atherosclerotic process[72]. Fibrinogen is an acute phase reactant, and its synthesis can be increased up to 20-times with a strong inflammatory stimulus[66,67]. IL-6 is an important mediator of increased fibrinogen synthesis during an acute phase response[68] and IL-6 secretion can be up-regulated by fibrin degradation products. Thus, increased fibrinogen levels may be a reflection of the low-grade inflammation associated with vascular disease. On the other hand, increased fibrinogen levels (due to inflammation or other causes) may be responsible for the pathogenesis of certain vascular lesions, acting as a very important risk factor for
48
the atherosclerotic disease and contributes for its progression. Moreover, fibrinogen and fibrin degradation products may enhance the inflammation in the vascular lesions by regulating cytokine mediated action and leukocyte-endothelial interactions[73]. A low grade inflammation secondary to Chlamydia or H.pylori infection have been suggested to increase the fibrinogen levels and thus increase the cardiovascular mortality and morbidity[86]
One of the significant and common conditions that are associated with both elevated fibrinogen level and cardiovascular disease, are type 2 diabetes mellitus[46] and the insulin resistance syndromes[74,75]
The mechanisms which lead to hyperfibrinogenemia in type 2 diabetes mellitus have not been elucidated so far clearly. The potential mechanisms which are suggested include that of a low grade inflammation, hyperinsulinemia and albuminuria[76-78] Zanetti et al and Schrem et al have suggested the following mechanism :
In diabetes, patients develop albuminuria which leads to hypoalbuminemia leading to decrease in plasma oncotic pressure which in turn stimulates hepatic protein synthesis. Although there is increased synthesis of all plasma proteins, the synthesis of fibrinogen is increased to a greater extent associated with a decreased clearance and this increased levels of fibrinogen is responsible for cardiovascular adverse effects[77,82]
49
Others have reported that fibrinopeptide is positively related to glucose homeostasis and this is probably how hyperglycemia leads to elevated fibrinogen levels[83,84]. There is also controversy whether elevated fibrinogen levels are a consequence of diabetic nephropathy and subsequent loss of albumin or nephropathy[53,54] is being worsened by elevated fibrinogen.
Researchers have proposed that there is existence of “insulin resistance genes” which may be responsible for insulin resistance as well as hyperfibrinogenemia[79]. The putative genes include Lipoprotein lipase gene and the fibrinogen gene[81,82]
Multiple factors have been found to affect fibrinogen levels. It increases with age, body mass index, smoking, and post menopause, low-density- lipoprotein (LDL) cholesterol, lipoprotein (a) and leukocyte count. It decreases with physical activity[87], moderate alcohol intake88], increased high-density- lipoprotein (HDL) cholesterol, and also with hormone replacement therapy (HRT)[89-90]. Higher levels of plasma fibrinogen were also seen in non-drinkers or who drank > 60 g of alcohol per day[88].
Interventions to lower fibrinogen levels
Lifestyle modifications found to alter fibrinogen level, of which smoking cessation is by far the most effective one[91]. Weight or stress reduction or an increase in regular physical activity has less effects; dietary modifications seems
50
to have even less effect, moderate alcohol consumption causes a small reduction[93].
Among the oral fibrinogen reducing medications, fibrates (e.g. Bezafibrate reduces increased fibrinogen by around 40%), and Ticlopidine (reduces about 15%) are effective only if fibrinogen levels are increased. The efficacy of these drugs when the fibrinogen levels are normal has not been fully evaluated. Finally, intravenous fibrinolytic agents or heparin-induced extracorporeal low-density lipoprotein precipitation will also lower the fibrinogen levels dramatically; but still these methods are not indicated for this purpose alone and needs further studies[93].Aspirin in low doses has no significant influence on plasma fibrinogen levels[91]. Eriksson at al in a study involving 292 women found that the levels of fibrinogen were elevated in post menopausal women than pre menopausal women and in women not taking any hormone replacement therapy than in women taking Hormone Replacement therapy[43]. Thus Hormone replacement therapy (HRT) has a beneficial effect in lowering fibrinogen. Different antihypertensive drugs elicit different effects on fibrinogen and lipid profile, which has varying influence on the overall risk profile of these patients.
Patients who were on ‘lipid-neutral such as ACE-I, Ca-blocker, Angiotensin-II blocker or lipid friendly (alpha-blocker) anti-hypertensive drugs had significantly lower plasma fibrinogen levels, when compared with those who were on ‘lipid hostile’ drugs (Beta-blocker, Thiazide diuretic) [98].
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A study has shown that elevated plasma fibrinogen (≥375 mg/dl) in the presence of diabetes mellitus and increased BMI (≥25 kg/m2) are often associated with lower platelet inhibition with Clopidogrel in patients with cardiovascular diseases[94].
In a study by Zhao et al involving 1300 Chinese diabetic subjects it was found that APTT values decreased and fibrinogen levels increased with increasing HbA1c values and they recommended APTT and fibrinogen tests may be used as potential screening tests for thrombotic complication risk in Type 2 DM patients[97].
To conclude physiological importance of elevated plasma fibrinogen levels is not fully understood. There are several mechanisms by which fibrinogen can be involved in atherothrombosis. It may be due to rheological alterations, increased platelet aggregability, increased fibrin formation, and stimulation of vascular cell proliferation and migration. Still the association between fibrinogen and cardiovascular risk does not establish a cause-effect relation. Elevated fibrinogen levels, whatever the cause may be like genetic, inflammation or some other reason may cause a hypercoagulable state that could produce various adverse effects[92].
These adverse effects are much more pronounced in diabetes mellitus.
MATERIALS AND
METHODS
52
MATERIALS AND METHODS
SOURCE OF DATA :
The study was conducted on patients with newly detected type 2 diabetes mellitus admitted in medical / diabetology ward and attending outpatient department at Rajiv Gandhi Government General Hospital.
STUDY DESIGN :
Observational case control study
STUDY CENTRE:
Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai.
DURATION OF STUDY:
One year.
SAMPLE SIZE :
50 cases , 50 controls
53
Inclusion criteria for the cases :
• Age : 25 to 60 years
• Sex: Both Male and Female
• Patients with newly detected Type 2 Diabetes mellitus according to ADA guidelines.
• Patients willing for the study
Exclusion criteria for the cases :
• Patient not willing for study
• Patient <25 years of age and >60years of age.
• Known case of Type 2 Diabetes mellitus on treatment.
• Known case of TYPE 1 Diabetes mellitus.
• Pregnancy, ICU Patients, Post operative patients.
• Known case of bleeding diathesis.
• Previous history of thrombotic events ( DVT, pulmonary embolism, Cortical vein thrombosis)
• Known case of Coronary artery disease, cerebrovascular accident, chronic kidney disease.
• History of malignancy, Autoimmune disorder, Infection
54
Inclusion criteria for the controls : Age : 25 to 60 YEARS
Individuals with normal glycemic control.
Participants willing for the study.
Exclusion criteria for the controls :
Acute or chronic illnesses on treatment.
Age : Less than 25 and more than 60 Persons not willing for the study.
LAB INVESTIGATIONS :
1) Fasting and post prandial blood glucose levels 2) HbA1C using H.P.L.C Method.
3) Plasma fibrinogen levels 4) Complete blood counts 5) Coagulation profile 6) Electrocardiogram
55
METHODOLOGY:
• A total of 100 participants ( 50 cases and 50 controls ) were included in this study including both males and females ranging from the age 25 to 60 years.
• All participants are subjected to thorough history and clinical examination.
• Fresh peripheral venous blood sample of about 2ml is collected in serum tubes and dispatched for blood glucose levels (Fasting / post prandial / random blood sugar) analysis.
• Fresh peripheral venous blood of about 2 ml collected in serum test tube and dispatched for assessment of serum fibrinogen level based on
electromagnetic viscosity measurement method.
• The data are then analysed and appropriate statistical analysis is carried out.
OBSERVATION AND
RESULTS
56
OBSERVATIONS AND RESULTS
FREQUENCY TABLE
Table 1. Age wise frequency distribution
AGE GROUP FREQUENCY PERCENTAGE
25-30 YEARS 4 4%
31-40 YEARS 16 16 %
41-50 YEARS 50 50 %
50 – 60 YEARS 30 30%
57
For Cases
Table 2 . Plasma fibrinogen among males and females in cases
314.32 306.63
0 50 100 150 200 250 300 350
Male Female
PLASMA FIBRINOGEN mg/dl
GROUP STATISTICS
Sex N Mean Std.
Deviation
Std. Error Mean
t value p value Plasma
Fibrinogen (mg/dl)
Male 31 314.3226 45.66938 8.20246 0.629 0.532 Female 19 306.6316 34.87153 8.00008 0.532
58
For control GROUP STATISTICS
SEX N Mean Std.
Deviation
Std.
Error Mean
t value
p value
Plasma fibrinogen (mg/dl)
Male 28 248.4643 38.83820 7.33973 0.753 0.455 Female 22 240.5000 34.75321 7.40941
Table 3 . Plasma fibrinogen among males and females in controls.
248.46 240.5
0 50 100 150 200 250 300
Male Female
PLASMA FIBRINOGEN mg/dl
Ta
Age group
Total Pearso
able 4 . Per
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
50%
2
p
25-3 Yea 31-4 Yea 41-5 Yea 51-6 Yea l
on Chi-Squ
rcentage d
20-30 Years 4% 4%
30 ars
Coun
% wit 40
ars
Coun
% wit 50
ars
Coun
% wit 60
ars
Coun
% wit Coun
% wit uare=1.533
distribution
31-40 20%
59
CROSST
nt
thin group nt
thin group nt
thin group nt
thin group nt
thin group 3 p=0.675
n of age am
Years
%
12%
Cases C
TAB
Gr Cases
2 4.0%
10 20.0%
25 50.0%
13 26.0%
50 100.0%
mong case
41-50 Years 50% 50%
Control
roup Control
2 2
% 4.0%
0 6
% 12.0%
5 25
% 50.0%
3 17
% 34.0%
0 50
% 100.0%
es and con
s 51-6
26
%
Total l
2 4
% 4.0%
6 16
% 16.0%
50
% 50.0%
7 30
% 30.0%
0 100
% 100.0%
ntrols.
60 Years 6%
34%
