Key words: diabetes mellitus, metabolism, cross sectional studies, metabolic syndrome.

According to the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults in USA. Adult Treatment Panel III (ATP III)1,2, MetS (formerly called syndr ome X, insulin resistance syndrome, dysmetabolic syndrome, cardiovascular multiple metabolic syndrome, multiple metabolic syndrome or cardio-metabolic syndrome) was defined, as when three or more of the following abnormalities are present, which are: abdominal obesity (AO) with waist circumference for men >102 cm and women >88 cm, serum triglycerides (TG) =150 mg/dl (= 1.7 mmol/l), high density lipoprotein (HDL) cholesterol for men <40 mg/dl ( < 0.9 mmol/l , and for women <50 mg/dl (< 1.0 mmol/l), blood pressure =130/85 mmHg, and fasting plasma glucose =110 mg/dL(6.1 mmol/l).

The syndrome iis not new, having been already observed in 1923 by Kylin, who described the clustering of hypertension, hyperglycemia, and gout as a syndrome.3

MetS increases the risk for coronary heart disease and stroke by three fold with marked increase in cardiovascular mortality.4

The aim of the study is to assess the prevalence of MetS in patients with type 2 diabetes mellitus (DM) according to the definition of the ATP III report.

This was a cross sectional hospital based study of patients with type 2 DM. It includes patients with type 2 DM seen in the in-patient and out-patient clinic of the Basrah Military hospital over a peroid from Jan 2002 to October 2002. All patients with type 2 DM, regardless of the duration of DM, were included if they agreed to particpate in this study.

The new type 2 DM was diagnosed according to the American Diabetic Association (ADA) recommendations in 2002.5 Patients who were currently on drug treatment for diabetes and hypertension were considered hypertensive and diabetic respectively. For blood pressure, the average of second and third blood pressure measurements in the office were considered. Two blood pressure recordings were obtained from the right arm of patients in a sitting position after 30 minutes of rest at 5-min intervals, and their mean value was calculated.

The women were non-pregnant, and the blood estimation of lipoprotein was taken after at least an 8 hour fast. Diabetes duration ranged from a few days to 30 years.

Since all of our patients were diabetics, the presence of 2 metabolic abnormalities other than DM, is enough to establish the diagnosis of MetS.

The waist circumference was measured with a soft tape on standing subjects, midway between the lowest rib and the iliac crest.1

Total number of patients was 200. Of these 145 were males and 55females. Age range was 28-88 years, and mean age 51.9±10.6 years. Overall MetS (Table 1) was seen in 86% (82.7% of males and 94.5% of females).

Prevalence of different metabolic abnormalities are presented in Table 2. At least 2 metabolic abnormalities were seen in 32.5% of patients.

In Table 3, hypertension was the commonest metabolic abnormality (76.5%) followed by high TG (69%).

The commonest combinations that constitute the MetS with diabetes (Table 4) were Hypertension, abdominal obesity, low HDL and High TG in 26.5%.

An array of metabolic, hemodynamic, and renal abnormalities constitutes the cardiometabolic syndrome. A hallmark of this syndrome is visceral obesity and associated insulin resistance/hyperinsulinemia. The syndrome is also associated with essential hypertension, abnormalities in the circadian rhythm of blood pressure and heart rate, the diabetic dyslipidemic syndrome, hypercoagulability, hyperuricemia, increased cardiovascular inflammation, and microalbuminuria, all of which contribute to an increased risk of cardiovascular disease morbidity and mortality.2,6-8

Insulin resistance may be the underlying feature of MetS .9 The World Health Organization( WHO) definition of MetS in 199810 is different from that of AHA and ATP III1, where the WHO defined the MetS as presence of at least two of the following 1) hypertension, defined as antihypertensive treatment and/or elevated blood pressure ( > 160 mmHg systolic or > 90 mmHg diastolic); 2) dyslipidemia, defined as elevated plasma triglyceride { = 1.7 mmol/l(150 mg/dl)} and/or low HDL cholesterol {< 0.9 mmol/l in men(40mg/dl), < 1.0 (50 mg/dl)mmol/l in women} concentrations; 3) obesity, defined as a high BMI ( =30 kg/m 2 ) and/or a high WHR ratio ( > 0.90 in men, > 0.85 in women); and 4) microalbuminuria (urinary albumin = 20 µ g/min). We chose the ATP III definition, because it is easier as we have difficulity in measuring microalbuminuria in our area and even some questioned the value of the last WHO criteria because of its rarity.11,12

In this study we reported the highest prevalence of MetS reported in literature ,which was 86% (82.7% of males and 94.5% of females). The prevalance of MetS among patients with type 2 DM according to WHO definition for women and men respectively was 84 % and 78%, in Botnia study ( ~ 80% for both sexes) in Finland and Sweden.4 In USA, MetS among adults was seen in 6.7% to 42% according to age (increase with age), with an age adjusted rate of 23.7%.13 In Saudi patients MetS is seen in 56% of patients with Type 2 DM and the commonest component of the syndrome was hypertension . 14

For all studies MetS was more common in females females than males. In this study, hypertension is again the commonest metabolic abormality and the commoenst constellation of metabolic abnormalities were hypertension, abdominal obesity, low HDL and high TG. One explanation of this high rate of MetS in this study is adoption of Western lifestylein our society with overweight, physical inactivity, sedentary behaviour, and unhealthy dietary habits (non healthier lifestyle).

The prevalence of the MetS and its components is strongly dependent on the definition of the different components of the syndrome,which is still not accepted for all globally.2,4,11,13,15

In conclusion the highest prevalence of MetS was reported in this study, which includes diabetic patients only, although this high figure may be due to different definitions and population studied with selection bias.13 These figures seem alarming if no prevention protocol is adopted.The mainstay of management of MetS is dietary modification and weight reduction which may delay the development of DM, improves the control of established DM and decreases morbidty and mortality associated with this syndrome.1 Further studies including all people whether diabetic or not, is mandatory to estimate the prevalence of MetS.

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2. Enzo Bonora, Stefan Kiechl, Johann Willeit, et al. Prevalence of Insulin Resistance in Metabolic Disorders.The Bruneck Study.Diabetes 1998; 7:1643-1649.
   
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