The National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) (1) defined metabolic syndrome as a presence of any three of the following (in women): 1) waist circumference >88 cm, 2) high triglycerides (≥150 mg/dl), 3) low HDL cholesterol (<50 mg/dl), 4) high blood pressure (≥130/85 mmHg or use of antihypertensive therapy), and 5) high fasting blood glucose (≥110 mg/dl). This clustering of risk factors in metabolic syndrome ultimately leads to diabetes and premature cardiovascular disease (2). It is imperative to identify individuals with metabolic syndrome early so that lifestyle interventions and treatment may prevent the development of diabetes and/or cardiovascular diseases. The aim of this study was to determine the prevalence of metabolic syndrome in a rural sample of women because such data are not available.
This study was done in 2001 in Ekhlaspur, a village of Chandpur district. There were 1,350 women aged ≥18 years in Ekhlaspur. We randomly invited 375 women, and 314 (84%) of them responded. All participants gave informed consent. Blood pressure was measured twice on the right arm while in the seated position, at least 2 min apart, with the average being used for analysis. Waist circumference was measured midway between the iliac crest and costal margins after removing folds of clothing. Plasma triglycerides and glucose were measured on fasting venous blood samples by using an autoanalyzer.
The average age of our subjects was 39 ± 15 years (mean ± SD), with a median schooling of 4 years. As per the NCEP ATP III (1) definition, the prevalence of metabolic syndrome varied depending on combinations: 1.3% for abdominal obesity plus high levels of plasma glucose and triglycerides, 1.6% for abdominal obesity plus high levels of blood pressure and plasma glucose, and 2.9% for abdominal obesity plus high levels of blood pressure and plasma triglycerides. These prevalences were largely age dependent. Women aged ≥45 years had a prevalence of metabolic syndrome that was three to six times higher than their younger counterparts. This may be due to menopause and low level of physical activity in the elderly women.
The present study describes population prevalence of metabolic syndrome in Bangladesh for the first time. The prevalence observed is relatively low (<3%). This is contrary to that suggested by studies on Bangladeshi immigrants to the U.K. (3). The low prevalence occurred despite the fact that a large proportion (65%) of women had low HDL cholesterol level. This may indicate a low tendency for the clustering of traits. Higher prevalence of insulin resistance in immigrants may be due to unfavorable environmental triggers such as stress, physical inactivity, and smoking (3).
Physical activity level in this agricultural population is high because of their traditional lifestyle. Regular physical activity reduces obesity, increases HDL cholesterol, and decreases triglycerides (1). Smoking may lead to insulin resistance and abdominal obesity (4). It is also well known that smoking elevates triglycerides and lowers HDL cholesterol. Smoking is almost absent (0.3%) in our sample. The combined effect of good physical activity level and a very low prevalence of smoking may partly explain the observed low prevalence of metabolic syndrome in this rural population of Bangladesh. Studies in urban populations are necessary.
