Obesity and risk of hypercholesterolemia in Iranian northern adults

BACKGROUND: The main aim of this study was to evaluate the association between serum cholesterol level and body mass index (BMI) in northern Iran. METHODS: This was a cross-sectional study carried out on the ۱۹۹۵ subjects (۹۹۷ males and ۹۹۸ females) aged ۲۵-۶۵ years that were selected using multistage cluster sampling method. Plasma cholesterol was measured in the morning after a ۱۲-hour fasting and was determined by auto-analyzer. Hypercholesterolemia (HC) was defined by a total plasma cholesterol level over ۲۰۰ mg/dl. Weight and height were measured and BMI ۲۵-۲۹.۹ kg/m۲ and ≥ ۳۰ kg/m۲ was classified overweight and obesity, respectively. RESULTS: Mean of age was ۴۴.۲ ± ۱۱.۵ years (۴۴.۳ ± ۱۱.۵ in men and ۴۴.۱ ± ۱۱.۲ in women) and plasma total cholesterol level was ۲۰۳.۱ ± ۴۱.۸ mg/dl. The HC was detected in ۴۹.۱% with higher rate in women (۵۷.۰%) than men (۴۴.۷%). In men at age ۲۵-۳۵ years, the odds ratio was ۳.۴۲ (۱.۶۰-۷.۲۹) in obese group and ۱.۹۰ (۱.۰۳-۳.۵۰) in overweight group compared to normal weight. In women, at age ۳۵-۴۵ years, the risk of HC in obese group was ۳.۰۱ (۱.۵۸-۵.۷۳) and in overweight group it was ۲.۰۶ (۱.۵۸-۵.۷۳), while in men aged ۳۵-۴۵ years the relative risk was ۴.۰۳ (۲.۲۲-۷.۳۴) in overweight and ۳.۵۸ (۱.۷۷-۷.۲۵) in obese group. In women after age ۴۵ years, higher BMI was not a risk factor for HC. CONCLUSION: There was a positive association between BMI and serum cholesterol level. In early middle age, obese individuals were at risk of HC more than overweight subjects. In men, after age ۳۵ years, the risk of HC increased in overweight group while in women there was no statistically significant association between BMI and HC.   Keywords: Serum Cholesterol Level, Adult, Body Mass Index, Gender, Iran