Objective: To examine different clusterings of the insulin resistance-associated cardiovascular risk factors with respect to different types of obesity.
Design: A screening programme for obesity (body mass index; BMI> or =30 kg/m2) and abdominal adiposity (waist-to-hip ratio; WHR > or = 1.00 in men and > or = 0.88 in women).
Settings: Pieksämäki District Health Centre and the Community Health Centre of the City of Tampere, Finland.
Subjects: All volunteers were either aged 36, 41, 46 or 51 y (n=1148) and living in the town of Pieksämäki, with a control population of 162 subjects in the City of Tampere.
Main outcome measures: Different clusterings of: 1) hypertension (a systolic blood pressure > or = 160 mmHg and/or a diastolic blood pressure > or = 95 mmHg or concurrent drug treatment for hypertension); 2) hypertriglyceridaemia > or = 1.70 mmol/l; 3) a low level of high-density-lipoprotein (HDL) cholesterol; < 1.00 mmol/l in men, < 1.20 mmol/l in women; 4) abnormal glucose metabolism (impaired glucose tolerance or non-insulin-dependent diabetes) and 5) hyperinsulinaemia with a fasting plasma insulin > or = 13.0 mU/l.
Results: The prevalence of a cluster consisting of dyslipidaemia (hypertriglyceridaemia and/or low HDL-cholesterol) and insulin resistance (abnormal glucose metabolism and/or hyperinsulinaemia) was found to be 4% in the control subjects, 18% in the abdominal adipose subjects (WHR > or = 1.00 in men and > or = 0.88 in women with a BMI < 30 kg/m2), 28% in the 'pure' obese subjects (BMI> or = 30 kg/m2 with WHR < 1.00 in men and < 0.88 in women), and 46% in the central obese subjects (subjects showing both 'pure' obesity and abdominal adiposity). The prevalence rates of the other clusterings of abnormalities varied similarly according to the type of obesity.
Conclusion: Clusterings of insulin resistance-associated abnormalities were related to the type of obesity in both middle-aged men and middle-aged women.