Hyperinsulinemia and clustering of cardiovascular risk factors in middle-aged hypertensive Finnish men and women

OBJECTIVE: To examine the relationship between hyperinsulinemia and clusters of cardiovascular risk factors in middle-aged hypertensive patients. DESIGN: A population-based study. SETTING: Pieks?m?ki District Health Center, and the Community health Center of the city of Tampere, in central Finland. SUBJECTS: Hypertensive men and women aged 36, 41, 46, and 51 years (n = 18) in the town of Pieks?m?ki, and a normotensive control population of 177 subjects aged 40 and 45 years in the city of Tampere. MAIN OUTCOME MEASURES: Clusters of obesity (body mass index > 30.0 kg/m2), abdominal adiposity (waist:hip ratio > 1.00 for men and > 0.88 for women), hypertriglyceridemia (> 1.70 mmol/l), a low level of high-density lipoprotein cholesterol (< 1.0 mmol/l in men and < 1.20 mmol/l in women) and abnormal glucose metabolism (impaired glucose tolerance or noninsulin-dependent diabetes as defined by World Health Organization criteria) according to statistical quartiles of the fasting plasma insulin concentration. RESULTS: Among the hypertensives, there was a 2.0- to 3.6-fold higher risk of having a clustering of the insulin-resistance associated cardiovascular risk factors compared with that of the normotensives. Among the hypertensive subjects in the highest quartile of fasting plasma insulin there was a six- to 12-fold increase in risk associated with having two or more insulin resistance-associated cardiovascular risk factors compared with the subjects in the lowest quartile. There was a positive correlation between a high number of ascertained risk factors and high levels of fasting plasma insulin. CONCLUSION: In clinical practice, knowledge of the close relationship between risk-factor cluster status and fasting plasma insulin levels offers a tool to evaluate the occurrence of hyperinsulinemia in middle-aged hypertensive men and women.