Effect of Smoking on the Prevalence of Insulin Resistance-Associated Cardiovascular Risk Factors Among Finnish Men in Military Service

Abstract

Background Obesity, central obesity, hypertension, dyslipidemia and hyperinsulinemia tend to cluster in the same individuals as a metabolic syndrome; smoking has an adverse effect on insulin resistance. The aim of our study was to examine the occurrence of clusters of insulin-resistance-associated abnormalities and the effect of smoking on this clustering in young men.

Methods In 1995 we invited all the 1268 servicemen attending military service in the Ostrobothnian Brigade, Finland, for screening of the metabolic syndrome. The first phase consisted of an interview concerning smoking and measurements of blood pressure, weight, height, waist and hip circumferences. If diastolic pressure was > 85 mmHg, body mass index > 27 or waist-to-hip ratio > 0.98, these participants were invited to blood samples for the measurements of fasting serum lipids, plasma glucose and insulin. These results were obtained from 144 screening-positive men (12%) and from their 79 (7%) randomly selected controls.

Results The metabolic syndrome, defined as plasma insulin ≥ 13.0 mU/l and serum triglycerides ≥ 1.70 mmol/l and/or total cholesterol/high-density lipoprotein cholesterol > 5.0, was present in 10% (n = 14) of the screening-positive participants. None of the randomly selected controls had the metabolic syndrome. The metabolic syndrome was present in 12% (n = 11) of 93 smokers and in 2% (n = 3) of 128 non-smokers (P = 0.004).

Conclusions We conclude that clusters of metabolic abnormalities associated with insulin resistance are already present in young men, and that the prevalence of these clusters in smokers is sixfold compared with non-smokers.