THE WHITE BLOOD-CELL COUNT - ITS RELATIONSHIP TO PLASMA-INSULIN AND OTHER CARDIOVASCULAR RISK-FACTORS IN HEALTHY MALE INDIVIDUALS

Objectives. To evaluate the relationships of total and differential wh ite blood cell (WBC) count to the components of the so-called insulin resistance syndrome. Subjects and design. The study population consist ed of a random sample of 90 38-year-old healthy men with normal glucos e tolerance. Interventions. A 75 g oral glucose tolerance test was per formed in all participants. Main outcome measures. Total and different ial WBC count, lipids, blood pressure, plasma glucose, C-peptide and i nsulin (at fasting and 2 h after glucose load). Results. Total WBC cou nt correlated consistently with plasma 2-h glucose (r = 0.38; P < 0.00 1), fasting and 2-h postload insulin (r = 0.26 and r = 0.33; P < 0.01- 0.001, respectively) and C-peptide (r = 0.28 and r = 0.32: P < 0.01-0. 001) concentrations. Smokers had significantly higher total leukocytes (P < 0.01), neutrophils and lymphocytes than nonsmokers. Furthermore, total WBC count correlated positively with body mass index, blood pre ssure, plasma triglycerides, fibrinogen, and negatively with HDL chole sterol concentration. As differential WBC count, most variables correl ated essentially to neutrophils and/or lymphocytes, whereas plasma ins ulin and C-peptide concentrations correlated essentially to lymphocyte s and monocytes, but not to neutrophils. In a multiple linear regressi on analysis, only 2-h plasma glucose (P < 0.01) and fibrinogen (P < 0. 05) were positive predictors of total WBC count after adjusting for al l potentially confounding variables. Conclusions. The results indicate that increased, albeit normal, WBC count associates with the cluster of metabolic and haemodynamic disorders typical of the insulin resista nce syndrome, and suggest that increased WBC count may be yet another component of this syndrome.