White Blood Cell Count and the Risk of Hyperglycemia according to Smoking Status

ABSTRACT

BACKGRUOND Recently, inflammation has been associated with insulin resistance and the development of type 2 diabetes mellitus. We investigated the relationship between white blood cell (WBC) count and the incidence of hyperglycemia and the interactive effects of smoking and elevated WBC count on hyperglycemia. METHODS: We prospectively examined 6,734 Korean males without IFG (fasting plasma glucose concentration of > or = 110 mg/dL) or type 2 diabetes mellitus from 1994 to 2002. We divided WBC counts into 4 groups 2.9~5.9 (reference quartile), 6.0~6.9, 7.0~8.1, 8.2~16.5 (x10(3) cells/microliter), respectively. The odds ratios were calculated by multiple logistic regression according to WBC quartiles after adjusting for predictive risk factors of type 2 diabetes mellitus. Also the odds ratios were calculated after stratification according to smoking status. RESULTS: Compaired to reference quartile, the odds ratio for hyperglycemia was 1.09 (95% CI, 0.91~1.30), 1.17 (95% CI, 0.99~1.40), 1.34 (95% CI, 1.12~1.60) (P value for trend=0.0009), respectively. And the odds ratio for IFG or type 2 diabetes mellitus was 1.08 (95% CI, 0.83~1.42), 1.16 (95% CI, 0.89~1.50), 1.28 (95% CI, 1.00~1.65) (P value for trend=0.0395) among the current smoking group, respectively. CONSLUSION Our findings demonstrate that an elevated WBC count is associated with an increased risk of hyperglycemia, particularly in current and former smokers. These results support our hypothesis that inflammation increases the risk of hyperglycemia.