White blood cell count is associated with macro- and microvascular complications in Chinese patients with type 2 diabetes

OBJECTIVES - There are close associations among raised white blood cell (WBC) count, coronary heart disease, and metabolic syndrome in the general population. The association between WBC count and vascular complications of diabetes has not been explored. We carried out a cross-sectional cohort study to determine the association between WBC count and the presence of macro- and microvascular complications in type 2 diabetes. RESEARCH DESIGN AND METHODS in this study, 3,776 patients with type 2 diabetes and normal WBC count (3.5-12.5 X 10(9)/l) underwent a comprehensive assessment of complications and cardiovascular risk factors based on the European DiabCare protocol. Demographic and anthropometric parameters were recorded. Metabolic profiles, including complete blood picture and urinary albumin excretion, were measured. RESULTS - Patients with higher WBC counts (categorized into quintiles) had adverse metabolic profiles as evidenced by higher blood pressure, BMI, HbA(1c), fasting plasma glucose, LDL cholesterol, triglycerides, and urinary albumin excretion, but lower HDL cholesterol (all P <0.001 for trend). The prevalence of macro- and microvascular complications increased in a dosage-related manner with WBC count. After adjustments for smoking and other known cardiovascular risk factors, a 1-unit (1 X 10(9)/l) increment of WBC count was associated with a 15.8% (95% CI 9.3-22.61 P < 0.001) and 12.3% increase (5.8-19.1, P < 0.001) in the prevalence of macro- and microvascular complications, respectively. CONCLUSIONS - Elevated WBC count, even within the normal range, is associated with both macro- and microvascular complications in type 2 diabetes. Chronic inflammation, as indicated by a. higher WBC count, may play a linkage role in the development of macro- and microvascular complications in diabetes.