Gender Differences in Adiponectin and Low-Grade Inflammation Among Individuals With Normal Glucose Tolerance, Prediabetes, and Type 2 Diabetes

Background: Women with prediabetes and type 2 diabetes mellitus have a higher relative risk of cardiovascular disease than do men. The reason for this is unknown. Objective: We studied the gender differences in adiponectin and in low-grade inflammation, measured by high-sensitivity C-reactive protein (hs-CRP) and interleukin-1 receptor antagonist (IL-1RA), in individuals with normal glucose tolerance, prediabetes, and type 2 diabetes. Methods: In this population-based, cross-sectional study, all individuals born in 1942, 1947, 1952, 1957, and 1962 in Pieksamaki, East Finland, were recruited for participation. A 75-g oral glucose tolerance test and lipid panel were performed, and concentrations of adiponectin, hs-CRP, and IL-1RA were measured. The World Health Organization diagnostic criteria for diabetes and prediabetes (impaired fasting glucose and/or impaired glucose tolerance) were used. Statistical comparisons between men and women were performed by a bootstrap-type ANCOVA. Results: The eligible population included 1.294 middle-aged individuals, and of these, 904 (406 men and 498 women) had complete data and were included in the analyses. Absolute adiponectin concentrations were significantly higher in women at all levels of glucose tolerance (normal, prediabetes, and type 2 diabetes), but the gender ratio (women to men) for adiponectin concentrations decreased linearly (P = 0.011) from normal glucose tolerance (1.61; 95% CI, 1.48-1.75) to prediabetes (1.57; 95% CI, 1.36-1.83) and diabetes (1.16; 95% CI, 0.87-1.53). Among participants with normal glucose tolerance, no significant difference was found between the sexes in hs-CRP or IL-1RA. Among patients with prediabetes or diabetes, women had significantly higher concentrations than did men for hs-CRP (for prediabetes, 2.0 vs 1.5 mg/L; ratio, 1.39; 95% CI, 1.04-1.85) and IL-1RA (for prediabetes, 255 vs 178 pg/mL; ratio, 1.43; 95% CI, 1.12-1.83). The gender ratios (women to men) increased linearly from normal glucose tolerance to prediabetes and type 2 diabetes for both hs-CRP (P = 0.019) and IL-1RA (P = 0.013). Conclusions: Adiponectin concentrations in women decreased relatively more compared with men across individuals with normal glucose tolerance, prediabetes, and type 2 diabetes, whereas inflammatory markers increased relatively more in women. Higher inflammatory stress in women than in men with prediabetes and type 2 diabetes may explain their relatively higher cardiovascular disease risk. (Gend Med. 2009;6:463-470) (C) 2009 Excerpta Medica Inc.