Published online Oct 15, 2013. doi: 10.4239/wjd.v4.i5.219
Revised: August 16, 2013
Accepted: August 28, 2013
Published online: October 15, 2013
AIM: To investigate whether serum adiponectin protects against cardiometabolic risk in a population sample with prevailing metabolic syndrome.
METHODS: Middle-aged adults representative of a general population with baseline circulating adiponectin measurements (n = 1224) were analyzed prospectively at a mean of 3.8 years’ follow-up, using continuous values or sex-specific tertiles. Total adiponectin was assayed by an ELISA kit. Type-2 diabetes was identified by criteria of the American Diabetes Association. Hypertension was defined as a blood pressure ≥ 140 mmHg and/or ≥ 90 mmHg and/or use of antihypertensive medication. Outcomes were predicted using Cox proportional hazards regression analysis in models that were controlled for potential confounders.
RESULTS: In models of multiple linear regression, sex hormone-binding globulin, fasting insulin (inverse) and, in men, age were significant independent covariates of serum adiponectin which further tended in women to be positively associated with serum creatinine. Cox regression analyses for incident coronary heart disease (CHD), adjusted for sex, age, non-HDL cholesterol, waist circumference and C-reactive protein, revealed significant inverse association with adiponectin tertiles in men but not women (HR = 0.66; 95%CI: 0.32-1.38 for highest tertile). Cox regression for type-2 diabetes in a similar model (wherein glucose replaced non-HDL cholesterol), adiponectin tertiles appeared to protect in each gender. HR for incident hypertension roughly displayed unity in each of the adiponectin tertiles (P-trend = 0.67).
CONCLUSION: High adiponectin levels failed to protect against the development of hypertension and, in women, against CHD, presumably paralleling impairment in renal function as well. Involvement of adiponectin in autoimmune complex with loss of antioxidative-antiatherogenic properties may be underlying.
Core tip: The issue of whether serum adiponectin protects against cardiometabolic risk in people prone to metabolic syndrome was studied in 1224 Turkish adults at a mean of 3.8 years’ follow-up. High adiponectin levels were surprisingly positively associated independently with serum creatinine in women and further failed to protect against the development of hypertension in both sexes. In multivariable adjusted Cox proportional hazards regression analyses, protection against type-2 diabetes was apparent, but women were not protected against incident coronary heart disease by high serum adiponectin. Involvement of circulating adiponectin in autoimmune complex with loss of mainly antioxidative properties may be underlying.