Objective: To investigate the associations between obesity-predisposing genetic variants, cardiovascular biomarkers, and cardiovascular disease (CVD) risk in women with preexisting type 2 diabetes mellitus.
Methods and results: We genotyped polymorphisms at nine established obesity loci in 1,395 women with diabetes from the Nurses' Health Study: 449 women developed CVD, and 946 women did not develop CVD. A genetic risk score (GRS) was derived by summing risk alleles for each individual. Four polymorphisms (rs9939609 [FTO], rs11084753 [KCTD15], rs10838738 [MTCH2], and rs10938397 [GNPDA2]) showed nominally significant associations with CVD. The GRS combining all obesity loci was linearly related to CVD risk (P = 0.013 for trend). The odds ratio was 1.08 per risk allele (95% confidence interval, 1.02-1.15; P = 0.01) after adjustment for body mass index and other conventional risk factors. Women with the highest quartile of GRS had 53% (95% confidence interval, 6%-122%) increased CVD risk, compared with those in the lowest quartile of GRS (P = 0.024). In addition, a higher GRS was associated with lower adiponectin levels (P = 0.02). Further adjustment for body mass index and other covariates did not change the association (P = 0.006). A higher GRS was also correlated with lower levels of high-density lipoprotein (P = 0.01).
Conclusions: Obesity-predisposing variants may jointly affect CVD risk among women with diabetes.