FTO gene variant and risk of hypertension: A meta-analysis of 57,464 hypertensive cases and 41,256 controls

Abstract

Objectives Recent studies have suggested that fat mass and obesity-associated gene (FTO) may predispose individuals to develop hypertension. However, the results have been inconsistent. We performed a meta-analysis to investigate the relationship of FTO gene variant with risk of hypertension and influence of body mass index (BMI) on this risk. Materials/methods A systematic literature search in PubMed, Embase and ISI web of science databases was performed to identify eligible published literatures. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Results A total of seven studies comprising 57,464 hypertensive cases and 41,256 controls met the inclusion criteria and were included in the meta-analysis. The FTO gene variant(s) showed significant association with the risk of hypertension (OR = 1.16, 95% CI = 1.07–1.25, P < 0.001) which disappeared on adjustment for BMI (OR = 1.04, 95% CI = 0.98–1.10, P = 0.162). In addition, stratified analysis demonstrated a significant association of the FTO variant with the risk of hypertension in obese subjects (OR = 1.10, 95% CI = 1.01–1.19, P = 0.032) but not in non-obese individuals (OR = 1.00, 95% CI = 0.97–1.03, P = 0.832). Subgroup analysis based on ethnicity showed significant association between FTO variant and hypertension in both European (OR = 1.07, 95% CI = 1.01–1.14, P = 0.028) and Asian populations (OR = 1.37, 95% CI = 1.23–1.53, P <0.001). However, the association remained significant only in Asians (OR = 1.17, 95% CI = 1.01–1.35, P = 0.035) but not in the Europeans (OR = 1.02, 95% CI = 0.97–1.07, P = 0.390) on adjustment for BMI. Conclusions The present meta-analysis confirms that FTO genotype mediates obesity-related hypertension.