Case-control reports published in English were searched totaling four studies with six populations (823 cases and 916 controls). Random-effects model was applied irrespective of between-study heterogeneity, and study quality was assessed in duplicate.
Compared with − 58C allele carriers, those with − 58T allele had a lower yet nonsignificant risk for hypertension (OR = 0.86; 95 % CI: 0.68–1.09; P = 0.21). Lack of significance persisted after combining those with genotypes − 58TC and − 58TT together (OR = 0.87; 95 % CI: 0.67–1.09; P = 0.21) or with − 58TC and − 58CC together (OR = 0.75; 95 % CI: 0.48–1.18; P = 0.22) in association with hypertension. Sensitivity analyses by race indicated that comparison of − 58T versus − 58C generated a protective effect for hypertension in Asians (OR = 0.77; 95 % CI: 0.58–1.02; P = 0.07) and African-Americans (OR = 0.65; 95 % CI: 0.43–0.98; P = 0.04), but a risk effect in Caucasians (OR = 1.22; 95 % CI: 0.92–1.61; P = 0.17). No publication bias was observed.
Our results suggested that − 58T allele exhibited a protective effect on hypertension in Asians and African-Americans, yet a risk effect in Caucasians.