Association of echocardiographic left ventricular structure with the ACE D/I polymorphism: a meta-analysis

Introduction: In a previous meta-analysis, we derived pooled estimates for the association of left ventricular mass (LVM) and hypertrophy (LVH), as diagnosed by electrocardiography or echocardiography, with the ACE D/I polymorphism. We updated this meta-analysis until May 2009 only considering echocardiographic phenotypes. Methods: We computed pooled estimates from a random-effects model. Results: Across 38 studies, both DD homozygotes (n = 2440) and DI heterozygotes (n = 4310) had higher (p <= 0.002) LVM or LVM index than II homozygotes (n = 2229). Across 21 studies with available data, this was due to increased mean wall thickness (MWT) with no difference in left ventricular internal diameter (LVID). Standardised differences (DD versus II) were 0.39 (p < 0.001) for LVM, 0.34 (p = 0.009) for MWT, and 0.066 (p = 0.26) for LVID. Across 16 studies (4894 participants), the pooled odds ratios of LVH (versus II homozygotes) were 1.11 (p = 0.29) and 1.02 (p = 0.88) for the DD and DI genotypes, respectively. Sensitivity analyses were confirmatory. Conclusions: Our meta-analysis supports the hypothesis that the enhanced ACE activity associated with the D allele is associated with higher LV mass. Smaller sample size might explain the lack of significant association with LVH.