Angiotensin-converting enzyme insertion/deletion polymorphism and susceptibility to Henoch–Schönlein purpura: a meta-analysis

Objective: Meta-analysis was performed in the current study to evaluate the relationship of the angiotensin-converting enzyme insertion/deletion polymorphism with the risk of the incidence of Henoch–Schönlein purpura. Methods: The electronic databases, including Embase, PubMed and Google scholar, were systemically retrieved to search for related articles. Meanwhile, statistical analysis was performed using the odds ratio and the corresponding 95% confidence interval. Results: A total of six articles enrolling 504 patients and 706 healthy controls was enrolled into the current meta-analysis. Results of the meta-analysis suggested that the angiotensin-converting enzyme D allele was markedly correlated with the risk of the incidence of Henoch–Schönlein purpura among the general population (deletion (D) vs. insertion (I): odds ratio (OR) 1.42, 95% confidence interval (CI) 1.05–1.93; DD vs. II: OR 2.23, 95% CI 1.06–4.70; DI vs. II: OR 1.36, 95% CI 1.00–1.85; dominant model: OR 1.56, 95% CI 1.00–2.42; recessive model: OR 1.83, 95% CI 1.06–3.16). Moreover, such a polymorphism was found to correlate with the susceptibility to Henoch–Schönlein purpura when studies were stratified according to the sample size of over 200. In addition, such a polymorphism was recognised to be remarkably associated with the susceptibility to Henoch–Schönlein purpura in the Caucasian population, which was not found in the Asian population. Conclusions: The results of the current meta-analysis indicate that the angiotensin-converting enzyme D allele might be a risk factor against the risk of Henoch–Schönlein purpura, especially in Caucasians.