ABSTRACT
WHAT IS KNOWN AND OBJECTIVE: Breast cancer (BCa) and prostate cancer (PCa), both hormone-dependent cancers, are the second leading cause of death in both women and men, respectively. Calcium channel blockers (CCBs) have been thought to increase the risk of cancer by inhibiting calcium signal-mediated apoptosis, but the evidence for this association remains inconclusive. We have reviewed pertinent literature and pooled data to establish a consensus on the relationship of CCB use and the incidence of these two cancers. METHODS: PubMed was used to conduct a search for English articles from inception to April 2016. Relevant data including study design, number of total participants and CCB users, total cases of BCa and PCa, age (mean and/or range), follow-up period and statistical outcomes were retrieved. Quality assessment was carried out using Newcastle Ottawa system, with the selection of high-quality studies. Summary effects were obtained using random- and mixed-effects models, followed by sensitivity analysis, and testing for publication bias. RESULTS AND DISCUSSION: This meta-analysis includes 11 relevant studies for BCa and 6 for PCa. The odds ratio (OR) association between BCa and CCB use was 1.14 (95%CI: 1.02, 1.27, P = .02). The OR association between PCa and CCB use was 1.12 (95%CI .94-1.35, P = .21). WHAT IS NEW AND CONCLUSION: Although a statistically significant association between CCB use and incidence of BCa does exist, the limitations of the individual studies restrict the clinical application of this relationship. Our meta-regression model does newly identify a 9-year latency period of CCB use and a significantly increased risk of BCa. No significant association exists between CCB use and the incidence of PCa. Our meta-regression shows CCB may have a protective effect upon PCa incidence among older populations.
