Nephrolithiasis and risk of hypertension: a meta-analysis of observational studies

Background: Observational studies have demonstrated an association between nephrolithiasis and hypertension. The aim of this meta-analysis was to summarize all available evidence. Methods: PubMed, EMBASE, the Cochrane Central Register of Controlled Trials databases, and the reference lists of relevant articles were searched to identify observational studies that reported study-specific risk estimates comparing the risk of hypertension in patients with nephrolithiasis. We used a random-effect model to pool the study-specific risk estimates. We also assessed the potential heterogeneity by subgroup analyses, meta-regression analyses, and sensitivity analyses. Results: A total of 7 articles including 9 studies (n = 313,222 participants) were eventually identified in this meta-analysis. In comparison with the patients who did not have nephrolithiasis, nephrolithiasis significantly increased the risk of hypertension (OR, 1.43; 95% CI, 1.30-1.56), with significant heterogeneity between these studies (I-2 = 83.5%, P < 0.001). The heterogeneity reduced in subgroups of cohort studies, USA, large sample size trials, men, and adjustment for confounding factors >= 5. Sensitivity analysis further demonstrated the results to be robust. Conclusions: Nephrolithiasis is associated with increased risk of hypertension. Future randomized, high-quality clinical trials are encouraged to definitively clarify the relationship between nephrolithiasis and hypertension, which may influence clinical management and primary prevention of hypertension in nephrolithiasis patients.