Association between constipation and risk of coronary heart disease: a systematic review and meta-analysis of cohort studies

Objective This systematic review and meta-analysis aimed to evaluate the association between constipation and risk of coronary heart disease (CHD). Methods We systematically searched PubMed, Web of Science, and Cochrane Library until 28 February 2025. Published cohort studies reporting quantitative association measures for CHD in constipated vs. non-constipated individuals were included. The heterogeneity was assessed via the chi-square test based on Cochrane Q statistics. I 2 > 50% or Q -test p < 0.05 indicated substantial heterogeneity, warranting random-effects modeling; otherwise, fixed-effects models were implemented. Subgroup evaluations were conducted for study design type, region, category of CHD, follow-up duration, and gender. Results Nine studies involving 283,070 constipation cases and 3,343,120 controls were analyzed. Constipation was associated with a 10% increased CHD risk [hazard ratio (HR] = ).10, 95% confidence interval (CI): 1.05–1.15]. Statistical heterogeneity ( I 2 = 42.5%, p = 0.03) was observed in the present study. Subgroup analyses revealed a stronger association with myocardial infarction (HR = 1.14, 95% CI: 1.05–1.23). Notably, constipation showed no CHD risk elevation in women (HR = 1.04, 95% CI: 0.98–1.11), with reduced residual heterogeneity ( I 2 = 30.2%, p = 0.177). Conclusion Our meta-analysis identified a significant positive association between constipation and CHD risk, particularly myocardial infarction. These findings suggest that constipation may either accelerate the pathological processes underlying CHD or that both conditions share common etiological pathways, warranting further mechanistic and interventional studies.