Constipation and risk of death and cardiovascular events in patients on hemodialysis.

Background: Constipation is a common gastrointestinal disorder and is often accompanied by alteration in the gut microbiota. Recently, several studies have disclosed its association with an increased risk of cardiovascular disease and mortality in the general population. Despite the high prevalence of constipation, data on the clinical impact of constipation in patients with chronic kidney disease are limited. We aimed to explore the prevalence of constipation and its association with cardiovascular disease in chronic kidney disease using a nationally representative cohort of hemodialysis patients.

Methods: This study used hemodialysis quality assessment and health insurance claims data from patients undergoing maintenance hemodialysis in South Korea. Chronic constipation was defined using the total number of laxatives prescribed during the 1-year baseline period. The primary outcome was a composite of acute ischemic stroke, hemorrhagic stroke, myocardial infarction, or all-cause death. Secondary outcomes were the individual components of the primary outcome.

Results: Among 35,230 patients on hemodialysis, 9,133 (25.9%) were identified as having constipation. During a median follow-up of 5.4 years, patients with constipation had a 15% higher incidence of the composite outcome, 16% higher incidence of ischemic stroke, and 14% higher all-cause mortality, after multivariate adjustment.

Conclusion: Chronic constipation requiring laxatives was associated with a higher risk of the composite outcome of cardiovascular events or all-cause death in patients on hemodialysis. Further studies are needed to confirm whether constipation is an independent predictor or a possible causal factor of cardiovascular disease.