Intradialytic hypotension and cardiovascular and noncardiovascular mortality in hemodialysis patients: a retrospective cohort study

Abstract

Background: Intradialytic hypotension (IDH) has traditionally been associated with cardiovascular diseases (CVD). Recent demographic shifts in hemodialysis (HD) patients, including an aging population, have altered mortality patterns and led to a decline in CVD mortality. Considering these changes, we aimed to re-evaluate the prognostic impact of intradialytic hypotension in a contemporary aging HD cohort. Methods: This is a single-center retrospective cohort study, including 228 HD patients. In each patient, 12 consecutive HD records were examined to count numbers of IDH episodes. The patients were then divided into two groups: an IDH group for patients with at least one episode of IDH (n = 111) and a non-IDH group (n = 117) for those without an episode of IDH. We analyzed all-cause mortality and causes of death, including a comparison of CVD and non-CVD mortality between the two groups over a median follow-up period of 5.7 (2.3–7.8) years. Results: The age of the study population was 65.4 ± 12.7 years, and the median dialysis vintage was 7.2 (2.8–12.7) years. The IDH group experienced an average of 3.9 episodes of IDH during the 12 HD sessions. During the follow-up period, 91 patients (39.9%) died. Multivariate analysis identified IDH and ischemic heart disease as independent risk factors for all-cause mortality. All-cause mortality was higher in the IDH group than in the non-IDH group (51.4% versus 29.1%, p < 0.01). While CVD mortality was similar between the groups (16.2% versus 15.4%, p = 1.00), non-CVD mortality significantly increased in the IDH group (35.1% versus 13.7%, p < 0.01), predominantly owing to infections. Patients with IDH exhibited significantly lower serum albumin levels (3.4 versus 3.6 g/dL, p < 0.01) and higher C-reactive protein levels (median 0.2 versus 0.1 mg/dL, p = 0.04), which may reflect malnutrition and chronic inflammation. Conclusions: IDH is associated with an increased risk of all-cause mortality, particularly of non-CVD, including deaths from infection and malnutrition.