Statin initiation and all-cause mortality in incident statin-naive dialysis patients

Background and aims: Cardiovascular disease is the main cause of death in end-stage kidney disease (ESKD) patients. We aimed to explore the association between statin initiation after starting dialysis and all-cause mortality in statin-naive ESKD patients. Methods: We analyzed nationwide claims data of incident dialysis patients from 2010 to 2017 in South Korea. Patients who had previous cardiovascular events or were administered statins before dialysis were excluded. The study group included dialysis patients receiving statins within 1 year after dialysis initiation. The control group was organized after propensity-score matching with age, sex, time of dialysis initiation, and underlying diabetes mellitus and hypertension. The main outcomes were all-cause mortality and major cardiovascular events. Results: We included 1596 patients who started statin treatment and 1:1 matched statin-nonusers. During the 9438 person-year follow-up, 468 deaths and 264 major adverse cardiovascular events (MACEs) occurred. Statin initiation was associated with a reduced risk of all-cause mortality (adjusted hazard ratio (aHR) 0.72, 95% confidence interval (CI) 0.60-0.87, p = 0.001), but not with MACE incidence (aHR 1.06, 95% CI 0.83-1.36, p = 0.62). In particular, patients prescribed the recommended dosage of statins according to the Kidney Disease Improving Global Outcomes guidelines showed the lowest mortality risk (aHR 0.55, 95% CI 0.40-0.75, p < 0.001). Conclusions: Statin initiation was associated with lower risk of all-cause mortality in statin-naive ESKD patients. As indication bias may be present in observational study setting, further prospective studies are warranted to validate the association of statin initiation with mortality in incident dialysis cases.