Abstract
IMPORTANCE: Controversy exists regarding whether statin therapy has benefits for patients with kidney failure, and the consequences of statin therapy for patients with kidney failure and concomitant peripheral artery disease (PAD) are particularly uncertain. OBJECTIVE: To evaluate the association of statin therapy with cardiovascular (CV) and limb outcomes among patients with kidney failure and concomitant PAD and dyslipidemia who are receiving long-term maintenance dialysis. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study used data from the Taiwan National Health Insurance Research Database. A total of 20 731 patients with kidney failure receiving long-term maintenance dialysis who were diagnosed with PAD and dyslipidemia between January 1, 2001, and December 31, 2013, were identified, and 10 767 patients met study criteria. Data were analyzed from June 8, 2021, to June 2, 2022. MAIN OUTCOMES AND MEASURES: Primary outcomes were all-cause death and the composite of endovascular therapy (EVT) and amputation. Other outcomes of interest included CV events (CV death, acute myocardial infarction, ischemic stroke, and hospitalization for heart failure), major adverse limb events (new-onset claudication, new-onset critical limb ischemia, EVT, and nontraumatic amputation), and all-cause readmission. All outcomes were examined at 1 year and 3 years of follow-up. To minimize selection bias, propensity score matching on a 1:1 ratio was performed among patients receiving statin therapy (statin group) and patients not receiving statin therapy (nonstatin group). A defined daily dose (DDD) approach was used to evaluate whether the association of statin therapy with the risk of primary outcomes was dose dependent. RESULTS: Among 20 731 patients with kidney failure and concomitant PAD and dyslipidemia receiving long-term maintenance dialysis, 10 767 patients (5593 women [51.9%]; mean [SD] age, 68.5 [11.5] years; all of Taiwanese ethnicity) met the predetermined study criteria; of those, 3597 patients were receiving statin therapy, and 7170 were not. A total of 6470 patients (mean [SD] age, 66.4 [11.3] years; 3359 women [51.9%]) were included in the 1:1 propensity score-matched cohort, with 3235 patients in each group (statin and nonstatin). The incidence and risk of CV and all-cause death were significantly lower in the statin group vs the nonstatin group at 3 years of follow-up (CV death: 611 patients [18.9%] vs 685 patients [21.2%]; hazard ratio [HR], 0.86 [95% CI, 0.77-0.96]; P = .008; all-cause death: 1078 patients [33.3%] vs 1138 patients [35.2%]; HR, 0.92 [95% CI, 0.84-0.996]; P = .04). Statin use was also associated with a significantly lower incidence and risk of the composite adverse limb outcome of EVT and amputation at 3 years of follow-up (314 patients [9.7%] vs 361 patients [11.2%]; subdistribution HR, 0.85 [95% CI, 0.73-0.99]; P = .04). Results of subgroup analyses were consistent with those of the primary analysis across all subgroup variables. In the adjusted dose-response analysis, the risk reduction associated with statin use increased in a dose-dependent manner for both all-cause death (HR: 0.95 for DDD <0.50, 0.92 for DDD 0.50-0.99, 0.85 for DDD 1.00-1.49, and 0.79 for DDD ≥1.50; P = .002 for trend) and the composite outcome of EVT and amputation (subdistribution HR: 0.79 for DDD <0.50, 0.78 for DDD 0.50-0.99, 0.82 for DDD 1.00-1.49, and 0.58 for DDD ≥1.50; P = .002 for trend) compared with no statin therapy; however, not all findings in the DDD analysis were statistically significant. CONCLUSIONS AND RELEVANCE: In this cohort study, statin therapy was associated with reductions in the risk of all-cause death, CV death, and the composite adverse limb outcome of EVT and amputation. These findings suggest that statin therapy may have protective CV and limb benefits for patients with kidney failure and concomitant PAD who are receiving long-term maintenance dialysis.