A comparison of the risk of acute myocardial infarction in patients receiving hemodialysis and peritoneal dialysis: A population-based, propensity score-matched cohort study

Abstract

Background and aims: Acute myocardial infarction (AMI) remains the major cause of morbidity and mortality in the dialysis population. Traditional cardiovascular (CV) risk factors are unable to fully account for the high incidence of AMI in the dialysis population. In this study, we investigated whether dialysis modalities could be one of the uremia-specific risk factors for AMI.

Methods: Using the National Health Insurance Research Database, we recruited all incident dialysis patients from the period January 1, 1998 to December 31, 2010. The propensity score matching method was applied to form the matched pairs of hemodialysis (HD) and peritoneal dialysis (PD) patients. Incidence rate (IR), cumulative incidence rate (CIR) and multivariable subdistribution hazards models were employed to compare the risk of AMI in the HD and PD groups.

Results: Of the 86,215 incident dialysis patients, 5,513 matched pairs of HD and PD patients were identified. The HD patients had a higher IR of AMI than the PD patients (9.71 vs. 8.35 per 1000 patient-years, respectively, p = 0.01). The CIR was also higher in the HD patients than in the PD patients (0.09 vs. 0.05), especially 4 years after dialysis therapy was initiated (p = 0.04). In the subdistribution hazards models, HD was still significantly associated with a higher risk of developing AMI (adjusted hazard ratio:1.30, 95% confidence interval:1.02-1.65). The results remained unchanged in various stratifications as well as in the analysis of the unmatched cohorts.

Conclusions: Compared to PD, HD was significantly associated with higher risk of developing AMI, especially after 4 years since dialysis was initiated. Prevention and routine surveillance programs for AMI should be individualized according to dialysis modalities and vintage.

Keywords: Acute myocardial infarction; Competing risk analysis; Hemodialysis; Peritoneal dialysis; Propensity score.