Effect of Polypharmacy on Long-Term Mortality After Percutaneous Coronary Intervention

Polypharmacy was reported to be associated with increased mortality in various populations. However, there is a scarcity of data on status of polypharmacy and association with long-term mortality in patients who underwent percutaneous coronary intervention (PCI). Among 12,291 patients who underwent first PCI in the CREDO-Kyoto PCI/CABG registry Cohort-3, we evaluated the number of medications at discharge from index PCI hospitalization, and compared long-term mortality across the 3 groups divided by the tertiles of the number of medications. The median number of medications was 6 (interquartile range: 5 to 8), and 88.0% of the patients were on >=5 medications. Most of medications were those related to cardiovascular disease. Patients taking more medications were older and more often had co-morbidities and guideline-indicated medications. The cumulative 5-year incidence of all-cause death increased incrementally with increasing number of medications (Tertile 1 [<=5]: 13.1%, Tertile 2 [6 to 7]: 13.9%, and Tertile 3 [>=8]: 18.0%, log-rank p <0.001). After adjusting confounders, the mortality risks of Tertile 2 and Tertile 3 relative to Tertile 1 were no longer significant (Tertile 2: hazard ratio 0.93; 95% confidence interval 0.84 to 1.04; p = 0.23, and Tertile 3: hazard ratio 0.91; 95% confidence interval 0.81 to 1.03; p = 0.14, respectively). In conclusion, in a real-world population of patients who underwent PCI, approximately 90% of patients were on >=5 medications. Increasing medications was associated with higher crude incidence of all-cause death, whereas adjusted mortality risks were similar regardless of the number of medications. These data might suggest that achievement of optimal medical therapy would be preferred, even if it might increase the number of medications used.