Trends in optimal medical therapy at discharge and clinical outcomes in patients with acute coronary syndrome in Thailand.

BACKGROUND

Optimal medical therapy (OMT) is recommended for patients with acute coronary syndrome (ACS) at discharge. This study aimed to assess temporal trends of OMT prescription as a five-drug regimen at discharge and its association with clinical outcomes in patients with ACS in Thailand.

METHODS

A retrospective cohort study was conducted in a tertiary-care medical center in Thailand. Data were collected from an electronic medical database. Patients were categorized into OMT or non-OMT groups based on their discharge medications. OMT was defined as a combination of aspirin and P2Y12 inhibitors, statins, beta-blockers, and angiotensin-converting enzyme inhibitors, or angiotensin receptor blockers. The primary outcome was 1-year all-cause mortality. The secondary outcome was major adverse cardiac events (MACE) which was defined as a composite of non-fatal myocardial infarction, non-fatal stroke, and all-cause mortality. The prescription trends were also estimated. A multivariate Cox's proportional hazard model was used to assess the association of OMT prescriptions at discharge with all-cause mortality and MACE.

RESULTS

A total of 3531 patients discharged with ACS [mean age, 69.5 (SD 12.4) years; 58.3% male] were identified. Only 42.6% were discharged with OMT. The rates of OMT prescriptions did not change over time. However, the prescription of OMT with high-intensity statin was significantly increased from 5.0% in 2013 to 38.3% in 2018 (p for trend <0.001). Multivariable analyses indicated that OMT significantly reduced all-cause mortality (adjusted HR: 0.77; 95%CI: 0.63-0.95; p=0.012) and MACE (adjusted HR 0.84; 95%CI: 0.71-0.99; p = 0.044). Subgroup analysis indicated that patients receiving OMT with high-intensity statins exhibited survival benefits (adjusted HR: 0.72; 95%CI: 0.56-0.92; p=0.008).

CONCLUSIONS

The five-drugs comprising OMT were associated with a reduction in all-cause mortality and MACE in patients with ACS. Nevertheless, OMT prescribing remains underused and could be enhanced in the real-world setting.