Background: Opium consumption has been an overlooked health issue in the Iranian population, and the prognostic role of opium consumption in patients undergoing coronary revascularization is unknown. Hypothesis: We aimed to assess the association between opium consumption and long-term cardiovascular outcomes after percutaneous coronary intervention (PCI). Methods: We screened 2203 consecutive patients who underwent elective PCI between April 2009 and April 2010 at Tehran Heart Center. Exclusion criteria were unsuccessful PCI, non-elective PCI, and missing opium use data. Opium consumption was defined as self-reported ever use of any traditional opium substances. Outcomes of interest were all-cause mortality and a composite of major adverse cardiac and cerebrovascular events (MACCE). The association between opium use and study outcomes was evaluated using the inverse probability of treatment weighting (IPTW) method. Cumulative hazard curves were demonstrated to further assess the association visually. Furthermore, the effect of opium consumption on individual components of MACCE was evaluated in a competing risk setting. Results: A total of 2025 elective PCI patients were included (age: 58.7 ± 10.67, 29.1% women), among whom 297 (14.6%) patients were opium users. After a median follow-up of 10.7 years, opium consumption was associated with a higher risk of all-cause mortality (IPTW-hazard ratio [HR] = 1.705, 95% CI: 1.125–2.585; P = 0.012) and MACCE (IPTW-HR = 1.578, 95% CI: 1.156–2.153; P = 0.004). The assessment of MACCE components suggested a non-significant borderline trend for higher non-fatal myocardial infarction (IPTW–sub-distribution HR [SHR] = 1.731, 95% CI: 0.928–3.231; P = 0.084) and mortality (IPTW-SHR = 1.441, 95% CI: 0.884–2.351; P = 0.143) among opium users. Conclusions: Opium consumption is associated with a more than 50% increase in long-term risk of mortality and MACCE in patients undergoing PCI. These findings accentuate the importance of preventive strategies to quit opium addiction in this population.
