Non-ST-Segment Elevation Myocardial Infarction (NSTEMI) in a High-Risk Rheumatoid Arthritis Patient on Long-Term Baricitinib: Drug Signal or Risk Factor Convergence?

Rheumatoid arthritis (RA) is associated with increased cardiovascular (CV) morbidity and mortality, partly related to chronic systemic inflammation and accelerated atherosclerosis. Janus kinase (JAK) inhibitors, including baricitinib, are effective targeted therapies for RA, but their use in older patients and those with baseline CV risk factors requires careful risk assessment. We report a clinically detailed case of non-ST-elevation myocardial infarction (NSTEMI) during long-term baricitinib therapy and use it to discuss real-world CV risk stratification, monitoring, and pharmacovigilance in patients with RA receiving JAK inhibitors. A 77-year-old Omani woman with seropositive erosive RA since age 69 (Month 0), poorly controlled type 2 diabetes mellitus, well-controlled hypertension, well-controlled hyperlipidemia, obesity, and family history of myocardial infarction was treated with baricitinib 4 mg daily (Month 47) after inadequate response to previous disease-modifying antirheumatic drugs. Her RA remained in sustained remission for approximately 33 months on baricitinib and methotrexate. A cardiac evaluation performed five years earlier, including echocardiography and dobutamine stress testing, had not shown evidence of inducible ischemia or structural heart disease at that time. She subsequently developed sudden chest pain during physiotherapy, was diagnosed with NSTEMI (Month 79), and underwent percutaneous coronary intervention for severe calcified coronary artery disease with critical left anterior descending and diagonal branch stenoses. Baricitinib was discontinued at Month 80, and she remained in RA remission on methotrexate alone without recurrent CV events through her most recent follow-up (Month 108). A comprehensive literature review using MEDLINE/PubMed, Scopus, EMBASE, and Google Scholar identified only three relevant cases describing NSTEMI during baricitinib therapy in RA, but they lacked sufficient clinical detail for meaningful comparison. Naranjo adverse drug reaction probability scale supports a possible association. This case highlights the need for structured CV risk reassessment, shared decision-making, and pharmacovigilance during long-term JAK inhibitor therapy in high-risk patients with RA.