Age-dependent risk of hematologic malignancies after acute myocardial infarction: a nationwide cohort study

Survivors of acute myocardial infarction (AMI) may be at increased risk of malignancy; however, whether this association differs by age remains unclear. Using the Korean National Health Insurance Service database, we assembled a nationwide retrospective cohort of adults with incident AMI (January 1, 2003–December 31, 2016) and 1:2 propensity-score–matched non-AMI controls based on age and sex. Participants were followed from the index date to incident hematologic malignancy, death (competing risk), or December 31, 2021. Risks were estimated using Fine–Gray competing-risk regression with multivariable adjustment for demographics and comorbidities. Age- and sex-standardized incidence ratios (SIRs) were calculated using national cancer incidence rates. The cohort included 294,398 AMI patients and 558,084 controls. Hematologic malignancies occurred in 2,886 AMI patients and 7,297 controls, with crude incidence rates of 1.23 and 0.91 per 1,000 person-years, respectively. AMI was associated with an increased risk of hematologic malignancy (adjusted HR 1.42, 95% CI 1.34–1.52). The association was strongest in patients aged < 50 years (HR 2.01, 95% CI 1.62–2.51) and remained significant across older groups, with progressively higher relative risks at younger ages. In SIR analyses, incidence was higher than expected, particularly for myeloproliferative neoplasms (SIR 4.83) and multiple myeloma (SIR 3.34), with higher SIRs in younger age strata. AMI was associated with an increased risk of hematologic malignancy, with a disproportionately higher risk in patients < 50 years. These findings may inform long-term risk stratification and assessment of non-cardiovascular outcomes in younger AMI survivors. A schematic overview illustrating the association between acute myocardial infarction and an increased risk of hematologic malignancies, with a stronger relative association observed in younger patients