Prediagnosis cardiovascular risk and subsequent myocardial infarction (MI) among lymphoma survivors.

Abstract

7564 Background: Chest radiation is associated with increased risk of MI among lymphoma survivors. The extent to which pre-existing cardiovascular risk factors also contribute to risk is understudied. We investigated this association among a national population of lymphoma survivors with a full range of cardiovascular risk factors. Methods: Using Danish population-based registries, we identified all adults diagnosed with aggressive non-Hodgkin lymphoma or Hodgkin lymphoma from 2000-2010 and followed them from 1 year after diagnosis through 2016. MI was ascertained from the nationwide Hospital Discharge Register and Cause of Death Register. Cardiovascular risk factors (hypertension, dyslipidemia, and diabetes), vascular disease, and intrinsic heart disease prevalent at lymphoma diagnosis were ascertained algorithmically using the National Prescription Register and the Hospital Discharge Register. Controlling for age, sex, histology, receipt of chest radiation, and prevalent cardiovascular diseases, we used multivariable Cox regression to test the association between pre-existing cardiovascular risk factors and subsequent MI. Results: Among 4246 survivors of lymphoma, median age at diagnosis was 60 (interquartile range 45-70 years); median follow-up was 6.9 years (range 0-16 years). 115 survivors were diagnosed with MI. Before lymphoma diagnosis, 28% of survivors had ≥1 cardiovascular risk factor, and 16% of survivors received chest radiation. In multivariable analysis, survivors who received chest radiation had an increased risk of MI compared to survivors who did not (HR=1.92 [95% CI=1.16-3.17]). Survivors with ≥1 cardiovascular risk factor had an increased risk of MI compared to survivors with none (HR = 2.44 [95% CI=1.65-3.62]). Conclusions: In a large, well-characterized, nationally representative study of contemporarily treated lymphoma survivors, prevalent hypertension, dyslipidemia, and diabetes were associated with later MI. Findings suggest that pre-existing cardiovascular risk factors confer the same amount of MI risk as does chest radiation. To prevent MI among survivors, decisions about post-treatment monitoring should address prevalent cardiovascular risk.