Heart Disease Mortality in Cancer Survivors: A Population‐Based Study in Japan

Abstract

Background Data on the risk of cardiovascular‐related mortality in patients with cancer are limited. Methods and Results This retrospective cohort study used data from the Osaka Cancer Registry and vital statistics in Japan between 1985 and 2013. The causes of death were investigated, and the risk of fatal heart disease was analyzed. Standardized mortality ratios were calculated to compare the risk of fatal heart disease between patients with cancer and the general population. Fine and Gray competing risk regression models were used to assess the risk of fatal heart disease among patients with cancer. In total, 682 886 patients with cancer were included in the analysis, and 335 635 patients died during the study period. Heart disease was the leading cause of noncancer deaths, with 10 686 deaths. Among the patients who died of heart disease, 5017 had ischemic heart disease, 3598 had heart failure, 356 had hypertensive disease, and 1715 had other heart diseases. The standardized mortality ratio for heart disease was 2.80 (95% CI, 2.74–2.85). The standardized mortality ratio for ischemic heart disease, heart failure, and hypertensive disease were 3.26 (95% CI, 3.17–3.35), 2.69 (95% CI, 2.60–2.78), and 5.97 (95% CI, 5.38–6.63), respectively. The risk of fatal heart disease increased over time after cancer diagnosis. Men were more likely to die of heart disease than women (subdistribution hazard ratio, 1.08 [95% CI, 1.02–1.16]). The risk of fatal heart disease among cancer survivors has decreased in recent years. Conclusions Cancer survivors have a higher risk of fatal heart disease than the general population.