Cancer patients are at higher risk of developing and dying from cardiovascular disease than the general population, largely due to exposure to cardiotoxic cancer treatments and higher prevalence of risk factors common to both cancer and cardiovascular disease. There is limited Australian data on the incidence of cardiovascular disease after cancer. Internationally, most studies on cardiotoxicity have focused on breast cancer. As lung cancer survival rates improve, there is need to understand the issues facing this population.
For this analysis we analysed a subset of the CancerCostMod dataset, including all Queensland adults diagnosed with lung cancer during 2013-15. Everyone had two years of hospital admission data prior to cancer diagnosis to measure cardiovascular disease history (CV history) and three and half years follow-up data to measure new cardiovascular hospitalisation after cancer. The proportion of the cohort hospitalised during the follow-up period was calculated, and the excess risk of cardiovascular hospitalisation between groups was investigated by modelling time from cancer diagnosis to first cardiovascular hospitalisation, censoring for death and end of study, using Cox proportional hazard regressions.
4,369 Queenslanders diagnosed with lung cancer are included in this analysis. 12.4% had a history of cardiovascular hospitalisation, which was associated with older age and being male. 17.4% of the cohort had a hospitalisation for cardiovascular disease during follow-up. The proportion hospitalised for cardiovascular disease during follow-up increased with increasing age and decreasing residential remoteness and was higher in those with CV history than without (28.0% vs. 15.9%, p<0.01). Lung cancer patients with a CV history had a 2.4 times increased risk of being hospitalisations for cardiovascular disease during follow-up, and this did not reduce when adjusting for age, sex, Indigenous status, residential remoteness and residential socioeconomic advantage.
Recent hospitalisation for cardiovascular disease is a strong predictor of cardiovascular hospitalisation after lung cancer diagnosis.