Advances in cancer therapies have led to an improved survival after childhood cancer, but also to numerous late adverse sequelae. We aimed to analyze late cardiovascular effects, the leading non-malignant complications, and mortality after cancer at a young age. 

Via linkage to the hospital discharge registry, we compared cardiovascular complications among 5-year survivors (13,860) younger than 35 years at cancer diagnosis to those of a healthy sibling cohort. Furthermore, the causes of death and purchases of cardiovascular medications and drugs associated with metabolic syndrome were evaluated after early onset cancer and compared to siblings and the general population by accessing the causes-of-death and the drug purchase registers. 

Both childhood and young adult cancer survivors were more prone to suffer from all studied cardiovascular conditions than their siblings with the highest hazard ratios (HRs) for cardiomyopathy/ cardiac insufficiency. Standardized mortality ratios (SMRs) were elevated after early onset cancer with respect to overall causes of death, cardiovascular causes, and other causes. Additionally, early onset cancer patients were more likely to purchase drugs for cardiovascular disorders and conditions associated with the metabolic syndrome than siblings. All studied cardiovascular outcomes were highly dependent on the cancer diagnosis and the age at cancer diagnosis. 

These studies emphasize the need for setting up long-term cardiovascular follow-up guidelines for early onset cancer survivors, especially in young adult cancer survivors who are still at lack of those. The prevention and early detection of cardiovascular late effects is the ultimate goal for their lifelong medical surveillance to ensure them a best possible quality of life.