Inequalities in long-term cardiovascular and metabolic outcomes in childhood and young adult cancer survivors

This thesis investigated inequalities in long-term cardiovascular, metabolic, and survival outcomes among children and young adults diagnosed with cancer in Yorkshire, United Kingdom. Survivors of childhood and young adult cancer (CYACS) are at elevated risk of developing modifiable cardiovascular risk factors such as diabetes, hypertension, and dyslipidaemia which increase their likelihood of severe or fatal cardiac events, making them a key population for targeted clinical intervention. However, key questions remain about the optimal timing, duration, and goals of such interventions.

To address this, population-based cancer registration data were linked with national and regional longitudinal electronic healthcare records to ascertain clinically validated outcome data. A combination of parametric and non-parametric time-to-event methods and regression standardisation techniques were used to estimate rates and risks of outcomes of interest over time and across patient and treatment characteristics.

Findings from this thesis revealed a general long-term trend of reducing ethnic and socio-economic inequalities in childhood cancer survival, contributing to overall improvements in survival rates in Yorkshire and a growing population of long-term survivors. Subsequent analysis identified a heightened risk of diabetes amongst these survivors, particularly following exposure to total body irradiation, abdominal radiotherapy, corticosteroids, and haematopoietic stem cell transplantation. The thesis also identified a substantial burden of dyslipidaemia and other metabolic conditions among CYACS, with distinct patterns in how these conditions were temporally associated with long-term cardiovascular morbidity. These findings highlight the importance of equitable healthcare access and persistent risk-stratified monitoring, as well as the need for further research into targeted interventions to improve long-term cardiovascular and metabolic health outcomes for CYACS.