Anxiety and depressive disorders among children and young people following a cancer diagnosis in England: a retrospective cohort study

Background: Children and young people (CYP) diagnosed with cancer increasingly survive into adulthood, and therefore psychiatric conditions are an important survivorship outcome. However, many population-based studies have examined hospital contacts only and did not account for death as a competing event, which can bias risk estimates. We estimated absolute and relative risks of first-time anxiety and related disorders and depressive disorders, and psychotropic medication use among CYP aged 0-24 years in England. Methods: We conducted a population-based matched cohort study using primary care records from the Clinical Practice Research Datalink (CPRD) Aurum dataset linked to Hospital Episode Statistics (HES) records. CYP diagnosed with malignant cancer or tumours of the central nervous system between Jan 1, 2000, and Dec 31, 2022, were matched by age, sex, and general practice to up to 20 comparator patients without a cancer diagnosis at the index date. Follow-up was from index date to practice deregistration, last data collection, or study end date. We estimated cumulative incidence functions and cause-specific hazard ratios (HRs) using stratified Cox models, with death accounted for as a competing risk. Findings: There were 9 145 CYP with cancer (45·7% female) and 183 908 comparators in the study cohort. Median follow-up to first outcome was 3·7 years (interquartile range 1·0-8·7) for CYP with cancer and 6·0 years (2·6-10·8) for comparators. Across the follow-up period, adjusted HRs for incident anxiety and related disorders were 1·74 (95% confidence interval: 1·61-1·88), 1·16 (1·06-1·26) for depressive disorders, 1·27 (1·20-1·35) for antidepressants use, 2·21 (2·05-2·38) for antipsychotics use, and 2·69 (2·53-2·86) for anxiolytics use. HRs for anxiety and depressive disorders were highest in the first two years after diagnosis, and up to five years post-diagnosis for psychotropic medications, particularly among younger patients. Interpretation: CYP diagnosed with cancer have a sustained excess risk of first-time anxiety and related disorders and psychotropic medication use, and a modest excess hazard of depressive disorders. For clinicians, this supports proactive mental health monitoring and timely referral pathways embedded within cancer and survivorship care, especially in the early post-diagnosis period.