Mental Health Service Contact Following Cancer Diagnosis and Associations with Cancer Mortality: Results from a Linked Population-Based Study of Adolescents and Young Adults in New South Wales.

Purpose: To assess the mental health conditions, as indicated by mental health service contact in adolescents and young adults (AYAs) diagnosed with cancer in New South Wales (NSW) and associations with cancer mortality. Methods: In 3998 NSW AYAs diagnosed with cancer in 2005-2017, mental health service contacts were obtained from hospital inpatient records and specified medical and pharmaceutical insurance claims. Odds of postcancer mental health contact were assessed by precancer mental contacts using logistic regression adjusted for sociodemographic and cancer characteristics. The risk of cancer-specific mortality related to postcancer mental health contacts was estimated using competing risk regression. Results: The prevalence of mental health service contacts in the 5 years postcancer diagnosis was 27.0%, higher than the corresponding precancer prevalence of 21.4%. The most common mental health conditions were depression and anxiety. The odds of having a mental health contact postcancer diagnosis were higher in patients with a precancer mental health service contact (adjusted odds ratio 5.69, confidence intervals [95% CIs]: 4.90-6.75). The 5-year cancer-specific survival was 87.9% (95% CI: 85.8-89.8) for patients with a mental health service contact postcancer, which was lower than the 93.9% (95% CI: 93.0-94.7) for patients without this contact. The subhazard ratio (SHR) for cancer mortality in patients having mental health service contact postcancer diagnosis was 1.67 (95% CI: 1.29-2.15), adjusted for sociodemographic characteristics, cancer stage, and precancer mental health status. Conclusion: The prevalence of mental health service contact increased after a cancer diagnosis. Mental health care should be a continued priority for AYA cancer patients, particularly for high-risk groups.