Frequency and Timing of Depression and Anxiety Diagnoses Following Cancer Diagnosis: A Multi-Center Cohort Study.

BACKGROUND: Depression and anxiety are common among individuals with cancer and are associated with adverse outcomes; however, the frequency, timing, and disparities of anxiety and depression diagnoses following cancer diagnosis remain incompletely characterized. METHODS: We conducted a retrospective, multi-center cohort study of 1,161,370 adults diagnosed with one of 10 common cancers between 2015 and 2025 within the University of California Health system using electronic health record data. Patients with depression or anxiety diagnoses in the year prior to cancer diagnosis were excluded. Incident anxiety and depression diagnoses were identified following cancer diagnosis. Fine-Gray competing risk regression models were used to examine factors associated with psychiatric diagnosis while accounting for death as a competing event. RESULTS: Overall, 22.2% of patients received a new anxiety or depression diagnosis after cancer diagnosis, including anxiety only (8.4%), depression only (5.7%), and comorbid depression and anxiety (8.2%). Although many diagnoses occurred within the first year, a substantial proportion were identified later. Female patients had higher hazards of depression, anxiety, and comorbid diagnoses compared with males. Asian patients had lower hazards across outcomes, while Hispanic or Latino patients and Medicaid-insured patients had higher hazards compared with reference groups. Timing varied by cancer type, with pancreatic cancer associated with the shortest time to diagnosis and prostate cancer with the longest. CONCLUSIONS: Incident depression and anxiety affect more than one in five patients following cancer diagnosis, with marked disparities by sociodemographic factors and cancer type. Delayed diagnoses highlight the need for longitudinal and equitable mental health screening throughout the cancer care continuum.