A large-scale study of adults diagnosed with cancer has found that those who develop a mental health disorder within the first year after diagnosis face a significantly higher risk of death in subsequent years.
The research was published online in CANCER, a peer-reviewed journal of the American Cancer Society, examined data from 371,189 adult patients diagnosed between 2013 and 2023 at University of California-affiliated hospitals. The analysis focused on patients with no documented mental health disorder prior to their cancer diagnosis.
Of those included, 39,687 patients, or 10.6%, were diagnosed with a mental health disorder within a year of learning they had cancer.
After adjusting for demographics, cancer type, stage, treatment and comorbidities, researchers found that a new mental health diagnosis was linked to a 51% higher risk of death during the first 1–3 years following cancer diagnosis. The increased risk declined to 17% in years 3–5 and was no longer observed in later periods.
Lead author Julian Hong, MD, MS, of the University of California, San Francisco, said the findings reinforce previous evidence.
“Over the past several years, we’ve had an increasing appreciation for the important relationship between cancer, its treatment, and mental health,” Hong said. “This study reproduces our prior work by leveraging the shared experience across the University of California system, reinforcing a relationship between mental health conditions and mortality for patients with cancer and highlighting the need to prioritise and manage mental health.”
The researchers note that depression, anxiety, and adjustment disorders are common following a cancer diagnosis. Emotional distress, treatment side effects, and uncertainty about prognosis can contribute to psychological difficulties. Reduced treatment adherence, poorer self-care, biological changes such as inflammation, and delayed detection of complications may help explain the higher mortality risk.
Earlier analyses by some of the same investigators had identified similar short-term associations. The current study expands on that work with a decade of data and a substantially larger cohort.
Although the study was observational and does not establish causation, its scale and statistical adjustments strengthen the evidence linking newly diagnosed mental health conditions to survival outcomes.
The findings support recommendations for routine distress screening in oncology settings. Guidelines from organisations such as the American Cancer Society and the National Comprehensive Cancer Network call for integrating psychosocial support into standard cancer care. Interventions may include psychological therapy, counselling, medication, and multidisciplinary support, particularly during the critical early years after diagnosis.