Suicide mortality among survivors of first primary thyroid cancer: a population-based competing risk analysis

Thyroid cancer is associated with favorable survival, yet suicide risk during long-term survivorship remains incompletely characterized, particularly in the presence of competing mortality.

We identified 178,014 patients with first primary thyroid cancer from the SEER 17 database between 2000 and 2022. Suicide mortality was quantified using standardized mortality ratios. Risk factors were evaluated using cause-specific Cox models and Fine-Gray competing risk regression, with non-suicide deaths treated as competing events.

During 1,566,507 person-years of follow-up, 165 suicides occurred, corresponding to 10.53 deaths per 100,000 person-years. Overall suicide mortality was comparable to that of the general population. In cause-specific Cox models, older age, no surgery, and chemotherapy appeared associated with suicide risk. These associations did not reach statistical significance in the Fine-Gray model. Male sex, single status, and separated/divorced status remained independently associated with higher suicide incidence, whereas the highest area-level median household income category was associated with lower suicide incidence.

Sociodemographic factors were associated with suicide incidence in the Fine-Gray model, supporting attention to psychosocial vulnerability alongside disease-related needs. These findings support incorporating social vulnerability assessment, psychosocial screening, and referral pathways into supportive care for patients with thyroid cancer.