Depression and use of health care services in patients with advanced cancer.

OBJECTIVE To examine whether depression in patients with advanced cancer is associated with increased rates of physician visits, especially to primary care. DESIGN Retrospective, observational study linking depression survey data to provincial health administration data. SETTING Toronto, Ont. PARTICIPANTS A total of 737 patients with advanced cancer attending Princess Margaret Hospital, who participated in the Will to Live Study from 2002 to 2008. MAIN OUTCOME MEASURES Frequency of visits to primary care, oncology, surgery, and psychiatry services, before and after the depression assessment. RESULTS Before the assessment, depression was associated with an almost 25% increase in the rate of primary care visits for reasons not related to mental health (rate ratio [RR] = 1.23, 95% CI 1.00 to 1.50), adjusting for medical morbidity and other factors. After assessment, depression was associated with a 2-fold increase in the rate of primary care visits for mental health-related reasons (RR = 2.35, 95% CI 1.18 to 4.66). However, depression was also associated during this time with an almost 25% reduction in the rate of oncology visits (RR = 0.78, 95% CI 0.65 to 0.94). CONCLUSION Depression affects health care service use in patients with advanced cancer. Individuals with depression were more likely to see primary care physicians but less likely to see oncologists, compared with individuals without depression. However, the frequent association of disease-related factors with depression in patients with advanced cancer highlights the need for communication between oncologists and primary care physicians about the medical and psychosocial care of these patients.