The effect of depression on stage at diagnosis, treatment, and survival in pancreatic adenocarcinoma.

Abstract

Depression has been associated with delayed presentation, inadequate treatment, and poor survival in patients with cancer. Using Surveillance, Epidemiology and End Results and Medicare linked data (1992-2005), we identified patients with pancreatic adenocarcinoma (N = 23,745). International classification of diseases, 9th edition, clinical modification codes were used to evaluate depression during the 3 to 27 months before the diagnosis of cancer. The effect of depression on receipt of therapy and survival was evaluated in univariate and multivariate models. Of patients with pancreatic cancer in our study, 7.9% had a diagnosis of depression (N = 1,868). Depression was associated with increased age, female sex, white race, single or widowed status, and advanced stage disease (P < .0001). In an adjusted model, patients with locoregional disease and depression had 37% lower odds of undergoing surgical resection (odds ratio, 0.63; 95% confidence interval, 0.52-0.76). In patients with locoregional disease, depression was associated with lower 2-year survival (hazard ratio, 1.20; 95% confidence interval, 1.09-1.32). After adjusting for surgical resection, this association was attenuated (hazard ratio, 1.14; 95% confidence interval, 1.04-1.26). In patients who underwent surgical resection, depression was a significant predictor of survival (hazard ratio, 1.34; 95% confidence interval, 1.04-1.73). Patients with distant disease and depression had 21% lower odds of receiving chemotherapy (odds ratio, 0.79; 95% confidence interval, 0.70-0.90). After adjusting for chemotherapy for distant disease, depression was no longer a significant predictor of survival (hazard ratio, 1.03; 95% confidence interval, 0.97-1.09). The decreased survival associated with depression appears to be mediated by a lower likelihood of appropriate treatment in depressed patients. Accurate recognition and treatment of pancreatic cancer patients with depression may improve treatment rates and survival.