Depression symptom trends and health domains among lung cancer patients in the CanCORS study

Objectives: Among lung cancer patients depression symptoms are common and impact outcomes. The aims of this study were to determine risk factors that contribute to persistent or new onset depression symptoms during lung cancer treatment, and examine interactions between depression symptoms and health domains that influence mortality.

Materials and methods: Prospective observational study in five healthcare systems and 15 Veterans Affairs medical centers. Patients in the Cancer Care Outcomes Research and Surveillance (CanCORS) Consortium with lung cancer were eligible. The 8-item Center for Epidemiologic Studies Depression (CES-D) scale was administered at baseline and follow-up. Scores ≥4 indicated elevated depressive symptoms. Health domains were measured using validated instruments. We applied logistic regression and Cox proportional hazards modeling to explore the association between depression symptoms, health domains, and mortality.

Results: Of 1790 participants, 38% had depression symptoms at baseline and among those still alive, 31% at follow-up. Risk factors for depression symptoms at follow-up included younger age (OR=2.81), female sex (OR=1.59), low income (OR=1.45), not being married (OR=1.74) and current smoking status (OR=1.80); high school education was associated with reduced odds of depression symptoms at follow-up, compared with lesser educational attainment (OR=0.74) (all p values <0.05). Patients with depression symptoms had worse health-related quality of life, vitality, cancer-specific symptoms, and social support than patients without depression symptoms (all p<0.001). The association between depression symptoms and increased mortality is greater among patients with more lung cancer symptoms (p=0.008) or less social support (p=0.04).

Conclusions: Patient risk factors for depression symptoms at follow-up were identified and these subgroups should be targeted for enhanced surveillance. Patients with depression symptoms suffer across all health domains; however, only more lung cancer symptoms or less social support are associated with worse mortality among these patients. These potentially modifiable health domains suggest targets for possible intervention in future studies.