Predictors of depression in patients diagnosed with cancer and their caregivers

Background: Patients diagnosed with cancer and their caregivers have an increased risk for depression compared to the general population. The aims of the present study were to determine the rate of depressive symptoms in the clinical range, identify predictors of depression, and to determine if depression was a predictor of immune system parameters in both patients and caregivers. Methods: A secondary analysis of baseline data from two clinical trials was used for the purposes of this study. Patients and caregivers completed a battery of questionnaires. Patients were assessed on sociodemographic factors, fatigue, perceived stress, and pain levels. Caregivers reported measures on sociodemographic factors, quality of life, and sleep quality. Descriptive statistics and logistic regression were performed to test the hypotheses. Results: Of the 259 patient and caregiver dyads that were included in the analyses, the mean age of patients was 64.7 (SD = 10.5), and the majority were Caucasian (92.9%) and female (56.6%). The mean age of caregivers was 58.5 (SD = 12.5), and the majority were Caucasian (93.2), female (73.7%), and the spouse of the cancer patient (63.5%). The rate of depressive symptoms in the clinical range in patients was 37.4% and 36.7% in caregivers. In 35 dyads (15.6%) both the patient and caregiver reported depressive symptoms in the clinical range. We found that high levels of fatigue (Beta = -0.116; OR = 0.890; 95% CI, 0.848-0.935; p = <0.001) and perceived stress (Beta = 0.198; OR = 1.219; 95% CI, 1.127-1.318; p = <0.001) were predictive of depressive symptoms in patients. Poor quality of life (Beta = 0.067; OR = 1.069; 95% CI, 1.040-1.099; p = <0.001) was a significant predictor of depressive symptoms in cancer caregivers. We found that depressive symptoms did not predict immune system parameters in either patients or caregivers after adjusting for sociodemographic factors and psychosocial and behavioral covariates. Conclusions: This one of a limited number of studies to examine the predictors of depression for patients and caregivers in the context of the dyad. Due to the high rates of depression observed, psychosocial interventions designed to target the predictors, for patients and caregivers, is recommended.