Background
Up to 50% of prostate cancer (PC) patients receive androgen deprivation therapy (ADT), often for several years.
Although depression has been reported after a diagnosis of PC, and men on ADT describe emotional lability and depressed mood, it is not clear whether ADT actually leads to or worsens depression.
The few other studies addressing this question often included only men with advanced disease and had various methodological problems, thereby limiting the interpretation of findings.
Aim
To assess depressive symptoms and incident depression (Geriatric Depression Scale (GDS) score >=5) in a prospective matched cohort study of men with non-metastatic prostate cancer and two control groups.
Methods
Three groups were assembled: ADT users (men initiating continuous ADT), PC controls (PC patients who were not on ADT), and healthy controls. All three cohorts were matched on age, education, and physical function, and none had metastases.
Depression was measured at study entry and again at 3, 6, and 12 months using the 15-item Geriatric Depression Scale (GDS). The GDS has been validated in middle-aged and older adults.
The primary outcomes were worsening depressive symptoms and incident depression (defined as a GDS score ≥5), analyzed using adjusted linear regression and logistic regression, respectively.
Results
Of the 257 participants (mean age 69.1 years; range 60-80 years), baseline characteristics including GDS score and prior depression were similar across cohorts.
In adjusted analyses of initially non-depressed patients, ADT use was not a significant predictor of change in GDS score at 3 months (P = 0.42), 6 months (P =0.25), or 12 months (P = 0.19). Among ADT users, 8%-9% of participants developed incident depression compared with 0%-4% among PC controls and 4%-6% among healthy controls over 3-12 months (P>0.05 at all time points).
In a separate analysis of patients with depression at baseline, there was no effect of ADT on depressive symptoms at 3, 6, or 12 months (P = 0.11, 0.74, and 0.12, respectively).
Conclusion
Using ADT for up to 12 months was not associated with worsening depressive symptoms among non-depressed or depressed patients with non-metastatic PC.
