Post-traumatic Disorder Symptoms and Blunted Diurnal Cortisol Production in Partners of Prostate Cancer Patients

Prostate cancer (PC) is the most common cancer diagnosed in men, and research suggests that coping with this illness can cause significant distress in patients as well as their partners. This study examined the relationship of caregiving for a partner with PC with diurnal cortisol output in women between the ages of 42 and 75 years old. Participants were women whose partners had PC (n = 19) and women who were in relationships with men with no diagnosed medical illness (n = 26). Women provided saliva samples (4 times per day over 3 days) in their natural environment. The Structured Clinical Interview for DSM-IV Axis-I Disorders was also conducted to assess for the presence of post-traumatic stress disorder (PTSD) and major depression. Partners of men with PC had lower daily cortisol output across the three days than controls, F(1,444.08) = 20.72, p<.001). They were also more likely to report PTSD symptoms with 68.4% of PC partners fulfilling criteria for sub-threshold PTSD as compared to 23.1% of controls (χ(2) = 11.30, p = .01). Mixed model analyses revealed that the presence of sub-threshold PTSD symptoms significantly predicted cortisol production, F(1,419.64) = 5.10, p<.01). Regardless of caregiver status, women who reported at least sub-threshold PTSD symptoms had lower cortisol production than those with no PTSD symptoms. Major depression did not explain differences in cortisol production between partners of PC patients and controls. Although these findings are preliminary, they highlight the importance of developing interventions aimed at reducing risk of psychopathology in partners of men with PC.