The differential impact of PTSD and depression on HIV disease markers and adherence to HAART in people living with HIV.

Despite high rates of comorbidity, research has typically focused on the independent impact of posttraumatic stress disorder (PTSD) and depression symptoms in people living with HIV (PLWH). The present study examined the independent and comorbid influence of PTSD and depression symptoms on medication adherence, CD4 cell counts, and viral load, over the course of 3 months in 57 PLWH (82% men, 54% Caucasian, 44% African American) recruited from a clinic or social service agency. Both PTSD and depressive symptoms predicted lower subsequent adherence. However, only depressive symptoms predicted lower CD4 counts and presence of a detectable viral load. Participants reporting symptoms consistent with diagnostic levels of comorbid PTSD and depression were less likely to adhere to HAART and were more likely to have a detectable viral load. These results highlight the influences of PTSD and depression on adherence and HIV disease markers, and underscore the importance of examining comorbid symptomatology in PLWH.