Reported rates of depression among people infected with HIV vary. During the course of their disease, up to 85% of HIV-seropositive individuals report some depressive symptoms, and up to 50% experience a major depressive disorder. The variability across studies may be due to small sample size, population characteristics, and evaluation tools. However, in their meta-analysis of published studies, Ciesla and Roberts (2001) found that people with HIV were almost twice as likely as those who are HIV-seronegative to be diagnosed with major depressive disorder, and that depression was equally prevalent in people with both symptomatic and asymptomatic HIV. In their recent analysis of rates of depression and anxiety disorders in people with HIV, Morrison et al. (2002) found a fourfold increase in the risk of current major depressive disorder in HIV-seropositive women compared with an HIV-seronegative group.
The data regarding the prevalence of mania in people with HIV is scant. Although less common than depression, the risk of mania is still thought to be significant, particularly as the disease progresses (Ellen et al., 1999). Mania may be the behavioral manifestation of direct central nervous system (CNS) pathology or toxicity or, if the patient has a family or personal history of bipolar disorder, mania may suggest a primary affective disorder.
The occurrence of psychosis is not too surprising since people with HIV experience marked disturbances in dopamine metabolism (Berger et al., 1994). Early samples found frequencies ranging between less than 0.5% to 15% (Sewell et al. 1994).