Objective: Although some studies have demonstrated the association of psychological distress and diminished immune system function in HIV spectrum disease, other studies have yielded apparently conflicting findings; the lack of consideration of the role of HIV viral burden may be central to this controversy. This study examined whether HIV viral burden moderated the relationship between psychological distress and enumerative and functional immune measures in pre-AIDS HIV spectrum disease.
Methods: This cross-sectional study used factor analysis to derive a composite measure of psychological distress incorporating measures of dysphoria, anxiety, and perceived stress. Multiple regression analyses used distress as the predictor, immune measures as the outcome variables, with viral load as the moderator variable, while controlling for age, medication use, and HIV symptomatology. Subjects were 148 pre-AIDS, HIV seropositive men and women (89 asymptomatic, 59 symptomatic), aged 18 to 45 years. The main outcome measures were enumerative and functional immune measures.
Results: A model of psychological distress was derived using each of the proposed measures. Findings indicated that high distress was associated with decreased numbers of helper T (memory) cells and B cells, but only at low levels of viral burden after controlling for age, medication use, and HIV-related symptoms.
Conclusions: These findings highlight the importance of assessing the role of HIV viral burden when examining distress-immunity relationships in HIV-infected individuals. The lack of association in those persons with high viral load suggests that, even before AIDS onset, disease-related processes are disrupting CNS and immune system communication.