Major depression and generalized anxiety disorder among human T-lymphotropic virus types I- and II-infected former blood donors

Background: Other studies have reported high rates of depression and anxiety among human T-lymphotropic virus Type I (HTLV-I)-infected subjects and have even suggested that HTLV-I causes psychiatric disease.

Study design and methods: We interviewed HTLV-I, HTLV-II, and demographically similar HTLV-seronegative blood donors with the Mini-International Neuropsychiatric Interview. Prevalences of major depression and generalized anxiety disorder in each group were calculated and compared to published US population data. Adjusted odds ratios (aOR) and 95% confidence intervals (CIs) controlling for educational achievement, alcohol intake, and self-reported health status were calculated with multivariate logistic regression.

Results: Major depression was diagnosed in five (5.4%) of 93 HTLV-I-positive subjects (aOR, 2.19; 95% CI, 0.63-7.55) and 17 (6.6%) of 256 HTLV-II-positive subjects (aOR, 1.61; 95% CI, 0.66-3.927), compared to 12 (2.1%) of 585 HTLV-seronegative blood donors. The prevalence of major depression among infected subjects was comparable to the 6.7% prevalence in the US general population. Generalized anxiety disorder was diagnosed in five (5.4%) HTLV-I-positive subjects (OR, 2.32; 95% CI, 0.74-7.26) and 12 (4.7%) HTLV-II-positive subjects (OR, 1.65; 95% CI, 0.68-4.01), compared to 15 (2.6%) seronegative subjects and 3.1% in the US general population.

Conclusion: Major depression and generalized anxiety disorder were not significantly more prevalent among HTLV-I- and HTLV-II-infected former blood donors after controlling for health status and other confounding variables. HTLV-seronegative blood donors had lower prevalences of these conditions than the US population, probably due to a "healthy blood donor effect."