Major depression and generalized anxiety disorder among HTLV-I/II infected former blood donors

Background

Other studies have reported high rates of depression and anxiety among human T-lymphotropic virus type 1 (HTLV-1) infected subjects, and have even suggested that HTLV-I causes psychiatric disease.

Methods

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

Results

Major depression was diagnosed in 5 (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 0.66-3.92), 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 U.S. general population. Generalized anxiety disorder was diagnosed in 5 (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%) seronegatives and 3.1% in the U.S. general population.

Conclusion

We observed slightly higher prevalence of major depression and generalized anxiety disorder among HTLV-I and HTLV-II subjects that was not significantly elevated after controlling for health status and other confounding variables. Comparison to U.S. population data suggested that these findings are in part explained by a “healthy blood donor effect” among our controls.