Impact of Vitamin B6 Status on Psychological Distress in a Longitudinal Study of HIV-1 Infection

Abstract

Objective: Inadequate vitamin B6 status has been associated with altered neuropsychiatric function, possibly through its effect on the metabolism of neurotransmitters, including serotonin (5-HT). The present eighteen month longitudinal study evaluated the relationship between vitamin B6 status and psychological distress in HIV-1 infected individuals, controlling for the influence of negative life events, social support and coping style. Method: Biochemical measurements of nutritional status, and dietary intake evaluations were obtained in HIV-1 seropositive homosexual men, (at baseline: CDC Stages II and III, n = 70; Stage IVA, IVC2 n = 18) at six month intervals. Alterations in nutrient status (e.g., vitamin B6 adequate to inadequate; inadequate to adequate), were compared with changes in psychological distress, measured by the Profile of Mood States, using a multiple regression analysis. Results: A significant decline in psychological distress was demonstrated with normalization of vitamin B6 status from inadequate to adequate status ( p < 0.02). A decrease in psychological distress was also observed with increased tryptophan intake in subjects who were vitamin B6 adequate ( p < 0.02). Conclusions: Significant effects for the nutritional variables remained even when negative life event stressors, social support, and coping style were controlled, suggesting that vitamin B6 status may be an important co-factor in determining level of psychological distress over time in HIV-1 infected individuals.