Vitamin B-6 and depressive symptomatology, over time, in older Latino adults

Abstract

Background: Low vitamin B-6 status has been linked to depressive symptomatology. We examined the longitudinal association of vitamin B-6 status with depressive symptomatology across 3-time points over ∼5-7 years in a cohort of older Hispanic adults. Methods: We used two-level hierarchical linear regression models for continuous outcomes. Vitamin B-6 status was associated with depressive symptomatology across these time points. Results: Plasma pyridoxyl-5-phosphate (PLP) concentration, a time-varying predictor, was significantly associated with depressive symptomatology. Study participants with PLP deficiency, vs. optimal PLP, had higher baseline depressive symptoms (Center for Epidemiologic Studies-Depression Scale (CES-D) score of 22 ± 14, vs. 20 ± 13); this differential remained constant over time and persisted after controlling for age, sex, education, body mass index, smoking and alcohol use, other relevant nutritional factors, perceived stress, stressful life events, allostatic load, and use of antidepressant medication. However, PLP concentration was not associated with the rate of change in depressive symptomatology over time. Conclusions: Suboptimal plasma PLP is associated with higher depressive symptomatology in older Hispanic of Puerto Rican descent and this appears to persist over time. Our data suggest that identification and treatment of vitamin B-6 deficiency may be a useful preventive approach in this population.

Keywords: Depressive symptoms; Longitudinal association; Older Latino adults; Plasma PLP; Vitamin B-6 deficiency.

Conflict of interest statement

Conflict of interest: All authors declare no conflicts of interest to disclose.

Figures

Figure 1.

Flow diagram of participants included in the current analysis. 1 Identified as of Puerto Rican descent. 2 Met the exclusion criteria (eg, serious illness, moved from the study area, homeless, or hostile). 3 Reasons for declining participation (eg, not interested, too busy, did not want blood drawn, length of study, or doctor/spouse advised against participation). 4 Low Mini-Mental State Examination Score (MMSE<10). 5 Participants with valid depressive symptomatology and plasma PLP data. 6 Baseline participants with 2y follow-up data. 7 Baseline participants with 5y follow-up data.

Figure 2.

Longitudinal change in depressive symptomatology by PLP status after adjusting for age, sex, education, BMI, smoking and alcohol use; perceived stress, stressful life events, and allostatic load; micronutrients including plasma vitamin B-12, folate, D, energy adjusted dietary intake of magnesium and antidepressant medication use.