Vitamin B6 is associated with depressive symptomatology in Massachusetts elders

We examined the cross-sectional relationship between dietary vitamin B6 and plasma pyridoxyl-5'-phosphate concentrations (PLP) with depressive symptomatology among a representative sample of 618 elderly Caribbean Hispanics, and a neighborhood based comparison group of 251 non-Hispanic white (NHW) older adults in Massachusetts.

Depressive symptomatology was assessed with the Center for Epidemiologic Studies Depression Scale (CES-D). 41% of Hispanics and 22.6% of NHWs had CES-D scores greater than 16, indicating depressive caseness. Dietary intake was calculated from a semi-quantitative food frequency questionnaire (FFQ) designed for this population.

PLP was significantly associated with CES-D score and depressive caseness in the total sample and in non-supplement users. Deficient levels of plasma PLP (plasma PLP < 20 nmol/L) approximately doubled the likelihood of depressive caseness. Total intake (diet + supplement) of vitamin B(6) was not associated with these outcomes. However, dietary vitamin B(6) was significantly associated with CES-D score and depressive caseness.

Longitudinal studies are needed to clarify the direction of causality between vitamin B6 and depressive symptoms.