Higher serum vitamin B6 is associated with lower all-cause mortality among cancer survivors in the National Health and Nutrition Examination Survey

Abstract

Variations in serum concentrations of vitamin B₆, vitamin B₁₂, and folate may influence cancer development and progression. However, the association between these 3 serum B vitamins and all-cause mortality among cancer survivors remains unclear. We evaluated the potential associations between serum vitamins B₆, B₁₂, and folate and all-cause mortality among cancer survivors. Our hypothesis proposed that higher serum concentrations of vitamin B₆, vitamin B₁₂, and folate might be inversely associated with a lower risk of all-cause mortality in this population. Data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018 were used. All-cause mortality was determined by linking participant data to National Death Index records till 31 December 2019. Serum vitamins B₆, B₁₂, and folate status were measured. Multivariable Cox regression analyses were applied to investigate the relationship between serum vitamins B₆, B₁₂, and folate concentrations and all-cause mortality among cancer survivors. Serum vitamin B₆ was inversely associated with all-cause mortality, with a fully-adjusted HR of 0.54 (95%CI: 0.38, 0.78, P _trend< .001). However, no statistically significant association was observed between serum vitamin B₁₂ as well as serum folate concentration and all-cause mortality among cancer survivors (B₁₂: fully-adjust HR = 0.90, 95%CI: 0.63, 1.27, P _trend = .771; folate: fully-adjust HR = 0.82, 95%CI: 0.63, 1.08, P _trend = .269). No statistically significant interaction for age, sex, and BMI was found in stratified analyses. No non-linear relationship was found except for serum folate. These results suggest that higher serum vitamin B₆ may be associated with improved survival in cancer survivors.