Association of Serum Vitamin B6 with All-Cause and Cause-Specific Mortality in a Prospective Study

Dietary vitamin B6 intake and stroke are negatively associated in adults: A cross-sectional study from the NHANES

Background

The relationship between dietary vitamin B6 and stroke risk is controversial; thus, we analyzed their correlation using data from the National Health and Nutrition Examination Survey (NHANES).

Method

Data from 2005 to 2018 were collected from the NHANES database. Two 24-h dietary recalls and a standard questionnaire were used to evaluate vitamin B6 intake and stroke prevalence. We used logistic regression models to estimate the association between dietary vitamin B6 intake and stroke risk and investigated the nonlinear relationship between them using a restricted cubic spline (RCS). Sensitivity analysis was conducted using propensity score matching (PSM).

Results

Among 24,214 participants, 921 were patients diagnosed with stroke, while 23,293 were without stroke. The multivariate logistic regression model revealed that individuals in the highest quartile of vitamin B6 consumption had a significantly lower stroke risk than those in the lowest quartile under the fully adjusted model (OR: 0.48, 95 % CI: 0.35-0.66, P < 0.001). Subgroup analyses showed that dietary intake of vitamin B6 was a significant protective factor against stroke risk in different populations, with the most pronounced effect in the population engaging in moderate-intensity physical activity (OR: 0.34, 95%CI: 0.20-0.57). The RCS models revealed a non-linear L-shaped relationship (P for nonlinearity = 0.006) between stroke and dietary intake of vitamin B6.

Conclusions

Our study shows that an increased intake of vitamin B6 could be an effective strategy in reducing the risk of stroke.

Associations of serum vitamin B6 status with the risks of cardiovascular, cancer, and all-cause mortality in the elderly

Background

There are few studies investigating the relationship between serum vitamin B6 and mortality risk in the elderly. This study hereby evaluated the associations between biomarkers of serum vitamin B6 status and cardiovascular, cancer, and all-cause mortality risks in the elderly.

Methods

Our study included a total of 4,881 participants aged 60 years or older from the National Health and Nutrition Examination Survey (NHANES) 2005-2010. Serum vitamin B6 status was estimated based on levels of pyridoxal 5'-phosphate (PLP), 4-pyridoxic acid (4-PA), and vitamin B6 turnover rate (4-PA/PLP) detected by high-performance liquid chromatography. Survival status and corresponding causes of death were matched through the National Death Index records through December 31, 2019. Multivariate Cox regression model was adopted to assess the relationships between serum vitamin B6 status and the risk of mortality.

Results

During a median follow-up period of 10.33 years, 507 cardiovascular deaths, 426 cancer deaths, and 1995 all-cause deaths were recorded, respectively. In the multivariate-adjusted Cox model, the hazard ratios (HRs) and 95% confidence intervals (CIs) for the highest versus the lowest quartiles of PLP, 4-PA, and 4-PA/PLP were 0.70(0.54-0.90), 1.33(0.88-2.02), and 2.01(1.41-2.79) for cardiovascular mortality, 0.73(0.52-1.02), 1.05(0.71-1.57), and 1.95(1.25-3.05) for cancer mortality, and 0.62(0.53-0.74), 1.05(0.82-1.34), and 2.29(1.87-2.79) for all-cause mortality, respectively.

Conclusion

Our study found that lower serum PLP levels were associated with increased risks of cardiovascular and all-cause mortality among the elderly population. And higher vitamin B6 turnover rate was associated with increased risks of cardiovascular, cancer, and all-cause mortality.

Relationship of Low Vitamin B6 Status with Sarcopenia, Frailty, and Mortality: A Narrative Review

Marginal vitamin B6 (B6) deficiency is a widespread global concern. Inadequate B6 levels have been linked to an increased risk of age-related chronic diseases such as cardiovascular diseases and cancers. In recent years, the growing concern over sarcopenia (the age-related loss of muscle mass and strength) and frailty (a decline in physiological resilience and increased vulnerability associated with aging) is particularly relevant due to the emergence of super-aged societies in developed countries. Notably, among the thirty-one studies included in this review, twenty-five showed a significant association of B6 status with sarcopenia, frailty, and all-cause mortality in adults (p < 0.05), while six showed no association. Emerging studies have suggested novel mechanisms underlying this association. These mechanisms involve P2X7 receptor-mediated NLRP3 inflammasome signaling, AMPK signaling, PD-L1 signaling, and satellite cell-mediated myogenesis. Furthermore, the modulation of PLP-dependent enzymes due to B6 deficiency is associated with impaired metabolic processes, affecting energy utilization, imidazole peptide production, and hydrogen sulfide production, as well as the kynurenine pathway, all of which play vital roles in skeletal muscle health and pathophysiology. This narrative review provides an up-to-date assessment of our current understanding of the potential role of nutritional B6 status in combating sarcopenia, frailty, and mortality.

Association of B vitamin intake and total homocysteine levels with all-cause and cause-specific mortality in central obesity

OBJECTIVES

Future primary prevention strategies may benefit from understanding the connection between mortality in individuals with central obesity and modifiable lifestyle factors like dietary intake. This study sought to determine whether there was a separate relationship between folate, vitamin B6, and vitamin B12 intake and all-cause and cause-specific mortality in the US population with central obesity.

METHODS

The study analyzed data from the National Health and Nutrition Examination Survey between 1999 and 2016. Using the Cox proportional hazards model, the association between dietary intake of B vitamins and all-cause and cause-specific mortality was examined. A total of 7718 adults with central obesity were enrolled, with a mean age of 49.87 (SD = 0.25) y at baseline.

RESULTS

Folate intake was independently associated with a decreased incidence of all-cause mortality (adjusted hazard ratio = 0.71; 95% CI, 0.58-0.87). Furthermore, higher intake of vitamin B6 and vitamin B12 was inversely correlated with cardiovascular disease mortality (adjusted hazard ratio = 0.63; 95% CI, 0.40-0.98; and adjusted hazard ratio = 0.44; 95% CI, 0.29-0.65, respectively) and the finding reveal an interaction between homocysteine and vitamin B12 and folate on All-cause mortality CONCLUSIONS: The findings of this study suggest that vitamin B12 and folate intake may be protective factors in individuals with central obesity. It is important to consider both their total homocysteine level and body mass index in conjunction with these nutrients. Further research is needed to validate these findings.

Pyridoxine Deficiency and Neurologic Dysfunction: An Unlikely Association

Pyridoxine deficiency is a prevalent condition in the United States that primarily affects patients with alcohol use disorder. The presentation of this condition is very nonspecific and commonly presents with a constellation of symptoms including peripheral neuropathy, stomatitis, dermatitis, confusion, depression, encephalopathy, and seizures. Over half of these patients have associated alcohol use disorder, which causes pyridoxine deficiency due to the breakdown of pyridoxal phosphate during ethanol metabolism in the liver. As an important cofactor in the synthesis of γ-aminobutyric acid (GABA), deficient levels of pyridoxine may lower the seizure threshold due to reduced GABA-mediated inhibition. This case details a 57-year-old male with chronic alcoholism and a history of seizures who developed episodes of myoclonic jerks, tremors, anxiety, and neuropathy whose symptoms persisted even while on anti-epileptic medication. He was found to have pyridoxine deficiency and had full resolution of symptoms shortly after the administration of vitamin B6 supplementation. Pyridoxine deficiency may lead to severe neurologic disorders such as encephalopathy and seizures. Hence, it is important to consider pyridoxine deficiency in the workup of neurologic complaints, especially in high-risk patients.

Associations of vitamin B6 turnover rate with the risk of cardiovascular and all-cause mortality in hypertensive adults

BACKGROUND AND AIM

This study was to assess the association between vitamin B6 turnover rate and mortality in hypertensive adults.

METHODS AND RESULTS

Vitamin B6 status including serum pyridoxal-5'-phosphate (PLP) levels, serum 4-pyridoxal acid (4-PA) levels, and vitamin B6 turnover rate (4-PA/PLP) were obtained from the 2005-2010 National Health and Nutrition Examination Survey (NHANES) dataset of hypertensive adults with follow-up through December 30, 2019. Using Cox proportional risk regression models, Hazard ratios (HRs) and 95% confidence intervals (CIs) were analyzed for PLP, 4-PA and 4-PA/PLP quartiles in relation to cardiovascular and all-cause mortality. A total of 5434 participants were included in this study (mean age, 58.48 years; 50.4% men), and the median 4-PA/PLP was 0.75. The median follow-up time was 11.0 years, with 375 and 1387 cardiovascular and all-cause deaths, respectively. In multivariate COX regression models, PLP was negatively associated with cardiovascular mortality (HR [95% CI] quartile 4 vs. 1: 0.66 [0.47-0.94], P_trend = 0.03) and 4-PA/PLP was positively associated with cardiovascular mortality (HR [95% CI] quartile 4 vs.1: 1.80 [1.21-2.67], P_trend = 0.01). Similarly, the higher the quartile of PLP, the lower the risk of all-cause mortality (HR [95% CI] quartile 4 vs. 1: 0.67 [0.56-0.80], P_trend < 0.01). The higher the quartile of 4-PA and 4-PA/PLP, the higher the risk of all-cause mortality (HR [95% CI] quartile 4 vs. 1: 1.22 [1.01-1.48], P_trend < 0.01; and 2.09 [1.71-2.55], P_trend < 0.01).

CONCLUSION

The findings suggested that higher vitamin B6 turnover rate was associated with an increased risk of cardiovascular and all-cause mortality in hypertensive adults.