High doses of oral folate and sublingual vitamin B12 in dialysis patients with hyperhomocysteinemia

Role of Peritoneal Equilibration Test in Assessing Folate Transport During Peritoneal Dialysis

OBJECTIVES

Low plasma folate levels have been reported in patients undergoing hemodialysis and peritoneal dialysis (PD) in clinical studies. However, folate transport has never been mentioned as a factor contributing to low plasma folate levels in patients undergoing PD. The peritoneal equilibrium test (PET) assesses the plasma creatinine level and glucose transport abilities. This study aimed to evaluate the association between plasma folate levels and folate transport during PD based on PET grades.

METHODS

This study recruited 50 patients who underwent PD for ≥3 months and were categorized according to PET grades. Data regarding plasma folate levels and dialysate folate were collected. The primary outcomes were the relationship between the PET grade and plasma folate level and between the PET grade and dialysate-to-plasma folate concentration ratio (D/P folate). Furthermore, the difference in the plasma folate level and D/P folate between men and women was assessed.

RESULTS

The plasma folate level and the D/P folate significantly differed among the 4 PET groups (both P < .001). PET grade was significantly negatively correlated with plasma folate levels (r = -0.56, P < .001) and positively correlated with D/P folate (r = 0.686, P < .001). In subgroup analysis, neither the plasma folate level nor the D/P folate significantly differed between men and women.

CONCLUSIONS

Our study provides clinical evidence that the PET grade is associated with the plasma folate level and D/P folate, regardless of sex. Larger cohort studies are warranted to assess the importance of folate supplementation during PD based on PET grades.

Relationship between high dose intake of vitamin B12 and glaucoma: Evidence from NHANES 2005-2008 among United States adults

Objective

Glaucoma has currently become the second leading cause of blindness in the world. Serum vitamin B12 level has been found to be involved in the development and progression of glaucoma. We performed the present study to confirm this association.

Methods

This cross-sectional study included 594 participants aged 40 years and older in the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2008. Retinal imaging was performed using the Ophthalmic Digital Imaging system (Retinography) to assess the retina for the presence of features of glaucomatous lesions. Logistic regression models were used to assess the association between dietary vitamin intake and glaucoma.

Results

After screening, 594 subjects were finally included. Among all vitamin intakes, we observed significant differences between the two groups for vitamin B12 intake (5.93 vs. 4.77 mg, p = 0.033). According to the logistic regression results, the intake of vitamin B12 was significantly positively associated with glaucoma (model 1: OR = 1.078, 95% CI = 1.019-1.141; model 2: OR = 1.092, 95% CI = 1.031-1.158; model 3: OR = 1.092, 95% CI = 1.029-1.158). After performing a quantile regression, we observed a significant positive association between vitamin B12 intake and incident glaucoma in the fourth quartile (model 1: OR = 1.133, 95% CI = 1.060-1.210; model 2: OR = 1.141, 95% CI = 1.072-1.215; model 3: OR = 1.146, 95% CI = 1.071-1.226).

Conclusions

Therefore, the above results, high-dose intake of vitamin B12 may promote the development of glaucoma.

The role of vitamin B12 in viral infections: a comprehensive review of its relationship with the muscle-gut-brain axis and implications for SARS-CoV-2 infection

This comprehensive review establishes the role of vitamin B12 as adjunct therapy for viral infections in the treatment and persistent symptoms of COVID-19, focusing on symptoms related to the muscle-gut-brain axis. Vitamin B12 can help balance immune responses to better fight viral infections. Furthermore, data from randomized clinical trials and meta-analysis indicate that vitamin B12 in the forms of methylcobalamin and cyanocobalamin may increase serum vitamin B12 levels, and resulted in decreased serum methylmalonic acid and homocysteine concentrations, and decreased pain intensity, memory loss, and impaired concentration. Among studies, there is much variation in vitamin B12 doses, chemical forms, supplementation time, and administration routes. Larger randomized clinical trials of vitamin B12 supplementation and analysis of markers such as total vitamin B12, holotranscobalamin, total homocysteine and methylmalonic acid, total folic acid, and, if possible, polymorphisms and methylation of genes need to be conducted with people with and without COVID-19 or who have had COVID-19 to facilitate the proper vitamin B12 form to be administered in individual treatment.