Safety and effectiveness of vitamin D mega-dose: A systematic review

Prospective pilot study evaluating a vitamin D3 loading dose in critically ill children with vitamin D deficiency

BACKGROUND

Vitamin D deficiency is a common finding in critically ill children. However, the optimal supplementation strategy in this patient population is unknown. The objective of this study was to evaluate the effects of high-dose (10 000 IU/kg, max. 400 000 IU) vitamin D supplementation on 25-hydroxyvitamin D3 (25[OH]D3) levels in pediatric intensive care unit (PICU) patients with baseline vitamin D deficiency.

METHODS

This was a prospective, institutional review board-approved pilot research study performed at the University of South Alabama Women's and Children's Hospital in Mobile, AL. The study sample consisted of patients less than 18 years old admitted to the PICU with baseline 25-hydroxyvitamin D (25[OH]D) level less than 30 ng/ml. Included patients received a one-time dose of vitamin D3 orally or via gastric tube (10 000 IU/kg, max. 400 000 IU).

RESULTS

A total of 17 patients were screened with 11 included in the study. Blood analysis revealed a significant increase in 25(OH)D3 level from baseline to 12-h post dose (21.6 [4.5] ng/ml vs. 46.7 [15.5] ng/ml, P < 0.001). At the 12-h post-dose time point, 10/11 patients (91%) had 25(OH)D3 levels that were greater than 30 ng/ml. No adverse effects were observed.

CONCLUSION

Vitamin D3 supplementation at a dose of 10 000 IU/kg (max. 400 000 IU) significantly increased 25(OH)D3 levels in critically ill pediatric patients.

Vitamin D loaded into lipid nanoparticles shows insulinotropic effect in INS-1E cells

Increasing evidence suggests a beneficial role of vitamin D (VitD) supplementation in addressing the widespread VitD deficiency, but currently used VitD3 formulations present low bioavailability and toxicity constrains. Hence, poly(L-lactide-co-glycolide) (PLGA) nanoparticles (NPs), solid-lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) were investigated to circumvent these issues. PLGA NPs prepared by emulsification or nanoprecipitation presented 74 or 200 nm, and association efficiency (AE) of 68 % and 17 %, respectively, and a rapid burst release of VitD3. Both SLN and NLCs presented higher polydispersity and larger NPs size, around 500 nm, which could be reduced to around 200 nm by use of hot high-pressure homogenization in the case of NLCs. VitD3 was efficiently loaded in both SLNs and NLCs with an AE of 82 and 99 %, respectively. While SLNs showed burst release, NLCs allowed a sustained release of VitD3 for nearly one month. Furthermore, NLCs showed high stability with maintenance of VitD3 loading for up to one month at 4 °C and no cytotoxic effects on INS-1E cells up to 72 h. A trending increase (around 30 %) on glucose-dependent insulin secretion was observed by INS-1E cells pre-treated with VitD3. This effect was consistently observed in the free form and after loading on NLCs. Overall, this work contributed to further elucidation on a suitable delivery system for VitD3 and on the effects of this metabolite on β cell function.

Treatment of vitamin D deficiency in children

INTRODUCTION

Vitamin D deficiency affects from 10% to 50% in various pediatric population groups and causes life-threatening hypocalcemia in infants, crippling rickets in infants and children, and increased risk of subsequent adult metabolic and neurologic problems.

AREAS COVERED

An English language literature search of PubMed was performed since 1940 as were the authors' personal literature collections. References identified in the reviewed literature are considered.

DIAGNOSIS

The diagnosis of vitamin D deficiency is based on serum 25-hydroxyvitamin D levels. Clinical features of rickets include bone deformities and elevated alkaline phosphatase. Most children and adolescents who are biochemically vitamin D deficient do not have specific symptoms or signs of deficiency.

PREVENTION

Prevention of vitamin D deficiency is via exposure to sunshine, food and beverage fortification, and dietary supplementation.

TREATMENT

Effective treatment of vitamin D deficiency is via oral or injectable administration of vitamin D. Dosing and duration of vitamin D therapy have been described for healthy children and for children with underlying medical conditions, but recommendations vary.

EXPERT OPINION

Further investigation is needed to determine long-term non-skeletal effects of childhood vitamin D deficiency, benefits of supplementation in asymptomatic individuals with biochemical vitamin D deficiency, and appropriate screening for vitamin D deficiency in asymptomatic children and adolescents.

Optimal vitamin D status at admission appears to improve survival after craniotomy in patients with brain malignancies

BACKGROUND AND AIMS

Survival from diagnosis of brain malignancies is often very short. Craniotomy in turn may be associated with morbidity and even post-operative mortality. Vitamin D and calcium were known as protective factors on all-cause mortality. However, their role is not well-understood in post-surgery survival of brain malignant patients.

METHODS

Totally, 56 patients completed the present quasi-experimental study, comprising the intervention group (n = 19) under intramuscular administration of 300 000 IU vitamin D3, the control group (n = 21), and the group of patients with optimal vitamin D status at admission (n = 16).

RESULTS

The mean ± SD of preoperative 25(OH)D levels in the control, intervention, and optimal vitamin D status groups were 15.15 ± 3.63 ng/mL, 16.61 ± 2.56 ng/mL, and 40.03 ± 10.56 ng/mL, respectively (P < 0.001). Crude survival was significantly greater in the optimal vitamin D status group than those in another two groups (P = 0.005). Also, Cox proportional hazard model showed that the risk of mortality was higher in the control group and the intervention group than in the group of patients with optimal vitamin D status at admission (P-trend = 0.03). However, this correlation weakened in the full-adjusted models. Preoperative total calcium had an inverse significant correlation with mortality risk [HR value 0.25, (95%, CI: 0.09-0.66), P = 0.005], and age had a positive correlation [HR value 1.07, (95%, CI: 1.02-1.11), P = 0.001].

CONCLUSION

Total calcium and age were predictive factors in six-month mortality and optimal vitamin D status appears to improve the survival in these patients, which should be examined more closely in future studies.

Effect of Single High Dose Vitamin D Substitution in Hospitalized COVID-19 Patients with Vitamin D Deficiency on Length of Hospital Stay

Vitamin D and its role in the coronavirus-19 disease (COVID-19) pandemic has been controversially discussed, with inconclusive evidence about vitamin D3 (cholecalciferol) supplementation in COVID-19 patients. Vitamin D metabolites play an important role in the initiation of the immune response and can be an easily modifiable risk factor in 25-hydroxyvitamin D₃ (25(OH)D₃)-deficient patients. This is a multicenter, randomized, placebo-controlled double-blind trial to compare the effect of a single high dose of vitamin D₃ followed by treatment as usual (TAU) of daily vitamin D₃ daily until discharge versus placebo plus TAU in hospitalized patients with COVID-19 and 25(OH)D₃-deficiency on length hospital stay. We included 40 patients per group and did not observe a significant difference in the median length of hospital stay (6 days in both groups, p = 0.920). We adjusted the length of stay for COVID-19 risk factors (β = 0.44; 95% CI: -2.17-2.22), and center (β = 0.74; 95% CI: -1.25-2.73). The subgroup analysis in patients with severe 25(OH)D₃-deficiency (<25 nmol/L) showed a non-significant reduction in the median length of hospital stay in the intervention group (5.5 vs. 9 days, p = 0.299). The competing risk model with death did not reveal significant differences between the group in the length of stay (HR = 0.96, 95% CI 0.62-1.48, p = 0.850). Serum 25(OH)D₃ level increased significantly in the intervention group (mean change in nmol/L; intervention: +26.35 vs. control: -2.73, p < 0.001). The intervention with 140,000 IU vitamin D₃ + TAU did not significantly shorten the length of hospital stay but was effective and safe for the elevation of serum 25(OH)D₃ levels.

Vitamin D and COVID-19-Revisited

Vitamin D, when activated to 1,25-dihydroxyvitamin D, is a steroid hormone that induces responses in several hundred genes, including many involved in immune responses to infection. Without supplementation, people living in temperate zones commonly become deficient in the precursor form of vitamin D, 25-hydroxyvitamin D, during winter, as do people who receive less sunlight exposure or those with darker skin pigmentation. Studies performed pre-COVID-19 have shown significant but modest reduction in upper respiratory infections in people receiving regular daily vitamin D supplementation. Vitamin D deficiency, like the risk of severe COVID-19, is linked with darker skin colour and also with obesity. Greater risk from COVID-19 has been associated with reduced ultraviolet exposure. Various studies have examined serum 25-hydroxyvitamin D levels, either historical or current, in patients with COVID-19. The results of these studies have varied but the majority have shown an association between vitamin D deficiency and increased risk of COVID-19 illness or severity. Interventional studies of vitamin D supplementation have so far been inconclusive. Trial protocols commonly allow control groups to receive low-dose supplementation that may be adequate for many. The effects of vitamin D supplementation on disease severity in patients with existing COVID-19 are further complicated by the frequent use of large bolus dose vitamin D to achieve rapid effects, even though this approach has been shown to be ineffective in other settings. As the pandemic passes into its third year, a substantial role of vitamin D deficiency in determining the risk from COVID-19 remains possible but unproven.

Post-Diagnosis Vitamin D Supplement Use and Survival among Cancer Patients: A Meta-Analysis

Vitamin D administered pre-diagnostically has been shown to reduce mortality. Emerging evidence suggests a role of post-diagnosis vitamin D supplement intake for survival among cancer patients. Thus, we conducted a meta-analysis to evaluate the relationship. PubMed and Embase were searched for relevant observational cohort studies and randomized trials published through April 2022. Summary relative risk (SRR) and 95% confidence interval (CI) were estimated using the DerSimonian–Laird random-effects model. The SRR for post-diagnosis vitamin D supplement use vs. non-use, pooling cohort studies and randomized trials, was 0.87 (95% CI, 0.78–0.98; p = 0.02; I² = 0%) for overall survival, 0.81 (95% CI, 0.62–1.06; p = 0.12; I² = 51%) for progression-free survival, 0.86 (95% CI, 0.72–1.03; p = 0.10; I² = 0%) for cancer-specific survival, and 0.86 (95% CI, 0.64–1.14; p = 0.29; I² = 0%) for relapse. Albeit not significantly heterogeneous by variables tested, a significant inverse association was limited to cohort studies and supplement use during cancer treatment for overall survival, and to studies with ≤3 years of follow-up for progression-free survival. Post-diagnosis vitamin D supplement use was associated with improved overall survival, but not progression-free or cancer-specific survival or relapse. Our findings require confirmation, as randomized trial evidence was insufficient to establish cause-and-effect relationships.

Vitamin D Is Associated with Clinical Outcomes in Patients with Primary Biliary Cholangitis

Vitamin D (VD) deficiency has been associated with clinical outcomes in patients with chronic liver disease. This study aims to identify the prevalence of VD deficiency in patients with primary biliary cholangitis (PBC) and its association with treatment response to ursodeoxycholic acid (UDCA), cirrhosis development, and liver-related events (mortality and liver transplantation). Two hundred and fifty-five patients with PBC diagnosis were evaluated. Patients with VD levels below 50 nmol/L were defined as deficient. Treatment response to UDCA was defined according to the Toronto criteria. Independent risk factors were identified using binary logistic and Cox regression analysis. The mean level of serum VD was 77 ± 39 nmol/L, and 64 patients (25%) were VD deficient. Incomplete response to UDCA was more prevalent in VD-deficient patients compared to their counterparts (45% vs. 22%; p < 0.001). The risk of cirrhosis development (hazard ratio (HR) 1.93; 95% confidence interval (CI) 1.17–3.19, p = 0.01) and liver-related mortality or need for liver transplantation (HR 3.33, 95% CI, 1.57–7.07, p = 0.002) was higher in VD-deficient patients after adjusting for confounders. Vitamin D deficiency is frequent in patients with PBC and is associated with incomplete response to UDCA, cirrhosis development, and liver-related mortality or need for liver transplantation.

Association of weekly or biweekly use of 50.000 IU vitamin D3 with hypervitaminosis D

Since the beginning of COVID-19 pandemic, many Iranian people are taking 50.000 IU of vitamin D3 on the weekly or biweekly bases in order to enhance their immune system function. This cross-sectional study was conducted on the patients of endocrinology clinic to compare 25(OH)D levels of weekly or biweekly consumption with the monthly users of vitamin D3 50,000 IU. The level above 100ng/ml of 25(OH)D was defined as hypervitaminosis D. Totally, 211 patients (108 and 103 patients in monthly and weekly/biweekly groups, respectively) were studied. In the subgroups of weekly and biweekly users, the rates of hypervitaminosis were 18.9% and 4.5%, respectively. In contrast, only 0.9% of monthly users had hypervitaminosis D. The highest vitamin D value of 185 ng/ml was detected in a patient who consumed 50,000 IU vitamin D3 weekly for 6 years. No hypercalcemia was detected in the patients with hypervitaminosis D.