Effect of vitamin D supplementation on health status in non-vitamin D deficient people with type 2 diabetes mellitus

Influence of Vitamin D Supplementation on Mental Health in Diabetic Patients: A Systematic Review

Diabetes is associated with a number of mental health consequences, including enhanced risk of depression and anxiety, as well as decreased quality of life, and vitamin D deficiency is considered to be one of the factors that influence these outcomes in diabetic patients. The aim of the present study was to conduct a systematic review of the literature presenting the data regarding the influence of vitamin D supplementation on mental health in diabetic adults. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (Registration number CRD42020155779). A systematic search of the PubMed and Web of Science databases was performed, and the intervention studies published until September 2021 were included in the review. The human studies were included if an adult sample of diabetic individuals received vitamin D supplementation during the intervention and its effect on any mental health aspect was assessed, but studies presenting the influence of combined supplementation of multiple nutrients were excluded. After removing duplicate records, a total of 8514 publications were screened and assessed independently by two researchers, based on their title, abstract, and full text. Finally, six studies were included in the current systematic review, and the risk of bias was evaluated using the Newcastle–Ottawa Scale (NOS). The included studies analyzed the influence of a specific dose of vitamin D, or different doses of vitamin D, or compared the results of supplementation with a specific dose of vitamin D against the placebo group. The supplementation was performed for at least 12 weeks. The mental health outcomes analyzed in these studies included health-related quality of life, depression, anxiety, stress, and general mental health status of adult diabetic patients. The results of the majority of the studies confirmed the positive influence of vitamin D supplementation on the mental health of diabetic individuals. Those studies that analyzed the influence of vitamin D supplementation on depression and anxiety established the beneficial effect of the vitamin. In some studies, the influence of vitamin D supplementation on the health-related quality of life was not considered unless combined with mindfulness training. However, it must be emphasized that different dosage regimens and intervention periods were followed in the reviewed studies, and only a small number of studies were randomized against placebo, which should be considered as a limitation of the present study. The findings of the conducted systematic review demonstrated the positive influence of vitamin D supplementation on the mental health of diabetic patients, which was proved for anxiety and depression, but in the case of health-related quality of life, the positive effect was observed only when the intervention included mindfulness training. These outcomes suggest that supplementation should be recommended to improve the vitamin D status and the mental health of patients in this group.

Efficacy of Vitamin D Supplementation in Addition to Aerobic Exercise Training in Obese Women with Perceived Myalgia: A Single-Blinded Randomized Controlled Clinical Trial

Obese women were more susceptible to myalgia because of their significantly lower vitamin D concentrations; the present study investigated the efficacy of vitamin D in addition to an aerobic interval training in the management of obese women with myalgia. Forty-five obese women with vitamin D deficiency and myalgia (30 to 40 years old) were assigned randomly into three equal groups. Group A received an aerobic interval training with vitamin D supplementation, Group B received vitamin D supplementation only, and Group C received aerobic interval training only; participants in all groups were on calorie deficient diets. The study outcomes were the Visual Analog Scale (VAS) for Pain Evaluation, serum vitamin D level, and Cooper 12-Minute Walk Test for Functional Capacity Evaluation, while the Short-Form Health Survey (SF) was used for assessment of quality of life. We detected a significant improvement in pain intensity level, serum vitamin D level, and quality of life in all groups with significant difference between Group A and groups B and C. We also detected a significant improvement in functional capacity in groups A and C, with no significant change in Group B. Aerobic interval training with vitamin D supplementation was more effective for the management of obese women with perceived myalgia.

The relationship between serum 25-hydroxy vitamin D and blood pressure and quality of life in overweight and obese patients with type 2 diabetes mellitus compared with healthy subjects

Background:

Vitamin D is one of the known lipoprotein hormones with metabolic properties. We aimed to determine the serum 25-hydroxy vitamin D concentration in overweight/obese subjects with diabetes mellitus type Ⅱ (DM Ⅱ) in association with systolic and diastolic blood pressure and quality of life compared with healthy participants.

Methods:

The current case-control study was carried out among 80 overweight/obese subjects with DM Ⅱ, and 77 healthy subjects matched by sex, age and body mass index (BMI). Serum 25-hydroxyvitamin D concentration was measured by ELISA method. In order to examine the quality of life, the Persian version of SF36 questionnaire was used.

Results:

There was significant difference between diabetic and healthy subjects considering serum 25-hydroxyvitamin D concentration (p=0.012). Serum 25-hydroxyvitamin D concentration was inversely correlated with diastolic blood pressure (p=0.02) and positively associated with physical function (p<0.001), social function (p<0.001) and general health (p<0.001) components of quality of life in diabetic subjects and physical health sub-scale (p=0.004) in all participants.

Conclusion:

Serum 25-hydroxyvitamin D concentration was significantly lower in diabetic subjects in comparison with healthy controls. There was a significant reverse relationship between serum concentrations of 25-hydroxyvitamin D with diastolic blood pressure and on the other hand, a significant positive relationship with physical function, social function and general health components and physical health subscale of quality of life in participants with DM Ⅱ.

Is there an association between serum 25(OH)D3 and mental well-being in patients with type 2 diabetes? Results from a cohort study in primary care

PURPOSE

There are limited and inconsistent results on the correlation between vitamin D and mental health in patients with type 2 diabetes (T2D). Thus, our aim was to explore the association between vitamin D and mental well-being in a community-based sample of participants with T2D.

METHODS

We analyzed serum 25-hydroxyvitamin D₃ (25(OH)D₃) in 698 patients with T2D at the baseline examination. The cohort was reinvestigated after 4 years. Data from SF-36 questionnaires measuring vitality and mental health at baseline and after 4 years were used for analyses.

RESULTS

Serum 25(OH)D₃ was inversely associated with poor mental health at baseline (odds ratio (OR) for 10 nmol/l increase in 25(OH)D₃, 0.90 (95% confidence interval (CI) 0.83-0.96, p = 0.003)) but not at follow-up (p > 0.05). Serum 25(OH)D₃ was not associated with vitality at baseline (p > 0.05). At follow-up, there was an inverse association between 25(OH)D₃ and low vitality (OR for 10 nmol/l increase in 25(OH)D₃, 0.89 (95% CI 0.82-0.97, p = 0.009)) but not after adjustment.

CONCLUSION

We found an inverse association between 25(OH)D₃ and mental health in patients with T2D at baseline. We found no association between 25(OH)D₃ and vitality after adjustment. Future studies are needed to determine the association between vitamin D and mental well-being in patients with T2D.

Focus on 1,25-Dihydroxyvitamin D3 in the Peripheral Nervous System

In this review, we draw attention to the roles of calcitriol (1,25-dihydroxyvitamin D3) in the trophicity of the peripheral nervous system. Calcitriol has long been known to be crucial in phosphocalcium homeostasis. However, recent discoveries concerning its involvement in the immune system, anti-cancer defenses, and central nervous system development suggest a more pleiotropic role than previously thought. Several studies have highlighted the impact of calcitriol deficiency as a promoting factor of various central neurological diseases, such as multiple sclerosis, amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease. Based on these findings and recent publications, a greater role for calcitriol may be envisioned in the peripheral nervous system. Indeed, calcitriol is involved in myelination, axonal homogeneity of peripheral nerves, and neuronal-cell differentiation. This may have useful clinical consequences, as calcitriol supplementation may be a simple means to avoid the onset and/or development of peripheral nervous-system disorders.

Vitamin D deficiency is associated with poorer satisfaction with diabetes-related treatment and quality of life in patients with type 2 diabetes: a cross-sectional study

BACKGROUND

In this cross-sectional study, we assessed the possible association of vitamin D deficiency with self-reported treatment satisfaction and health-related quality of life in patients with type 2 diabetes.

METHODS

We performed a sub-analysis of a previous study and included a total of 292 type 2 diabetic patients. We evaluated treatment satisfaction and health-related quality of life through specific tools: the Diabetes Treatment Satisfaction Questionnaire and the Audit of Diabetes-Dependent Quality of Life. Vitamin D deficiency was defined as 25 (OH) D serum levels < 15 ng/mL.

RESULTS

Multivariable linear regression models were used to estimate the relationship of vitamin D deficiency with both outcomes once adjusted for self-reported patient characteristics. Vitamin D deficiency was significantly associated with the final score of the Diabetes Treatment Satisfaction Questionnaire and the single "diabetes-specific quality of life" dimension of the Audit of Diabetes-Dependent Quality of Life (p = 0.0198 and p = 0.0070, respectively). However, lower concentrations of 25-OH vitamin D were not associated with the overall quality of life score or the perceived frequency of hyperglycaemia and hypoglycaemia.

CONCLUSIONS

Our study shows the association between vitamin D deficiency and both the self-reported diabetes treatment satisfaction and the diabetes-specific quality of life in patients with type 2 diabetes.

Experimental study on 1,25(OH)2 D3 amelioration of oral lichen planus through regulating NF-κB signaling pathway

OBJECTIVE

To explore the protective function of vitamin D (VD)/vitamin D receptor (VDR) on the development of oral lichen planus (OLP) and elaborate the underling mechanism of it.

METHODS

H&E staining, myeloid peroxidase (MPO) assays, quantitative PCR (qPCR), Western blotting, and Elisa were used to test the human biopsies and serum. QPCR, Western blotting, Elisa, and siRNA transfection were also performed in LPS-induced keratinocytes to observe the functions of vitamin D and VDR.

RESULTS

The lack of VDR in the diseased biopsies from OLP patients was associated with activated helper T-cell type 1 (Th1)-driven inflammatory response. Importantly, the status of serum 25-hydroxyvitamin D of OLP patients was reduced consistently. In a cultured cell model, 1,25(OH)₂ D₃ could downregulate excessive production of pro-inflammatory factors induced by lipopolysaccharide (LPS) in keratinocyte HaCat cells. Mechanistically, even though LPS-induced cytokines in keratinocytes were inhibited both by nuclear factor-κB (NF-κB) inhibitor and by activator protein 1 (AP-1) inhibitor, VDR-dependent 1,25(OH)₂ D₃ blocked the activation of phosphorylated-NF-κB p65 rather than c-Jun/c-Fos in the presence of LPS stimulation.

CONCLUSION

These results suggest that 1,25(OH)₂ D₃ plays an anti-inflammatory role in OLP by mediating NF-κB signaling pathway but not AP-1 signaling pathway with a VDR-dependent manner, predicting vitamin D supplement may be a potential strategy for the OLP management.