Bone mineral density, vitamin D status, and calcium intake in healthy female university students from different socioeconomic groups in Turkey

Total, free, and bioavailable 25-hydroxyvitamin D levels in patients with periodontitis (stage III): a case-control study

OBJECTIVE

The aim of this study was to investigate the relationship between total, free and bioavailable 25-hydroxyvitamin D levels, and periodontitis.

MATERIALS AND METHODS

Thirty-nine patients with periodontitis diagnosis and 44 healthy participants were included in this study. 25-Hydroxyvitamin D, vitamin D-binding protein, procalcitonin, and albumin levels were measured from the serum samples obtained. Free and bioavailable 25-hydroxyvitamin D levels were calculated. Total, free, and bioavailable 25-hydroxyvitamin D levels were compared between the healthy control and periodontitis groups. The association of total 25 (OH)D levels with periodontitis was tested through univariate analysis and multivariate logistic regression.

RESULTS

Total 25-hydroxyvitamin D, bioavailable 25-hydroxyvitamin D, and free 25-hydroxyvitamin D levels were significantly lower in the periodontitis group than in the healthy control group (p < 0.001). In the logistic regression analysis, a significant correlation was observed between total 25-hydroxyvitamin D and periodontitis (p<0.001).

CONCLUSION

Our study shows that there is a relationship between total, free and bioavailable 25-hydroxyvitamin D levels and periodontitis. In addition, it has been shown that the determination of free and bioavailable 25-hydroxyvitamin D levels does not provide additional advantages in terms of the relationship between periodontitis and vitamin D.

CLINICAL RELEVANCE

In this case-control study, we examined the relationship between total, free and bioavailable 25-hydroxyvitamin D and periodontitis. We found lower total, free, and bioavailable 25-hydroxyvitamin D levels in periodontitis patients. It was also found that vitamin D-binding protein may be an important biomarker in the identification of various forms of periodontal disease.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT05343273.

BMI, socioeconomic status, and bone mineral density in U.S. adults: Mediation analysis in the NHANES

Introduction

The mechanism by which socioeconomic status (SES) affects bone mineral density (BMD) remains unknown, and body mass index (BMI) may be a potential mediator. The purpose of this study was to investigate whether BMI mediates the relationship between SES [education level and poverty income ratio (PIR)] and lumbar BMD and the proportion it mediates.

Methods

This study included a total of 11,075 adults from the National Health and Nutrition Examination Survey (NHANES). Lumbar BMD was measured at the lumbar spine by dual-energy X-ray absorptiometry (DXA). Multivariate linear regression and smoothing curve fitting were used to investigate the relationship between SES and lumbar BMD. Mediator analysis was used to investigate the proportion of BMI mediating the association between SES and BMD.

Results

In the fully adjusted model, there was a positive correlation between SES and BMD (education level: β = 0.025, 95% CI: 0.005, 0.045; PIR: β = 0.007, 95% CI: 0.002, 0.011). Mediation analysis showed that BMI mediated the relationship between PIR, education level, and lumbar BMD with a range of mediation proportions from 13.33 to 18.20%.

Conclusion

BMI partially mediated the positive association between SES and BMD, and this association may be largely mediated by factors other than BMI.

Biochemical characteristics and calcium and PTH levels of patients with high normal and elevated serum 25(OH)D levels in Turkey: DeVIT-TOX survey

Vitamin D intake over the recommended dose is usually associated with high serum 25(OH)D levels and generally not associated with symptoms of hypercalcemia. High doses of cholecalciferol need to be avoided to protect against vitamin D toxicity and related complications. Strict adherence to the clinical guidelines for treating vitamin D deficiency can ensure safe and effective treatment.

PURPOSE

We observed a tendency to use high doses of cholecalciferol for vitamin D deficiency treatment or vitamin D supplementation. We aimed to determine the biochemical characteristics of patients with high normal and elevated serum 25(OH)D levels.

METHODS

An online invitation was sent to all tertiary endocrinology clinics in Turkey to complete an online retrospective survey (DeVIT-TOX Survey) for patients diagnosed with high serum 25(OH)D levels (> 88 ng/mL) between January 2019 and December 2019. The patients were evaluated according to the presence of signs and symptoms of hypercalcemia and doses of vitamin D intake, evaluated into the following three groups according to their 25(OH)D levels: group 1, > 150 ng/mL; group 2, 149-100 ng/mL; and group 3, 99-88 ng/mL.

RESULTS

A total of 253 patients were included in the final analysis (female/male: 215/38; mean age, 51.5 ± 15.6 years). The average serum 25(OH)D level was 119.9 ± 33 (range, 88-455) ng/mL, and the average serum calcium level was 9.8 ± 0.7 (range, 8.1-13.1) mg/dL. Most (n = 201; 75.4%) patients were asymptomatic despite having high serum 25(OH)D and calcium levels. The serum 25(OH)D level was significantly higher in the symptomatic groups than in the asymptomatic groups (138.6 ± 64 ng/mL vs. 117.7 ± 31 ng/mL, p < 0.05). The most common cause (73.5%) associated with high serum 25(OH)D levels was the inappropriate prescription of a high dose of oral vitamin D (600.000-1.500.000 IU) for treating vitamin D deficiency/insufficiency in a short time (1-3 months). The cut-off value of 25 (OH) D level in patients with hypercalcemia was found to be 89 ng/mL [median 116.5 (89-216)].

CONCLUSIONS

High dose of vitamin D intake is associated with a high serum 25 OH D level, without symptoms of hypercalcemia. Inappropriate prescription of vitamin D is the primary cause for elevated 25(OH) D levels and related hypercalcemia. Hypercalcemia may not be observed in every patient at very high 25(OH) D levels. Adherence to the recommendation of guidelines is essential to ensure safe and effective treatment of vitamin D deficiency.