Resurgence of vitamin D: Old wine in new bottle

Effects of different vitamin D supplementation strategies in reversing metabolic syndrome and its component risk factors in adolescents

There is little evidence on the efficacy of various vitamin D supplementation strategies in reversing metabolic syndrome (MetS) in adolescents. The present study aims to fill this gap. A total of 535 (243/292) out of 650 apparently healthy Saudi adolescents were randomly selected from the Vitamin D School Project database which has baseline and post-intervention information of more than 1000 Saudi adolescents 12-18 years old attending 34 schools in Riyadh, Saudi Arabia from Nov 2014-May 2015. Allocation of intervention was done in 3 groups using cluster randomization: vitamin D tablet, 1000IU/day (N = 180; 69 boys, 111 girls); vitamin D fortified milk consumption, 200 ml/day, 40IU/100 ml (N = 189; 93 boys, 96 girls) and control (educational awareness) (N = 166; 81 boys, 85 girls). All groups were given educational awareness on how to increase vitamin D levels. All groups were matched for BMI and analysis adjusted for age. Post-intervention and using intent-to-treat approach, within-group analysis revealed a statistically significant increase in 25(OH)D levels in all groups, and a clinically significant increase in favor of the tablet group (between-group) [10.7 nmol/l (34.7%) versus 6.3 nmol/l (19.8%) in milk and 2.1 nmol/l (7.0%) in control; p < 0.001], adjusted for age and BMI-matched. Between group analysis also revealed a clinically significant decrease in triglycerides (p = 0.05), glucose (p < 0.001) and systolic blood pressure (p = 0.005) as well as a clinically significant increase in HDL-cholesterol (p = 0.004) over time, all in favor of the tablet group. Within-group comparison showed a significant decrease in the incidence of MetS in the tablet group (9.4% versus 4.4%; p < 0.05) only. In conclusion, oral vitamin D supplementation is superior to vitamin D fortified milk in improving vitamin D status. Reduction in the incidence of MetS in the Arab adolescent population secondary to vitamin D correction may be dose-dependent.

The Role of Vitamin D in Pediatric Orthopedics

Understanding the role of vitamin D is an important component of the proper care of the pediatric orthopedic patient. Vitamin D is an essential component of bone metabolism in the growth and development of the pediatric skeleton, which can be acutely affected by changes to the body's vitamin D, calcium, and phosphate levels, resulting in pathologic conditions such as rickets or fractures. This article reviews the main areas in which vitamin D relates to pediatric orthopedics and highlights some of the areas where future research is being directed.

Does vitamin D deficiency influence the incidence and progression of knee osteoarthritis? - A literature review

OBJECTIVES

Vitamin D has been believed to have a bearing in the pathogenesis of knee osteoarthritis (OA). This study was done to search the literature and review the correlation between vitamin D levels in knee OA in the adult population and the outcome of vitamin D supplementation in knee OA.

METHODS

An exhaustive search of Pub Med and Cochrane library database was done with keywords vitamin D, knee and osteoarthritis for a period from Jan 2005 to December 2015. All Randomized Control Trials (RCT), Cohort, Case-control, cross-sectional studies were included in the present systematic review.

RESULTS

The search resulted in a total of 86 studies; out of which 11 studies were included in the current review. There were two Randomized Control Trial (RCT), one case-control, four cross-sectional and four cohort studies. These studies comprised of a total of 5137 participants (ranging from 46 to 1248) Our results suggested there was a moderate evidence of positive association in vitamin D deficiency (VDD) and progression of radiographic OA (ROA), as assessed by Kellgren and Lawrence (KL) grading. However, VDD was not associated with the incidence of ROA and MRI-detected change in focal cartilage defect. However, this study has a limited evidence for a positive correlation in VDD and the cartilage volume loss. There was also limited evidence showing no role of vitamin D therapy in reducing cartilage volume loss and knee pain in Knee OA.

CONCLUSION

The VDD is common and has been associated with knee OA, in an adult population. However, there is still inconsistent evidence regarding the prevention of incidence and progression of ROA after vitamin D therapy. There is a need for multicentric and well-conducted randomized studies with larger samples to conclude the positive effect of Vitamin D therapy.

Use of Vitamin D Supplements in Osteoarthritis: An Observational Study in a Tertiary Health Care Facility

OBJECTIVE

The purpose of the study was to assess impact of vitamin D supplements on the disease progression and overall health of osteoarthritis (OA) patients.

METHODOLOGY

A cohort study was carried out for 8 months (August 2017-March 2018) in the Orthopedics Department of Kasturba Hospital, Manipal, India, a tertiary care hospital. One hundred and forty-two patients who were diagnosed with OA (grades 1-3) with low serum 25(OH)D levels (severely deficient, deficient, or insufficient) were selected for the study. These patients were categorized into two cohorts: a control cohort (CC) and a study cohort (SC). CC members were patients (n = 71) who had not received vitamin D supplements, and SC members were patients (n = 71) who had received vitamin D supplements. Severity grading of OA, pain score, and health assessment were performed using the Kellgren-Laurence grading score, visual analogue scale (VAS), and WOMAC, respectively, at baseline and after 3 months of follow-up.

RESULTS

Subjects in the both CC and SC reported no statistically significant difference (similar in both group) in severity grade (p = 0.303), pain score (p = 0.099), parathyroid hormone (PTH) (p = 0.083), and health status (p = 0.76) at baseline. After 3 months of follow-up (post vitamin D supplementation), OA patients have shown statistically significant difference in severity grades, serum 25(OH)D status, PTH level (p < 0.001), and overall health status (p = 0.001) in the SC with respect to baseline. Likewise, percentage distribution of positive changes was significantly higher in severity grade, pain score, serum 25(OH)D level, overall health status (p < 0.001), and PTH (p = 0.040) of SC as compared to CC at follow-up.

CONCLUSION

Vitamin D supplements have significantly improved serum 25(OH)D levels, PTH, severity grade, and pain score of OA patients. Most importantly, vitamin D supplements have shown improvement in the overall health of OA patients, emphasizing the place of vitamin D supplements in the management of OA. Clinical Trial Registry-India (CTRI) registration no: CTRI/2017/12/011031.

Effect of modulating dietary vitamin D on the general bone health of rats during posterolateral spinal fusion

Vitamin D plays a significant role in musculoskeletal health by regulating calcium, phosphate, and promoting new bone mineralization. The purpose of this study was to understand the effect of dietary vitamin D on general bone health during peri-operative bone healing via an in vivo dosing study of vitamin D in a rat posterolateral fusion model using autograft. Vitamin D Deficient (DD), vitamin D Insufficient (ID), Control vitamin D (CD), and Hyper-vitamin D (HD) groups were studied. Increasing dietary vitamin D improved quantitative measures of femoral geometry, including femoral strength, stiffness, and density. Femoral biomechanics, cortical thickness, moment of inertia, cross-sectional area, and measures from bone ashing were all greater in the HD group versus the CD. This suggests that additional dietary vitamin D above normal levels during spinal fusion may lead to improvement in bone health. Serum vitamin D levels were also observed to decrease during fusion healing. These results demonstrate that dietary vitamin D improves general bone health in the femur of a rat model during posterolateral spinal fusion. This suggests a role for further clinical evaluation of vitamin D dietary intake during the peri-operative period, with the possibility of avoiding adverse consequences to general bone health. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1435-1443, 2018.

Vitamin D deficiency and biochemical variations among urban Saudi adolescent girls according to season

Objectives:

To determine seasonal variations in the vitamin D status of Saudi adolescent girls in Riyadh, Kingdom of Saudi Arabia (KSA) and its effect in biochemical and clinical characteristics.

Methods:

In this prospective study, a total of 2000 Saudi females aged 12-18 years from different schools in Riyadh, KSA participated and submitted a generalized questionnaire with clinical information. Fasting blood samples were obtained in 1618 subjects for the winter season (December to February) and only 499 subjects returned to submit fasting blood samples for the summer season (June-August). Circulating serum 25(OH)D, parathyroid hormone (PTH), and other biomarkers of bone remodeling were measured during both seasons.

Results:

Vitamin D deficiency (serum 25(OH)D <25 nmol/L) was significantly higher during summer than winter (63.5% versus 40.8%; p<0.001). Mean serum PTH was also significantly higher during summer than winter (p<0.01). In all subjects, serum PTH showed a significant inverse association with 25(OH)D at levels below 40 nmol/L (r=-0.21; p<0.001). The prevalence of subjects having clinical and metabolic manifestations suggestive of osteomalacia was 2.1% (N=33 out of 1548).

Conclusion:

Seasonal variations in the vitamin D status of Saudi adolescent females significantly modifies biochemical parameters as response to vitamin D status change. In the meantime, heightened public health awareness should be given to populations at higher risk for vitamin D deficiency.

Serum 25-hydroxyvitamin D and bone turnover markers in Palestinian postmenopausal osteoporosis and normal women

This study evaluated the association of vitamin D and bone markers with the development osteoporosis in Palestinian postmenopausal women. Even though vitamin D deficiency was very high for the recruited subjects, it was not associated with osteoporosis except for bones of the hip. Age and obesity were the strongest determining factors of the disease.

PURPOSE

The purpose of this study was to investigate the association of bone mineral density (BMD) with serum vitamin D levels, parathyroid hormone (PTH), calcium, obesity, and bone turnover markers in Palestinian postmenopausal women.

METHODS

Three hundred eighty-two postmenopausal women (≥45 years) were recruited from various women clinics for BMD assessment (131 women had osteoporosis and 251 were normal and served as controls). Blood samples were obtained for serum calcium, PTH, 25(OH)D, bone formation (N-terminal propeptide (PINP)), and bone resorption (serum C-terminal telopeptide of type I collagen (CTX1)) markers.

RESULTS

Women with osteoporosis had statistically significant lower mean weight, height, body mass index (BMI), and serum calcium (p < 0.05) compared to controls. No significant differences were detected between the mean values of bone turnover markers (CTX and PINP), 25(OH)D, and PTH of the two groups. Women with vitamin D deficiency (severe and insufficiency) represented 85.9% of the study subjects. Multiple and logistic regression showed that age and BMI significantly affected BMD and vitamin D had a significant association with BMD only at the lumbar spine. BMI was positively correlated with BMD and PTH but negatively correlated with vitamin D. Logistic regression showed that the odds ratio (OR) for having osteoporosis decreased with increasing BMI (overweight OR = 0.11, p = 0.053; obese OR = 0.05, p = 0.007).

CONCLUSIONS

There was no direct correlation between BMD and PTH, bone turnover markers, and vitamin D except at the lumbar spine. A negative correlation between BMD and age and a positive correlation with BMI were observed. The protective effect of obesity on osteoporosis was complicated by the effect of obesity on vitamin D and PTH.

High prevalence of hypovitaminosis D of patients with autoimmune rheumatic diseases in China

We aimed to determine the prevalence of hypovitaminosis D in patients with autoimmune rheumatic diseases (ARDs) in China and its association with demographic characteristics of the patients. We recruited 384 patients in this cross-sectional study including 121 cases of systemic lupus erythematosus (SLE), 131 rheumatoid arthritis (RA), 102 spondyloarthritis (SpA) and 30 other ARDs. For each patient, demographic information was collected and serum concentration of 25OHD3 was measured by electrochemiluminescence immunoassay (ECLIA). The multivariate logistic regression model was used to investigate the association between vitamin D deficiency and patient characteristics. The mean serum vitamin D level of the 384 patients was 18.91 (8.12) ng/mL, and the median age was 37.33 (12.01) yrs. Among these patients, 222 (57.81%) and 127 (33.07%) were found to be vitamin D deficiency and insufficiency, respectively. From the disease perspective, the percentages of insufficiency and deficiency were as follow: 97.52% and 84.30% in SLE, 87.02% and 48.85% in RA, 88.24% and 40.20% in SpA, 90.89% and 57.81% in other ARDs patients. The causative factors for vitamin D deficiency included SLE per se (OR 12.54, P < 0.001) and high body mass index (BMI) (OR 1.88, P < 0.001). However, the seniors were less likely to have vitamin D deficiency (OR 0.95, P = 0.005). No correlation was disclosed between vitamin D deficiency and gender or disease duration. Hypovitaminosis D is highly prevalent among autoimmune rheumatic diseases population in China. The SLE per se and the obesity are the risk factors for vitamin D deficiency. Clinicians are advised to supplement vitamin D in these patients.