Vitamin D Levels of Out-Patients in Lithuania: Deficiency and Hypervitaminosis

Pre-existing osteoporosis and serum vitamin D levels in patients with distal radius fractures: are we missing something?

INTRODUCTION

Given the significant therapeutic gap for osteoporosis, this study aims to investigate the most common osteoporosis-related fracture. The analysis will also consider patients' serum vitamin D levels and the indications for basic osteoporosis diagnostic tests and osteoporosis therapy prior to fracture.

MATERIALS AND METHODS

This prospective clinical trial included patients with distal radius fractures who underwent surgery at our hospital between 1 April 2021 and 7 April 2022. Blood samples were taken from all participants and existing risk factors for osteoporosis were recorded. In addition, the indication for a guideline-based osteoporosis diagnosis was assessed and the risk of another future fracture with FRAX® was calculated. This information was used to decide whether there was an indication for specific osteoporosis therapy.

RESULTS

A diagnosis gap of 53% and a treatment gap of 84% were identified among the 102 patients investigated. The patients' ages ranged from 46 to 91 years, with an average vitamin D level of 57 nmol/l, which was below the recommended level of 75 nmol/l. It was noted on a monthly basis that the vitamin D level (without substitution) never exceeded the recommended value of 75 nmol/l in any month. Three-quarters of patients had indications for a baseline osteoporosis diagnosis, yet less than 50% received one. According to FRAX® data, 57% of patients had indications for specific osteoporosis treatment before experiencing the fracture.

CONCLUSION

Even without a previous distal radius fracture, many patients are in need of osteoporosis diagnosis or treatment. Our research suggests that patients with distal radius fractures should have their vitamin D levels checked via a blood test and be evaluated for osteoporosis. As endogenous vitamin D levels are often inadequate, year-round vitamin D supplementation should be considered for the prevention of osteomalacia and as a basis for the treatment of osteoporosis.

GERMAN CLINICAL TRIAL REGISTER ID

DRKS00028085.

Difference in Levels of Vitamin D between Indoor and Outdoor Athletes: A Systematic Review and Meta-Analysis

Vitamin D, its importance in different processes taking place in the human body, the effects of abnormal levels of this hormone, either too low or too high, and the need for supplementation have been extensively researched thus far. Variances in exposure to sunlight can cause vitamin D levels to fluctuate. Indoor activity can be a factor for these fluctuations and can lead to a decrease in vitamin D levels. We conducted a systematic review and meta-analysis aiming to identify whether indoor compared to outdoor training has a significant influence on vitamin D levels; we also performed subgroup analyses and multivariate meta-regression. The type of training has an impact on vitamin D levels that is influenced by multiple cofounders. In a subgroup analysis not considering cofounders, the mean serum vitamin D was 3.73 ng/mL higher in outdoor athletes, a difference which barely fails to achieve significance (p = 0.052, a total sample size of 5150). The indoor-outdoor difference is only significant (clinically and statistically) when considering studies performed exclusively on Asian athletes (a mean difference of 9.85 ng/mL, p < 0.01, and a total sample size of 303). When performing the analyses within each season, no significant differences are observed between indoor and outdoor athletes. To control for multiple cofounders (the season, latitude, and Asian/Caucasian race) simultaneously, we constructed a multivariate meta-regression model, which estimated a serum vitamin D concentration lower by 4.446 ng/mL in indoor athletes. While a multivariate model suggests that outdoor training is associated with slightly higher vitamin D concentrations when controlling for the season, latitude, and Asian/Caucasian race, the type of training has a numerically and clinically small impact. This suggests that vitamin D levels and the need for supplementation should not be decided based on training type alone.

Serum Vitamin D Levels Explored in the Latvian Cohort of Patients with Basal Cell Carcinoma Linked to the Sonic Hedgehog and Vitamin D Binding Protein Cutaneous Tissue Indices

Ultraviolet radiation is known as one of the major contributors to skin malignancies, including basal cell carcinoma (BCC), which is the most common type of skin cancer. It is a heterogeneous tumor, which presents with various types that are stratified into low- and high-risk tumors. Sunlight is important for overall health and vitamin D synthesis in the skin, whereas deviations from the optimal level of vitamin D are shown to be associated with the risk of the development of BCC. The accumulating evidence suggests the ability of vitamin D to antagonize the Sonic Hedgehog (SHH) signaling, the key tumor pathway, and play a protective role in the development of BCC. Additionally, a vitamin D binding protein (DBP) is shown to be implicated in the complex regulation of vitamin D. Here, we aimed to explore serum vitamin D in patients with different primary and recurrent BCC of the head and neck and investigate cutaneous DBP and SHH indices, confirmed immunohistochemically in these subjects. According to the results, 94.9% of the Latvian cohort of BCC patients were found to be deficient in vitamin D. No significant differences in serum vitamin D levels were found between genders, primary and recurrent tumors, and different types of BCC. Serum vitamin D was inversely associated with tumor size. Susceptible male individuals with low blood vitamin D levels were recognized at risk of developing aggressive and recurrent BCC confirmed by the use of hierarchical clustering analysis. In smaller tumors with a favorable course, such as superficial and nodular BCC, the association between high DBP and low SHH tissue expression was found, providing supportive evidence of the existence of a link between vitamin D, proteins involved in its metabolism, as exemplified by the DBP and SHH signaling pathway. The assumption of a deficiency in the protective effect of vitamin D in patients with high-risk BCCs was proposed in low DBP and high SHH tissue indices. New extensions to existing knowledge and characterization of the BCC signaling pathways and their cross-talk with vitamin D are warranted when searching for a preferential effect of vitamin D on skin cancer.

Seasonal variation in calcium treatment after thyroidectomy as surrogate for post-operative hypocalcemia: a retrospective register-based national cohort study

Background

Hypocalcemia is one of the most common complications of thyroidectomy, and vitamin D deficiency has been found to be an independent risk factor. Sweden is located north of the 55th latitude, resulting in a significant seasonal variation in sun exposure, thereby large variation in the naturally occurring levels of vitamin D. This study aimed to determine if there is a correlation between season of surgery and post-thyroidectomy hypocalcemia.

Methods

We conducted a retrospective register-based observation study on patients who had undergone total thyroidectomy during 2008–2015. In total, 7125 patients operated in Swedish facilities were identified via the Scandinavian Quality Register for Thyroid, Parathyroid, and Adrenal Surgery (SQRTPA). Patients operated during February–April were included in the dark group and patients operated during August–October were included in the bright group. Further stratification was made on the indication for surgery. The primary outcome was post-operative calcium treatment due to hypocalcemia, defined as having received calcium orally or intravenously before discharge.

Results

The risk of receiving post-operative calcium treatment was significantly lower in the bright group (29.7%) compared to the dark group (35.1%), with a relative risk of 0.846 (P < 0.001). This correlation held true if the indication for surgery was goiter or thyrotoxicosis. For malignancy, there was no significant difference between the groups.

Conclusion

In this cohort, total thyroidectomy performed during August–October was associated with a lower rate of calcium treatment given post-operatively when compared to total thyroidectomy performed during February–April. This would indicate a decreased risk of post-operative hypocalcemia if surgery was carried out after the brighter season.

Seasonal variation of serum 25-hydroxyvitamin D level in hemodialysis patients in the northernmost island of Japan

BACKGROUND

Serum vitamin D level shows a seasonal variation, being lower in winter than in summer in healthy subjects. The aim of this study was to determine whether there is presence of such a seasonal variation in hemodialysis patients.

METHODS

A total of 102 patients on hemodialysis were enrolled in February 2017 (winter) for analyses of serum levels of 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)₂D] and treatments for chronic kidney disease-mineral and bone disorder (CKD-MBD). The examinations were repeated in August 2017 (summer). After exclusion of patients with malignancy, loss of follow-up and missing data, 78 patients contributed to the analyses.

RESULTS

Serum level of 25(OH)D, but not that of 1,25(OH)₂D, was significantly lower in winter (14.0 ng/mL) than in summer (15.5 ng/mL), though there was no significant difference in regimen for CKD-MBD treatment including vitamin D receptor activators (VDRAs) between the two seasons. Serum intact parathyroid hormone level tended to be higher and alkaline phosphatase was significantly higher in winter than in summer. Linear mixed-effects model analysis showed that level of 25(OH)D, but not that of 1,25(OH)₂D, was significantly associated with season (winter and summer) after adjustment of age, sex, dialysis vintage, albumin level and use of drugs for CKD-MBD.

CONCLUSION

Serum 25(OH)D has a seasonal variation, being lower in winter than in summer, independent of CKD-MBD treatment including treatment with VDRAs in Japanese hemodialysis patients. The impact of the seasonal variation on risk of vitamin D deficiency and its effect on prognosis remain to be investigated.

Nutrihealth Study: Seasonal Variation in Vitamin D Status Among the Slovenian Adult and Elderly Population

Several studies conducted around the world showed substantial vitamin D insufficiency and deficiency among different population groups. Sources of vitamin D in the human body include ultraviolet B (UVB)-light-induced biosynthesis and dietary intake, but people's diets are often poor in vitamin D. Furthermore, in many regions, sun exposure and the intensity of UVB irradiation during wintertime are not sufficient for vitamin D biosynthesis. In Slovenia, epidemiological data about vitamin D status in the population were investigated through a national Nutrihealth study-an extension to the national dietary survey SI.Menu (2017/18). The study was conducted on a representative sample of 125 adult (18-64 years) and 155 elderly (65-74 years old) subjects, enrolled in the study in different seasons. Their vitamin D status was determined by measuring the serum 25-hydroxy-vitamin D (25(OH)D) concentration. Thresholds for vitamin D deficiency and insufficiency were 25(OH)D levels below 30 and 50 nmol/L, respectively. Altogether, 24.9% of the adults and 23.5% of the elderly were found to be vitamin D deficient, while an insufficient status was found in 58.2% and 62.9%, respectively. A particularly concerning situation was observed during extended wintertime (November-April); vitamin D deficiency was found in 40.8% and 34.6%, and insufficient serum 25(OH)D levels were observed in 81.6% and 78.8%, respectively. The results of the study showed high seasonal variation in serum 25(OH)D levels in both the adult and elderly population, with deficiency being especially pronounced during wintertime. The prevalence of this deficiency in Slovenia is among the highest in Europe and poses a possible public health risk that needs to be addressed with appropriate recommendations and/or policy interventions.

The one-year mortality rate in elderly patients with osteoporotic fractures of the pelvis

Osteoporosis is a common condition for elderly people. The incidence of osteoporotic pelvic fractures has been increasing. Osteoporotic pelvic fractures are associated with increased mortality rates. Based on the aim of our study, we found out that one-year mortality rate after a pelvic fracture is high and depends on the fracture type.

PURPOSE

The aim of this study was to determine the one-year mortality rate in patients aged 65+ with osteoporotic pelvic fractures depending on the type of fracture according to AO/OTA classification.

METHODS

Patients aged 65+ with pelvic insufficiency fractures admitted to a single center between 1 June 2013 and 31 December 2016 were enrolled in the study. The fractures were classified according to AO/OTA classification. The start of the survival time analysis was the date of the injury. The end of the analysis was 31 December 2017 or the date of the patient's death. Mortality rates were assessed with respect to fracture types using Kaplan-Meier curves. The Cox proportional hazards model was applied to assess the dependence of mortality on the fracture type.

RESULTS

A total of 105 patients with 95 (90.5%) being female were enrolled in this prospective study. The average age was 80.3 years (95% CI 78.8-81.7). Mean follow-up time was 23.5 months (95% CI 20.7-26.4). According to AO/OTA classification, 30 (28.6%) patients had a type A pelvic fracture, 73 (69.5%) patients-type B fracture, and 2 (1.9%)-type C fracture. Overall, the one-year mortality rate was 23.8% (95% CI 16.8-33.2%). For patients with type A fracture, the one-year mortality rate was 13.3% (95% CI 5.2-31.7%) compared with 27.4% (95% CI 18.6-39.2%) in the group with type B fracture, and this difference was statistically significant (p < 0.001).

CONCLUSIONS

We found that within a year after an osteoporotic pelvic fracture, the number of deaths in the patients having type B pelvic fracture was twice higher than in the patients with type A fracture.