Contribution of sun exposure to the vitamin D dose received by various groups of the Spanish population

Impact of COVID-19 Pandemic and Associated Restrictions on Vitamin D Status in a Large Cohort of Italian Children and Adolescents

Background and Objectives: Vitamin D is synthesized in the skin upon sunlight exposure, showing variations with season and latitude. We aimed to investigate the influence of age, sex, and season on vitamin D status in a large pediatric cohort during the COVID-19 pandemic period and the corresponding pre-pandemic period. Materials and Methods: Retrospective data concerning subjects aged < 18 years were extracted anonymously from the large database of a reference laboratory hospital (Sassari, Northern Sardinia, Italy). Serum 25-hydroxyvitamin D [25(OH)D] levels measured during the pre-pandemic period (1 March 2018 to 30 September 2019) were compared with those detected during the pandemic period (1 March 2020 to 30 September 2021). Results: A total of 2317 samples from subjects aged < 18 years were included in the analysis, 1303 (47.9% females) of which were collected in the pre-pandemic period and 1014 (51.3% females) in the pandemic period. No significant differences in 25(OH)D levels were found between the two periods, whereas, in children aged < 2 years, levels were higher than those in children aged 11-16 years (p < 0.05). Monthly levels of 25(OH)D between pre-pandemic and pandemic periods did not differ, although significant differences were detected across months (p < 0.0001). Similarly, 25(OH)D values did not differ significantly between males and females in both periods. Marked seasonal variations were observed in males and females across all age groups. Conclusions: Serum vitamin D levels and their season-related variations were not significantly affected by the COVID-19 pandemic and associated restrictions in a large cohort of Italian children and adolescents.

Development and Validation of Vitamin D- Food Frequency Questionnaire for Moroccan Women of Reproductive Age: Use of the Sun Exposure Score and the Method of Triad's Model

This cross-sectional study aimed to develop and validate a vitamin D food frequency questionnaire (VitD-FFQ) to assess vitamin D intake in Moroccan women of reproductive age. Using the method of triads, the VitD-FFQ was validated against seven-day dietary records (7d-FR) and 25-hydroxyvitamin D (25(OH)D) as a biomarker of vitamin D status in 152 women (aged 18-45 years). Participants' sun exposure scores (SES) were assessed using a specific questionnaire (SEQ). Predictors of vitamin D status were identified via linear regression models. Several statistical tests were applied to evaluate the criterion validity of the FFQ against two references methods (7d-FR and the biomarker-serum 25(OH)D). Median (Interquartile range) intakes were 7.10 ± 6.95 µg /day and 6.33 ± 5.02 µg/ day, respectively, for VitD-FFQ and 7d-FR. Vitamin D status was mainly determined by SES (R = 0.47) and vitamin D absolute food intakes derived by the VitD-FFQ (R = 0.56), which demonstrated a more significant prediction ability compared to 7d-FR (R = 0.36). An agreement was observed between the VitD-FFQ and 7d-FR (BA index of 3.29%) with no proportional bias (R² = 0.002, p = 0.54). <10% of participants were incorrectly classified, and weighted kappa statistics showed that VitD-FFQ had an acceptable ranking ability compared to the 7d-FR and the biomarker. The validity coefficient for the VitD-FFQ was high: ρQR = 0.90 (95%CI: 0.89-0.92), and a range from 0.46 to 0.90. Adjustment for the participants' SES and BMI (body mass index) improved the biomarker's validity coefficient (ρRB 0.63 (95% CI 0.39-0.82). Our results indicate that the VitD-FFQ is valid for estimating absolute vitamin D intake in Moroccan women of reproductive age.

Oral health and vitamin D in adult: a systematic review

This systematic review aimed to provide a synthesis of the evidence relating to how the provision of vitamin D supplements influences oral health status. An electronic database search was performed across six databases using a standardised search strategy. The PICO framework (Population, Intervention, Comparison, Outcome) was used to define the review question. The screening and selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses process (PRISMA). The quality of reporting was assessed using Consolidated Standards of Reporting Trials (CONSORT) guidelines, and the bias was assessed using the revised Cochrane tool RoB2. A total of 1812 studies were retrieved. 1427 studies were excluded due to unmet inclusion criteria. Full texts of seventy-five potential studies were retrieved and ultimately six studies met the inclusion criteria. There were limitations in the quality of reporting of studies (between 49 % and 73 %). 70 % of the risk of bias items were in the low risks category. Vitamin D interventions varied with respect to dosage and duration. Qualitative syntheses identified significantly better oral health outcomes. Heterogeneity of study design, intervention and outcomes precluded quantitative synthesis. Few clinical trials investigated the effect of vitamin D supplementation on oral health. There is considerable heterogeneity among studies interventions and oral health outcomes. Quality of reporting of studies has limitations and there is evidence of study biases. Nonetheless, qualitative synthesis of the evidence suggests that vitamin D supplements improve oral health outcomes, particularly periodontal health. Calcium may also play a significant role. Further high-quality trials are required of comparable vitamin D supplements with similar oral health outcomes focused to inform quantitative synthesis of the evidence.

Serum 25-Hidroksi D Vitamini ve Kalsiyum Seviyeleri ile İdiyopatik Benign Paroksismal Pozisyonel Vertigo Arasındaki İlişki

Amaç: Kliniğimize baş dönmesi şikâyeti ile başvurup idiopathic benign paroksismal pozisyonel vertigo (BPPV) tanısı alan hastalar ile baş dönmesi olmayan sağlıklı kontrol grubunun 25-hidroksi vitamin D (25-OH vitamin D) ve Ca2+ düzeylerinin karşılaştırılması Ca2+ ve 25-OH vitamin D’nin BPPV gelişimindeki rolünün araştırılmasıdır. Gereç ve Yöntem: Çalışmamız geriye dönük vaka kontrol çalışması olup, 01.01.2018-01.08.2021 arası Alanya Egitim ve Araştırma Hastanesi Nöroloji polikliniğine başvuran İdiopatik BPPV tanısı alan 409 hasta ile kontrol grubu olarak kliniğimize başvuru öncesi son 1 yıl içerisinde vertigo, dizziness ya da dengesizlik nedeniyle hekim başvurusu olmayan serum D vitamini düzeyi ölçümü yapılmış 338 hasta seçilerek oluşturuldu. İstatiksel değerlendirmeler için ki-kare ve T testi testi kullanıldı. Bulgular: Ortalama serum 25-OH vitamin D düzeyleri BPPV ve kontrol grubunda sırasıyla 15,74 ng/mL ve 17,91 ng/mL idi. Serum 25-OH vitamin D düzeyleri BPPV grubunda kontrol grubuna göre anlamlı derecede düşük bulundu ((p=0,01, p

1,25-dihydroxyvitamin D and cardiometabolic risk in healthy sedentary adults: The FIT-AGEING study

BACKGROUND

A growing body of scientific works investigating the physio-pathological mechanisms behind cardiovascular disease has suggested that vitamin D deficiency could play a key role on its development. However, it remains unclear whether its active form (1,25-dihydroxyvitamin D [1,25(OH)₂D] is associated with cardiometabolic risk factors in healthy individuals. The aim of the present study was to investigate the relationships of 1,25(OH)₂D plasma levels with cardiometabolic risk factors in a sample of healthy sedentary adults.

METHODS

A total of 73 adults (~53% women; 54 ± 5 years old) were included in the current cross-sectional study. A sex-specific cardiometabolic risk score (MetScore) was calculated for each subject based on clinical parameters (i.e., waist circumference, systolic and diastolic blood pressure, plasma glucose, high-density lipoprotein cholesterol, and triglycerides) according to the International Diabetes Federation's clinical criteria. Plasma levels of 1,25(OH)₂D were measured using a DiaSorin Liaison® immunochemiluminometric analyzer.

RESULTS

No significant association was detected between 1,25(OH)₂D and MetScore (β = 0.037, R² = 0.001, p = 0.77), independently of age, sex and fat body mass index. A significant inverse association were observed between 1,25(OH)₂D and waist circumference (β = -0,303, R² = 0.092, p = 0.01). These results were consistent after controlling by potential confounders.

CONCLUSION

In summary, the present results suggest that 1,25(OH)₂D plasma levels are not associated with either cardiometabolic risk factors or insulin resistance in healthy sedentary adults. However, an inverse association of 1,25(OH)₂D plasma levels with central adiposity was observed in our study sample.

National and subnational burden of disease attributable to occupational exposure to solar ultraviolet radiation (SUVR) in Iran, 2005-2019

Overexposure to solar ultraviolet radiation (SUVR) can cause skin and eye adverse effects for outdoor workers. In this study, the burden of disease induced by occupational exposure to SUVR and its spatiotemporal trend at national and sub-national levels in Iran, 2005-2019 were assessed. The attributable burden of disease was assessed using the following five datasets: (1) distribution of occupational exposure to SUVR, (2) total incidences and deaths of health outcomes of SUVR exposure, (3) population attributable fractions of the health outcomes of SUVR exposure, (4) age-gender distribution of outdoor workers, and (5) disability-adjusted life year (DALY) calculation constants. During 2005-2019, the attributable DALYs increased from 2442 to 2907 and the attributable DALY rate (per 100,000 workers) slightly decreased from 11.94 to 11.91. The share of YLL in the attributable burden of disease was in the range of 43%-46%. Out of nine causes, about 90% of the attributable burden of disease in 2019 was related to cataracts (29.9%), malignant skin melanoma (27.4%), squamous-cell carcinoma (18.6%), and sunburn (17.2%). During the study period, the attributable DALY rate in women increased by 60.95% (from 5.04 to 8.11) and in men decreased by 2.06% (from 13.03 to 12.76). The total attributable DALYs and DALY rate rose by age during 2005-2019. The contributions of population growth, risk-deleted DALY rates, exposure risk, and population age structure in temporal changes of the attributable burden of disease were 19.27%, 9.13%, -1.35%, and -14.8%, respectively. The three highest attributable DALY rates in 2019 were observed in South Khorasan (21.28), Chahar Mahal and Bakhtiari (17.42), and Kordestan (17.26), respectively. The preventive interventions against SUVR overexposure, regular screenings, and early treatments with an emphasis on occupations with continuous sun exposure and provinces with increasing attributable DALY rates should be considered in the occupational health action plan in the country.

Spatiotemporal analysis of solar ultraviolet radiation based on Ozone Monitoring Instrument dataset in Iran, 2005-2019

The solar ultraviolet radiation (UVR) at national, provincial and county levels in Iran during 2005-2019 were determined based on Ozone Monitoring Instrument (OMI) dataset. The temporal (annual and monthly) trends and spatial distributions of the UVR in terms of erythemally weighted daily dose (EDD), erythemally weighted irradiance at local solar noon time (EDR), and UV index and the major factors influencing the spatiotemporal trends were analyzed. The population-weighted average values of EDD, EDR, and UV index in Iran were respectively 3631 J/m², 176.3 mW/m², 7.1 in 2005 and rose by 0.22% per year to 3744 J/m², 181.7 mW/m², and 7.3, respectively in 2019, but the annual trend was not statistically significant. The EDD in Iran during the study period exhibited the highest monthly average value in June (6339 J/m²) and the lowest one in December (1263 J/m²). The solar UVA/UVB ratios at the national level during 2005-2019 were considerably lower in summer. The EDD provincial average values in the study period were in the range of 2717 (Gilan) to 4424 J/m² (Fars). The spatiotemporal variations of the solar UVR parameters were well described by the linear models as a function of cloud optical thickness (COT), ozone column amount, surface albedo, latitude, and altitude (R² > 0.961, p value < 0.001) and the temporal changes of the solar UVR parameters were mainly caused by the COT. The results indicated that non-burning exposure to solar UVR in summer can be more efficient for vitamin D synthesis due to higher contribution of UVB in the solar UVR. The spatial distributions and temporal trends should be considered to determine the optimal duration, time and condition of exposure to the solar UVR for the public and occupational training and public health measures.

Association of serum 25-Hydroxyvitamin D with Vitamin D intervention and outdoor activity among children in North China: an observational study

Background

Living at high latitudes is one of the risk factors for vitamin D deficiency in children. However, evidence on vitamin D improvement for this pediatric population to date is limited. This study aims at evaluating the association of different vitamin D intervention methods and outdoor activity on the vitamin D status of children in North China.

Methods

In this observational study, a total of 55,925 children aged 1 month to 18 years old were recruited from pediatric outpatient departments from July 2016 to June 2017. Data on demographics, anthropometric measurements, vitamin D intervention (either prescribed by physicians or given by parents) and outdoor activity were recorded. The serum levels of 25-hydroxycholecalciferol (25(OH)D) were determined by high performance liquid chromatography tandem–mass spectrometry. Logistic regression analysis was performed to assess the association of vitamin D intervention or outdoor activity with blood vitamin D status, adjusted for age, gender, BMI for age, and seasons.

Results

The overall rate of hypovitaminosis D was 65.60%. Of the children’s outdoor activity, 35.63, 31.95, and 32.42% were below 30 min/d, 30–60 min/d and over 60 min/d, respectively. Furthermore, the proportion of therapeutic intervention, supplementation intervention and no vitamin D intervention among the children was 16.48, 32.87, and 50.65%, respectively. After adjusted for confounding factors, vitamin D intervention was associated with a lower risk of hypovitaminosis D, with OR (95% CI) of 0.191 (0.180, 0.202) in children with therapeutic doses and 0.423 (0.404, 0.443) in those with supplementation doses, compared with children without vitamin D intervention. In addition, longer outdoor time was associated with a lower risk of hypovitaminosis D [0.479 (0.456, 0.504) for 60 min/d, 0.737 (0.701, 0.776) for 30–60 min/d], independent of vitamin D intervention.

Conclusions

High prevalence of vitamin D deficiency was found in children living at high latitudes. Vitamin D intervention and outdoor activity are all negatively associated with children’s vitamin D deficiency. Routine vitamin D intervention combined with increased outdoor time might be an effective approach to prevent hypovitaminosis D among children, especially those at school, living at high latitudes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-020-02435-9.