Vitamin D Status and Seasonal Variation among Danish Children and Adults: A Descriptive Study

Reference Intervals (RIs) of the Bone Turnover Markers (BTMs) in Children and Adolescents: A Proposal for Effective Use

BACKGROUND/OBJECTIVES

Bone turnover markers (BTMs) can provide information on the bone growth of apparently healthy children and adolescents or useful results in the diagnosis and monitoring of the disease condition, comparing them with appropriate reference intervals (RIs). The aim of this study was to establish the RI for the BTM [specific bone alkaline phosphatase (BALP), carboxy-terminal cross-linked collagen type I telopeptide (CTX), N-terminal propeptide pro-collagen type I (PINP), osteocalcin (OC), resistant to acid tartrate phosphatase isoform 5b (TRAcP-5b)] on serum samples from children and adolescents.

METHOD

202 samples from children and adolescents (ages 1-18 years) (51.48% male), considered apparently healthy. The biomarker was analyzed on automatic immunometric equipment (TGSTA Technogenetics) and the IDS-iSYS automated system kits The RI of the studied parameters was calculated according to CLSI Guideline C28-A3 with stratification by age and sex. Evaluation of the distribution of values and the meaning of the biomarker concentrations were used to calculate general and specific RI for an age group.

RESULTS

BTM concentrations vary with pubertal growth. The pattern of change differs for each bone marker. General and age-specific RI were calculated: 1-14 years, 15-18 years for BALP and CTX; 1-13 years, 14-18 years for Oc and PINP and 1-12 years, 13-18 years for TRAcP.

DISCUSSION AND CONCLUSIONS

Concentrations for biomarker studied vary with age and gender. The proof of concentrations with insignificant changes until puberty led to identification of two groups of RI relating to the covariables (age and sex) for each biomarker.

Vitamin D deficiency and duration of COVID-19 symptoms in UK healthcare workers

Objectives

Vitamin D has a role in the innate immunity against pathogens and is also involved in mechanisms for reducing inflammation. VD deficiency (VDD) may increase COVID-19 infection susceptibility, however research is limited on the association between VDD and COVID-19 symptom prevalence and duration. The study aimed to determine whether VDD is a risk factor for the presence and extended duration of COVID-19 symptoms.

Methods

Data was analyzed from NHS healthcare workers who isolated due to COVID-19 symptoms as a part of the COVID-19 convalescent immunity study between 12th to 22nd May 2020. Participants self-reported the presence and duration of viral symptoms. Anti-SARS-CoV-2 antibodies and vitamin D (25(OH)D3) serum levels were measured on day of recruitment. VDD was defined as 25(OH)D3 levels of < 30 nmol/l.

Results

Of the 392 participants, 15.6% (n = 61) had VDD. VDD participants had more symptoms overall (p = 0.0030), including body aches (p = 0.0453), and extended duration of body aches (p = 0.0075) and fatigue (p = 0.0127). Binary logistic regression found that both VDD (OR 3.069, 95% CI 1.538-6.124; p = 0.001) and age (OR 1.026, 95% CI 1.003-1.049; p = 0.025) were independently associated with extended durations of body aches. VDD (OR 2.089, 95% CI 1.087-4.011; p = 0.027), age (OR 1.036, 95% CI 1.016-1.057; p < 0.001) and seroconversion (OR 1.917, 95% CI 1.203-3.056; p = 0.006), were independently associated with extended durations of fatigue.

Conclusion

VDD is a significant independent risk factor for extended durations of body aches and fatigue in healthcare workers who isolated for COVID-19 viral symptoms. Vitamin D supplementation may reduce symptom duration and is thus an area for future research.

Is underweight associated with poorer diet, nutrient status, bone and cardiometabolic health, and school performance in Danish 8-11-year-olds?

PURPOSE

Underweight, i.e. low body mass index for age and sex, may indicate undernutrition, but despite high prevalence, this aspect is largely overlooked in children in high-income countries. We explored if dietary intake, nutrient status, body composition, bone mineralization, cardiometabolic markers and school performance differed in schoolchildren with underweight compared to normal- and overweight.

METHODS

We used cross-sectional data from 815 Danish 8-11-year-old children collected in 2011. Intake of foods, macronutrients and key micronutrients (vitamin D, vitamin B12, calcium, iron, zinc and selenium) was assessed by 7-day dietary records. Measurements included anthropometry, dual-energy X-ray absorptiometry and tests of attention and reading skills. Fasting blood samples were analyzed for biomarkers of iron, long-chain n-3 fatty acids and vitamin D status as well as blood lipids, insulin and growth markers.

RESULTS

Eighty-three (10.2%) children had underweight and were shown to have a lower intake of energy, red meat, protein and zinc and higher intake of added sugar than children with normal- and overweight. They also had higher fish intake relative to overweight, but blood biomarkers did not differ between groups. Children with underweight had lower fat percent and bone mineralization compared to peers with normalweight, but apart from lower insulin, they did not differ in overall cardiometabolic health or school performance.

CONCLUSION

Although we found some differences in diet, there were no considerable differences in nutrient status, cardiometabolic health or school performance between children with underweight and their normalweight peers. However, the lower bone mineralization is a concern and needs further investigation.

Vitamin D Status and Physical Functioning in Nursing Home Residents after Improved Adherence to the Vitamin D and Calcium Recommendation-A Quasiexperimental Study

Introduction

Dietary supplements with vitamin and calcium are recommended to nursing home residents in Denmark, but adherence to the recommendation is low. In a previous part of this study, we reported improved adherence by means of The Model for Improvement leading to increased awareness and change of workflows at two nursing homes. However, potential effects of this improved adherence are unknown.

Objective

The objective of this substudy was to investigate if the improved adherence to the recommendation affected vitamin D status, muscle strength, and physical functioning of the residents.

Methods

This was a 20-week quasiexperimental study involving 40 residents from two Danish nursing homes. Baseline and endpoint measurements took place in October 2021 and March 2022, respectively. Outcomes were number of residents taking vitamin D and calcium supplements; vitamin D status; handgrip strength; and physical functioning with timed-up-and-go test and 30-second chair stand test.

Results

Prevalence of vitamin D supplement users increased from 45 to 78% (mean dose 41 μg) and of calcium supplement users from 40 to 72% (mean dose 769 mg) (both P=0.002). Among those having blood sampled at both baseline and endpoint (n = 30), mean vitamin D status increased from 66.6 ± 31.7 nmol/L to 82.8 ± 26.3 nmol/L (P < 0.001), and more residents were vitamin D sufficient at endpoint (90 vs. 63%, P=0.021). Endpoint vitamin D status among supplement users was 88.2 ± 22.2 nmol/L, which was higher compared to nonsupplement users (55.3 ± 30.4 nmol/L, P < 0.01). No effects were seen on muscle strength or physical functioning.

Conclusions

Increased supplementation with vitamin D using The Model for Improvement positively affected vitamin D status and prevalence of vitamin D sufficiency but did not affect muscle strength or physical functioning. Longer-term studies involving more residents are needed to investigate effects of improved adherence on these outcomes. This trial is registered with NCT04956705.

Interaction and association between multiple vitamins and social adaptability and severity of autism: A large-scale retrospective study from China

Since children with autism spectrum disorder (ASD) often exhibit selective eating behaviors, it is generally believed that they may have abnormal nutrient structure, leading to aberrant concentrations of some serum vitamins. However, previous studies on serum vitamins in individuals with ASD are mixed. Additionally, the interaction and association between multiple serum vitamin and ASD-related symptoms remain unclear. This study utilized a cross-sectional survey with a large sample size (n = 1235) from China to clarify previous mixed findings, and examine the interaction and association between multiple serum vitamins (including folic acid [FA], vitamin A [VA], vitamin E [VE], vitamin B12 [VB12], and vitamin D [VD]) and social adaptability and symptom severity in children with ASD. Findings found that symptom severity was negatively associated with concentrations of serum VA, VE, VB12, and VD; while, social adaptability was significantly associated with the natural log-transformed concentrations of FA and VB12. Finding also revealed the interaction of VA and VE on the association between both vitamins and severity of ASD symptoms, as well as the interaction of VB12 and FA on the association between both vitamins and social adaptability. In particular, the combination of low concentration of VA and high concentration of VE is associated with the lowest risk of being "severely autistic"; while, the combination of low concentration of FA and high concentration of VB12 is associated with the lowest risk of being "poor social adaptability". This study offers the evidence for the requirement of considering multiple vitamins comprehensively, as well as valuable references for revealing the association between vitamin disparities and food selectivity in children with ASD.

Vitamin D Deficiency-A Public Health Issue in Children

BACKGROUND

25-hydroxyvitamin D [25(OH)D] deficiency is a global health concern, particularly in pediatric populations, with implications for musculoskeletal health and overall well-being. This study aimed to evaluate serum 25(OH)D levels in a pediatric population and assess the prevalence of deficiency and insufficiency.

METHODS

A retrospective analysis was conducted on data from 741 pediatric patients (2-17 years old) who visited an urban hospital for children for acute respiratory and gastrointestinal conditions in the span of 2 years. Serum 25(OH)D levels were measured using chemiluminescent microparticle immunoassay. Statistical analyses were performed to assess the prevalence of deficiency and insufficiency, seasonal variations, and correlations with age and daylight exposure.

RESULTS

Of the 739 pediatric patients analyzed, a substantial proportion exhibited insufficient (31.80%) or deficient (36.54%) serum 25(OH)D levels. While younger age groups generally had higher mean 25(OH)D levels, a negative correlation was observed between 25(OH)D levels and age. Sunlight exposure variations did not significantly impact serum 25(OH)D levels. Despite diverse daylight exposure patterns, there were no significant differences between longer and shorter daylight periods.

CONCLUSIONS

This study highlights the high prevalence of 25(OH)D deficiency and insufficiency in the pediatric population, emphasizing the need for public health monitoring and targeted supplementation strategies. Findings underscore the importance of regular consultations with healthcare providers to ensure optimal 25(OH)D levels in children, with potential implications for revising current sufficiency thresholds. Addressing 25(OH)D deficiency is crucial for promoting musculoskeletal health and overall well-being in children.

Assessment of serum vitamin D levels in children aged 0-17 years old in a Chinese population: a comprehensive study

Vitamin D deficiency and insufficiency pose global public health challenges, yet research on serum vitamin D levels in the 0-17-year-old age group in southeastern China remains limited. This study aimed to fill this gap by investigating serum 25(OH)D levels in children in the region aged 0-17 years, contributing crucial data for understanding vitamin D nutritional status. Liquid chromatography‒mass spectrometry/mass spectrometry (LC‒MS/MS) technology was used. Vitamin D testing was integrated into routine diagnostic procedures for 11,116 children in Wujiang District, Suzhou City. Among the 0-17-year age group, comprising 6348 boys and 4768 girls, the prevalence of serum 25(OH)D deficiency and insufficiency was 21.4% and 31.0%, respectively. The median serum 25(OH)D concentration was 29.72 ng/mL (21.84-39.84 ng/mL) in boys compared to 28.48 ng/mL (20.65-39.23 ng/mL) in girls. Seasonal variations were observed, with median serum 25(OH)D concentrations of 29.02 ng/mL (20.73-39.72 ng/mL) in spring, 28.79 ng/mL (21.53-39.37 ng/mL) in summer, 30.12 ng/mL (22.00-39.70 ng/mL) in autumn, and 28.58 ng/mL (19.97-39.46 ng/mL) in winter. Statistically significant differences were noted in the serum 25(OH)D levels during autumn and winter. In conclusion, the rate of adequate vitamin D levels in local children was 47.5%, revealing a relatively high prevalence of vitamin D deficiency (21.4%) and insufficiency (31.0%), especially during the post-preschool period. Advocating for vitamin D supplementation in children is crucial for ensuring adequate vitamin D support.

Vitamin D Status During Adolescence and the Impact of Lifestyle Changes: 2 Years' Follow-up From the Fit Futures Study

CONTEXT

Longitudinal data regarding vitamin D status in adolescence is scarce. This study presents population-based data from an Arctic adolescent population (n = 589) at 16 and 18 years.

OBJECTIVE

The aims of this study were to investigate changes in vitamin D status during 2 years in adolescence, and whether lifestyle changes were associated with serum 25-hydroxyvitamin D (s-25(OH)D) at follow-up.

METHODS

Fit Futures is a longitudinal study at 69°N in Norway. Participants had their s-25(OH)D levels analyzed in their first and third year of upper secondary school (median age 16 and 18 years), in Fit Futures 1 (FF1) and Fit Futures 2 (FF2), respectively. Self-reported lifestyle habits were registered through questionnaires. The association between lifestyle changes and s-25(OH)D levels at follow-up were calculated by regression analyses, controlling for baseline s-25(OH)D levels.

RESULTS

Longitudinal data were available for 309 girls and 280 boys. The proportion of adolescents with s-25(OH)D <50 nmol/L were 73.7% in FF1 and 77.1% in FF2, while the proportion <30 nmol/L constituted 35.7% in FF1 and 40.9% in FF2. Of those with s-25(OH)D <30 nmol/L (severe vitamin D deficiency) in FF1, 73.3% remained severely deficient in FF2. Among boys, an increase in UV exposure was significantly associated with higher s-25(OH)D levels in FF2 (beta; CI [nmol/L] 12.9; 9.1, 16.7). In girls, decreased vitamin/mineral supplement intake was significantly associated with lower s-25(OH)D at FF2 (-6.7; -10.2, -3.1), while increased UV (10.8; 7.0, 14.7) and combined hormonal contraceptive exposure (12.1; 6.0, 18.1) in FF2 was significantly associated with higher s-25(OH)D levels in FF2.

CONCLUSION

Severe vitamin D deficiency was prevalent throughout adolescence. Lifestyle changes may alter s-25(OH)D levels in this age group.

Confirming the association between low serum 25OHD levels in girls with central precocious puberty and its severity

BACKGROUND

To assess the differences in vitamin D levels in girls with rapidly progressive (RP) or slowly progressive (SP) central precocious puberty (CPP) and to compare whether the factors related to RP-CPP influenced the vitamin D status. A cross-sectional study was performed among girls with CPP classified as RP-CPP or SP-CPP.

METHODS

The baseline data, gonadotropin-releasing hormone (GnRH) stimulation test results, serum 25-hydroxyvitamin D (25OHD) levels, and season of sample collection were analyzed.

RESULTS

The mean 25OHD level in 340 girls was 15.89 ± 6.87 ng/mL, of whom only 10 (2.9%) had normal levels (≥ 30 ng/mL). A total of 114 girls in the SP-CPP group and 226 in the RP-CPP group had similar chronological age, disease course, height SDS, bone mineral density, baseline follicle-stimulating hormone (FSH), peak FSH, and 25OHD levels. Developmental age, body mass index (BMI), BMI SDS, peak luteinizing hormone (LH)/FSH, insulin-like growth factor 1 (IGF-1), and IGF-1 SDS were independent risk factors for RP-CPP. Significant differences were observed among the different serum 25OHD levels in terms of season, disease course, IGF1 level, and BMI SDS (P < 0.05). Moreover, the sampling season was strongly correlated with serum 25OHD levels (r = 0.402, P < 0.001).

CONCLUSION

The vitamin D levels were generally deficient or insufficient in girls with CPP, but were not related to the different types of CPP. High BMI levels, IGF1 levels, or peak LH/FSH ratio, but not vitamin D levels, could promote the progression of RP-CPP. Seasonal factors mainly influenced the vitamin D levels.

RETROSPECTIVE OBSERVATIONAL STUDY OF VITAMIN D STATUS IN NEUROLOGICAL PATIENTS

The main objective of this study was to investigate the prevalence of insufficient serum 25-hydroxyvitamin D level in a sample of neurological patients and to compare it to the estimate in the general Croatian population. The secondary aim was to test for the possible significant differences in vitamin D2 insufficiency between the groups of patients according to gender, season, region, vitamin D3 supplementation, and diagnosis of autoimmune disease. This retrospective study involved 371 neurological patients in one-year period. The data collected included gender, age at the time of admission, region, season at the time of admission, main neurological diagnosis at discharge, serum 25-hydroxyvitamin D level at the time of hospitalization, and use of vitamin D3 substitutes prior to hospitalization. The proportion of neurological patients with 25-hydroxyvitamin D insufficiency (<75 nmol/L) was estimated at 74.66% (95% confidence interval, p<0.0001), which is slightly lower than in the Croatian general population. There were no significant differences in 25-hydroxyvitamin D insufficiency according to gender, season and region. Significant differences in 25-hydroxyvitamin D insufficiency were found according to vitamin D3 supplementation and diagnosis of autoimmune disease.

Effect of Vitamin D in Long COVID Patients

Vitamin D deficiency has been studied in the context of acute coronavirus disease 2019 (COVID-19), revealing associations with increased severity and mortality. Yet, the influence of vitamin D on long COVID symptoms remains unknown. The purpose of this study is to examine the effect of vitamin D on long COVID symptoms. Over the study period, 50,432 individuals within the catchment area of the outpatient COVID-19 clinic tested positive for SARS-CoV-2 via PCR, with 547 patients subsequently referred to a specialized Post-COVID Clinic, and 447 of them enrolled in the study. Patient-reported symptoms and paraclinical measures including vitamin D were evaluated in 442 patients. The majority of participants were female (72%, n = 320/442). The consumption of alcohol and number of current smokers were low. Low vitamin D was observed in 26% (n = 115/442) of the patients, most commonly in male participants (odds ratio (OR) = 1.77, 95% confidence interval (CI) (1.12, 2.79), p = 0.014). Additionally, low vitamin D was correlated with a younger mean age of 41 years (standard deviation (SD) = 12) as opposed to 48 years (SD = 13) in patients with normal vitamin D levels (OR = 0.96, 95% CI (0.94, 0.97), p < 0.001). While our study population indicated a potentially higher prevalence of vitamin D insufficiency in this population compared to the general population, no significant differences in prevalence of symptom or symptom severity scores were observed between the low and normal vitamin D groups. In patients in a Post-COVID Clinic, we found no association between vitamin D levels and long COVID symptoms.

The estimated effect of season and vitamin D in the first trimester on pubertal timing in girls and boys: a cohort study and an instrumental variable analysis

BACKGROUND

Season of birth has been associated with age at menarche. Maternal vitamin D levels in pregnancy may explain this effect. We investigated whether the season of first trimester or maternal 25-hydroxyvitamin D3 [25(OH)D3] levels were associated with pubertal timing in children.

METHODS

We conducted a follow-up study of 15 819 children born in 2000-03 from the Puberty Cohort, nested in the Danish National Birth Cohort (DNBC). Mean differences in attaining numerous pubertal markers, including a combined estimate for the average age at attaining all pubertal markers, were estimated for low (November-April) relative to high (May-October) sunshine exposure season in the first trimester using multivariable interval-censored regression models. Moreover, we conducted a two-sample instrumental variable analysis using season as an instrument for maternal first-trimester 25(OH)D3 plasma levels obtained from a non-overlapping subset (n = 827) in the DNBC.

RESULTS

For the combined estimate, girls and boys of mothers who had their first trimester during November-April had earlier pubertal timing than girls and boys of mothers whose first trimester occurred during May-October: -1.0 months (95% CI: -1.7 to -0.3) and -0.7 months (95% CI: -1.4 to -0.1), respectively. In the instrumental variable analysis, girls and boys also had earlier pubertal timing: respectively, -1.3 months (95% CI: -2.1 to -0.4) and -1.0 months (95% CI: -1.8 to -0.2) per SD (22 nmol/L) decrease in 25(OH)D3.

CONCLUSIONS

Both first pregnancy trimester during November-April and lower 25(OH)D3 were associated with earlier pubertal timing in girls and boys.

Senior citizens' vitamin D supplements intake: evidence from Denmark

BACKGROUND

Several public interventions have been designed in recent years to urge the intake of vitamin D supplements among the senior population to avoid the direct and indirect consequences associated with vitamin D deficiency. However, the effectiveness of these public campaigns remains quite limited. In an online survey, the current study investigates attitudes towards vitamin D supplements intake and associated behaviours in a representative sample of Danish senior citizens (N = 554) - that is, individuals aged 55 years and above.

RESULTS

Approximately half of the sample reported taking vitamin D supplements in the preceding year. Furthermore, being male and having a positive perception of individuals' own health status increased the probability of being a non-user. Increasing confidence in the information provided by health authorities (such as medical doctors and pharmacies) is particularly critical for enhancing the likelihood of non-users to purchase vitamin D supplements. However, also encouraging the uptake of vitamin D supplements in specialized supermarkets with stands and promotions seems an appealing and practical solution to increase seniors' uptake of vitamin D supplements.

CONCLUSIONS

The present study outlines the characteristics of senior Danish non-users of vitamin D supplements. Additionally, the research provides information on the strategies that could be applied by public organizations to foster vitamin D supplements intake among this target segment of the population. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Vitamin D deficiency and development of complications in individuals with type 1 and type 2 diabetes: A cohort study

AIMS

To investigate vitamin D deficiency as a risk marker for complications in individuals with type 1 and type 2 diabetes.

METHODS

A cohort study including 1448 adults with type 1 and 770 with type 2 diabetes. Individuals in the decile with lowest vitamin D level were classified as vitamin D deficient. Outcomes based on medical records and registers included mortality, major adverse cardiovascular event (MACE), heart failure, a composite kidney endpoint, albuminuria progression and sight-threatening eye disease. Risk in individuals with vitamin D deficiency was compared to the remaining using adjusted Cox proportional hazards models.

RESULTS

Vitamin D deficiency was associated with higher risk of MACE (adjusted hazard ratio (HR): 2.6; 95 % confidence interval (CI): 1.3-5.2) in type 1, but not in type 2 diabetes. Risk of heart failure was higher in individuals with vitamin D deficiency in both cohorts (HR (95%CI): 16 (4.8-50) in type 1 and 2.4 (1.1-5.5) in type 2 diabetes). Vitamin D deficiency was not associated with development of microvascular complications or mortality.

CONCLUSIONS

Vitamin D deficiency was a risk marker for MACE and heart failure in type 1 and for heart failure in type 2 diabetes, but not for microvascular complications or all-cause mortality.

Maternal vitamin D levels and male reproductive health: a population-based follow-up study

Maternal vitamin D levels during pregnancy may be important for reproductive health in male offspring by regulating cell proliferation and differentiation during development. We conducted a follow-up study of 827 young men from the Fetal Programming of Semen Quality (FEPOS) cohort, nested in the Danish National Birth Cohort to investigate if maternal vitamin D levels were associated with measures of reproductive health in adult sons. These included semen characteristics, testes volume, and reproductive hormone levels and were analysed according to maternal vitamin D (25(OH)D3) levels during pregnancy. In addition, an instrumental variable analysis using seasonality in sun exposure as an instrument for maternal vitamin D levels was conducted. We found that sons of mothers with vitamin D levels < 25 nmol/L had 11% (95% CI - 19 to - 2) lower testes volume and a 1.4 (95% CI 1.0 to 1.9) times higher risk of having low testes volume (< 15 mL), in addition to 20% (95% CI - 40 to 9) lower total sperm count and a 1.6 (95% CI 0.9 to 2.9) times higher risk of having a low total sperm count (< 39 million) compared with sons of mothers with vitamin D levels > 75 nmol/L. Continuous models, spline plots and an instrumental variable analysis supported these findings. Low maternal vitamin D levels were associated with lower testes volume and lower total sperm count with indications of dose-dependency. Maternal vitamin D level above 75 nmol/L during pregnancy may be beneficial for testes function in adult sons.

Vitamin D Determinants, Status, and Antioxidant/Anti-inflammatory-Related Effects in Cardiovascular Risk and Disease: Not the Last Word in the Controversy

Beyond its key role in calcium homeostasis, vitamin D has been found to significantly affect the cardiovascular (CV) system. In fact, low vitamin D levels have been associated with increased CV risk, as well as increased CV morbidity and mortality. The majority of effects of this molecule are related directly or indirectly to its antioxidative and anti-inflammatory properties. Generally, vitamin D insufficiency is considered for 25-hydroxyvitamin D (25(OH)D) levels between 21-29 ng/mL (corresponding to 52.5-72.5 nmol/L), deficiency as 25(OH)D levels less than 20 ng/mL (<50 nmol/L), and extreme deficiency as 25(OH)D less than 10 ng/mL (<25 nmol/L). However, the definition of an optimal vitamin D status, as defined by 25(OH)D, remains controversial for many extra-bone conditions, including CV disease. In this review, confounding factors affecting the 25(OH)D measurement and status will be discussed. In particular, available evidence on the mechanism and role of vitamin D in relation to CV risk and disease through its antioxidant effect will be reported, also facing the aspect regarding the debate on the minimum blood 25(OH)D level required to ensure optimal CV health.

Serum 25-hydroxyvitamin D status of a large Chinese population from 30 provinces by LC-MS/MS measurement for consecutive 3 years: differences by age, sex, season and province

PURPOSE

We aimed to describe the vitamin D status and its distribution in different age groups, sexes, seasons, and provinces of a large Chinese population.

METHODS

This study retrospectively analyzed 1,528,685 results of serum 25-hydroxyvitamin D (25(OH)D) in the central laboratory of KingMed Diagnostics. The samples were from the individuals aged 0-119 years old in 30 provinces of China. Serum 25(OH)D was measured by an accurate commercial liquid chromatography-tandem mass spectrometry (LC-MS/MS) method from January 2017 to December 2019. The subjects were stratified by age, sex, the season of blood collection, and the province of residence.

RESULTS

The median 25(OH)D concentration was 25.5 ng/mL (interquartile range (IQR) 18.7-32.7 ng/mL) in males and 20.8 ng/mL (IQR 14.4-28.2 ng/mL) in females. Overall, the median 25(OH)D concentration decreased with age in both males and females. Males had a 0.2-2.4 ng/mL higher median 25(OH)D concentration than females in different age groups. Vitamin D deficiency (25(OH)D < 15 ng/mL for the individuals under 14 years old; < 20 ng/mL for the individuals over 14 years old) was found in 21.3% of males and 43.6% of females. Significant seasonal variation of serum 25(OH)D concentrations was repeatedly observed in 3 years, with median concentration higher in summer (25.3 ng/mL (IQR 19.3-31.9 ng/mL)) and lower in winter (18.5 ng/mL (IQR 12.3-26.6 ng/mL)). Vitamin D status varied by province. The median 25(OH)D concentration was the highest in Hainan (31.0 ng/mL (IQR 24.9-39.2 ng/mL)) and the lowest in Qinghai (14.4 ng/mL (IQR 9.6-20.0 ng/mL)). 25(OH)D₂ was detected in 12.2% of the results, and no significant seasonal variation was observed.

CONCLUSION

In China, vitamin D deficiency is prevalent in the population participating in clinical vitamin D measurement. Age and sex differences in vitamin D levels were observed in our study. Seasonal variation and provincial differences are important aspects of serum vitamin D status. 25(OH)D₂ cannot be ignored entirely in clinical measurement practice in China.

Vitamin D status of 3-year-old children in Denmark: determinants and associations with bone mineralisation and blood lipids

PURPOSE

Low vitamin D status is a global problem and has been associated with reduced skeletal and cardiometabolic health. However, evidence in young children is lacking. We, therefore, aimed to characterise vitamin D status in toddlers, identify its determinants, and explore if vitamin D status was associated with bone mineralisation and lipid profile.

METHODS

We used cross-sectional data from 3-year-old children (n = 323) living in Denmark (latitude: 55°N). Bone mineralisation (n = 108) was measured by DXA. Blood samples were analysed for serum 25-hydroxyvitamin D (s-25(OH)D) by LC-MS/MS, triacylglycerol, and total, low- and high density lipoprotein cholesterol.

RESULTS

Mean ± SD s-25(OH)D was 69 ± 23 nmol/L, but varied with season. During winter, 38% had inadequate s-25(OH)D (< 50 nmol), whereof 15% had deficiency (< 30 nmol/L); these numbers were only 7 and 1% during summer. In terms of status determinants, supplement use (66% were users) was associated with s-25(OH)D (P < 0.001), whereas dietary vitamin D intake (median [25-75^th percentile] of 1.3 [0.9-1.9] µg/d), sex, parental education, BMI, and physical activity were not. There were no associations between s-25(OH)D and blood lipids or bone measurements, using either unadjusted or adjusted regression models.

CONCLUSION

More than 1/3 of Danish toddlers had inadequate vitamin D intake during winter, but acceptable mean vitamin D status. In addition to season, supplement use was the main determinant of vitamin D status, which was, however, not associated with bone mineralisation or lipid profile. The results support recommendations of vitamin D supplements during winter at northern latitudes, but potential health effects need further investigation.

Vitamin D, a Regulator of Androgen Levels, Is Not Correlated to PSA Serum Levels in a Cohort of the Middle Italy Region Participating to a Prostate Cancer Screening Campaign

Prostate cancer (PCa) is the most common non-cutaneous malignancy in men worldwide, and it represents the fifth leading cause of death. It has long been recognized that dietary habits can impact prostate health and improve the benefits of traditional medical care. The activity of novel agents on prostate health is routinely assessed by measuring changes in serum prostate-specific antigen (PSA) levels. Recent studies hypothesized that vitamin D supplementation reduces circulating androgen levels and PSA secretion, inhibits cell growth of the hormone-sensitive PCa cell lines, counteracts neoangiogenesis and improves apoptosis. However, the results are conflicting and inconsistent. Furthermore, the use of vitamin D in PCa treatments has not achieved consistently positive results to date. In order to assess the existence of a correlation between the PSA and 25(OH)vitamin D levels as widely hypothesized in the literature, we analyzed the serum PSA and 25(OH)vitamin D concentration on a cohort of one hundred patients joining a PCa screening campaign. Additionally, we performed medical and pharmacological anamnesis and analyzed lifestyle, as sport practice and eating habits, by administering a questionnaire on family history. Although several studies suggested a protective role of vitamin D in PCa onset prevention and progression, our preliminary results revealed a clear absence of correlation between the serum vitamin D and PSA concentration levels, suggesting that vitamin D has no impact on PCa risk. Further investigations enrolling a huge number of patients are needed with particular attention to vitamin D supplementation, calcium intake, solar radiation that influences vitamin D metabolism and other potential indicators of health to confirm the absence of correlation observed in our study.

Bone Turnover Markers in Children: From Laboratory Challenges to Clinical Interpretation

Bone turnover markers (BTMs) have been developed many years ago to study, in combination with imaging techniques, bone remodeling in adults. In children and adolescents, bone metabolism differs from adults since it implies both growth and bone remodeling, suggesting an age- and gender-dependent BTM concentration. Therefore, specific studies have evaluated BTMs in not only physiological but also pathological conditions. However, in pediatrics, the use of BTMs in clinical practice is still limited due to these many children-related specificities. This review will discuss about physiological levels of BTMs as well as their modifications under pathological conditions in children and adolescents. A focus is also given on analytical and clinical challenges that restrain BTM usefulness in pediatrics.

Sources of vitamin D and determinants of serum 25-hydroxyvitamin D in Finnish adolescents

PURPOSE

To study the intake and sources of vitamin D and determinants of serum 25-hydroxyvitamin D (S-25(OH)D) in Finnish adolescents.

METHODS

We studied 265 adolescents (117 girls) aged 15-17 years attending 8-year examinations of the PANIC Study, assessed diet using food records and other lifestyle factors by questionnaires, and analyzed S-25(OH)D by chemiluminescence immunoassay and determinants of S-25(OH)D using multivariate linear regression.

RESULTS

Mean (standard deviation) of total vitamin D intake from food and supplements was 19.2 (13.1) µg/d, and that of dietary vitamin D intake was 9.9 (5.4) µg/d. Milk fortified with vitamin D was the main dietary source of vitamin D, providing 45% of daily intake. Altogether, 29% of the adolescents used no vitamin D supplements and 25% did not meet the recommended total vitamin D intake of 10 µg/d. Mean (standard deviation) of S-25(OH)D was 62.0 (18.8) nmol/l, and S-25(OH)D was < 50 nmol/l in 29.5% of the adolescents. Vitamin D intake from supplements was the main determinant of S-25(OH)D (β = 0.465, p < 0.001), followed by consumption of milk products (β = 0.251, p < 0.001), consumption of meat products (β = 0.179, p = 0.002), travels to sunny countries (β = 0.178, p = 0.002), and average daylight time (β = 0.162, p = 0.004).

CONCLUSION

Most of the adolescents had vitamin D intake at the recommended level, although a fourth did not meet the recommended total vitamin D intake of 10 µg/d and almost a third had S-25(OH)D < 50 nmol/l. More attention should be paid to the sufficient intake of vitamin D in adolescents who do not use vitamin D supplements or fortified milk products.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01803776, registered March 3, 2013.

Vitamin D and Calcium Supplementation in Nursing Homes-A Quality Improvement Study

Even though dietary supplements with vitamin D and calcium are recommended to nursing home residents, we recently reported a low adherence to this recommendation. The objective of this 20-week quality improvement study was to use the Model for Improvement and Plan-Do-Study-Act (PDSA) cycles to improve adherence in Danish nursing homes. We included two nursing homes with 109 residents at baseline. An information sheet including the rationale for the recommendation was developed for the nurses to urge residents to take the supplements and seek approval by the general practitioner afterwards (PDSA cycle 1). Moreover, it was included in admission meetings with new residents to address supplementation (PDSA cycle 2). A nurse reviewed patient records for number of residents prescribed adequate doses of vitamin D (≥20 µg) and calcium (≥800 mg) before, during and after the intervention. At baseline, 32% (n = 35) of the residents had adequate doses of vitamin D and calcium. After implementation of the information sheet and adjustment to admission meetings, this increased to 65% (n = 71) at endpoint (p < 0.001). In conclusion, in this quality improvement study, we improved the number of prescriptions of adequate doses of vitamin D and calcium over 20 weeks using the Model for Improvement and PDSA experiments.

Vitamin D status and severity of COVID-19

We explored the association between COVID-19 severity and vitamin D status using information from Danish nation-wide health registers, the COVID-19 surveillance database and stored blood samples from the national biobank. 25-hydroxyvitamin D (25(OH)D) was measured using tandem mass spectroscopy. The association between 25(OH)D levels and COVID-19 severity, classified hierarchical as non-hospitalized, hospitalized but not admitted to an intensive care unit (ICU), admitted to ICU, and death, was evaluated by proportional odds ratios (POR) assuming proportionality between the four degrees of severity. Among 447 adults tested SARS-CoV-2 positive in the spring of 2020, low levels of 25(OH)D were associated with a higher risk of severe COVID-19. Thus, odds of experiencing more severe COVID-19 among individuals with insufficient (25 to < 50 nmol/L) and sufficient (≥ 50 nmol/L) 25(OH)D levels were approximately 50% of that among individuals with deficient levels (< 25 nmol/L) (POR = 0.49 (95% CI 0.25-0.94), POR = 0.51 (95% CI 0.27-0.96), respectively). Dividing sufficient vitamin D levels into 50 to < 75 nmol/L and ≥ 75 nmol/L revealed no additional beneficial effect of higher 25(OH)D levels. In this observational study, low levels of 25(OH)D were associated with a higher risk of severe COVID-19. A possible therapeutic role of vitamin D should be evaluated in well-designed interventional studies.

Vitamin D status and parathyroid hormone assessment in girls with central precocious puberty

PURPOSE

The objective of this study was to analyze vitamin D status and PTH concentrations in 6- to 8-year-old girls with central precocious puberty.

METHODS

A cross-sectional clinical and blood testing study (calcium, phosphorus, 25(OH)D and PTH) was carried out in 78 girls with central precocious puberty (CPP group), aged 6.1-7.9 years. A control group was recruited (137 prepubertal girls, aged 6.1-8.2 years). The criteria of the US Endocrine Society were used for the definition of hypovitaminosis D.

RESULTS

There were no significant differences in vitamin D status between both groups. There were no significant differences in 25(OH)D concentrations between CPP (25.4 ± 8.6 ng/mL) and control groups (28.2 ± 7.4 ng/mL). In contrast, PHT concentrations in CPP group (44.8 ± 16.3 pg/mL) were higher (p < 0.05) with respect to control group (31.0 ± 11.9 ng/mL). In CPP group, there was a positive correlation (p < 0.05) between PTH concentrations and growth rate, bone age, and basal estradiol, basal FSH, basal LH and LH peak concentrations.

CONCLUSION

Vitamin D status in 6- to 8-year-old girls with CPP is similar to that in prepubertal girls. PTH concentrations were significantly higher in girls with CPP, and this could be considered as a physiological characteristic of puberty and, in this case, of pubertal precocity.

The Diurnal Blood Metabolome and Effects of Vitamin D Supplementation: A Randomised Crossover Trial in Postmenopausal Women

A way to maintain an adequate vitamin D status is through supplementation. Demonstration of blood-metabolome rhythmicity of vitamin D3 post-dosing effects is lacking in the pharmaco-metabonomics area. Thus, the overall aim of this study was to investigate the diurnal changes in the blood metabolome and how these are affected by vitamin D3 supplementation. The study was conducted as a crossover study, and the treatment included 200 µg (8000 IU) of vitamin D3 as compared with placebo with a washout period of at least 10 days. The participants were postmenopausal women aged 60−80 years (N = 29) with vitamin D insufficiency (serum 25-hydroxyvitamin D < 50 nmol/L) but otherwise healthy. During the intervention day, blood samples were taken at 0 h, 2 h, 4 h, 6 h, 8 h, 10 h, 12 h, and 24 h, and plasma was analysed by proton nuclear magnetic resonance (NMR) spectroscopy as a metabolomics approach. In general, diurnal effects were identified for the majority of the 20 quantified metabolites, and hierarchical cluster analysis revealed a change in the overall plasma metabolome around 12 AM (6 h after intervention), suggesting that the diurnal rhythm is reflected in two diurnal plasma metabolomes; a morning metabolome (8−12 AM) and an afternoon/evening metabolome (2−8 PM). Overall, the effect of vitamin D supplementation on the blood metabolome was minor, with no effect on the diurnal rhythm. However, a significant effect of the vitamin D supplementation on plasma acetone levels was identified. Collectively, our findings reveal an influence of diurnal rhythm on the plasma metabolome, while vitamin D supplementation appears to have minor influence on fluctuations in the plasma metabolome.

Comparison of the Serum Total 25-Hydroxyvitamin D Concentrations Using Chemiluminescent Immunoassay and Liquid Chromatography-Tandem Mass Spectrometry in Children

We aimed to assess the difference and agreement between the CL-series Vitamin D Total assay (Mindray), which was a kind of chemiluminescent immunoassay (CLIA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the measurement of serum 25-hydroxyvitamin D [25(OH)D] concentrations in children. We compared the 25(OH)D concentrations of 92 children using the CLIA and LC-MS/MS. Paired samples t-test was used to compare the two groups. Linear regression was used to show the correlation between CLIA and LC-MS/MS. The difference and bias between 2 methods were revealed in Bland-Altman plot. Agreement in classification of deficiency between CLIA and LC-MS/MS was assessed using Cohen's Kappa. p value<0.05 was considered statistically significant. Using Shapiro-Wilk Test to assess whether the data follows a normal distribution. Using 95% children's serum 25(OH)D concentrations by LC-MS/MS as the reference interval. The regression equation was CLIA=1.185×LC-MS/MS-3.328. The fitness adjusted r² was 0.589. The CLIA showed positive bias compared to LC-MS/MS, p<0.05, bias=(1.94±16.56) ng/mL. Cohen's Kappa=0.53, p<0.001. The agreement of 2 methods in diagnosing "deficiency" was good. According to Shapiro-Wilk Test, the data followed a normal distribution (W=0.99). The reference interval of children's serum 25(OH)D concentrations by LC-MS/MS was 11.35-44.57 ng/mL. In measuring 25(OH)D concentration of children, CLIA represented higher levels than LC-MS/MS. The two methods were consistent in diagnosing vitamin D deficiency. The reference interval of children's serum 25(OH)D concentrations by LC-MS/MS was 11.35-44.57 ng/mL in our area in summer.

25-Hydroxyvitamin D reference percentiles and the role of their determinants among European children and adolescents

BACKGROUND/OBJECTIVES

To provide age- and sex-specific percentile curves of serum 25-hydroxyvitamin D (25(OH)D) by determinants from 3-<15 year-old European children, and to analyse how modifiable determinants influence 25(OH)D.

SUBJECTS/METHODS

Serum samples were collected from children of eight European countries participating in the multicenter IDEFICS/I.Family cohort studies. Serum 25(OH)D concentrations were analysed in a central lab by a chemiluminescence assay and the values from 2171 children (N = 3606 measurements) were used to estimate percentile curves using the generalized additive model for location, scale and shape. The association of 25(OH)D with time spent outdoors was investigated considering sex, age, country, parental education, BMI z score, UV radiation, and dietary vitamin D in regressions models.

RESULTS

The age- and sex-specific 5th and 95th percentiles of 25(OH)D ranged from 16.5 to 73.3 and 20.8 to 79.3 nmol/l in girls and boys, respectively. A total of 63% had deficient (<50 nmol/l), 33% insufficient (50-<75 nmol/l) and 3% sufficient (≥75 nmol/l) levels. 25(OH)D increased with increasing UV radiation, time spent outdoors, and vitamin D intake and slightly decreased with increasing BMI z score and age. The odds ratio (OR) for a non-deficient 25(OH)D status (reference category: deficient status) by one additional hour spent outdoors was 1.21, 95% CI [1.12-1.31], i.e., children who spent one more hour per day outdoors than other children had a 21% higher chance of a non-deficient than a deficient status.

CONCLUSION

A majority of children suffer from deficient 25(OH)D. UV radiation, outdoor time, and dietary vitamin D are important determinants of 25(OH)D.

Exocrine pancreas insufficiency in chronic pancreatitis - Risk factors and associations with complications. A multicentre study of 1869 patients

BACKGROUND/OBJECTIVES

There is scarce information about risk factors for exocrine pancreas insufficiency (EPI) in chronic pancreatitis (CP), and how it associates with other complications. The aim of the present study was to examine risk factors for EPI and associations to procedures and other CP related complications in a large, Northern European cohort.

PATIENTS AND METHODS

We retrieved cross-sectional data on demographics, status on EPI, aetiological risk factors for CP, CP related complications as well as surgical and endoscopic treatment from the Scandinavian Baltic Pancreatic Club Database. Associations were assessed by univariate and multivariate logistic regression analyses. Results are presented as odds ratios (OR) with 95% confidence intervals.

RESULTS

We included 1869 patients with probable or definitive CP in the study. Exocrine pancreas insufficiency was present in 849 (45.4%) of patients. In multivariate analyses, EPI associated with smoking aetiology (OR 1.47 (1.20-1.79), p < 0.001), and nutritional/metabolic aetiology (OR 0.52 (0.31-0.87), p = 0.01) to CP. Pancreatic or common bile duct stenting procedure and pancreatic resection were both associated with EPI (ORs 1.44 (1.15-1.80), p = 0.002 and 1.54 (1.02-2.33), p = 0.04, respectively). The presence of diabetes mellitus (OR 2.45 (1.92-3.15), p < 0.001), bile duct stenosis (OR 1.48 (1.09-2.00), p = 0.02) and underweight (2.05 (OR 1.40-3.02), p < 0.001) were all associated with presence of EPI.

CONCLUSIONS

Smoking, bile duct stenosis, previous stenting and resection procedures are all associated with EPI in patients with CP. Presence of EPI were also associated with malnutrition and diabetes mellitus. Hence, intensive nutritional surveillance is needed in these patients.

Vitamin D Counteracts Lipid Accumulation, Augments Free Fatty Acid-Induced ABCA1 and CPT-1A Expression While Reducing CD36 and C/EBPβ Protein Levels in Monocyte-Derived Macrophages

The biologically active form of vitamin D, calcitriol (VD3), has received great attention for its extraskeletal effects, such as a protective role on the cardiovascular system. The aim of the present work is to test the capacity of VD3 to affect lipid metabolism and fatty acid accumulation in an in vitro model of monocyte (THP-1)-derived macrophages. Cells were treated for 24 h with oleic/palmitic acid (500 μM, 2:1 ratio) and different VD3 concentrations (0.1, 1, 10, 50 and 100 nM). Lipid accumulation was quantified spectrophotometrically (excitation: 544 nm, emission: 590 nm). C/EBPβ, PPAR-γ1, CD36, CPT-1A, and ABCA1 protein levels were assessed by ELISA kits at different time-points (1, 2, 4, 8, and 24 h). VD3 at 50 and 100 nM significantly reduced fatty acids accumulation in macrophages by 27% and 32%, respectively. In addition, tested at 50 nM, VD3 decreased CD36, PPAR-γ1, and C/EBPβ, while it increased ABCA1 and CPT-1A protein levels in free fatty acid-exposed cells. In conclusion, VD3 reduced fatty acid accumulation in THP-1-derived macrophages exposed to lipid excess. The anti-atherogenic effect of VD3 could be ascribable to the regulation of proteins involved in lipid transport and clearance.

Bio-Fortified Pork Cracklings with UVB LED Tailored Content of Vitamin D3

Since few foods are naturally rich in vitamin D, novel food products with a high content of vitamin D are needed to decrease the prevalence of vitamin D deficiency. Pork cracklings are Danish snacks with high contents of protein and fat. They are consumed mostly during wintertime when sun exposure cannot fulfil human needs for vitamin D3. Pork cracklings were produced in an industrially friendly manner from UVB LED illuminated pork rind, using a combination of sous vide (85 °C, 60 min) and roasting in the oven (200 °C, 20 min). Thermal processing resulted in a significant loss of vitamin D3 (>90%). Thus, the process was optimized by the UVB exposure of pork cracklings, i.e., after thermal processing. The produced pork cracklings had a vitamin D3 level of ~10 µg/100 g, with a possibility of tailoring its final content. Furthermore, the fat content at 15−20% was a reduction of 50% compared to marketed products in 2021. No significant difference was found in the content of vitamin D3 during 31 days of storage in the air. A consumer preference test (n = 53) indicated that >80% of participants liked the product and saw its potential as a new food source of vitamin D3.

Vitamin D Status and Health Outcomes in School Children in Northern Ireland: Year One Results from the D-VinCHI Study

(1) Background: Vitamin D status has never been investigated in children in Northern Ireland (UK). (2) Methods: Children (4-11 years) (n = 47) were recruited from November 2019 to March 2020 onto the cross-sectional study. Anthropometry was assessed. Plasma 25-hydroxyvitamin D (25(OH)D) was analysed. Vitamin D intake, parental knowledge and perceptions, participant habits, physical activity and sedentary behaviour were established via questionnaire. Muscle strength was assessed via isometric grip strength dynamometry and balance via dominant single-leg and tandem stance. Parathyroid hormone, bone turnover markers (OC, CTX and P1NP), glycated haemoglobin and inflammatory markers (CRP, IFN-γ, IL-10, IL-12p70, IL-13, IL-1β, IL-2, IL-4, IL-6, IL-8 and TNF-α) were analysed. (3) Results: Mean (SD) 25(OH)D was 49.17 (17.04) nmol/L (n = 47); 44.7% of the children were vitamin D sufficient (25(OH)D >50 nmol/L), 48.9% were insufficient (25-50 nmol/L) and 6.4% were deficient (<25 nmol/L). 25(OH)D was positively correlated with vitamin D intake (µg/day) (p = 0.012, r = 0.374), spring/summer outdoor hours (p = 0.006, r = 0.402) and dominant grip strength (kg) (p = 0.044, r = 0.317). Vitamin D sufficient participants had higher dietary vitamin D intake (µg/day) (p = 0.021), supplement intake (µg/day) (p = 0.028) and spring/summer outdoor hours (p = 0.015). (4) Conclusion: Over half of the children were vitamin D deficient or insufficient. Wintertime supplementation, the consumption of vitamin D rich foods and spring/summer outdoor activities should be encouraged to minimise the risk of vitamin D inadequacy.

Parathormone, bone alkaline phosphatase and 25-hydroxyvitamin D status in a large cohort of 1200 children and teenagers

Objectives: 25-Hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH) and bone alkaline phosphatase (BALP) are biomarkers of calcium/phosphate metabolism and bone turnover. Although vitamin D deficiency is a well-known cause of secondary hyperparathyroidism, few studies have considered vitamin D status when establishing reference ranges. In this study, we report PTH levels according to the vitamin D status and BALP levels in a large cohort of 1200 children. Additionally, we provide PTH pediatric reference values according to 25(OH)D status as well as BALP pediatric reference ranges.Methods: Serum samples from 1200 children (equally distributed from 5 months to 20 years old) who underwent blood sampling for allergy exploration were used to quantify 25(OH)D, PTH and BALP.Results: The percentage of vitamin D deficient children (<20 ng/ml) progressively increased during childhood starting from 7% in the 0 to 2 year-old subgroup to a mean of at least 50% among teenagers. PTH levels inversely mirrored 25(OH)D concentrations for all age and gender subgroups, and 25(OH)D deficient subgroups presented higher PTH levels than their non-deficient counterparts. In the non-deficient 25(OH)D population, PTH levels were the highest at 11 years old for girls and 14 years old for boys. BALP results were slightly increased during childhood and showed a constant decrease during teenage years starting from 12 years old for girls and 14 years old for boys.Conclusion: Our results highlight the inverse relationship between PTH and 25(OH)D in children and the need for a well characterized 25(OH)D population to establish pediatric reference ranges for PTH.

Effects of vitamin D-related gene polymorphisms on attempted suicide

OBJECTIVE

Emerging evidence suggests that vitamin D might protect from attempted suicide. The study aimed to investigate the associations between single-nucleotide polymorphisms (SNPs) related to vitamin D levels identified in a large genome-wide association study and attempted suicide in rural China.

METHODS

This 1:1 matched case-control study included altogether 510 suicide attempters and 510 community controls. Genotypes of four target SNPs (DHCR7-rs12785878, CYP2R1-rs10741657, GC-rs2282679, and CYP24A1-rs6013897) were determined, and a genetic risk score (GRS) was constructed to evaluate the combined effect of them. Demographic and psychological information was acquired through face-to-face interviews.

RESULTS

The A allele of CYP24A1-rs6013897 was significantly associated with attempted suicide (OR = 1.27, 95% CI, 1.03-1.58, P = 0.029), even after adjusting for demographic and psychological confounders (adjusted OR = 1.53, 95% CI, 1.01-2.30, P = 0.043). The GRS analyses revealed a significantly higher risk of attempted suicide with a greater number of low vitamin D alleles (adjusted OR = 1.33, 95% CI, 1.13-1.58, P < 0.001). Subgroup analyses stratified by sex indicated that the genetic associations were only significant among males with adjusted ORs of 3.77 (95% CI, 1.56-9.10) for the A allele of rs6013897 and 2.04 (95% CI, 1.32-3.17) for GRS.

CONCLUSIONS

Our findings identity CYP24A1-rs6013897 as a potential biomarker for attempted suicide and indicate that a genetic predisposition to lower vitamin D levels may contribute to attempted suicide. It suggests the possibility that vitamin D may have the preventive potential for attempted suicide.

The effect of vitamin D recommendations on serum 25-hydroxyvitamin D level in patients with erythropoietic protoporphyria

OBJECTIVES

Patients with erythropoietic protoporphyria (EPP) avoid sun exposure owing to photosensitivity. For decades, sun-avoiding Danes have been recommended daily vitamin D supplements all year. We offered our EPP patients serum 25-hydroxyvitamin D (25(OH)D) monitoring, and counseling if their level was low. We aimed to investigate the effect of the general recommendation and counseling on 25(OH)D status in patients attending our clinic. Additionally, the 25(OH)D status of our EPP patients was compared to that of British patients with EPP not taking vitamin D supplements and with that of the general Danish population.

METHODS

Forty-six Danish patients with EPP had 25(OH)D measured in 721 blood samples collected between 2003 and 2021. Dates of individual counseling were noted. Data on British patients with EPP and the general Danish population were extracted from previous publications.

RESULTS

Our patients had higher 25(OH)D levels than British patients with EPP not taking vitamin D supplements, but the recommendations did not elevate their 25(OH)D levels to that of the general Danish population. Overall, 17.5% of the 25(OH)D measurements in our EPP patients were below 30 nmol/L (deficiency) and 29.4% were between 30 and 50 nmol/L (insufficiency). Patients were monitored for a median of 11 y. Thirty-one patients had a total of 74 vitamin D counseling sessions, providing an increase in 25(OH)D of about 18 nmol/L the year after. However, many patients repeatedly developed insufficiency.

CONCLUSIONS

This study documents the positive effect of vitamin D recommendations on serum 25(OH)D in patients with EPP. Follow-up on vitamin D status and recommendations is essential to increase 25(OH)D levels.

The use of ketogenic diets in cancer patients: a systematic review

Ketogenic diets are a widely known, yet controversial treatment for cancer patients. In this review, we summarize the clinical evidence for anti-tumor effects, as well as the effects on anthropometry, quality of life, adverse events and adherence in cancer patients. In April 2019, a systematic search was conducted searching five electronic databases (EMBASE, Cochrane, PsychInfo, CINAHL and Medline) to find studies analyzing the use, effectiveness and potential harm of a ketogenic diet in cancer patients of any age as sole or complementary therapy. From all 19.211 search results, 46 publications concerning 39 studies with 770 patients were included in this systematic review. The therapy concepts included all forms of diets with reduced carbohydrate intake, that aimed to achieve ketosis for patients with different types of cancer. Most studies had a low quality, high risk of bias and were highly heterogeneous. There was no conclusive evidence for anti-tumor effects or improved OS. The majority of patients had significant weight loss and mild to moderate side effects. Adherence to the diet was rather low in most studies. Due to the very heterogeneous results and methodological limitations of the included studies, clinical evidence for the effectiveness of ketogenic diets in cancer patients is still lacking.

Population-based pediatric reference values for serum parathyroid hormone, vitamin D, calcium, and phosphate in Danish/North-European white children and adolescents

INTRODUCTION

Parathyroid hormone (PTH) and vitamin D are essential hormones in bone metabolism, especially during pediatric growth. Vitamin D insufficiency is often asymptomatic and is prevalent in high-latitude countries.

METHODS

In a Danish population-based cohort of 2211 6-18-year-olds, sex- and age-specific pediatric reference values for fasting concentrations of intact serum PTH, vitamin D (25-hydroxycholecalciferol, 25-OH-D), total calcium, and phosphate were generated in accordance with Clinical and Laboratory Standards Institute (CLSI) EP28-A3c guidelines. The effect of season on these biomarkers of bone metabolism was evaluated.

RESULTS

In boys, PTH concentrations increased with age, while the vitamin D and phosphate concentrations decreased (all p < .001). In girls, a peak in PTH concentrations and a nadir in vitamin D concentrations were observed in the 10-14-year-olds (both p < .001). Calcium and phosphate decreased with age for both sexes (girls: both p < .001; boys calcium: p < .05, boys phosphate: p < .001). Vitamin D was 20% lower in winter than summer for both sexes (both p < .001). Individuals with vitamin D sufficiency (25-OH-D > 50 nmol/L) exhibited a 5% lower level of PTH compared to the whole sample population (p < .001).

CONCLUSION

The concentrations of PTH, vitamin D, calcium, and phosphate vary during childhood and adolescence, and is dependent on sex and season. These factors should be considered when screening for and treating imbalances in bone metabolism.

Global Public Interests and Dynamic Trends in Osteoporosis From 2004 to 2019: Infodemiology Study

Background

With the prolonging of human life expectancy and subsequent population aging, osteoporosis (OP) has become an important public health issue.

Objective

This study aimed to understand the global public search interests and dynamic trends in “osteoporosis” using the data derived from Google Trends.

Methods

An online search was performed using the term “osteoporosis” in Google Trends from January 1, 2004, to December 31, 2019, under the category “Health.” Cosinor analysis was used to test the seasonality of relative search volume (RSV) for “osteoporosis.” An analysis was conducted to investigate the public search topic rising in RSV for “osteoporosis.”

Results

There was a descending trend of global RSV for “osteoporosis” from January 2004 to December 2014, and a slowly increasing trend from January 2015 to December 2019. Cosinor analysis showed significant seasonal variations in global RSV for “osteoporosis” (P=.01), with a peak in March and a trough in September. In addition, similar decreasing trends of RSV for “osteoporosis” were found in Australia, New Zealand, Ireland, and Canada from January 2004 to December 2019. Cosinor test revealed significant seasonal variations in RSV for “osteoporosis” in Australia, New Zealand, Canada, Ireland, UK, and USA (all P<.001). Furthermore, public search rising topics related to “osteoporosis” included denosumab, fracture risk assessment tool, bone density, osteopenia, osteoarthritis, and risk factor.

Conclusions

Our study provided evidence about the public search interest and dynamic trends in OP using web-based data, which would be helpful for public health and policy making.

Optical coherence tomography quantifying photo aging: skin microvasculature depth, epidermal thickness and UV exposure

INTRODUCTION

Photo aging predominantly occurs in the face, neck and hands due to UVA and UVB irradiation. It is associated with skin cancer and histological studies indicate thinning of the epidermis and elastosis occurs. Dynamic Optical coherence tomography (D-OCT) is a non-invasive imaging tool able to visualize the epidermis and upper dermis and its blood vessels as well as to evaluate epidermal thickness (ET) and blood flow.

OBJECTIVE

To investigate ET and blood vessel depth using D-OCT in human subjects correlated to UV exposure.

METHODS

We evaluated data from 249 healthy adults, that had D-OCT-scans conducted at four different regions (forehead, neck, arm and hand) and correlated ET and blood vessel depth with occupational UV exposure (total standard erythema dose, Total SED), season and demographic data.

RESULTS

Regional differences in ET and blood vessel depth were found (p values < 0.001). Multiple linear regressions showed a seasonal effect on both ET (- 0.113 to - 0.288 µm/day, p values < 0.001) and blood vessel depth (0.168-0.347 µm/day, p values < 0.001-0.007) during August-December. Significant age-related decrease of ET was seen in forehead, arm and hand (0.207-0.328 µm/year, p values = 0.002-0.18) and blood vessel depth in forehead (0.064-0.553 µm/year, p values = 0.01-0.61). Males had thicker epidermis (3.92-10.93 µm, p values = 0.002-0.15).

CONCLUSION

Changing seasons are a major predictor of both ET and blood vessel depth, showing strongest effect in non-exposed areas, suggesting a systemic effect, possibly due to seasonal vitamin D fluctuation. Sex, age and occupational UV exposure affect ET. This study demonstrated the feasibility of D-OCT to evaluate epidermal thickness and blood vessel depth.

The Impact of COVID-19 Pandemic during 2020-2021 on the Vitamin D Serum Levels in the Paediatric Population in Warsaw, Poland

BACKGROUND

The main source of vitamin D is skin synthesis, which depends on sunlight exposure. During the pandemic, COVID-19 children were obliged to home confinement, which potentially limiting sunlight exposure. The aim of this study was to evaluate whether home confinement led to decreased vitamin D serum levels in children in Warsaw, Poland.

METHODS

The study included 1472 children who were divided into two groups, based on the date of 25(OH)D level blood sampling: before and during the pandemic. Children under 1 year of age (infants) were analysed separately.

RESULTS

A statistically significant decrease in the average level of vitamin D was observed between groups of children over 1 year of age (35 ng/mL ± 18 vs. 31 ng/mL ± 14). In infants from both groups, the mean vitamin D levels were within the normal range (Group 1 inf 54 ng/mL ± 21 vs. Group 2 inf 47 ng/mL ± 15). The characteristic seasonal variability was observed before the pandemic, with maximal vitamin D levels in summer (40 ng/mL ± 17) and minimal levels in winter (30 ng/mL ± 14). During the pandemic, no seasonal variability was observed (summer 30 ng/mL ± 11 vs. winter 30 ng/mL ± 19).

CONCLUSIONS

The COVID-19 pandemic restrictions led to a significant decrease in vitamin D serum levels in children.

Impact of vitamin D deficiency on COVID-19

Background & aims

COVID-19 has emerged as a global pandemic affecting millions of people. Vitamin D deficiency is one of the risk factors for increased susceptibility to COVID-19. This study aimed to examine the correlation between the prevalence of vitamin D deficiency and COVID-19 infection and mortality rates among the adult population in European and Asian continents.

Methods

Prevalence of vitamin D deficiency in each country was retrieved through literature searching on PubMed® database for the last ten years. As of December, 31^st 2020, COVID-19 infections and mortalities per million population were extracted from the ‘real time’ statistics of the Worldometer website. The association between both vitamin D deficiency and COVID-19 infections and mortalities were explored.

Results

Forty seven countries were included in the analysis. The prevalence of vitamin D deficiency ranged from 6.9 to 81.8% in European countries and 2.0–87.5% in Asian countries. Significantly positive correlations were observed for both COVID-19 infection (r = 0.76; p < 0.001) and mortality rates (r = 0.75; p < 0.001) in the Asian continent. The correlation values for the infections and mortality rates in the European continent were (r = 0.37; p = 0.08) and (r = 0.43; p = 0.04) respectively. When both the continents were combined, the correlation results for both infection (r = 0.42; p = 0.003) and mortality (r = 0.35; p = 0.016) rates with vitamin D deficiency values remained significant.

Conclusion

Prevalence of vitamin D deficiency was significantly associated with the mortality rate of COVID-19 in Europe and Asia. The association between the infection rate and prevalence of vitamin D deficiency was significant for Asia only. Both the associations were significant when the two continents were combined in the analysis. Therefore we suggest that vitamin D supplementation could play a key role in the prevention and/or treatment of the COVID-19 patients.

Sex disparities in vitamin D status and the impact on systemic inflammation and survival in rectal cancer

BACKGROUND

We reported previously that rectal cancer patients given curative-intent chemotherapy, radiation, and surgery for non-metastatic disease had enhanced risk of metastatic progression and death if circulating levels of 25-hydroxyvitamin D [25(OH) D] were low. Here we investigated whether the association between the vitamin D status and prognosis pertains to the general, unselected population of rectal cancer patients.

METHODS

Serum 25(OH) D at the time of diagnosis was assessed in 129 patients, enrolled 2013-2017 and representing the entire range of rectal cancer stages, and analyzed with respect to season, sex, systemic inflammation, and survival.

RESULTS

In the population-based cohort residing at latitude 60°N, 25(OH) D varied according to season in men only, who were overrepresented among the vitamin D-deficient (< 50 nmol/L) patients. Consistent with our previous findings, the individuals presenting with T4 disease had significantly reduced 25(OH) D levels. Low vitamin D was associated with systemic inflammation, albeit with distinct modes of presentation. While men with low vitamin D showed circulating markers typical for the systemic inflammatory response (e.g., elevated erythrocyte sedimentation rate), the corresponding female patients had elevated serum levels of interleukin-6 and the chemokine (C-X-C motif) ligand 7. Despite disparities in vitamin D status and the potential effects on disease attributes, significantly shortened cancer-specific survival was observed in vitamin D-deficient patients irrespective of sex.

CONCLUSION

This unselected rectal cancer cohort confirmed the interconnection of low vitamin D, more advanced disease presentation, and poor survival, and further suggested it may be conditional on disparate modes of adverse systemic inflammation in men and women.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01816607 ; registration date: 22 March 2013.

Early-Life Factors Are Associated with Vitamin D Status in Early and Mid-Childhood and May Differ between White and Black Children

BACKGROUND

Suboptimal vitamin D (VitD) status has been associated with poor bone health and other adverse health outcomes and is common among children. Various early-life factors are associated with child VitD, yet few studies have examined multiple factors simultaneously in a single study population.

OBJECTIVES

We aimed to characterize relations of early-life factors with plasma 25-hydroxyvitamin D [25(OH)D] concentrations in early and mid-childhood, and to explore potential differences in these associations between white and black children.

METHODS

We identified associations of various early-life factors with 25(OH)D concentrations in early and mid-childhood among 961 children in Project Viva using linear regression models. All variables associated with 25(OH)D were included together in final multivariable models at each outcome time point: 1 in the overall sample and additional models for children whose mothers identified them as being white or black.

RESULTS

Overall mean ± SD 25(OH)D concentrations were 86 ± 29 nmol/L in early childhood and 68 ± 21 nmol/L in mid-childhood. After accounting for other predictors, children who took VitD supplements (compared with those who did not) had 25(OH)D concentrations 5.6 nmol/L (95% CI: 2.0, 9.2 nmol/L) higher in early childhood and 8.2 nmol/L (95% CI: 4.8, 11.6 nmol/L) higher in mid-childhood. Other factors consistently associated with higher 25(OH)D were blood collection in summer or fall, white race, nonfall birth season, prenatal exposure to higher 25(OH)D, and higher dietary intake of VitD. Greater waist circumference was associated with lower 25(OH)D in early childhood (β: -3.8; 95% CI: -7.4, -0.2 per 1-SD increase) among black children only.

CONCLUSIONS

Our findings may help clinicians better target children at risk of lower 25(OH)D for screening and/or intervention and may inform research focused on associations of 25(OH)D with different exposures and outcomes or causal effects of early-life factors on later VitD status.This trial was registered at clinicaltrials.gov as NCT02820402.

Vitamin D levels and the risk of prostate cancer and prostate cancer mortality

BACKGROUND

Vitamin D has a role in bone turnover and potentially bone-metastatic spread of prostate cancer (PCa). The aim of this observational study was to address the association between levels of serum vitamin D, diagnosis of PCa and subsequent mortality in men who underwent a biopsy of the prostate.

METHODS

All men who underwent prostatic biopsy in the Danish PCa Registry (DaPCaR) and who had a serum vitamin D measurement during the period 2004 to 2010 (n = 4,065) were identified. Men were categorized by clinical cut-offs based on seasonally adjusted serum vitamin D levels in <25 (deficient), 25-50 (insufficient), 50-75 (sufficient) and >75 nmol/L (high) serum vitamin D. Logistic regression model for association between vitamin D and risk of PCa diagnosis and multivariate survival analyses were applied.

RESULTS

No association between serum vitamin D and risk of PCa was found. Overall survival was lowest for serum vitamin D deficiency and a significantly higher PCa specific mortality (HR: 2.37, 95%CI: 1.45-3.90, p < .001) and other cause mortality (HR: 2.08, 95%CI: 1.33-3.24, p = .001) was found for PCa patients with serum vitamin D deficiency compared to serum vitamin D sufficiency.

CONCLUSION

No association was found between serum vitamin D categories and risk of PCa in men who underwent biopsy of the prostate. Men with PCa and serum vitamin D deficiency had a higher overall and PCa specific mortality compared to men with a sufficient level of serum vitamin D.

The effect of weather, air pollution and seasonality on the number of patient visits for epileptic seizures: A population-based time-series study

OBJECTIVE

The objective of the study was to explore the influences of seasonality, meteorological conditions, and air pollution exposure on the number of patients who visit the hospital due to seizures.

METHODS

Outpatient and inpatient data from the National Health Insurance Database of Taiwan from 2009 to 2013, meteorological data from the Meteorological Bureau, and air pollution exposure data from the Taiwan Air Quality Monitoring Stations were collected and integrated into daily time series data. The following data processing and analysis results are based on the mean of the 7 days' lag data of the 18 meteorological condition/air pollution exploratory factors to identify the critical meteorological conditions and air pollution exposure factors by executing univariate analysis. The average hospital visits for seizure per day by month were used as an index of observation. The effect of seasonality has also been examined.

RESULTS

The average visits per day by month had a significant association with 10 variables. Overall, the number of visits due to these factors has been estimated to be 71.529 (13.7%). The most obvious factors affecting the estimated number of visits include ambient temperature, CH₄, and NO. Six air pollutants, namely CH₄, NO, CO, NO₂, PM2.5, and NMHC had a significantly positive correlation with hospital visits due to seizures. Moreover, the average daily number of hospital visits was significantly high in January and February (winter season in Taiwan) than in other months (R² = 0.422).

CONCLUSION

The prediction model obtained in this study indicates the necessity of rigorous monitoring and early warning of these air pollutants and climate changes by governments. Additionally, the study provided a firm basis for establishing prediction models to be used by other countries or for other diseases.

Vegan diet in young children remodels metabolism and challenges the statuses of essential nutrients

Vegan diets are gaining popularity, also in families with young children. However, the effects of strict plant-based diets on metabolism and micronutrient status of children are unknown. We recruited 40 Finnish children with a median age 3.5 years-vegans, vegetarians, or omnivores from same daycare centers-for a cross-sectional study. They enjoyed nutritionist-planned vegan or omnivore meals in daycare, and the full diets were analyzed with questionnaires and food records. Detailed analysis of serum metabolomics and biomarkers indicated vitamin A insufficiency and border-line sufficient vitamin D in all vegan participants. Their serum total, HDL and LDL cholesterol, essential amino acid, and docosahexaenoic n-3 fatty acid (DHA) levels were markedly low and primary bile acid biosynthesis, and phospholipid balance was distinct from omnivores. Possible combination of low vitamin A and DHA status raise concern for their visual health. Our evidence indicates that (i) vitamin A and D status of vegan children requires special attention; (ii) dietary recommendations for children cannot be extrapolated from adult vegan studies; and (iii) longitudinal studies on infant-onset vegan diets are warranted.

Perspective: Vitamin D deficiency and COVID-19 severity - plausibly linked by latitude, ethnicity, impacts on cytokines, ACE2 and thrombosis

BACKGROUND

SARS-CoV-2 coronavirus infection ranges from asymptomatic through to fatal COVID-19 characterized by a 'cytokine storm' and lung failure. Vitamin D deficiency has been postulated as a determinant of severity.

OBJECTIVES

To review the evidence relevant to vitamin D and COVID-19.

METHODS

Narrative review.

RESULTS

Regression modelling shows that more northerly countries in the Northern Hemisphere are currently (May 2020) showing relatively high COVID-19 mortality, with an estimated 4.4% increase in mortality for each 1 degree latitude north of 28 degrees North (P = 0.031) after adjustment for age of population. This supports a role for ultraviolet B acting via vitamin D synthesis. Factors associated with worse COVID-19 prognosis include old age, ethnicity, male sex, obesity, diabetes and hypertension and these also associate with deficiency of vitamin D or its response. Vitamin D deficiency is also linked to severity of childhood respiratory illness. Experimentally, vitamin D increases the ratio of angiotensin-converting enzyme 2 (ACE2) to ACE, thus increasing angiotensin II hydrolysis and reducing subsequent inflammatory cytokine response to pathogens and lung injury.

CONCLUSIONS

Substantial evidence supports a link between vitamin D deficiency and COVID-19 severity but it is all indirect. Community-based placebo-controlled trials of vitamin D supplementation may be difficult. Further evidence could come from study of COVID-19 outcomes in large cohorts with information on prescribing data for vitamin D supplementation or assay of serum unbound 25(OH) vitamin D levels. Meanwhile, vitamin D supplementation should be strongly advised for people likely to be deficient.