Vitamin D status in healthy Romanian caregivers and risk of respiratory infections

Low Vitamin K Status in Patients with Psoriasis Vulgaris: A Pilot Study

Psoriasis vulgaris (PV) is a disease characterized by skin manifestations and systemic inflammation. There are no published studies to date on vitamin K status assessed by extrahepatic vitamin K-dependent proteins [e.g., osteocalcin (OC) and matrix Gla protein (MGP)] in patients with PV, even if vitamin K was found to promote wound contraction and decrease the healing time of the skin. Metabolic syndrome (MS), a comorbidity of PV, was found to influence vitamin K status, and vitamin D was found to be involved in the pathogenesis of PV. Therefore, our aim was to assess the status of vitamins K and D in subjects with PV. We enrolled 44 patients with PV and 44 age- and sex-matched subjects as a control group (CG), of which individuals with MS were designated the CG with MS subgroup. Furthermore, the PV patients were stratified into two subgroups: those with MS (n = 20) and those without MS (n = 24). In addition to the quantification of vitamin D and MGP in all subjects, the uncarboxylated OC/carboxylated OC (ucOC/cOC) ratio was also assessed as an inversely proportional marker of vitamin K status. We found an increased ucOC/cOC ratio in the PV group compared to CG but also a greater ucOC/cOC ratio in the PV with MS subgroup than in the CG with MS subgroup. MGP was decreased in the PV with MS subgroup compared to CG with MS subgroup. There was no difference in the vitamin D concentration between the groups. This is the first study to report decreased vitamin K status in patients with PV, independent of the presence of MS.

Acute Respiratory Tract Infection and 25-Hydroxyvitamin D Concentration: A Systematic Review and Meta-Analysis

Observational studies and randomised controlled studies suggest that vitamin D plays a role in the prevention of acute respiratory tract infection (ARTI); however, findings are inconsistent and the optimal serum 25-hydroxyvitamin D (25(OH)D) concentration remains unclear. To review the link between 25(OH)D concentration and ARTI, we searched PubMed and EMBASE databases to identify observational studies reporting the association between 25(OH)D concentration and risk or severity of ARTI. We used random-effects meta-analysis to pool findings across studies. Twenty-four studies were included in the review, 14 were included in the meta-analysis of ARTI risk and five in the meta-analysis of severity. Serum 25(OH)D concentration was inversely associated with risk and severity of ARTI; pooled odds ratios (95% confidence interval) were 1.83 (1.42-2.37) and 2.46 (1.65-3.66), respectively, comparing the lowest with the highest 25(OH)D category. For each 10 nmol/L decrease in 25(OH)D concentration, the odds of ARTI increased by 1.02 (0.97-1.07). This was a non-linear trend, with the sharpest increase in risk of ARTI occurring at 25(OH)D concentration < 37.5 nmol/L. In conclusion, there is an inverse non-linear association between 25(OH)D concentration and ARTI.

Vitamin D levels and deficiency with different occupations: a systematic review

Background

Vitamin D deficiency is prevalent worldwide, but some groups are at greater risk. We aim to evaluate vitamin D levels in different occupations and identify groups vulnerable to vitamin D deficiency.

Methods

An electronic search conducted in Medline, Embase, the Cochrane Central Register of Controlled Trials, and CINAHL Plus with Full Text generated 2505 hits; 71 peer-reviewed articles fulfilled the inclusion criteria. Occupations investigated included outdoor and indoor workers, shiftworkers, lead/smelter workers, coalminers, and healthcare professionals. We calculated the pooled average metabolite level as mean ± SD; deficiency/insufficiency status was described as % of the total number of subjects in a given category.

Results

Compared to outdoor workers, indoor workers had lower 25-hydroxyvitamin D (25-(OH)D) levels (40.6 ± 13.3 vs. 66.7 ± 16.7 nmol/L; p < 0.0001). Mean 25-(OH)D levels (in nmol/L) in shiftworkers, lead/smelter workers and coalminers were 33.8 ± 10.0, 77.8 ± 5.4 and 56.6 ± 28.4, respectively. Vitamin D deficiency (25-(OH)D < 50 nmol/L), was high in shiftworkers (80%) and indoor workers (78%) compared to outdoor workers (48%). Among healthcare professionals, medical residents and healthcare students had the lowest levels of mean 25-(OH)D, 44.0 ± 8.3 nmol/L and 45.2 ± 5.5 nmol/L, respectively. The mean 25-(OH)D level of practising physicians, 55.0 ± 5.8 nmol/L, was significantly different from both medical residents (p < 0.0001) and healthcare students (p < 0.0001). Nurses and other healthcare employees had 25-(OH)D levels of 63.4 ± 4.2 nmol/L and 63.0 ± 11.0 nmol/L, respectively, which differed significantly compared to practising physicians (p = 0.01), medical residents (p < 0.0001) and healthcare students (p < 0.0001).

Rates of vitamin D deficiency among healthcare professionals were: healthcare students 72%, medical residents 65%, practising physicians 46%, other healthcare employees 44%, and nurses 43%. Combined rates of vitamin D deficiency or insufficiency (25-(OH)D < 75 nmol/L) were very high in all investigated groups.

Potential confounders such as gender and body composition were not consistently reported in the primary studies and were therefore not analyzed. Furthermore, the descriptions of occupational characteristics may be incomplete. These are limitations of our systematic review.

Conclusions

Our review demonstrates that shiftworkers, healthcare workers and indoor workers are at high risk to develop vitamin D deficiency, which may reflect key lifestyle differences (e.g. sunlight exposure). This may help target health promotion and preventive efforts.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-017-4436-z) contains supplementary material, which is available to authorized users.

Association of serum 25-hydroxyvitamin D with influenza in case-control study nested in a cohort of Japanese employees

BACKGROUND & AIMS

Several intervention studies have examined the effect of vitamin D supplementation on influenza or influenza-like illness, but their results have been inconsistent. We prospectively examined the association of serum 25-hydroxyvitamin D with influenza among Japanese workers.

METHODS

We conducted a nested case-control study in a cohort of workers in 4 companies in the Kanto and Tokai areas of Japan. Physician-diagnosed influenza that occurred during the winter season was ascertained using a self-administered questionnaire. Two controls matched by company, sex, and age (and checkup date in 1 company) were selected for each case. Serum 25-hydroxyvitamin D concentrations at baseline were measured using a competitive protein binding assay. Odds ratio of influenza were estimated by conditional logistic regression with adjustment for covariates.

RESULTS

Of 182 cases and 364 controls, 179 cases and 353 controls with complete data were included in the analysis. Serum 25-hydroxyvitamin D concentrations were not associated with a significantly lower risk of influenza; the multivariable-adjusted odds ratio for the highest (≥30 ng/mL) versus lowest category (<20 ng/mL) was 0.77 (95% confidence interval 0.37-1.59) (P for trend = 0.80). In a subgroup of participants without vaccination, vitamin D sufficiency (≥30 ng/mL) was associated with a significantly lower risk of influenza (odds ratio 0.14; 95% confidence interval 0.03-0.74).

CONCLUSIONS

Overall, circulating 25-hydroxyvitamin D concentrations were not appreciably associated with influenza episodes. However, the lower influenza risk associated with vitamin D sufficiency among unvaccinated participants warrants further investigation.

THE PREVALENCE OF BIOCHEMICAL ABNORMALITIES OF CHRONIC KIDNEY DISEASE. MINERAL AND BONE DISORDERS IN UNTREATED NON-DIALYSIS PATIENTS - A MULTICENTER STUDY

BACKGROUND

There are scarce data about prevalence of mineral metabolism (MM) disorders in Romanian predialysis patients, so we assessed their occurrence and relationships in mild to severe chronic kidney disease (CKD).

METHODS

One hundred fifteen non-dialysis CKD (eGFR 31, 95% CI 29-35mL/min) and 33 matched non-CKD subjects entered this multicentric, cross-sectional study. Serum 25-hydroxyvitamin D (25OHD), intact parathyroid hormone (iPTH), phosphate (PO4), total calcium (tCa) and alkaline phosphatase (AP) were measured, along with demographic and past medical history data.

RESULTS

Hypovitaminosis D was equally prevalent in Controls and CKD (91% vs. 96% had 25OHD<30ng/mL). Increasing proportions of hyperparathyroidism (33% - stage 2 to 100% - stage 5; p<0.001) and hyperphosphatemia (2% - stage 3 to 38% - stage 5; p<0.001) were found. Hypocalcemia was more prevalent in stage 5 (25% vs. 6% in stage 4, none in stage 3 and Controls, p<0.001). Mineral metabolism parameters correlated with eGFR. In addition, iPTH was directly associated with PO4, AP, and urinary albumin-to-creatinine ratio (ACR), but inversely with tCa and 25OHD, while negative correlation of 25OHD with age, AP, ACR, and C-reactive protein emerged. In multiple regression, eGFR was the only predictor of iPTH (Beta -0.68, 95%CI -1.35 to -0.90, R2 0.46, p<0.001), whereas age and ACR were the determinants of 25OHD (a model which explained 14% of its variation).

CONCLUSIONS

Hypovitaminosis D was very common irrespective of CKD presence and severity, and it seems worsened by older age and higher albuminuria. Hyperparathyroidism preceded hyperphosphatemia and hypocalcemia, and it seems mostly dependent on kidney function decline.

Vitamin D Status: A Different Story in the Very Young versus the Very Old Romanian Patients

BACKGROUND

In Romania (latitude 48°15'N to 43°40'N), vitamin D supplementation is common practice mostly in infants 0-1 year old. No published information is available regarding epidemiological data on vitamin D status in the Romanian population for a wide age range and geographical territory. In this context, we aimed to evaluate the seasonal and age variation of vitamin D status in a large Romanian population.

METHODS

6631 individuals from across Romania had performed 7544 vitamin D assessments (2012-2014) in a chain of private laboratories. Vitamin D (25-hydroxyvitamin D2 and 25-hydroxyvitamin D3) was measured using High Performance Liquid Chromatography. Vitamin D levels were classified as severe deficiency<10 ng/mL, deficiency 10-20 ng/mL, insufficiency 21-29 ng/mL, sufficiency ≥ 30 ng/mL and potentially harmful>100 ng/ml.

RESULTS

Male to female ratio was 1:2.9. Age ranged from 0 to 85 years. Mean vitamin D levels increased from April (26.3n g/ml) to September (35.6 ng/ml) and decreased from October (33.5 ng/ml) to March (24.4 ng/ml). Overall 40% had sufficient vitamin D, while the rest were insufficient 33%, deficient 22%, severely deficient 4% and 1% potentially harmful (of them 81% under 1 year old). Males compared to females showed higher percentages of sufficiency (47% vs. 38%). Children 0- 2 years presented the highest percentage of vitamin D sufficiency (77%). Lowest percentages (21%) of sufficiency were in people 80-84 years.

CONCLUSION

In Romania, suboptimal vitamin D levels are common (59%), especially in older age, wintertime and in women. Vitamin D supplementation would be most warranted from January to April in the Romanian population. 25-hydroxyvitamin D levels > 100 ng/ml were relatively prevalent in children 0-1 year old (17.3%). This was attributed to supplementation errors and the fact that high-risk individuals were more likely to visit for medical check-up. Nonetheless, it stresses the need to increase awareness of the importance of preventing Vitamin D supplementation administration errors in the young.

Evaluation of vitamin D level in patients from neurosurgical intensive care unit

Vitamin D plays an important role in maintaining normal bone metabolism. Recent studies have suggested that vitamin D influences many other physiological processes, including muscle function, cardiovascular homeostasis, nerve function, and immune response. Furthermore, accumulated evidence suggests that vitamin D also mediates the immune system response to infection. Critical neurosurgical patients have higher infection and mortality rates. To correlate vitamin D deficiency to the immunological status of neurosurgical intensive care unit patients, we detected serum vitamin D level in 15 patients with clinically suspected infection and 10 patients with confirmed infection. Serum level of 25-hydroxyvitamin D, the primary circulating form of vitamin D, was significantly decreased in patients with suspected or confirmed infection after a 2-week neurosurgical intensive care unit hospitalization, while serum level of 1,25-dihydroxyvitamin D, the active form of vitamin D, was significantly decreased in patients after a 4-week neurosurgical intensive care unit hospitalization. These findings suggest that vitamin D deficiency is linked to the immunological status of neurosurgical intensive care unit patients and vitamin D supplementation can improve patient's immunological status.

Does vitamin D protect against respiratory viral infections?

The active form of vitamin D has effects on both innate and adaptive immune responses that may influence the outcome in many infectious diseases. Observational studies conclusively show that a low vitamin D status is associated with an increased occurrence of respiratory viral infections, which globally represent significant health and financial burdens. However, no consistent protective effects are evident in prospective clinical trials carried out to date where vitamin D was provided as a dietary supplement, except possibly in cases where the starting vitamin D status of the individual was considered deficient. Thus far, vitamin D has not been found to enhance the immune response to vaccines. The design of future prospective clinical trials assessing a role for vitamin D in respiratory viral infections requires very careful planning to avoid the uncertainties associated with the data available currently.

The relationship between the metabolic syndrome and its components and bone status in postmenopausal women

The association between metabolic syndrome (MS) and bone status remains controversial. We aimed to study the relationships between MS, bone mineral density (BMD), and bone metabolism in postmenopausal women.

MATERIAL AND METHODS

MS was assessed in 218 white postmenopausal women. BMD (lumbar spine and hip) was measured by dual energy X-ray absorptiometry (DXA). Serum carboxyterminal cross-linked telopeptide of type 1 collagen (CTX), undercarboxylated osteocalcin (uOC), bone alkaline phosphate (BAP) and vitamin D were assayed.

RESULTS

Postmenopausal women with MS had a significantly higher lumber spine BMD than women without MS (p < 0.05). A progressive increase of the BMD at both sites with the number of MS components was observed. Bone turnover markers and vitamin D levels were not significantly influenced by the presence of MS. BMD at both sites positively correlated with body mass index (BMI), waist circumference (WC) and glucose in unadjusted analysis. In multiple regression analysis, WC was independently associated with BMD at both sites, while hypertension was associated only with lumbar spine BMD.

CONCLUSIONS

In postmenopausal women, MS is associated with increased lumbar spine BMD and this relation is explained mainly by the higher BMI and WC in the MS group.

Vitamin D deficiency in anesthesia department caregivers at the end of winter

BACKGROUND

To test whether the vitamin D status of anesthesia department caregivers practicing at high Northern latitudes is compatible with current recommendations, the 25-hydroxyvitamin D (25(OH)D) levels of caregivers at hospitals in Iceland (64°08' N) and in Wisconsin (43°07' N) were compared at the end of winter.

METHODS

Anesthesia department faculty and resident physicians, non-physician anesthetists, and critical care nurses completed a questionnaire, and provided blood samples for analysis of 25(OH)D by reverse-phase high performance liquid chromatography.

RESULTS

One hundred and six participants in Iceland and 124 participants in Wisconsin were enrolled. No difference in mean serum 25(OH)D levels between Iceland [70.53 nmol/l, standard deviation (SD) 30.87 nmol/l] and Wisconsin (70.0 nmol/l, SD 30.0 nmol/l) was observed. In Iceland and Wisconsin, 25(OH)D levels below 25 nmol/l were observed in 4.7% and 4.0%, below 50 nmol/l in 34.9% and 25.0%, and below 75 nmol/l in 56.6% and 61.3% of caregivers, respectively.

CONCLUSIONS

25(OH)D levels below the 50 nmol/l (20 ng/ml) threshold recommended by the Institute of Medicine and the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis, and below the 75 nmol/l (30 ng/ml) threshold recommended by The Endocrine Society, are highly prevalent among anesthesia caregivers working at two Northern hospitals at the end of winter who may otherwise not meet criteria to be tested. Anesthesia and critical care providers may wish to determine their 25(OH)D levels and use effective, safe, and low cost supplementation to target a 25(OH)D level compatible with optimal health.

Immunoregulatory mechanisms of vitamin D relevant to respiratory health and asthma

Vitamin D deficiency is prevalent among people with various immune-mediated conditions, including autoimmune diseases and asthma. Serum 25(OH)D levels inversely correlate with asthma severity, glucocorticoid responsiveness/dosage, and markers of pathogenesis, such as airway remodeling, IgE, and eosinophilia. Trials involving supplementation with active vitamin D or a precursor are beginning to emerge with variable results that, in part, reflect differences in study design. This review looks at the mechanisms by which vitamin D may protect against asthma, including increasing glucocorticoid responsiveness, skewing immune cells towards a regulatory phenotype, reducing the incidence of infections, airway remodeling, eosinophilia, and lowering the levels of IgE. Also discussed is the therapeutic potential for vitamin D, which is likely to be applicable to immune-mediated conditions beyond simply asthma.

Association between serum 25-hydroxyvitamin D concentration and symptoms of respiratory tract infection in a Norwegian population: the Tromsø Study

OBJECTIVE

Previous studies have suggested anti-infection effects of vitamin D, although the associations reported between vitamin D (serum 25-hydroxyvitamin D (25(OH)D) concentration) and respiratory tract infection (RTI) are conflicting. The main aim of the present study was to explore this association in a Norwegian population.

DESIGN

We examined the association between serum 25(OH)D and recent RTI symptoms in 6350 middle-aged and elderly participants in the Tromsø Study 6. The main outcome measurement was self-reported RTI symptoms in the previous week.

SETTING

Tromsø, Norway, 69 °N.

SUBJECTS

Six thousand three hundred and fifty middle-aged and elderly residents of Tromsø.

RESULTS

Of the 6350 included, 791 (12.5%) reported RTI symptoms in the previous week. We classified serum 25(OH)D concentrations into quartiles and adjusted the data for current smoking habit and month of attendance. The prevalence of RTI symptoms did not increase with decreasing serum 25(OH)D level, was highest in quartile 3 (15.0%) followed by quartile 4 (12.4%), and was lowest in quartiles 1 and 2 (11.1% and 11.4%). There was no trend for increasing duration of illness with decreasing serum 25(OH)D. The prevalence of RTI symptoms was not significantly associated with the intake of fish, n-3 capsules or vitamin and/or mineral supplements, or sun exposure. Only use of cod-liver oil or fish oil capsules daily or sometimes was significantly associated with fewer RTI symptoms during the preceding 7 d (P = 0.04).

CONCLUSIONS

Low serum 25(OH)D was not associated with increased prevalence of recent RTI symptoms. Our findings do not support the idea that vitamin D supplementation can reduce the incidence of RTI in Norway.

Low serum 25-hydroxyvitamin D level and risk of upper respiratory tract infection in children and adolescents

Background. Vitamin D may be important for immune function. Studies to date have shown an inconsistent association between vitamin D and infection with respiratory viruses. The purpose of this study was to determine if serum 25-hydroxyvitamin D (25(OH)D) was associated with laboratory-confirmed viral respiratory tract infections (RTIs) in children.

Methods. Serum 25(OH)D levels were measured at baseline and children from Canadian Hutterite communities were followed prospectively during the respiratory virus season. Nasopharyngeal specimens were obtained if symptoms developed and infections were confirmed using polymerase chain reaction. The association between serum 25(OH)D and time to laboratory-confirmed viral RTI was evaluated using a Cox proportional hazards model.

Results. Seven hundred forty-three children aged 3–15 years were followed between 22 December 2008 and 23 June 2009. The median serum 25(OH)D level was 62.0 nmol/L (interquartile range, 51.0–74.0). A total of 229 participants (31%) developed at least 1 laboratory-confirmed viral RTI. Younger age and lower serum 25(OH)D levels were associated with increased risk of viral RTI. Serum 25(OH)D levels <75 nmol/L increased the risk of viral RTI by 50% (hazard ratio [HR], 1.51; 95% confidence interval [CI], 1.10–2.07, P = .011) and levels <50 nmol/L increased the risk by 70% (HR, 1.67; 95% CI, 1.16–2.40, P = .006).

Conclusions. Lower serum 25(OH)D levels were associated with increased risk of laboratory-confirmed viral RTI in children from Canadian Hutterite communities. Interventional studies evaluating the role of vitamin D supplementation to reduce the burden of viral RTIs are warranted.