Serum 25-Hydroxyvitamin D Values and Risk of All-Cause and Cause-Specific Mortality: A Population-Based Cohort Study

Vitamin D and depression in older adults: lessons learned from observational and clinical studies

Depression is a mental disorder triggered by the interaction of social, psychological and biological factors that have an important impact on an individual's life. Despite being a well-studied disease with several established forms of treatment, its prevalence is increasing, especially among older adults. New forms of treatment and prevention are encouraged, and some researchers have been discussing the effects of vitamin D (VitD) on depression; however, the exact mechanism by which VitD exerts its effects is not yet conclusive. In this study, we aimed to discuss the possible mechanisms underlying the association between VitD and depression in older adults. Therefore, we conducted a systematic search of databases for indexed articles published until 30 April 2021. The primary focus was on both observational studies documenting the association between VitD and depression/depressive symptoms, and clinical trials documenting the effects of VitD supplementation on depression/depressive symptoms, especially in older adults. Based on pre-clinical, clinical and observational studies, it is suggested that the maintenance of adequate VitD concentrations is an important issue, especially in older adults, which are a risk population for both VitD deficiency and depression. Nevertheless, it is necessary to carry out more studies using longitudinal approaches in low- and middle-income countries to develop a strong source of evidence to formulate guidelines and interventions.

Social determinants of serum 25-hydroxyvitamin D concentrations deficiency in older Chilean people

Serum 25-hydroxyvitamin D concentrations deficiency is a growing health problem that affects a significant part of the world's population, with particularly negative consequences in children and older adults. Public health has prioritized healthy aging; thus, an investigation of the social determinants related to deficient and insufficient Serum 25-hydroxyvitamin D concentrations in older adults is needed to contribute to the implementation of comprehensive social programs focused on addressing those conditions adversely affecting the health of this group. This study was conducted using a sample of older adults (age ≥ 65 years, n = 1283) from the National Health Survey (NHS 2016-2017). The Average Marginal Effects of the social determinants of Serum 25-hydroxyvitamin D concentrations deficiency in older adults were predicted using a probit model in which the outcome variable assumed two values (deficiency or not deficiency), taking as independent variables those reported in previous studies. The model showed an adequate goodness of fit, Count R2 = 0.65, and the independent variables explained between 11% (Cox-Snell) and 14% (Nagelkerke) of the variance of the outcome variable. The social determinants associated with a greater likelihood of Serum 25-hydroxyvitamin D concentrations deficiency are the following conditions: women, people of native origin, urban dwellers, shorter sunlight exposure, and greater geographical latitude. Implications are discussed, and limitations are considered. Promotion and prevention programs should preferentially target older adults in the southernmost regions who live in urban areas, with a special focus on women. Due to the country's characteristics (17°-57° south latitude), it is necessary to review in future research the three zones shown in this study as relevant social determinants for the older adults living in them to generate inputs in formulating public health policies. The authorities must define the cut-off points for considering the difference between the country's ranges of Serum 25-hydroxyvitamin D concentrations insufficiency and deficiency.

Infections and Autoimmunity-The Immune System and Vitamin D: A Systematic Review

Both 25-autoimmunity and(25(OH)D: calcifediol) and its active form, 1,25-dihydroxyvitamin D (1,25(OH)2D: calcitriol), play critical roles in protecting humans from invasive pathogens, reducing risks of autoimmunity, and maintaining health. Conversely, low 25(OH)D status increases susceptibility to infections and developing autoimmunity. This systematic review examines vitamin D's mechanisms and effects on enhancing innate and acquired immunity against microbes and preventing autoimmunity. The study evaluated the quality of evidence regarding biology, physiology, and aspects of human health on vitamin D related to infections and autoimmunity in peer-reviewed journal articles published in English. The search and analyses followed PRISMA guidelines. Data strongly suggested that maintaining serum 25(OH)D concentrations of more than 50 ng/mL is associated with significant risk reduction from viral and bacterial infections, sepsis, and autoimmunity. Most adequately powered, well-designed, randomized controlled trials with sufficient duration supported substantial benefits of vitamin D. Virtually all studies that failed to conclude benefits or were ambiguous had major study design errors. Treatment of vitamin D deficiency costs less than 0.01% of the cost of investigation of worsening comorbidities associated with hypovitaminosis D. Despite cost-benefits, the prevalence of vitamin D deficiency remains high worldwide. This was clear among those who died from COVID-19 in 2020/21-most had severe vitamin D deficiency. Yet, the lack of direction from health agencies and insurance companies on using vitamin D as an adjunct therapy is astonishing. Data confirmed that keeping an individual's serum 25(OH)D concentrations above 50 ng/mL (125 nmol/L) (and above 40 ng/mL in the population) reduces risks from community outbreaks, sepsis, and autoimmune disorders. Maintaining such concentrations in 97.5% of people is achievable through daily safe sun exposure (except in countries far from the equator during winter) or taking between 5000 and 8000 IU vitamin D supplements daily (average dose, for non-obese adults, ~70 to 90 IU/kg body weight). Those with gastrointestinal malabsorption, obesity, or on medications that increase the catabolism of vitamin D and a few other specific disorders require much higher intake. This systematic review evaluates non-classical actions of vitamin D, with particular emphasis on infection and autoimmunity related to the immune system.

Association of serum 25-hydroxyvitamin D with the incidence of 16 cancers, cancer mortality, and all-cause mortality among individuals with metabolic syndrome: a prospective cohort study

PURPOSE

The relationship between vitamin D levels and cancer incidence and mortality in individuals with metabolic syndrome (MetS) remains poorly explored. Herein, we aimed to determine the association between 25-hydroxyvitamin D [25(OH)D] concentrations and the risk of 16 cancer incidence types and cancer/all-cause mortality in patients with MetS.

METHODS

We enrolled 97,621 participants with MetS at recruitment from the UK Biobank cohort. The exposure factor was baseline serum 25(OH)D concentrations. The associations were examined using Cox proportional hazards models, which were displayed as hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

Over a median follow-up period of 10.92 years for cancer incidence outcomes, 12,137 new cancer cases were recorded. We observed that 25(OH)D concentrations were inversely related to the risk of colon, lung, and kidney cancer, and HRs (95% CI) for 25(OH)D ≥ 75.0 vs. < 25.0 nmol/L were 0.67 (0.45-0.98), 0.64 (0.45-0.91), and 0.54 (0.31-0.95), respectively. The fully adjusted model revealed a null correlation between 25(OH)D and the incidence of stomach, rectum, liver, pancreas, breast, ovary, bladder, brain, multiple myeloma, leukemia, non-Hodgkin lymphoma, esophagus, and corpus uteri cancer. Over a median follow-up period of 12.72 years for mortality outcomes, 8286 fatalities (including 3210 cancer mortalities) were documented. An "L-shaped" nonlinear dose-response correlation was detected between 25(OH)D and cancer/all-cause mortality; the respective HRs (95% CI) were 0.75 (0.64-0.89) and 0.65 (0.58-0.72).

CONCLUSION

These findings emphasize the importance of 25(OH)D in cancer prevention and longevity promotion among patients with MetS.

Vitamin D in Depression: A Potential Bioactive Agent to Reduce Suicide and Suicide Attempt Risk

Suicide is one of the leading causes of death worldwide. According to the World Health Organization (WHO), every year, more than 700 thousand people die from this cause. Therefore, suicide is a public health issue. The complex interaction between different factors causes suicide; however, depression is one of the most frequent factors in people who have attempted suicide. Several studies have reported that vitamin D deficiency may be a relevant risk factor for depression, and vitamin D supplementation has shown promising effects in the adjunctive treatment of this mood disorder. Among the beneficial mechanisms of vitamin D, it has been proposed that it may enhance serotonin synthesis and modulate proinflammatory cytokines since low serotonin levels and systemic inflammation have been associated with depression and suicide. The present narrative review shows the potential pathogenic role of vitamin D deficiency in depression and suicide and the potential benefits of vitamin D supplementation to reduce their risk.

Adiposity and physical activity are among the main determinants of serum vitamin D concentrations in older adults: the EpiFloripa Aging Cohort Study

The identification of factors associated with 25-hydroxycholecalciferol (25(OH)D) concentration can help suggest more specific interventions for older adults. In this cross-sectional study of older adults from southern Brazil, we hypothesized that some sociodemographic, behavioral, and health factors positively or negatively influence the 25(OH)D concentration in this population. This analysis was performed using data from the second wave of the EpiFloripa Aging Cohort Study (2013-2015). Serum 25(OH)D levels were classified according to the guidelines of the Endocrine Society. Multinomial logistic regression was performed to evaluate the relative risks of sociodemographic, behavioral, and health factors in each 25(OH)D category. A total of 574 older adults (aged 63-93 years) participated in this study. The prevalence of insufficiency (21-29 ng/mL) was 43.7% and that of deficiency (≤20 ng/mL) was 23.5%. In the adjusted analysis, female sex, higher levels of low-density lipoprotein cholesterol (LDL-C ≥160 mg/dL), obesity by adiposity (body fat percentage [%fat], male ≥31%; female ≥43%), and body mass index (BMI, >30 kg/m²) presented higher relative risks for insufficiency than for sufficiency. For those with deficiency, the associated factors were female sex, disability in 4 or more activities of daily living (ADLs), LDL-C ≥100 mg/dL, and obesity by %fat and BMI. A protective factor against insufficiency and deficiency was active leisure-time physical activity (PA, ≥150 min/week). Our results demonstrated that being female and having modifiable factors, such as high levels of LDL-C, obesity, and disability on ADLs, were negatively associated with hypovitaminosis D. On the other hand, leisure-time PA was positively associated with adequate serum vitamin D concentration.

Serum 25-Hydroxyvitamin D concentrations are inversely associated with all-cause mortality among Koreans: a nationwide cohort study

Evidence on the association between serum 25-hydroxyvitamin D (25(OH)D) concentration and all-cause and cause-specific mortality in Asians, especially Koreans, is limited. We hypothesized that high concentrations of 25(OH)D are associated with lower all-cause and cause-specific mortality in the general Korean population. This study included 27,846 adults participating in the Fourth and Fifth Korean National Health and Nutrition Examination Survey 2008-2012, followed up through December 31, 2019. Hazard ratios (HR) and 95% confidence intervals (CIs) for mortality from all causes, cardiovascular disease (CVD), and cancer were estimated using multivariable-adjusted Cox proportional hazards regression. The weighted mean serum 25(OH)D of study participants was 17.77 ng/mL; 66.5% had vitamin D deficiency (<20 ng/mL) and 94.2% had insufficient vitamin D (<30 ng/mL). During a median follow-up of 9.4 years (interquartile range, 8.1-10.6 years), 1680 deaths were documented, including 362 CVD deaths and 570 cancer deaths. Serum 25(OH)D levels ≥30 ng/mL were inversely associated with all-cause mortality (HR, 0.57; 95% CI, 0.43-0.75) compared with serum 25(OH)D levels <10 ng/mL. Based on the quartile cutoffs of serum 25(OH)D concentration, the highest quartile of serum 25(OH)D concentration (≥21.8 ng/mL) was associated with the lowest all-cause mortality (HR, 0.72; 95% CI, 0.60-0.85; P trend < .001), and CVD mortality (HR, 0.60; 95% CI, 0.42-0.85; P trend = .006). No association with cancer mortality outcome was found. In conclusion, higher serum 25(OH)D levels were associated with lower all-cause mortality in the general Korean population. An additional association was found between higher quartile of serum 25(OH)D and lower CVD mortality.

Association between lower serum vitamin D (25-hydroxy-cholecalciferol) concentrations and cognitive impairment in older adults: data from a populational-based cohort study in a middle-income country

OBJECTIVE

To investigate the association between serum vitamin D (25-hydroxy-cholecalciferol) (25(OH)D) concentrations and cognitive impairment in older adults living in Southern Brazil.

DESIGN

Cross-sectional analysis using data from the second follow-up wave of the populational-based EpiFloripa Aging Cohort Study was collected in 2013-2014.

SETTING

Cognitive impairment was evaluated using the Mini-Mental State Examination (MMSE). Blood samples were collected to measure serum vitamin D concentrations using a chemiluminescent microparticle immunoassay. Vitamin D concentrations were distributed in quartiles (Q1: 4·0-20·7 ng/ml; Q2: 20·8-26·6 ng/ml; Q3: 26·7-32·0 ng/ml and Q4: 32·1-60·1 ng/ml), and its association with cognitive impairment was tested by crude and adjusted logistic regression (sociodemographic, behavioural and health aspects) using Q4 as a reference group.

PARTICIPANTS

200 men and 371 women aged 60 years or older participated in this study.

RESULTS

The prevalence of probable cognitive impairment was 21·7 %. Those without cognitive impairment had a higher mean of vitamin D serum concentrations (26·8 v. 24·6, P = 0·014). In the crude analysis, only individuals in Q2 of vitamin D presented an increased risk for probable cognitive impairment compared with Q4 (highest quartile) (OR 2·65, 95 % CI 1·46, 4·81), remaining significant in the adjusted analysis (OR 6·04, 95 % CI 2·78, 13·13). While Q1 (lowest quartile) was not associated in the crude analysis, but when adjusted, an increased risk of cognitive impairment was observed.

CONCLUSION

The lowest quartile of vitamin D was directly associated with probable cognitive impairment in older adults in Southern Brazil. More studies are needed to investigate whether maintaining adequate serum levels may represent a significant factor in preventing age-related neurological disorders as well as to verify the need for new cutoff points for this age group.

Vitamin D prescribing practices among clinical practitioners during the COVID‐19 pandemic

Background and Aims

COVID‐19 has caused devastation globally. Low vitamin D status, particularly during the winter months, remains commonplace around the world, and it is thought to be one of the contributing factors toward causation and severity of COVID‐19. Many guidelines do not recommend vitamin D for the treatment or prevention of the disease. Hence, we set out to conduct a global survey to understand the use and prescribing habits of vitamin D among clinicians for COVID‐19.

Methods

An online anonymous questionnaire was sent to clinicians enquiring about their prescribing habits of vitamin D and personal use of vitamin D. Data of the survey were collected between January 15, 2021, and February 13, 2021.

Results

Four thousand four hundred forty practicing clinicians were included in the analysis, with the majority of those responding from Asia, followed by Europe. 82.9% prescribed vitamin D before COVID‐19, more commonly among general practitioners (GPs) in comparison with medical specialists, and Asian clinicians were more likely to prescribe vitamin D in comparison with Caucasian physicians (p < 0.01). GPs were also more likely to prescribe vitamin D prophylactically to prevent COVID‐19 in comparison with medical specialists (OR 1.47, p < 0.01). Most GPs (72.8%) would also prescribe vitamin D to treat COVID‐19 in comparison with medical specialists (OR 1.81, p < 0.01), as well as more Asian in comparison with Caucasian physicians (OR 4.57, p < 0.01). 80.4% of respondents were taking vitamin D, more so in the 45–54 and 65–74 age groups in comparison with the 18–24 years category (OR 2.15 and 2.40, respectively, both p < 0.05), many of whom did so before COVID‐19 (72.1%).

Conclusion

This survey has shown that many clinicians would prescribe vitamin D for the prevention and treatment of COVID‐19. The majority would also recommend measuring vitamin D levels, but not so in patients with COVID‐19.

Comparison of Two Strategies to Increase Serum Vitamin D Levels in a Real-World Setting: Sunlight Exposure and Oral Supplementation

Sunlight exposure and oral supplementation are the key strategies to increase serum 25-hydroxyvitamin D [25(OH)D] concentration. We aimed to determine elevation in serum 25(OH)D levels by comparing sunlight exposure and oral vitamin D supplementation in vitamin D-deficient participants who chose the treatment strategy by shared decision-making. We enrolled 197 participants aged ≥19 y who had vitamin D deficiency (serum 25(OH)D<20 ng/mL). Participants selected their treatment method through shared decision-making by preference: sunlight exposure or 1,000 IU oral vitamin D3 supplementation daily. Changes in serum 25(OH)D concentration and duration of sunlight exposure were evaluated after 3 mo. Among 197 participants, 26 (13%) selected sunlight exposure and 171 (87%) selected oral vitamin D supplementation. Seasonal distribution of participants and follow-up rate after 3 mo were not significantly different. There was no significant increase in mean serum 25(OH)D levels in the sunlight exposure group. Conversely, the mean serum 25(OH)D level increased by 11 ng/mL after 3 mo in the oral vitamin D supplementation group. The duration of mean sunlight exposure per day during the study period was not significantly different between the groups. Oral supplementation with 1,000 IU vitamin D3 daily significantly increased serum 25(OH)D levels in vitamin D-deficient participants after 3 mo, while sunlight exposure did not. This study suggests that oral supplementation is more effective than sun exposure in increasing vitamin D levels in the Korean population. Therefore, new recommendations on maintaining adequate vitamin D levels are needed in the Korean population.

Vitamin D and Rheumatic Diseases: A Review of Clinical Evidence

Vitamin D plays an important role in maintaining a healthy mineralized skeleton. It is also considered an immunomodulatory agent that regulates innate and adaptive immune systems. The aim of this narrative review is to provide general concepts of vitamin D for the skeletal and immune health, and to summarize the mechanistic, epidemiological, and clinical evidence on the relationship between vitamin D and rheumatic diseases. Multiple observational studies have demonstrated the association between a low level of serum 25-hydroxyvitamin D [25(OH)D] and the presence and severity of several rheumatic diseases, such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), spondyloarthropathies, and osteoarthritis (OA). Nevertheless, the specific benefits of vitamin D supplements for the treatment and prevention of rheumatic diseases are less accepted as the results from randomized clinical trials are inconsistent, although some conceivable benefits of vitamin D for the improvement of disease activity of RA, SLE, and OA have been demonstrated in meta-analyses. It is also possible that some individuals might benefit from vitamin D differently than others, as inter-individual difference in responsiveness to vitamin D supplementation has been observed in genomic studies. Although the optimal level of serum 25(OH)D is still debatable, it is advisable it is advisable that patients with rheumatic diseases should maintain a serum 25(OH)D level of at least 30 ng/mL (75 nmol/L) to prevent osteomalacia, secondary osteoporosis, and fracture, and possibly 40–60 ng/mL (100–150 nmol/L) to achieve maximal benefit from vitamin D for immune health and overall health.

Serum 25-hydroxyvitamin D values and risk of incident cardiovascular disease: A population-based retrospective cohort study

BACKGROUND

Concentrations of serum 25-hydroxyvitamin D [25(OH)D] below 20 ng/mL and above 50 ng/mL have been associated with chronic adverse events including cardiovascular disease.

OBJECTIVE

To conduct a comprehensive population-based study in the United States of the relationship of low and high serum 25(OH)D levels with cardiovascular disease.

METHODS

We identified all serum 25(OH)D measurements in adults age 18 years and older residing in Olmsted County, MN between January 1, 2005 and December 31, 2011, using the resources of the Rochester Epidemiology Project. Any new diagnosis of cardiovascular disease was the primary outcome, and time zero was 30 days after first 25(OH)D measurement. Patients were followed until their last clinical visit as an Olmsted County resident, December 31, 2014, or death. Categories of 25(OH)D values were examined using predetermined ranges of interest: <12, 12-19, 20-50 (reference range), and >50 ng/mL. Multivariable Cox proportional hazards models were adjusted for age, BMI, sex, race, smoking history, season of 25(OH)D measurement, hypertension, hyperlipidemia, socioeconomic status and Charlson comorbidity index at time of 25(OH)D measurement.

RESULTS

A total of 11,002 unique persons had a 25(OH)D measurement, with a mean (±SD) value of 30.0 ± 12.9 ng/mL. Mean age was 54.3 ± 17.2 years, and the majority were female (77.1 %) and white (87.6 %). There were 4124 new diagnoses of cardiovascular disease in this cohort after a median overall follow-up of 4.8 years (IQR 3.4-6.2). Adjusted cardiovascular disease hazard ratios (HRs) (95 % confidence interval) for 25(OH)D values <12, 12-19, and >50 ng/mL, compared to the reference range 20-50 ng/mL, were 1.28 (1.12-1.46), 1.19 (1.09-1.31), and 1.10 (0.95-1.26), respectively.

CONCLUSION

Values of 25(OH)D <20 ng/mL were associated with development of a new diagnosis of cardiovascular disease. There was no significant association between 25(OH)D values >50 ng/mL and cardiovascular disease.

Association Between Serum 25-hydroxyvitamin D Concentrations and Mortality Among Adults With Prediabetes

OBJECTIVES

To investigate the association of circulating 25-hydroxyvitamin D [25(OH)D] levels with mortality among adults with prediabetes.

METHODS

This retrospective cohort study included 15,195 adults with prediabetes (aged ≥20 years) from the National Health and Nutrition Examination Survey (NHANES) III and NHANES 2001-2014. Mortality from all causes, cardiovascular disease (CVD), and cancer was linked to National Death Index mortality data.

RESULTS

The median (interquartile range) concentration of serum 25(OH)D was 60.5 (45.3, 77.4) nmol/L, and only 23.1% had sufficient vitamin D (≥75 nmol/L). Elevated serum 25(OH)D concentrations were significantly associated with lower levels of insulin, homeostasis model assessment of insulin resistance, triglyceride, and C-reactive protein, and higher levels of high-density lipoprotein at baseline (all Ptrend < 0.05). During a median follow up of 10.7 years, 3765 deaths (including 1080 CVD deaths and 863 cancer deaths) were identified. Compared with participants with 25(OH)D <30 nmol/L, the multivariate-adjusted hazard ratios and 95% confidence intervals for participants with 25(OH)D ≥ 75 nmol/L were 0.66 (0.53, 0.82) for all-cause mortality (Ptrend < 0.001), 0.66 (0.48, 0.89) for CVD mortality (Ptrend = 0.001), and 0.82 (0.49, 1.35) for cancer mortality (Ptrend = 0.32). For per-unit increment in ln-transformed 25(OH)D, there was a 27% lower risk of all-cause mortality and a 34% lower risk of CVD mortality (both P < 0.01).

CONCLUSIONS

These findings suggested that higher serum 25(OH)D concentrations were associated with lower all-cause and CVD mortality among individuals with prediabetes.

Serum 25-Hydroxyvitamin D and Subsequent Cancer Incidence and Mortality: A Population-Based Retrospective Cohort Study

OBJECTIVE

To determine the relationship between 25-hydroxyvitamin D (25[OH]D) values and subsequent cancer incidence and mortality.

PATIENTS AND METHODS

We identified all adult patients living in Olmsted County, Minnesota, between January 1, 2005, and December 31, 2011, who had at least 1 25(OH)D measurement and no prior diagnosis of cancer. Cancer outcomes were retrieved starting 30 days after 25(OH)D measurement and until patients' final clinical visit as an Olmsted County resident; December 31, 2014; or death. Cox proportional hazards regression was used to analyze data.

RESULTS

A total of 8700 individuals had a 25(OH)D measurement and no history of cancer, with a mean ± SD 25(OH)D value of 29.7±12.8 ng/mL (to convert to nmol/L, multiply by 2.496). The mean ± SD age was 51.5±16.4 years, and most were women (78.1%; n=6796) and White (85.7%; n=7460). A total of 761 individuals developed cancer (skin cancer, n=360; nonskin cancer, n=401) during a median follow-up of 4.6 (interquartile range, 3.4-6.1) years. Compared with participants with 25(OH)D values of 20 to 50 ng/mL (reference group), those with 25(OH)D values less than 12 ng/mL had a greater nonskin cancer incidence (hazard ratio [HR], 1.56; 95% CI, 1.03 to 2.36; P=.04) after adjustment. There was no association between 25(OH)D values and total cancer or skin cancer incidence. Compared with individuals from the reference group, 25(OH)D levels less than 12 ng/mL (HR, 2.35; 95% CI, 1.01 to 5.48; P=.047) and 12 to 19 ng/mL (HR, 2.10; 95% CI, 1.05 to 4.22; P=.04) were associated with increased cancer mortality.

CONCLUSION

Low 25(OH)D levels were associated with increased risk for incident nonskin cancer and cancer-related mortality.

Oral and Topical Vitamin D, Sunshine, and UVB Phototherapy Safely Control Psoriasis in Patients with Normal Pretreatment Serum 25-Hydroxyvitamin D Concentrations: A Literature Review and Discussion of Health Implications

Vitamin D, sunshine and UVB phototherapy were first reported in the early 1900s to control psoriasis, cure rickets and cure tuberculosis (TB). Vitamin D also controlled asthma and rheumatoid arthritis with intakes ranging from 60,000 to 600,000 International Units (IU)/day. In the 1980s, interest in treating psoriasis with vitamin D rekindled. Since 1985 four different oral forms of vitamin D (D2, D3, 1-hydroxyvitaminD3 (1(OH)D3) and 1,25-dihydroxyvitaminD3 (calcitriol)) and several topical formulations have been reported safe and effective treatments for psoriasis-as has UVB phototherapy and sunshine. In this review we show that many pre-treatment serum 25(OH)D concentrations fall within the current range of normal, while many post-treatment concentrations fall outside the upper limit of this normal (100 ng/mL). Yet, psoriasis patients showed significant clinical improvement without complications using these treatments. Current estimates of vitamin D sufficiency appear to underestimate serum 25(OH)D concentrations required for optimal health in psoriasis patients, while concentrations associated with adverse events appear to be much higher than current estimates of safe serum 25(OH)D concentrations. Based on these observations, the therapeutic index for vitamin D needs to be reexamined in the treatment of psoriasis and other diseases strongly linked to vitamin D deficiency, including COVID-19 infections, which may also improve safely with sufficient vitamin D intake or UVB exposure.

Vitamin D and Its Potential Benefit for the COVID-19 Pandemic

Vitamin D is known not only for its importance for bone health but also for its biologic activities on many other organ systems. This is due to the presence of the vitamin D receptor in various types of cells and tissues, including the skin, skeletal muscle, adipose tissue, endocrine pancreas, immune cells, and blood vessels. Experimental studies have shown that vitamin D exerts several actions that are thought to be protective against coronavirus disease (COVID-19) infectivity and severity. These include the immunomodulatory effects on the innate and adaptive immune systems, the regulatory effects on the renin-angiotensin-aldosterone-system in the kidneys and the lungs, and the protective effects against endothelial dysfunction and thrombosis. Prior to the COVID-19 pandemic, studies have shown that vitamin D supplementation is beneficial in protecting against risk of acquiring acute respiratory viral infection and may improve outcomes in sepsis and critically ill patients. There are a growing number of data connecting COVID-19 infectivity and severity with vitamin D status, suggesting a potential benefit of vitamin D supplementation for primary prevention or as an adjunctive treatment of COVID-19. Although the results from most ongoing randomized clinical trials aiming to prove the benefit of vitamin D supplementation for these purposes are still pending, there is no downside to increasing vitamin D intake and having sensible sunlight exposure to maintain serum 25-hydroxyvitamin D at a level of least 30 ng/mL (75 nmol/L) and preferably 40 to 60 ng/mL (100-150 nmol/L) to minimize the risk of COVID-19 infection and its severity.

The VITamin D and OmegA-3 TriaL (VITAL): Do Results Differ by Sex or Race/Ethnicity?

Whether vitamin D or marine omega-3 (n-3) fatty acid supplementation reduces risk of cancer or cardiovascular disease (CVD) in general populations at usual risk for these outcomes is relatively unexplored in randomized trials. The primary goal of the VITamin D and OmegA-3 TriaL (VITAL), a nationwide, randomized, placebo-controlled, 2 × 2 factorial trial of vitamin D₃ (2000 IU/day) and marine n-3 fatty acids (1 g/day) in the primary prevention of cancer and CVD among 25 871 US men aged ≥50 years and women aged ≥55 years, was to fill these knowledge gaps. Studying the influence of sex and race/ethnicity on treatment-related outcomes was a prespecified goal; such analyses help ensure that important effects are not missed and contribute to the foundation for developing targeted recommendations for supplement use. To enable investigation of potential sex- and race-specific treatment effects, trial investigators enrolled an even balance of men (n = 12 786) and women (n = 13 085) and oversampled African Americans (n = 5106). Significant or suggestive variation in intervention effects according to sex, race/ethnicity, and other participant characteristics was observed for some, though not all, outcomes. Additional research is needed to determine which individuals may be most likely to derive a net benefit from vitamin D or n-3 fatty acid supplementation. (VITAL clinicaltrials.gov identifier: NCT01169259).

Serum vitamin D levels in healthy urban population at reproductive age: effects of age, gender and season

OBJECTIVE

The aim of the study was to determine the effects of age, gender and season on vitamin D status in healthy urban population at reproductive age. Also, we investigated the distribution of population into different groups regarding 25(OH)D levels.

METHODS

Serum 25(OH)D levels of 21,317 participants: 5,364 men (25.1%) and 15,953 women (74.8%), aged between 18-45 years, applying to two medical centres for check-up located in the same city were retrospectively analyzed. Group I consisted of 14,720 participants (11,257 women and 3,463 men) in the first centre and Group II consisted of 6,597 participants (4,696 women and 1,901 men) in the second centre.

RESULTS

The mean 25(OH)D levels did not differ between women and men in both groups: 23.4 (SD = 14.4) and 23.1 (SD = 12.6) in Group I, and 22.6 (SD = 15.9) and 23.1 (SD = 14.3) in Group II, respectively, (p > 0.05). Similar trends exhibiting lower mean 25(OH)D levels at younger ages and higher levels at later ages were observed in both groups; a seasonal variation of 25(OH)D levels was observed in both genders with the highest levels in August and September and the lowest levels from February through April; percentages of women with 25(OH)D level of < 5 ng/ml were significantly higher than of men in Group I (1.4% vs. 0.2%, respectively, p < 0.001) and in Group II (4.1% vs. 1.1%, respectively, p < 0.001).

CONCLUSION

There is a slight increase in serum 25(OH)D levels from 18 through 45 years of age in healthy population. The seasonal variation of 25(OH)D levels is prominent in both genders with men having slightly lower levels in some months of winter and higher levels in summer as compared to women. The prevalence of women having 25(OH)D levels less than 5 ng/ml is higher than that of men.

Immunologic Effects of Vitamin D on Human Health and Disease

Vitamin D is responsible for regulation of calcium and phosphate metabolism and maintaining a healthy mineralized skeleton. It is also known as an immunomodulatory hormone. Experimental studies have shown that 1,25-dihydroxyvitamin D, the active form of vitamin D, exerts immunologic activities on multiple components of the innate and adaptive immune system as well as endothelial membrane stability. Association between low levels of serum 25-hydroxyvitamin D and increased risk of developing several immune-related diseases and disorders, including psoriasis, type 1 diabetes, multiple sclerosis, rheumatoid arthritis, tuberculosis, sepsis, respiratory infection, and COVID-19, has been observed. Accordingly, a number of clinical trials aiming to determine the efficacy of administration of vitamin D and its metabolites for treatment of these diseases have been conducted with variable outcomes. Interestingly, recent evidence suggests that some individuals might benefit from vitamin D more or less than others as high inter-individual difference in broad gene expression in human peripheral blood mononuclear cells in response to vitamin D supplementation has been observed. Although it is still debatable what level of serum 25-hydroxyvitamin D is optimal, it is advisable to increase vitamin D intake and have sensible sunlight exposure to maintain serum 25-hydroxyvitamin D at least 30 ng/mL (75 nmol/L), and preferably at 40-60 ng/mL (100-150 nmol/L) to achieve the optimal overall health benefits of vitamin D.

Low Vitamin D Levels Predict Mortality in Ankylosing Spondylitis Patients: A Nationwide Population-Based Cohort Study

In this study, we aimed to examine the effect of vitamin D deficiency on all-cause mortality in ankylosing spondylitis (AS) patients and in the general population. This is a retrospective-cohort study based on the electronic database of the largest health-maintenance organization in Israel. AS patients who were first diagnosed between 2002–2007 were included. Controls were matched by age, gender and enrollment-time. Follow-up continued until death or end of study follow-up on 1 July 2019. Laboratory measures of serum 25-hydroxyvitamin-D levels during the entire follow-up period were obtained. A total of 919 AS patients and 4519 controls with a mean time of follow-up of 14.3 years were included. The mean age at the time of enrollment was 52 years, and 22% of them were females. AS was associated with a higher proportion of vitamin D deficiency (odds ratio 1.27 [95% confidence-interval (CI) 1.03–1.58]). In AS patients, insufficient levels of vitamin D (<30 ng/mL) were significantly associated with increased incidence of all-cause mortality (hazard ratio (HR) 1.59 [95% CI 1.02–2.50]). This association was more prominent with the decrease in vitamin D levels (< 20 ng/mL, HR 1.63 [95% CI 1.03–2.60]; <10 ng/mL, HR 1.79 [95% CI 1.01–3.20]) and among male patients (<30 ng/mL, HR 2.11 [95% CI 1.20–3.72]; <20 ng/mL, HR 2.12 [95% CI 1.19–3.80]; <10 ng/mL, HR 2.23 [95% CI 1.12–4.43]). However, inadequate levels of vitamin D among controls were not associated with an increased all-cause mortality. Our study has shown that vitamin D deficiency is more common in AS patients than controls and is linked to an increased risk for all-cause mortality. These results emphasize the need for randomized-controlled trials to evaluate the benefits of vitamin D supplementation as a secondary prevention of mortality in patients with chronic inflammatory rheumatic disease.

Circulating 25-hydroxyvitamin D concentration and cause-specific mortality in the Melbourne Collaborative Cohort Study

Vitamin D deficiency is associated with higher all-cause mortality, but associations with specific causes of death are unclear. We investigated the association between circulating 25-hydroxyvitamin D (25(OH)D) concentration and cause-specific mortality using a case-cohort study within the Melbourne Collaborative Cohort Study (MCCS). Eligibility for the case-cohort study was restricted to participants with baseline dried blood spot samples and no pre-baseline diagnosis of cancer. These analyses included participants who died (n = 2307) during a mean follow-up of 14 years and a sex-stratified random sample of eligible cohort participants ('subcohort', n = 2923). Concentration of 25(OH)D was measured using liquid chromatography-tandem mass spectrometry. Cox regression, with Barlow weights and robust standard errors to account for the case-cohort design, was used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for cause-specific mortality in relation to 25(OH)D concentration with adjustment for confounders. Circulating 25(OH)D concentration was inversely associated with risk of death due to cancer (HR per 25 nmol/L increment = 0.88, 95 % CI 0.78-0.99), particularly colorectal cancer (HR = 0.75, 95 % CI 0.57-0.99). Higher 25(OH)D concentrations were also associated with a lower risk of death due to diseases of the respiratory system (HR = 0.62, 95 % CI 0.43-0.88), particularly chronic obstructive pulmonary disease (HR = 0.53, 95 % CI 0.30-0.94), and diseases of the digestive system (HR = 0.44, 95 % CI 0.26-0.76). Estimates for diabetes mortality (HR = 0.64, 95 % CI 0.33-1.26) and cardiovascular disease mortality (HR = 0.90, 95 % CI 0.76-1.07) lacked precision. The findings suggest that vitamin D might be important for preventing death due to some cancers, respiratory diseases, and digestive diseases.

Principal results of the VITamin D and OmegA-3 TriaL (VITAL) and updated meta-analyses of relevant vitamin D trials

Whether supplemental vitamin D reduces risk of cancer or cardiovascular disease (CVD) is relatively unexplored in randomized trial settings. The VITamin D and OmegA-3 TriaL (VITAL) was a nationwide, randomized, placebo-controlled, 2 × 2 factorial trial of daily vitamin D₃ (2000 IU) and marine omega-3 fatty acids (1 g) in the primary prevention of cancer and CVD among 25,871 U.S. men aged ≥50 and women aged ≥55, including 5106 African Americans. Median treatment duration was 5.3 years. Vitamin D did not significantly reduce the primary endpoint of total invasive cancer incidence (hazard ratio [HR] = 0.96 [95% confidence interval 0.88-1.06]) but showed a promising signal for reduction in total cancer mortality (HR = 0.83 [0.67-1.02]), especially in analyses that accounted for latency by excluding the first year (HR = 0.79 [0.63-0.99]) or first 2 years (HR = 0.75 [0.59-0.96]) of follow-up. Vitamin D did not significantly reduce the co-primary endpoint of major CVD events (HR = 0.97 [0.85-1.12]), other cardiovascular endpoints, or all-cause mortality (HR = 0.99 [0.87-1.12]). Updated meta-analyses that include VITAL and other recent vitamin D trials indicate a significant reduction in cancer mortality but not in cancer incidence or CVD endpoints. Additional research is needed to determine which individuals may be most likely to derive a net benefit from vitamin D supplementation. (VITAL clinicaltrials.gov identifier: NCT01169259).

The relationship of 25-hydroxyvitamin D concentrations and individual-level socioeconomic status

Socioeconomic status (SES), defined as the ability to access desired resources, is associated with behaviors that may affect vitamin D status. Most studies of the effect of vitamin D status on outcomes do not account for individual-level SES. The ability to adjust for SES in epidemiologic studies, when data on conventional SES measures have not been obtained, would be advantageous. We identified all serum 25(OH)D measurements in adults age 18 years and older residing in Olmsted County, MN, a mixed urban-rural setting, between January 1, 2005 and December 31, 2011, through the Rochester Epidemiology Project. The first 25(OH)D measurement was considered the index measurement for each subject. SES was determined for each subject by the HOUsing-based SocioEconomic Status (HOUSES) index, derived from real property data. The HOUSES index is an aggregated z-score of assessed housing value, area of living space, number of bedrooms, and number of bathrooms, with higher scores indicating higher SES. Multivariable analyses were adjusted for age, BMI, sex, race, season of 25(OH)D measurement, and Charlson comorbidity index. HOUSES was matched for 10,378 of 11,002 subjects (94 %) with 25(OH)D measurements available. The mean (SD) age was 54.3 (17.1) years with 26.9 % ≥65 years; 77.3 % were women, and 12.1 % were non-white. The mean 25(OH)D concentration was 30.0 (12.9) ng/mL, and 598 (5.8 %) had a 25(OH)D value <12 ng/mL. The mean (SD) HOUSES was -1.55 (3.09),-0.97 (3.34), 0.14 (3.52), 0.24 (3.51) for serum 25(OH)D categories of <12, 12-19, 20-50, and >50 ng/mL, respectively (P = 0.12 for trend). 25(OH)D increased by 0.43 (95 % CI 0.36-0.50) ng/mL for each unit increase in HOUSES in univariate analysis and by 0.28 (0.21-0.35; P < 0.001) ng/mL in multivariable analysis. This represents a change of 4 ng/mL across the entire range of observed HOUSES, an effect similar in magnitude to the seasonal variation of 25(OH)D values. SES was independently associated with serum 25(OH)D concentrations in a dose-response manner after adjustment for important covariates. HOUSES is a useful tool to assess the role of individual-level SES in health outcomes when other SES measures are unavailable and to control for confounding by SES in examining the effect of 25(OH)D on clinical and metabolic outcomes.

The ongoing D-lemma of vitamin D supplementation for nonskeletal health and bone health

PURPOSE OF REVIEW

The goal of this review is to give some perspective on the results and conclusions of three recent randomized controlled vitamin D intervention studies that have challenged the health benefit of vitamin D supplementation for reducing risk for cardiovascular disease, cancer, all-cause mortality and type 2 diabetes and improving bone health.

RECENT FINDINGS

Vitamin D supplementation to adults who were vitamin D sufficient or insufficient did not reduce risk for developing cardiovascular disease, cancer, type 2 diabetes nor increases bone mineral density (BMD). Patients who were vitamin D deficient with cancer and received vitamin D reduced risk for mortality by 25% and prediabetic adults who were vitamin D deficient and received vitamin D reduced their risk of developing type 2 diabetes by 62%. Older adults receiving 4000 and 10 000 IUs of vitamin D3 daily for 3 years had reduced radial BMD but had no change in either total hip areal bone density or bone strength in the radius and tibia.

SUMMARY

Caution is needed when evaluating results and conclusions from randomized controlled trials that investigate health benefits of vitamin D; most studies suggest health benefits when vitamin D supplementation is provided to vitamin D deficient populations and little benefit when given to populations that are vitamin D sufficient/insufficient.

Disassociation of Vitamin D's Calcemic Activity and Non-calcemic Genomic Activity and Individual Responsiveness: A Randomized Controlled Double-Blind Clinical Trial

The aims of this randomized controlled double-blind clinical trial were to assess the impact of vitamin D supplementation on calcium metabolism and non-calcemic broad gene expression by relating them to the individual’s responsiveness to varying doses of vitamin D₃. Thirty healthy adults were randomized to receive 600, 4,000 or 10,000 IU/d of vitamin D₃ for 6 months. Circulating parathyroid hormone (PTH), 25(OH)D, calcium and peripheral white blood cells broad gene expression were evaluated. We observed a dose-dependent increase in 25(OH)D concentrations, decreased PTH and no change in serum calcium. A plateau in PTH levels was achieved at 16 weeks in the 4000 and 10,000 IU/d groups. There was a dose-dependent 25(OH)D alteration in broad gene expression with 162, 320 and 1289 genes up- or down-regulated in their white blood cells, respectively. Our results clearly indicated that there is an individual’s responsiveness on broad gene expression to varying doses of vitamin D₃. Vitamin D₃ supplementation at 10,000 IU/d produced genomic alterations several fold higher than 4,000 IU/d even without further changes in PTH levels. Our findings may help explain why there are some inconsistency in the results of different vitamin D’s clinical trials.

Intake and contribution of food groups to vitamin D intake in a representative sample of adult Greek population

OBJECTIVES

Globally, vitamin D intake from food and supplements is low, consistent with the high prevalence of low serum 25-hydroxyvitamin D concentration. The aims of this study were to assess vitamin D intake and major relevant food contributors among Greek adults and to propose subsequent policies for intervention.

METHODS

Vitamin D from diet and supplements was estimated in adults (≥19 y of age) from two 24-h recalls using the Automated Multiple-Pass Method (vitamin D from food intake) and a drug and supplement questionnaire (vitamin D supplements). Over- and underreporters were identified using the Goldberg cutoff. The final analysis included 2218 individuals. The National Research Council method was used to account for within- and between-person variation. Vitamin D food intake adequacy was estimated based on the estimated average requirement (EAR) of 10 mcg/d, set by the Institute of Medicine. Major foods contributing to intake were identified and the effect on meeting EAR, of a potential food fortification example was examined.

RESULTS

Median vitamin D intake from food ranged from 1.16 to 1.72 and 1.01 to 1.26mcg/d in different age groups in men and women, respectively. Major food sources of vitamin D were fish (46%), meat (15%), and cereals (12%); however, >90% of the population in all age groups failed to meet the EAR, even when supplemental use was accounted for (~5% of the population consumed supplements).

CONCLUSION

Overall vitamin D intake is below the average requirements. Public health policies to increase the consumption of foods high in vitamin D or food fortification may significantly reduce the percentage of individuals who do not meet the recommendations.

Daily oral dosing of vitamin D3 using 5000 TO 50,000 international units a day in long-term hospitalized patients: Insights from a seven year experience

Vitamin D3 is a secosteroid hormone produced in the skin in amounts estimated up to 25,000 international units (IUs) a day by the action of UVB radiation on 7-dehydrocholesterol. Vitamin D deficiency is common due to both lack of adequate sun exposure to the skin, and because vitamin D is present in very few food sources. Deficiency is strongly linked to increased risk for a multitude of diseases, several of which have historically been shown to improve dramatically with either adequate UVB exposure to the skin, or to oral or topical supplementation with vitamin D. These diseases include asthma, psoriasis, rheumatoid arthritis, rickets and tuberculosis. All patients in our hospital have been routinely screened on admission for vitamin D deficiency since July 2011, and offered supplementation to either correct or prevent deficiency. During this time, we have admitted over 4700 patients, the vast majority of whom agreed to supplementation with either 5000 or 10,000 IUs/day. Due to disease concerns, a few agreed to larger amounts, ranging from 20,000 to 50,000 IUs/day. There have been no cases of vitamin D3 induced hypercalcemia or any adverse events attributable to vitamin D3 supplementation in any patient. Three patients with psoriasis showed marked clinical improvement in their skin using 20,000 to 50,000 IUs/day. Analysis of 777 recently tested patients (new and long-term) not on D3 revealed 28.7% with 25-hydroxyvitaminD3 (25OHD3) blood levels < 20 ng/ml, 64.1% < 30 ng/ml, a mean 25OHD3 level of 27.1 ng/ml, with a range from 4.9 to 74.8 ng/ml. Analysis of 418 inpatients on D3 long enough to develop 25OHD3 blood levels > 74.4 ng/ml showed a mean 25OHD3 level of 118.9 ng/ml, with a range from 74.4 to 384.8 ng/ml. The average serum calcium level in these 2 groups was 9.5 (no D3) vs 9.6 (D3), with ranges of 8.4 to 10.7 (no D3) vs 8.6 to 10.7 mg/dl (D3), after excluding patients with other causes of hypercalcemia. The average intact parathyroid hormone levels were 24.2 pg/ml (D3) vs. 30.2 pg/ml (no D3). In summary, long-term supplementation with vitamin D3 in doses ranging from 5000 to 50,000 IUs/day appears to be safe.

Vitamin D Status and Mortality: A Systematic Review of Observational Studies

Epidemiological evidence suggests that vitamin D deficiency is associated with increased mortality, but it is unclear whether this is explained by reverse causation, and if there are specific causes of death for which vitamin D might be important. We conducted a systematic review of observational studies investigating associations between circulating 25-hydroxyvitamin D (25(OH)D) concentration and all-cause or cause-specific mortality in generally healthy populations. Relevant studies were identified using PubMed and EMBASE searches. After screening 722 unique records and removing those that were ineligible, 84 articles were included in this review. The vast majority of studies reported inverse associations between 25(OH)D concentration and all-cause mortality. This association appeared to be non-linear, with progressively lower mortality with increasing 25(OH)D up to a point, beyond which there was no further decrease. There is moderate evidence that vitamin D status is inversely associated with cancer mortality and death due to respiratory diseases, while for cardiovascular mortality, there is weak evidence of an association in observational studies, which is not supported by the data from intervention or Mendelian randomization studies. The relationship between vitamin D status and other causes of death remains uncertain due to limited data. Larger long-term studies are required to clarify these associations.

Vitamin D status and its management for achieving optimal health benefits in the elderly

INTRODUCTION

Vitamin D deficiency is common, world-wide, but vitamin D repletion throughout life, and into older age, has accepted health benefits for bone. Many mechanisms through which vitamin D also benefits soft tissues are understood, and clinical evidence of such benefits is now accumulating, especially following re-analyses of trial data, which are revealing previously missed health benefits with correction of deficiency.

AREAS COVERED

The sources of vitamin D, its activation, mechanistic effects; problems of trials of supplementation for reducing health risks, the benefits shown for mortality, cardiovascular disease, infection and cancer; the global problem of vitamin D deficiency; age-related reductions in vitamin D efficacy, and currently recommended intakes.

EXPERT COMMENTARY

High prevalence of vitamin D deficiency and insufficiency worldwide have proven ill-effects on health. Governmental efforts to improve population repletion by recommending minimal daily intakes does benefit some but is not effective at the population-level. However, food fortification with vitamin D3, already implemented in some countries, can solve this highly avoidable problem cost-effectively and is probably the best way to abolish vitamin D inadequacy, allowing public health benefits to emerge over time, thereby allowing future research on vitamin D to be directed at emerging issues on vitamin D.