Comparative 25-OH-vitamin D level in institutionalized women older than 65 years from two cities in Spain and Argentina having a similar solar radiation index

Prevalence of vitamin D deficiency in South America: a systematic review and meta-analysis

CONTEXT

Vitamin D deficiency is considered a global public health issue, even in low-latitude countries where there is abundant sunlight radiation. Nevertheless, the prevalence of vitamin D insufficiency and deficiency in the South American continent has not been well characterized.

OBJECTIVE

The aim of this review was to estimate the prevalence of vitamin D deficiency (25-hydroxy-calciferol < 20 ng/mL) in South American populations.

DATA SOURCES

Seven electronic databases (MEDLINE, Web of Science, Embase, Biblioteca Virtual de Saúde, SciELO, Scopus, and Google Scholar) were searched systematically for observational studies published before July 1, 2021, and reporting vitamin D status of healthy adults in South America.

DATA EXTRACTION

Data were extracted using a standardized form. Risk of bias was assessed by the Joanna Briggs Institute Critical Appraisal Instrument for Studies Reporting Prevalence. All steps were conducted independently by two authors. Data were pooled using a random-effects model. Stratified meta-analysis and meta-regression were conducted (R software).

DATA ANALYSIS

Of 9460 articles identified, 96 studies with a total of 227 758 participants were included. The overall prevalence of vitamin D deficiency was 34.76% (79 studies; 95%CI, 29.68-40.21; I2 = 99%). There were significant differences in prevalence rates related to age, sex, country, latitude, season, and year of publication.

CONCLUSION

The prevalence of vitamin D deficiency is unexpectedly elevated in South American populations. Public health strategies should include efforts to prevent, detect, and treat vitamin D deficiency.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42020169439.

Vitamin D deficiency in nursing home residents: a systematic review

CONTEXT

Vitamin D deficiency is a global public health issue, particularly in nursing home residents.

OBJECTIVE

This review critically summarizes the prevalence of vitamin D deficiency in nursing home residents worldwide. In addition, it outlines the effect of vitamin D intervention, alone or in combination with other nutrients or therapies, on improving vitamin D status and associated health outcomes in nursing home residents.

DATA SOURCES, EXTRACTION, AND ANALYSIS

Searches were conducted of electronic databases for articles published from 2010 to May 2021. After screening of the 366 papers initially identified, 58 articles were included.

CONCLUSIONS

A paucity of observational studies in nursing homes suggests a high prevalence of vitamin D deficiency ranging from 8% [25(OH)D <25 nmol/L], up to 94% [25(OH)D <50 nmol/L] in some cohorts where supplement use was low. Reported factors associated with deficiency and suboptimal vitamin D status include lack of sunlight exposure, poor dietary intake of vitamin D, limited vitamin D food fortification, frailty, poor renal function, and low use of vitamin D supplements. Residents who are severely deficient, deficient, or insufficient in vitamin D require remedial vitamin D supplementation prior to maintenance supplementation at doses >800 IU/day. High-dose vitamin D supplementation may reduce respiratory illness; however, supportive data are limited. Oral nutritional supplements, in combination with exercise, may benefit physical function and performance, whereas supplementation with vitamin D- and calcium-fortified foods has been associated with improved quality of life and reduced bone resorption. Globally, vitamin D deficiency is highly prevalent in nursing home residents. There is an urgent need for standardized dietary and supplementation guidelines to prevent deficiency in this vulnerable group.

Vitamin D as a Shield against Aging

Aging can be seen as a physiological progression of biomolecular damage and the accumulation of defective cellular components, which trigger and amplify the process, toward whole-body function weakening. Senescence initiates at the cellular level and consists in an inability to maintain homeostasis, characterized by the overexpression/aberrant expression of inflammatory/immune/stress responses. Aging is associated with significant modifications in immune system cells, toward a decline in immunosurveillance, which, in turn, leads to chronic elevation of inflammation/oxidative stress, increasing the risk of (co)morbidities. Albeit aging is a natural and unavoidable process, it can be regulated by some factors, like lifestyle and diet. Nutrition, indeed, tackles the mechanisms underlying molecular/cellular aging. Many micronutrients, i.e., vitamins and elements, can impact cell function. This review focuses on the role exerted by vitamin D in geroprotection, based on its ability to shape cellular/intracellular processes and drive the immune response toward immune protection against infections and age-related diseases. To this aim, the main biomolecular paths underlying immunosenescence and inflammaging are identified as biotargets of vitamin D. Topics such as heart and skeletal muscle cell function/dysfunction, depending on vitamin D status, are addressed, with comments on hypovitaminosis D correction by food and supplementation. Albeit research has progressed, still limitations exist in translating knowledge into clinical practice, making it necessary to focus attention on the role of vitamin D in aging, especially considering the growing number of older individuals.

Vitamin D and Bone Health of Older Adults within Care Homes: An Observational Study

Limited studies have reported vitamin D status and health outcomes in care home residents, a group at risk of vitamin D deficiency. This study investigated serum 25-hydroxyvitamin D (25-OHD) concentrations in older adults within care homes in Northern Ireland (NI) and its association with musculoskeletal health (ultrasound T-score, muscle strength, Timed Up & Go test (TUG)), bone turnover markers (BTMs), and immune function markers. A total of 87 participants were recruited with mean ± SD age 83.2 ± 7.9 years. Mean ± SD serum 25-OHD concentration (n 69) was 49.52 ± 35.58 nmol/L. Vitamin D deficiency (25-OHD <25 nmol/L) was observed in 34.8% (n 24) of participants with 17.4% (n 12) classified as insufficient (25-OHD 25−50 nmol/L) and 47.8% (n 33) as sufficient (25-OHD >50 nmol/L). 25-OHD concentration was not an independent predictor of T-score, muscle strength, TUG, or inflammatory cytokines. After adjusting for covariates, a significant negative association was observed between 25-OHD concentration and the BTMs; osteocalcin (β = −0.395; p = 0.001), procollagen type 1 N propeptide (P1NP) (β = −0.320; p = 0.012), and C-terminal telopeptide of type 1 collagen (CTX) (β = −0.377; p = 0.003). Higher 25-OHD concentration was positively associated with use of vitamin D ± calcium supplementation (β = 0.610; p < 0.001). Vitamin D deficiency and insufficiency were highly prevalent in this sample of care home residents in NI. Higher 25-OHD concentration was associated with greater supplement use and with reduced bone turnover, which in this population is linked with reduced bone loss. These findings emphasize the need for a mandatory vitamin D ± calcium supplementation policy specific for care home residents.

Prevalence of Vitamin D Deficiency and Insufficiency in Kosovo Population

BACKGROUND: Vitamin D deficiency is a global health problem, but it is not known about its status in the Kosovo population. AIM: The purpose of this study is to determine the status of Vitamin D deficiency and insufficiency in our population. MATERIALS AND METHODS: Data collection was done from January 2020 to July 2021, during which period blood samples were collected. The sampling was done for 769 selected subjects and statistical data (frequency, mean values, and standard deviation) have been analyzed for 25-hydroxyvitamin D [25(OH)D] concentration. They were categorized by age group, gender, and level of 25(OH)D. The prevalence and percentage of Vitamin D deficiency and insufficiency in the study population were evaluated. RESULTS: The mean concentration of 25(OH)D in the serum of the study group was 18.3 ng/ml. The mean value was significantly lower for females when compared for that of males (17.89 and 19.58 ng/ml, respectively), with p < 0.0035, but there was no significant difference between age groups. The level of 25(OH)D less than 20 ng/ml was observed in 62% of the cases in our study population with a slight difference between female (63.6%) and male (57.2%) group. The age group of >60 had 25(OH)D deficiency in 62.3% of cases when compared to other age group categories. Vitamin D deficiency was present in 20.2% of cases; meanwhile, its insufficiency was present in 41.9% of cases. Vitamin D deficiency was observed in 21.1% of females and 17.1% of males, while 42.4% of females, respectively, and 40.1% of males had Vitamin D insufficiency. CONCLUSION: The mean values of 25(OH)D in the study population are relatively low, which corresponds to significant Vitamin D deficiency and insufficiency in all age groups, and which may also have serious implications for their overall health.

Vitamin Substitution Beyond Childhood—Requirements and Risks

BACKGROUND

Vitamins are vitally important, but they are not always adequately supplied with the diet. In this review, we present the advantages and disadvantages of vitamin supplementation and the indications for it in various life situations.

METHODS

This review is based on pertinent publications retrieved by a selective search of the literature.

RESULTS

The German National Nutrition Survey II (Nationale Verzehrsstudie II) showed that most people in Germany consume adequate amounts of vitamins in their diet, with the exception of vitamin D and folate. Supplements are often taken by adults who already consume a balanced diet. Depending on the vitamin, 3-13% of survey respondents took vitamin supplements; the ones most often taken were vitamins C and E. No convincing evidence has yet demonstrated a health benefit from vitamin supplementation in addition to a balanced diet for the primary prevention of nutrition-associated diseases. Vitamin supplementation is indicated in certain specific life situations, e.g., pregnancy, but otherwise unnecessary, unless a deficiency has been diagnosed or the individual is at elevated risk.

CONCLUSION

Vitamin supplementation is recommended for certain population groups: folic acid for pregnant women, vitamin B12 for vegans and persons with resorption disorders, vitamin D for persons with insufficient endogenous synthesis. In all other cases, it should first be tested whether the individual might be substantially helped by dietary changes alone. In general, the potential adverse effects of vitamin supplementation need to be considered, and its benefits weighed against its risks.

Are Shiftwork and Indoor Work Related to D3 Vitamin Deficiency? A Systematic Review of Current Evidences

Background

Reported cases of vitamin D3 deficiency have been increasing in incidence worldwide. Although there is a lack of consensus relating to optimal levels of vitamin D, generally serum 25-(OH)D concentrations lower than 50 nmol/L (20 ng/mL) are at least considered to be detrimental to bone health.

Aim

Aim of this systematic review is to investigate if occupations, and specifically shiftworking and indoor working, may be considered as possible contributors to the increased incidence of vitamin D3 deficiency in industrialized nations.

Materials and Methods

Systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement using PubMed, Scopus, and ISI Web of Knowledge databases.

Results

Overall 90 papers were found, 23 articles through PubMed, 30 through Scopus, and 37 through ISI Web of Knowledge. Successively, 46 duplicates and 34 articles that did not respect the inclusion criteria were excluded. Finally 10 articles were selected: 9 cross-sectional studies and 1 systematic review. Results of the studies included revealed that certain occupations are either suffering from, or have a predilection to suffer from, a deficiency of this vitamin. Shiftworkers and indoor workers are consistently reported as being the occupational group most likely to suffer from a deficiency of vitamin D3. It would appear prudent to investigate the potential of providing nutritional education to workers in addition to including preventative measures in the workplace.

Vitamin D deficiency in older adults and its associated factors: a cross-sectional analysis of the Mexican Health and Aging Study

Vitamin D deficiency was common in older adults from a country with adequate sun exposure. The variables associated with this deficiency provide insight into the next steps needed to characterize older adults with this deficiency and to treat it accordingly.

PURPOSE

The aim of this study was to describe the prevalence of and factors associated with vitamin D deficiency among Mexican older adults.

METHODS

This was a secondary analysis of the last wave of the Mexican Health and Aging Study. Vitamin D levels along with other biomarkers were obtained from a sub-sample of Mexican adults older than 60 years. Prevalence was described by sex and age group, and a multivariate analysis was performed to test the factors associated with this condition.

RESULTS

Data from 1088 adults over the age of 60 years were analyzed. The mean serum vitamin D level was 23.1 ± 8.1 ng/mL and was significantly higher among men than women (25.6 ± 0.6 and 22.8 ± 0.5 ng/mL, respectively; p < 0.001). In total, 37.3% (n = 406) presented with vitamin D deficiency, 65% of whom were women. Low 25-(OH)-vitamin D levels were associated with female sex (OR 1.74, 95% CI 1.59-2.42), current smoking (OR 2.21, 95% CI 1.47-3.39), education (OR 1.1, 95% CI 1.06-1.13), physical activity (OR 1.74, 95% CI 1.31-2.23), and high levels of glycated hemoglobin (OR 1.16, 95% CI 1.07-1.25).

CONCLUSIONS

Vitamin D deficiency was highly prevalent in Mexican older adults and was associated with a number of factors, indicating the multifactorial causality of this deficiency.

Global Overview of Vitamin D Status

Vitamin D deficiency occurs all over the world, mainly in the Middle East, China, Mongolia, and India. This article focuses on the vitamin D status in adults. Risk groups include older persons, pregnant women, and non-Western immigrants. Adequate vitamin D status, defined as serum 25-hydroxyvitamin D greater than 50 nmol/L, is present in less than 50% of the world population, at least in winter. Preventative strategies, such as increasing fish consumption, fortification of foods, use of vitamin D supplements, and advice for moderate sunlight exposure, are warranted.

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.

Nutritional modulation of age-related changes in the immune system and risk of infection

The immune system undergoes some adverse alterations during aging, many of which have been implicated in the increased morbidity and mortality associated with infection in the elderly. In addition to intrinsic changes to the immune system with aging, the elderly are more likely to have poor nutritional status, which further impacts the already impaired immune function. Although the elderly often have low zinc serum levels, several manifestations commonly observed during zinc deficiency are similar to the changes in immune function with aging. In the case of vitamin E, although its deficiency is rare, the intake above recommended levels is shown to enhance immune functions in the elderly and to reduce the risk of acquiring upper respiratory infections in nursing home residents. Vitamin D is a critical vitamin in bone metabolism, and its deficiency is far more common, which has been linked to increased risk of infection as demonstrated in a number of observational studies including those in the elderly. In this review, we focus on zinc, vitamin E, and vitamin D, the 3 nutrients which are relatively well documented for their roles in impacting immune function and infection in the elderly, to discuss the findings in this context reported in both the observational studies and interventional clinical trials. A perspective will be provided based on the analysis of information under review.

Vitamin D Intake and Serum 25-Hydroxyvitamin D Levels in Korean Adults: Analysis of the 2009 Korea National Health and Nutrition Examination Survey (KNHANES IV-3) Using a Newly Established Vitamin D Database

Vitamin D is important for maintaining bone health and may prevent various diseases (i.e., cardiovascular disease and cancer). The aim of this study was to estimate vitamin D intakes of Korean adults using the Korea National Health and Nutrition Examination Survey (KNHANES, 2009) data and a newly established vitamin D database. KNHANES (2009) participants (n = 4541; 2021 men; 2520 women) aged ≥20 years were included. Dietary vitamin D intake, serum 25-hydroxyvitamin D (25(OH)D), and the relationship between vitamin D intake and serum 25(OH)D were evaluated. In men and women, vitamin D intakes were 4.00 ± 0.17 µg/day and 2.6 ± 0.1 µg/day respectively, and serum 25(OH)D concentrations were 19.78 ± 0.33 ng/mL and 17.10 ± 0.26 ng/mL respectively. Serum 25(OH)D concentrations of men aged <50 years and women aged >20 years were under 20 ng/mL. After adjusting for confounding factors, the positive relationship between vitamin D intake and serum 25(OH)D was observed in total subjects (p < 0.05), excluding participants ≥50 years old. The main food sources for vitamin D among Korean adults were fish/shellfish (71.34%) and egg (14.89%). Korean adults should increase their serum 25(OH)D concentrations by increasing vitamin D intake.

Is reactivation of toxoplasmic retinochoroiditis associated to increased annual rainfall?

BACKGROUND

Reactivation of toxoplasmic retinochoroiditis is the most frequent form of uveitis in Misiones, Argentina. Fluctuations in the number of patients consulting with this type of uveitis were detected during the last decade. Since the province was consecutively exposed to rainy and dry periods over the last years, we decided to explore whether a relationship between reactivation of toxoplasmic retinochoroiditis and rain might be established according to the data registered during the 2004-2010 period.

RESULTS

The frequency of toxoplasmic reactivation episodes increases when precipitation increases (mostly in second and fourth trimesters of each year). Analysis of the independent variables demonstrates that precipitation is a significant predictor of the frequency of reactivation episodes. Although registered toxoplasmic reactivations were more frequent during the third trimester of the year, the association between the third trimester and the reactivation episodes did not reach statistical significance.

CONCLUSION

Prolonged and intense rainfall periods were significantly associated with the reactivation of toxoplasmic retinochoroiditis. Changes promoted by this climatic condition on both the parasite survival in the soil as well as a putative effect on the host immune response due to other comorbidities are discussed.

Effects of sunlight and diet on vitamin D status of pulmonary tuberculosis patients in Tbilisi, Georgia

OBJECTIVE

Vitamin D deficiency is common in tuberculosis (TB) and this may modulate immune responses. This study investigated vitamin D status in patients with TB and examined the sources of vitamin D in Tbilisi, Georgia.

METHODS

We measured plasma 25-hydroxyvitamin D (25[OH]D) and dietary vitamin D intake in patients with pulmonary TB (n = 85) in Tbilisi, Georgia. To determine the impact of season on vitamin D status, we tested the in vitro conversion of 7-dehydrocholesterol (7-DHC) to previtamin D(3) after sunlight exposure.

RESULTS

In subjects with TB, mean plasma 25(OH)D concentrations were 14.4 ± 7.0 ng/mL, and vitamin D insufficiency (25[OH]D <30 ng/mL) occurred in 97% of subjects. The dietary sources of vitamin D were mainly fish, eggs, and butter. The daily intake was well below recommended daily intakes in subjects with TB (172 ± 196 IU). The conversion of 7-DHC to previtamin D(3) was undetectable from October to March and highest in June and July from 11:00 to 14:00 h.

CONCLUSION

An insufficient vitamin D dietary intake and a limited production of vitamin D from sunlight for most of the year may explain the high prevalence of vitamin D insufficiency in patients with TB in Tbilisi.

Worldwide vitamin D status

The aim of the present study is to summarize existing literature on vitamin D levels in adults in different continents and different countries worldwide. The best determinant of vitamin D status is the serum concentration of 25-hydroxyvitamin D (25(OH)D). Most investigators agree that serum 25(OH)D should be higher than 50 nmol/l, but some recommend higher serum levels. Traditional risk groups for vitamin D deficiency include pregnant women, children, older persons, the institutionalized, and non-western immigrants. This chapter shows that serum 25(OH)D levels are not only suboptimal in specific risk groups, but also in adults in many countries. Especially, in the Middle-East and Asia, vitamin D deficiency in adults is highly prevalent.

Hypovitaminosis D in developing countries-prevalence, risk factors and outcomes

Hypovitaminosis D is a prevalent disorder in developing countries. Clinical manifestations of hypovitaminosis D include musculoskeletal disorders, such as nonspecific muscle pain, poor muscle strength and low BMD, as well as nonmusculoskeletal disorders, such as an increased risk of respiratory infections, diabetes mellitus and possibly cardiovascular diseases. In developing countries, the prevalence of hypovitaminosis D varies widely by and within regions; prevalence ranges between 30-90%, according to the cut-off value used within specific regions, and is independent of latitude. A high prevalence of the disorder exists in China and Mongolia, especially in children, of whom up to 50% are reported to have serum 25-hydroxyvitamin D levels <12.5 nmol/l. Despite ample sunshine throughout the year, one-third to one-half of individuals living in Sub-Saharan Africa and the Middle East have serum 25-hydroxyvitamin D levels <25 nmol/l, according to studies published in the past decade. Hypovitaminosis D is also prevalent in children and the elderly living in Latin America. Risk factors for hypovitaminosis D in developing countries are similar to those reported in Western countries and include extremes of age, female sex, winter season, dark skin pigmentation, malnutrition, lack of sun exposure, a covered clothing style and obesity. Clinical trials to assess the effect of vitamin D supplementation on classical and nonclassical clinical outcomes in developing countries are needed.