The risk of all-cause mortality is inversely related to serum 25(OH)D levels

Effect of sunlight on vitamin D and hemoglobin levels among the residents of Ningbo, China

Introduction

Objective: this study investigated the effect of sunlight on vitamin D and hemoglobin levels among the residents of Ningbo, China. The impact of gender, age, and season on vitamin D and hemoglobin levels was also explored. Methods: a total of 8,481 research subjects, including 5,146 men and 3,335 women, who were permanent residents of Ningbo and received health checkups at Ningbo Second Hospital, were included in the study. Ningbo City climate bulletin data from 2019 to 2022 was also included. Results: the study subjects received an average of 132.20 ± 40.05 h of sunlight exposure per month and had average vitamin D levels of 19.63 ± 6.61 ng/ml. Hemoglobin levels were adequate in 85.4 % of the participants and deficient in 14.6 %. Sunlight exposure correlated positively with vitamin D and negatively with hemoglobin levels. Regression analysis indicated that gender, age, and season affected vitamin D and hemoglobin levels to different degrees. Conclusion: in Ningbo, vitamin D deficiency was common in adults while hemoglobin levels were mostly normal. The amount of sunlight exposure had a significant effect on vitamin D and hemoglobin levels and this relationship was impacted by gender, age, and season.

Serum 25(OH)D Concentration, Vitamin D Supplementation, and Risk of Cardiovascular Disease and Mortality in Patients with Type 2 Diabetes or Prediabetes: a Systematic Review and Dose-Response Meta-Analysis

BACKGROUND

Evidence is uncertain about the association between serum 25-hydroxyvitamin D (25(OH)D) concentration and health outcomes in people with type 2 diabetes.

OBJECTIVES

We aimed to assess the association between vitamin D status and all-cause mortality and cardiovascular disease in people with type 2 diabetes.

METHODS

We did a systematic search in PubMed, Scopus, CENTRAL, and Web of Science until May 2022. We selected 1) cohort studies investigating the association between serum 25(OH)D concentration and mortality or cardiovascular disease in people with type 2 diabetes or prediabetes and 2) randomized trials of vitamin D supplementation in these patients. We used random-effects pairwise meta-analyses to calculate summary relative risks (RRs) and 95% confidence intervals (CI).

RESULTS

21 cohort studies and 6 randomized trials were included. Compared with sufficient vitamin D status (≥50 nmol/L), the RR of all-cause mortality was 1.36 (95% CI: 1.23, 1.49; n = 11 studies, GRADE = moderate) for vitamin D insufficiency (25 to <50 nmol/L), and 1.58 (1.33, 1.83; n = 16, GRADE = moderate) for deficiency (<25 nmol/L). Similar findings were observed for cardiovascular mortality and morbidity but not for cancer mortality. The certainty of evidence ranged from very low to moderate. Dose-response meta-analyses indicated nonlinear associations, with the lowest risk at 25(OH)D ∼60 nmol/L for all-cause and cardiovascular mortality. Supplementation with vitamin D did not reduce the risk of all-cause mortality (RR: 0.96, 95% CI: 0.79, 1.16; risk difference per 1000 patients: 3 fewer, 95% CI: 16 fewer, 12 more; n = 6 trials with 7316 participants; GRADE = low) or the risk of cardiovascular mortality and morbidity (very low- to low-certainty evidence).

CONCLUSIONS

Vitamin D deficiency and insufficiency are associated with a higher risk of all-cause and cardiovascular mortality in patients with type 2 diabetes or prediabetes. Vitamin D deficiency should be corrected in patients with type 2 diabetes to reach normal serum 25(OH)D concentrations, preferably 60 nmol/L.

SYSTEMATIC REVIEW REGISTRATION

This systemic review was registered at PROSPERO as CRD42022326429 (=https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=326429).

Hypovitaminosis D and Metabolic Syndrome in Postmenopausal Women

Metabolic syndrome (MetSyn) is a precursor for several cardiometabolic diseases. The prevalence of MetSyn is higher in postmenopausal women compared to premenopausal women. The role of vitamin D in postmenopausal women is not clearly understood. Hypovitaminosis D is more prevalent in postmenopausal women compared to premenopausal women. For this review, Pubmed, Cochrane, SCOPUS, Embase, and Google Scholar databases were searched up to August 2022. Findings from one randomized controlled trial (RCT) and ten cross-sectional studies were included in this review. Several cross-sectional studies (8 out of 10 reviewed) unequivocally demonstrated an inverse association between serum 25-hydroxyvitamin D concentrations and MetSyn. However, RCTs are severely lacking in the effect of vitamin D intake on the biomarkers of MetSyn and the prevalence of MetSyn. Therefore, caution should be used in recommending mega doses of vitamin D supplements for postmenopausal women because of the potential adverse effects associated with this vitamer.

Serum 25-hydroxyvitamin D, frailty, and mortality among the Chinese oldest old: Results from the CLHLS study

BACKGROUND AND AIMS

In this study, the aim is to explore whether frailty status modified the associations of serum 25(OH)D levels with all-cause and cause-specific mortality in the oldest old Chinese population.

METHODS AND RESULTS

A total of 1411 participants aged at least 80 years were enrolled in the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Information on serum 25(OH)D level, frailty status, and covariates were examined at baseline. All-cause and cause-specific mortality status were ascertained during the follow-up survey conducted in 2017-2018 by using the ICD-10 codes. Cox proportional hazard models with stratified analyses were performed to evaluate potential associations. Over a median follow-up of 3.2 years, 722 (51.2%) participants were deceased, including 202 deaths due to circulatory diseases, and 520 deaths due to noncirculatory causes. After multivariable adjustment, the lowest quartile of serum 25(OH)D levels (Hazard Ratios (95% Confidence Intervals), 1.85 (1.45-2.36), 1.85 (1.45-2.36), 1.73 (1.31-2.29), respectively) and frailty (Odd Ratios (95% Confidence Intervals), 1.91 (1.60-2.29), 2.67 (1.90-3.74), 1.64 (1.31-2.05)) were associated with significantly higher risk of all-cause mortality, circulatory mortality, and noncirculatory mortality, respectively. In addition, we observed significant interactions among 25(OH)D and frailty on the risk of all-cause and cause-specific mortality (all P-interaction < 0.001). Similar results were found in sensitivity analyses by excluding participants who died in the first year of follow-up and using clinical cutoffs of serum 25(OH)D levels.

CONCLUSION

Low serum 25(OH)D levels were associated with higher risk of all-cause and cause-specific mortality among the oldest old of the Chinese population, and the associations were significantly stronger in individuals with frailty.

Vitamin D supplementation: upper limit for safety revisited?

Vitamin D overdosing includes hypercalcemia, hypercalciuria, and mineral deposits in soft tissues. A safety upper limit of 4000 IU/day, which is consistently accepted, has been challenged, since the risk of adverse events in other systems than calcium-phosphate homeostasis may depend not only on the dose, but on the outcome, the treatment regimen, and possibly the age, sex and vitamin D status. The therapeutic window of vitamin D supplementation may be narrower than hitherto recognized. The prevention and/or correction of vitamin D deficiency/insufficiency with 800–1000 IU/daily of vitamin D or 10 µg/day of calcifediol are safe. Because of their potential harm, larger doses given on the long term or in intermittent regimens should not be selected.

Sub-optimal serum 25-hydroxyvitamin D level affects 2-year survival after hip fracture surgery

INTRODUCTION

Hypovitaminosis D is a common condition seen in patients with acute hip fracture. We hypothesize that in addition to the other prognosticating factors, hypovitaminosis D may affect survival in patients treated for hip fractures. The objective of this study is to evaluate the impact of serum level of 25-hydroxyvitamin D (25(OH)D) on the survivability after surgical fixation of hip fractures.

MATERIALS AND METHODS

We retrospectively studied data collected from January 2013 through December 2015 at a large tertiary hospital in Singapore. Patient's age, gender, Charlson Comorbidity Index (CCI), delay of surgery, fracture patterns, ASA score, as well as their pre-operative serum levels of 25(OH)D, albumin and calcium were examined. Univariate and multivariate logistic regression were used to analyse post-operative outcomes including short (inpatient, 30 and 90 days) and long-term mortality (2 years).

RESULTS

Data from 1004 patients were used. Information on the serum level of 25(OH)D was available in 80% of them (n = 801) and more than 90% (n = 735) of the patients had a baseline serum level of less than 30 ng/ml. Mortality rate within this group were 1.1% (n = 9) at 30 days, 1.9% (n = 15) at 90 days and 11.0% (n = 88) at 2 years follow up. Hypovitaminosis D was not a significant risk predictor for short-term mortality, but found to be a significant predictor at 2 years.

CONCLUSIONS

In this study, we showed a high prevalence of hypovitaminosis D among the osteoporotic hip fracture population and its impact on 2-year survivorship after hip fracture surgery.

Plasma 25-Hydroxyvitamin D Concentrations Are Inversely Associated with All-Cause Mortality among a Prospective Cohort of Chinese Adults Aged ≥80 Years

BACKGROUND

High concentrations of plasma 25-hydroxyvitamin D [25(OH)D], a marker of circulating vitamin D, have been associated with a lower risk of mortality in epidemiologic studies of multiple populations, but the association for Chinese adults aged ≥80 y (oldest old) remains unclear.

OBJECTIVE

We investigated the association between plasma [25(OH)D] concentration and all-cause mortality among Chinese adults aged ≥80 y.

DESIGN

The present study is a prospective cohort study of 2185 Chinese older adults (median age: 93 y). Prospective all-cause mortality data were analyzed for survival in relation to plasma 25(OH)D using Cox proportional hazards regression models, with adjustments for potential sociodemographic and lifestyle confounders and biomarkers. The associations were measured with HR and 95% CIs.

RESULTS

The median plasma 25(OH)D concentration was 34.4 nmol/L at baseline. Over the 5466 person-year follow-up period, 1100 deaths were identified. Men and women were analyzed together as no effect modification by sex was found. After adjusting for multiple potential confounders, the risk of all-cause mortality decreased as the plasma 25(OH)D concentration increased (P-trend <0.01). Compared with the lowest age-specific quartile of plasma 25(OH)D, the adjusted HRs for mortality for the second, third, and fourth age-specific quartiles were 0.72 (95% CI: 0.57, 0.90), 0.73 (95% CI: 0.58, 0.93), and 0.61 (95% CI: 0.47, 0.81), respectively. The observed associations were broadly consistent across age and other subgroups. Sensitivity analyses generated similar results after excluding participants who died within 2 y of follow-up or after further adjustment for ethnicity and chronic diseases.

CONCLUSIONS

A higher plasma 25-hydroxyvitamin D concentration was associated with a reduced risk of all-cause mortality among Chinese adults aged ≥80 y. This observed inverse association warrants further investigation in randomized controlled trials testing vitamin D supplementation in this age group.

Current vitamin D status in European and Middle East countries and strategies to prevent vitamin D deficiency: a position statement of the European Calcified Tissue Society

Vitamin D deficiency (serum 25-hydroxyvitamin D (25(OH)D) <50 nmol/L or 20 ng/mL) is common in Europe and the Middle East. It occurs in <20% of the population in Northern Europe, in 30-60% in Western, Southern and Eastern Europe and up to 80% in Middle East countries. Severe deficiency (serum 25(OH)D <30 nmol/L or 12 ng/mL) is found in >10% of Europeans. The European Calcified Tissue Society (ECTS) advises that the measurement of serum 25(OH)D be standardized, for example, by the Vitamin D Standardization Program. Risk groups include young children, adolescents, pregnant women, older people (especially the institutionalized) and non-Western immigrants. Consequences of vitamin D deficiency include mineralization defects and lower bone mineral density causing fractures. Extra-skeletal consequences may be muscle weakness, falls and acute respiratory infection, and are the subject of large ongoing clinical trials. The ECTS advises to improve vitamin D status by food fortification and the use of vitamin D supplements in risk groups. Fortification of foods by adding vitamin D to dairy products, bread and cereals can improve the vitamin D status of the whole population, but quality assurance monitoring is needed to prevent intoxication. Specific risk groups such as infants and children up to 3 years, pregnant women, older persons and non-Western immigrants should routinely receive vitamin D supplements. Future research should include genetic studies to better define individual vulnerability for vitamin D deficiency, and Mendelian randomization studies to address the effect of vitamin D deficiency on long-term non-skeletal outcomes such as cancer.

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.

Open-label study of treatment with alendronate sodium plus vitamin D in men and women with osteoporosis in Thailand

Background

It is generally believed that Thai people do not suffer from hypovitaminosis D because there is abundant sunlight throughout the year, and that taking vitamin D supplements could result in abnormally high levels of vitamin D. This is a Thai FDA-driven study to investigate this risk over a period of 26 weeks of taking alendronate sodium/vitamin D3 combination tablets.

Methods

Osteoporosis patients in Thailand were recruited to a multicenter, open-label, 6-month trial of oral alendronate sodium 70 mg/vitamin D3 5600 IU. Patients received study medication once a week for 26 weeks. Serum 25-hydroxyvitamin D (25(OH)D) and Beta-CrossLaps (β-CTx) levels were measured at baseline and 26 weeks. The primary endpoint was the proportion of patients with 25(OH)D ≥ 50 ng/mL at week 26; it was hypothesized that 26 weeks’ treatment would not result in 25(OH)D serum levels ≥ 50 ng/mL in > 7% of osteoporosis patients.

Results

One hundred ninety-eight patients were recruited. At baseline, 67.2% of the patients had 25(OH)D < 30 ng/mL; this declined to 34.4% by week 26. The mean 25(OH)D level improved from 27.8 ng/mL at baseline to 33.6 ng/mL at week 26. Five patients (2.69% of the full analysis set) had 25(OH)D levels ≥ 50 ng/mL at 26 weeks. The highest 25(OH)D level, 64.3 ng/mL, was observed in a patient whose baseline level was 102.2 ng/mL. The majority (62.9%) of the patients had optimal 25(OH)D levels (30–50 ng/mL). β-CTx levels were reduced by 57.7% after 26 weeks’ treatment. No clinically significant cases of hypercalcemia which could be associated with hypervitaminosis D were identified during physical examination, in vital signs, or in laboratory results. Overall, 73 patients (36.9%) reported at least one adverse event (AE), with 13 (6.6%) reporting drug-related AEs. Four patients discontinued due to AEs, two of which were drug-related. Serious AEs were reported for four patients, of which one was considered drug-related.

Conclusions

Oral alendronate sodium 70 mg plus vitamin D3 5600 IU once weekly had an acceptable safety profile in this study, and increased serum 25(OH)D and reduced β-CTx levels in osteoporosis patients. This treatment improved 25(OH)D levels, without causing abnormally high levels, after 26 weeks’ treatment.

Trial registration

Clinical Trials.gov NCT01437111, Registered September 19, 2011.

Vitamin D deficiency and infection risk in kidney transplant recipients: A single-center cohort study

BACKGROUND

Recent studies have reported an increased susceptibility to infection among vitamin D-deficient kidney transplant (KT) recipients, although methodological concerns remain.

METHODS

Serum 25-hydroxyvitamin D (25(OH)D) levels were measured in 246 KT recipients at post-transplant months 1, 3, 6 and 12. Vitamin D status was analysed in terms of deficiency (Endocrine Society [<20 ng/mL] and Institute of Medicine [IoM, <12 ng/mL] criteria) and as a continuous variable. Cox models for overall, bacterial and opportunistic infection were adjusted for nutritional status and immunosuppression-related covariates.

RESULTS

Median serum 25(OH)D increased from month 1 (10.5 ng/mL) to month 6 (16.3 ng/mL; P-value = 0.001). Prevalence of vitamin D deficiency at month 1 ranged from 87.0% to 61.0% (depending on the diagnostic criteria) and significantly decreased over the next months. After adjustment for age and nutritional status, vitamin D deficiency (serum 25(OH)D < 12 ng/mL) at month 1 was an independent risk factor for overall (hazard ratio [HR]: 1.70; 95% confidence interval [CI]: 1.08-2.69; P-value = 0.023) and opportunistic infection (HR: 4.05; 95% CI: 1.57-10.46; P-value = 0.004), but not for bacterial infection. A protective effect for overall (adjusted HR: 0.76; 95% CI: 0.63-0.93; P-value = 0.007) and opportunistic infection (adjusted HR: 0.62; 95% CI: 0.45-0.86; P-value = 0.004) was observed when 25(OH)D levels were analyzed per one-quartile increases.

CONCLUSIONS

Vitamin D status influences the risk of infection among KT recipients, with the association being particularly evident for opportunistic events and mainly restricted to the early post-transplant period.

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

OBJECTIVE

To determine the relationship between 25-hydroxyvitamin D (25[OH]D) values and all-cause and cause-specific mortality.

PATIENTS AND METHODS

We identified all serum 25(OH)D measurements in adults residing in Olmsted County, Minnesota, between January 1, 2005, and December 31, 2011, through the Rochester Epidemiology Project. All-cause mortality was the primary outcome. Patients were followed up until their last clinical visit as an Olmsted County resident, December 31, 2014, or death. Multivariate analyses were adjusted for age, sex, race/ethnicity, month of measurement, and Charlson comorbidity index score.

RESULTS

A total of 11,022 individuals had a 25(OH)D measurement between January 1, 2005, and December 31, 2011, with a mean ± SD value of 30.0±12.9 ng/mL. Mean age was 54.3±17.2 years, and most were female (77.1%) and white (87.6%). There were 723 deaths after a median follow-up of 4.8 years (interquartile range, 3.4-6.2 years). Unadjusted all-cause mortality hazard ratios (HRs) and 95% CIs for 25(OH)D values of less than 12, 12 to 19, and more than 50 ng/mL were 2.6 (95% CI, 2.0-3.2), 1.3 (95% CI, 1.0-1.6), and 1.0 (95% CI, 0.72-1.5), respectively, compared with the reference value of 20 to 50 ng/mL. In a multivariate model, the interaction between the effect of 25(OH)D and race/ethnicity on mortality was significant (P<.001). In white patients, adjusted HRs for 25(OH)D values of less than 12, 12 to 19, 20 to 50, and greater than 50 ng/mL were 2.5 (95% CI, 2.2-2.9), 1.4 (95% CI, 1.2-1.6), 1.0 (referent), and 1.0 (95% CI, 0.81-1.3), respectively. In patients of other race/ethnicity, adjusted HRs were 1.9 (95% CI, 1.5-2.3), 1.7 (95% CI, 1.1-2.6), 1.5 (95% CI, 1.0-2.0), and 2.1 (95% CI, 0.77-5.5).

CONCLUSION

White patients with 25(OH)D values of less than 20 ng/mL had greater all-cause mortality than those with values of 20 to 50 ng/mL, and white patients had greater mortality associated with low 25(OH)D values than patients of other race/ethnicity. Values of 25(OH)D greater than 50 ng/mL were not associated with all-cause mortality.

No Evidence for Lower Levels of Serum Vitamin D in the Presence of Hepatic Steatosis. A Study on the Portuguese General Population

Introduction and aims: Nonalcoholic fatty liver disease (NAFLD) has become highly prevalent, paralleling the pandemic of obesity and diabetes, and represents an important burden. Nutrition knowledge is fundamental, in prevention, evolution and treatment of NAFLD. Association of low serum levels of vitamin D (VD) with several diseases, including NAFLD, has been emphasized in the last decade. We evaluated how serum levels of VD correlate with the presence of hepatic steatosis, and VD intake, in a random sample of the Portuguese adult population. Methods: Participants underwent a dietary intake inquiry, using a semi-quantitative food frequency questionnaire representative of the usual intake over the previous year. Anthropometric measures, blood tests and ultrasound were done. Hepatic steatosis was quantified according to Hamaguchi's ultrasonographic score (steatosis defined by a score ≥ 2). Results: We recruited 789 adult individuals, 416 males (52.7%), mean age of 49.9 ± 17.0 years (18-79). Prevalence of hepatic steatosis was 35.5%, and after exclusion of excessive alcohol consumption, 28.0%. Mean VD serum levels were 26.0 ± 9.8 ng/ml and 68.4% participants had serum VD levels below 30 ng/ml. Mean serum levels of VD were not significantly different between participants with steatosis vs. no steatosis: 25.2±8.7 vs. 26.4±10.3 ng/ml, respectively (p=0.071). There was no correlation between VD serum levels and VD intake, measured by the FFQ, r=0.075 (p= 0.383). Conclusions: In spite of a high prevalence rate, there was no evidence that decreased VD serum levels were associated with hepatic steatosis. No significant correlation was found between VD dietary ingestion and VD serum levels.

Factor XI deficiency is associated with lower risk for cardiovascular and venous thromboembolism events

Factor XI deficiency is associated with reduced risk of cardiovascular events. Factor XI deficiency is associated with reduced risk of VTE.

Changes in circulating vitamin D levels with loss of adipose tissue

PURPOSE OF REVIEW

Low vitamin D levels have been extensively reported in obesity. Thus, the pandemic of obesity has been paralleled by a high prevalence of low vitamin D status. Given the well documented associations linking poor vitamin D status to adverse health outcomes (diabetes, cardiovascular disease, cancers, all-cause mortality), a proper understanding of the mechanisms linking excess adiposity to low vitamin D status is key to identify and implement effective interventions to replenish vitamin D levels in obese individuals. In this review, we will discuss recent literature investigating the effects of adipose tissue volume loss through energy restriction and/or physical activity on circulating 25-hydroxyvitamin D [25(OH)D] levels.

RECENT FINDINGS

Improvements of circulating 25(OH)D levels with adiposity loss through lifestyle interventions without supplementation is being reported by a growing number of studies, including recent randomized controlled trials.

SUMMARY

Low 25(OH)D is one of the metabolic disturbances associated with excess adiposity, particularly visceral adiposity. Recommendations for the treatment of obesity-related vitamin D deficiency should emphasize the role of visceral adiposity loss through healthy lifestyle habits, in conjunction with weight-adjusted vitamin D supplementation, not only to replenish 25(OH)D levels but also to address other visceral adiposity-related disturbances, such as insulin resistance, inflammation, hypertension, and dyslipidemia.

Red cell distribution width and all-cause mortality in patients with atrial fibrillation: A cohort study

Background

Increased red cell distribution width (RDW), a measure of red cell size variability, has been associated with increased mortality in multiple cardiovascular diseases. However, whether RDW is associated with increased mortality in patients with atrial fibrillation remains unknown.

Methods

Using the computerized database of the largest health maintenance organization in Israel, we identified a cohort of adults with atrial fibrillation diagnosed before January 1, 2012. Cardiovascular risk factors and comorbidities were ascertained using an electronic medical record–based algorithm. Mortality was established using the National Death Index through December 31, 2013.

Results

Of 69,412 patients, 12,104 (17.4%) participants died during follow-up. The crude, two-year cumulative all-cause mortality rate increased across RDW quartiles; 9.8%, 13.6%, 18.8%, and 28.5%, respectively. After adjustment for age, sex, anemia, cardiovascular risk factors, comorbidities, and medication use, compared to the lowest RDW quartile, the hazard ratio (HR) for mortality was 1.20 (95% CI, 1.13–1.27) in the second quartile, 1.44 (1.36–1.53) in the third quartile, and 1.90 (1.79–2.00) in the highest RDW quartile. The results were similar after further adjustment for smoking, socioeconomic status, renal function, low and high density lipoprotein cholesterol levels, with HR=1.82 (1.71–1.93) in the highest RDW quartile compared to the lowest quartile. Changes in RDW over time were strongly associated with mortality; increased RDW was associated with higher risk of mortality and decline in RDW was associated with decreased mortality.

Conclusions

RDW and changes in RDW are independently associated with the risk of all-cause mortality in patients with atrial fibrillation.

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We studied the association of RDW with mortality in patients with atrial fibrillation.

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RDW predicts mortality in patients with atrial fibrillation, regardless of anemia status.

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Changes in RDW are associated with mortality in patients with atrial fibrillation.

Neutrophil to lymphocyte ratio and risk of a first episode of stroke in patients with atrial fibrillation: a cohort study

BACKGROUND

The neutrophil to lymphocyte ratio (NLR) is associated with increased risk of cardiovascular morbidity and mortality. We aimed to assess the association between NLR and first episode of stroke in patients with atrial fibrillation.

METHODS

Using the computerized database of the largest HMO in Israel, we identified a cohort of adults, aged 20 years or older, with atrial fibrillation diagnosed before 1 January 2012. Eligible subjects had no prior stroke or TIA, were not on anticoagulants at baseline, and had at least one blood cell count performed in 2011. The cohort (32,912 subjects) was followed for the first event of stroke or TIA until 31 December 2012.

RESULTS

Overall 981 subjects developed stroke during a follow-up of 30,961 person-years (stroke rate, 3.17 per 100 person-years). The incidence rate of stroke increased across NLR quartiles: 2.27, 2.72, 3.26 and 4.54 per 100 person-years, respectively. Cox proportional hazard regression analysis adjusting for the individual CHA2 DS2 -VASc score risk factors showed that, compared with the lowest NLR quartile, the HR for stroke was 1.11 (95% CI, 0.91-1.35), 1.25 (1.03-1.51) and 1.56 (1.29-1.88) for the second, third and highest quartile, respectively. On stratified analysis, NLR refined the risk of stroke across all CHA2 DS2 -VASc score strata. Adding NLR to the CHA2 DS2 -VASc score increased the AUC from 0.627 (95% CI, 0.612-0.643) to 0.635 (0.619-0.651) (P = 0.037).

CONCLUSIONS

The neutrophil to lymphocyte ratio is directly associated with the risk of stroke in patients with atrial fibrillation. Future studies are needed to replicate these findings.

High prevalence of vitamin D deficiency and insufficiency in adolescent inpatients diagnosed with eating disorders

OBJECTIVE

Previous studies assessing vitamin D status in adolescents with eating disorders showed inconsistent results. The aim of the current study was to assess vitamin D status in a large cohort of adolescent inpatients with eating disorders and its relation to bone mineral density (BMD) and depression.

METHOD

25-Hydroxyvitamin D (25OHD), calcium, phosphorus, and alkaline phosphatase levels as well as BMD and depression were assessed on admission in 87 inpatients (aged 16 ± 2 years, females = 81) with eating disorders [anorexia nervosa (AN) = 64; bulimia nervosa (BN) = 5; eating disorders not otherwise specified-binge/purge type (EDNOS-B/P) = 18].

RESULTS

Mean 25OHD levels were 24.1 ± 7.5 ng/ml (25.0 ± 7.6, 25.4 ± 9.9, and 22.0 ± 9.9 ng/ml in patients with AB, BN, and EDNOS-B/P, respectively). Vitamin D deficiency (<15 ng/ml) was found in 7.8% of the patients, and insufficiency (15-20 ng/ml) in 22.2%. Only 16.7% had levels >32 ng/ml, considered optimal by some experts. No associations were found between 25OHD levels and BMD or comorbid depression. 25OHD levels during winter were significantly lower than summer levels (p < .001). Mean lumbar spine BMD z-score in patients with AN and EDNOS-B/P type was low (-1.5 ± 1.1) and correlated with body mass index standard deviation score (p = .03).

DISCUSSION

Adolescents with eating disorders show a high prevalence of vitamin D deficiency and insufficiency. Given the risk of osteoporosis in this population, 25OHD levels found in this group may not offer optimal bone protection. Vitamin D levels should be routinely checked and supplementation should be administered as required.

Vitamin D, Cancer Risk, and Mortality

Antiproliferative effects of 1,25-dihydroxyvitamin D, the biologically active form of vitamin D, are well established in various cell types by influencing cell differentiation and decreasing cell proliferation, growth, invasion, angiogenesis, and metastasis. Several meta-analyses showed that low serum levels of 25(OH)D was associated with colorectal cancer and overall mortality, while the association with cancer mortality was less consistent. VDR is a crucial mediator for the cellular effects of vitamin D and conflicting data have been reported for most malignancies. Beyond VDR, the biological effects of vitamin D are mediated by the vitamin D-binding protein. The GC (group-specific component) gene, encoding DBP, is highly polymorphic and several polymorphisms were investigated in association with cancer development with controversial results. Vitamin D supplementation was found to be associated with a reduced risk of overall mortality, reviewing all published trials on healthy subjects, whereas the evidence of an effect on cancer risk and mortality is less clear. Furthermore, long-term health effects of high doses of vitamin D, extended duration of supplementation, and the association with different baseline vitamin D levels remain to be investigated. In summary, epidemiological and preclinical studies support the development of vitamin D as preventative and therapeutic anticancer agents, with significant associations especially found for low vitamin D status with overall mortality and cancer outcome, more than cancer incidence. However, a definitive conclusion cannot be drawn and only large randomized clinical trials, both in healthy subjects and in cancer patients, will allow to draw definitive conclusions on the effect of vitamin D supplementation on cancer risk, prognosis, and mortality.

Associations of vitamin D deficiency with postoperative gait and mortality among patients with fractures of the proximal femur

Objective

To assess whether serum vitamin D concentration is associated with gait status and mortality among patients with fractures of the proximal femur, six months after suffering the fracture.

Methods

Consecutive patients aged ≥65 years with fractures of the proximal femur, who were admitted to the orthopedics and traumatology ward of our service between January and December 2011, were prospectively evaluated. Clinical, radiological, epidemiological and laboratory analyses were performed, including vitamin D. The patients underwent surgery and were followed up as outpatients, with return visits 15, 30, 60 and 180 days after discharge, at which the outcomes of gait and mortality were evaluated.

Results

Eighty-eight patients were evaluated. Two of them were excluded because they presented oncological fractures. Thus, 86 patients of mean age 80.2 ± 7.3 years were studied. In relation to serum vitamin D, the mean was 27.8 ± 14.5 ng/mL, and 33.7% of the patients presented deficiency of this vitamin. In relation to gait, univariate and multivariate logistic regression showed that vitamin D deficiency was not associated with gait recovery, even after adjustment for gender, age and type of fracture (OR: 1.463; 95% CI: 0.524–4.088; p = 0.469). Regarding mortality, Cox regression analysis showed that vitamin D deficiency was not related to its occurrence within six months, even in multivariate analysis (HR: 0.627; 95% CI: 0.180–2.191; p = 0.465).

Conclusion

Serum vitamin D concentration was not related to gait status and/or mortality among patients with fractures of the proximal femur, six months after suffering the fracture.

Calcium-phosphate and parathyroid intradialytic profiles: A potential aid for tailoring the dialysate calcium content of patients on different hemodialysis schedules

Severe hyperparathyroidism is a challenge on hemodialysis. The definition of dialysate calcium (Ca) is a pending issue with renewed importance in cases of individualized dialysis schedules and of portable home dialysis machines with low-flow dialysate. Direct measurement of calcium mass transfer is complex and is imprecisely reflected by differences in start-to-end of dialysis Ca levels. The study was performed in a dialysis unit dedicated to home hemodialysis and to critical patients with wide use of daily and tailored schedules. The Ca-phosphate (P)-parathyroid hormone (PTH) profile includes creatinine, urea, total and ionized Ca, albumin, sodium, potassium, P, PTH levels at start, mid, and end of dialysis. "Severe" secondary hyperparathyroidism was defined as PTH > 300 pg/mL for ≥3 months. Four schedules were tested: conventional dialysis (polysulfone dialyzer 1.8-2.1 m(2) ), with dialysate Ca 1.5 or 1.75 mmol/L, NxStage (Ca 1.5 mmol/L), and NxStage plus intradialytic Ca infusion. Dosages of vitamin D, calcium, phosphate binders, and Ca mimetic agents were adjusted monthly. Eighty Ca-P-PTH profiles were collected in 12 patients. Serum phosphate was efficiently reduced by all techniques. No differences in start-to-end PTH and Ca levels on dialysis were observed in patients with PTH levels < 300 pg/mL. Conversely, Ca levels in "severe" secondary hyperparathyroid patients significantly increased and PTH decreased during dialysis on all schedules except on Nxstage (P < 0.05). Our data support the need for tailored dialysate Ca content, even on "low-flow" daily home dialysis, in "severe" secondary hyperparathyroid patients in order to increase the therapeutic potentials of the new dialysis techniques.

The association between red cell distribution width and stroke in patients with atrial fibrillation

OBJECTIVE

Red cell distribution width is associated with increased risk of cardiovascular morbidity and mortality. We aimed to assess its association with stroke in patients with atrial fibrillation.

METHODS

By using the computerized database of the largest Health Maintenance Organization in Israel, we identified a cohort of adults with atrial fibrillation diagnosed before January 1, 2012. Eligible subjects were not taking anticoagulants at baseline and had at least 1 blood cell count performed in 2011 (41,140 subjects). The cohort was followed for the first occurrence of stroke until December 31, 2012.

RESULTS

Overall, 1692 subjects developed stroke during 38,024 person-years of follow-up (stroke rate, 4.45 per 100 person-years). Stroke incidence rate increased across red cell distribution width quartiles: 3.26, 3.71, 5.01, and 6.05 per 100 person-years in the lowest (≤ 13.4%), second (13.4%-14.1%), third (14.1%-15.0%), and highest (>15%) red cell distribution width quartiles, respectively. On multivariate analysis adjusting for Congestive heart failure, Hypertension, Age ≥ 75, Diabetes, and Prior Stroke or TIA (doubled) (CHADS2) score risk factors, the hazard ratio for stroke was 1.29 (95% confidence interval, 1.17-1.42) in subjects with red cell distribution width >14.5% compared with those with values ≤ 14.5% and was similar in subjects with and without anemia. When analyzed as quartiles, the hazard ratio for stroke was 1.33 (confidence interval, 1.15-1.53) in the highest quartile compared with the lowest quartile and was similar in subjects with and without anemia. The area under the receiver operating characteristic curve was 0.598 for (CHADS2) score and increased to 0.618 when red cell distribution width was included in the model (P < .001).

CONCLUSIONS

Red cell distribution width is directly associated with the risk of stroke regardless of anemia status and improves the predictive accuracy for stroke in patients with atrial fibrillation.

Increased low-density lipoprotein cholesterol level is associated with non-vertebral fractures in postmenopausal women

Although a high serum low-density lipoprotein cholesterol (LDL-C) level is an established risk factor for atherosclerosis, it is unclear whether it is associated with osteoporosis. In this study, the associations between the serum LDL-C level and bone mineral density (BMD), bone metabolic markers, and the presence of prevalent vertebral or non-vertebral fractures were examined. A total of 211 healthy postmenopausal women (age range, 46-80 years) who visited a community health center were recruited consecutively. Their radiographic and biochemical characteristics were collected. Prevalent vertebral and non-vertebral fractures were found in 49 (23.2%) and 36 (17.1%) subjects, respectively. Simple regression analyses showed that the serum LDL-C level was not significantly correlated with lumbar or femoral BMD or serum levels of total amino-terminal propeptide of type I collagen (PINP) or carboxy-terminal telopeptide of type I collagen (CTX). Logistic regression analyses adjusted for age and BMI showed that the increased serum LDL-C level was selected as an index affecting the presence of prevalent non-vertebral fractures, but not vertebral fractures. This result was still significant after additional adjustments for years since menopause, physical activity, previous cardiovascular events, bone markers, BMD, serum Ca, P, Cr, 25(OH)D, grip strength, tandem gait test, and use of drugs for hyperlipidemia [odds ratio 1.76 (1.13-2.73), p=0.012]. These findings suggest that a high serum LDL-C level may be a risk factor for prevalent non-vertebral fragility fractures independent of bone turnover, bone mass, vitamin D insufficiency, or frail status in postmenopausal women, and that it may be detrimental to bone, as well as blood vessels.

A prospective observational study of all-cause mortality in relation to serum 25-OH vitamin D3 and parathyroid hormone levels in patients with type 2 diabetes

BACKGROUND

Low levels of vitamin D have been related to increased mortality and morbidity in several non-diabetic studies. We aimed to prospectively study relationships between serum 25-OH vitamin D3 (vitamin D) and of serum parathyroid hormone (PTH) to total mortality in type 2 diabetes. We also aimed to compare the levels of these potential risk-factors in patients with and without diabetes.

METHODS

The main study design was prospective and observational. We used baseline data from 472 men and 245 women who participated in the "Cardiovascular Risk factors in Patients with Diabetes-a Prospective study in Primary care" study. Patients were 55-66 years old at recruitment, and an age-matched non-diabetic sample of 129 individuals constituted controls for the baseline data. Carotid-femoral pulse-wave velocity (PWV) was measured with applanation-tonometry and carotid intima-media thickness (IMT) with ultrasound. Patients with diabetes were followed for all-cause mortality using the national Swedish Cause of Death Registry.

RESULTS

Levels of vitamin D were lower in patients with diabetes than in controls, also after correction for age and obesity, while PTH levels did not differ. Nine women and 24 men died during 6 years of median follow up of the final cohort (n = 698). Vitamin D levels were negatively related to all-cause mortality in men independently of age, PTH, HbA1c, waist circumference, 24-h systolic ambulatory-blood pressure (ABP) and serum-apoB (p = 0.049). This finding was also statistically significant when PWV and IMT were added to the analyses (p = 0.028) and was not affected statistically when medications were also included in the regression-analysis (p = 0.01). In the women with type 2 diabetes, levels of PTH were positively related with all-cause mortality in the corresponding calculations (p = 0.016 without PWV and IMT, p = 0.006 with PWV and IMT, p = 0.045 when also adding medications to the analysis), while levels of vitamin D was without statistical significance (p >0.9).

CONCLUSIONS

Serum vitamin D in men and serum PTH in women give prognostic information in terms of total-mortality that are independent of regular risk factors in addition to levels of ABP, IMT and PWV.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01049737.

Obesity and association of serum 25(OH)D levels with all-cause mortality

Sequestration of vitamin D in adipose tissue is the main cause of the lower serum 25(OH)D levels in obese subjects. However, it remains unknown whether the adipose tissue stores of vitamin D are readily mobilized for meeting body needs. We aimed to examine whether the association between serum 25(OH)D and all-cause mortality differs by body weight. Using the computerized database of the largest health care provider in Israel, we identified a cohort of subjects ≥20-years old with serum 25(OH)D levels measured between January 2008 and December 2009. Mortality was ascertained through April-2013. Cox regression with restricted cubic-spline function was used to assess the association between serum 25(OH)D and mortality. Median follow-up was 48 months (IQR 43-53 months); 12,337 of 175,781 participants (7.0 %) died. The association between 25(OH)D and mortality was not linear (P < 0.001), and differed between BMI categories (P = 0.019). The lowest adjusted risk for mortality was observed at serum 25(OH)D levels of 73.0, 68.0, and 66.5 nmol/L among subjects with BMI <25, 25-29.9, and ≥30 kg/m(2), respectively. Compared to reference level of 75 nmol/L, increased adjusted HR as evident by 95 % confidence interval lower bound >1.0 was observed at serum 25(OH)D levels less than; 61.0, 48.0, and 40.0 nmol/L among subjects with BMI <25, 25-29.9, and ≥30 kg/m(2), respectively. Serum 25(OH)D levels associated with increased all-cause mortality were inversely related to BMI. However, this observational cohort study may still suffer from residual confounding; therefore, cause and effect relationship cannot be established from this study.

Influence of vitamin D status on the effect of statins on bone mineral density and bone turnover markers in postmenopausal women

OBJECTIVE

This study sought to assess whether the association between statin use and bone mineral density (BMD) and bone turnover markers is modulated by serum 25-hydroxyvitamin D (25OHD) levels in postmenopausal women. Design, Participants, and Settings: Approximately 1422 postmenopausal women were recruited from the Camargo Cohort after excluding those with any known medical disorder or drug that might affect bone metabolism. Participants were categorized into four groups: 25OHD levels of 20 ng/mL or less and not taking statins (group 1; n = 492); 25OHD levels greater than 20 ng/mL and on statins (group 2; n = 143); 25OHD levels of 20 ng/mL or less and using statins (group 3; n = 112); and 2OHD levels greater than 20 ng/mL and non-statin use (group 4; n = 675). Multivariate analyses were performed to compare BMD and bone turnover markers between groups.

RESULTS

Women in group 2 had an adjusted femoral neck and total hip BMD higher than women in group 1 (P < .0001 and P = .003, respectively). A trend toward a significant difference was observed regarding lumbar BMD (P = .08). Serum aminoterminal propeptide of type 1 collagen and C-terminal telopeptide of type 1 collagen levels were lower in group 2 than in group 1, in crude and adjusted models, although only serum C-terminal telopeptide of type 1 collagen difference was significant (P = .009).

CONCLUSIONS

Women on statins and serum 25OHD levels above 20 ng/mL have greater BMD and less bone resorption than those without either of the factors. Differences, however, are not significant in women with only one of them. Vitamin D and statins seem to interact positively in their effects on bone metabolism.

Statins use and risk of mortality in patient with Clostridium difficile infection

Current evidence suggests that statins may improve outcome in infectious diseases. This study aims to assess whether statins use is associated with reduced risk of 30-day mortality in Clostridium difficile infection (CDI). Using the computerized database of Clalit, the largest healthcare provider in Israel, we identified a cohort of adult subjects (age ≥40 years) who tested positive on a C. difficile toxin assay performed between January 2011 and December 2012. Subjects were defined as current statins users if they filled at least one prescription during the 90 days before the laboratory assay date. Current users were classified into long-term users if at least one additional prescription was filled during the previous 91-180 days; otherwise they were defined as short-term users. A total 1888 patients with CDI were included. Of them, 340 (18.0%) died during the first 30 days after diagnosis. The 30-day mortality rate was lower among current statins users 89/669 (13.3%) compared with 251/1219 (20.6%) in non-users (p <0.001). A significant reduced risk of 30-day mortality existed after adjustment for potential confounders; adjusted OR = 0.57 (95% CI 0.42-0.79) and was unique to long-term users; 0.53 (0.38-0.73) but not short-term users; 1.15 (0.56-2.34). The risk of 30-day mortality decreased with increasing number of filled statins prescriptions; adjusted OR = 0.77 (95% CI 0.67-0.89) for each additional prescription. Current aspirin use was also independently associated with reduced mortality; adjusted OR = 0.64 (95% CI 0.43-0.88). In conclusion, current statins use, particularly long-term use, has a dose-response protective effect on mortality in patients with CDI.

Meta-analysis of all-cause mortality according to serum 25-hydroxyvitamin D

We examined the relationship between serum 25-hydroxyvitamin D (25[OH]D) and all-cause mortality. We searched biomedical databases for articles that assessed 2 or more categories of 25(OH)D from January 1, 1966, to January 15, 2013. We identified 32 studies and pooled the data. The hazard ratio for all-cause mortality comparing the lowest (0-9 nanograms per milliliter [ng/mL]) to the highest (> 30 ng/mL) category of 25(OH)D was 1.9 (95% confidence interval = 1.6, 2.2; P < .001). Serum 25(OH)D concentrations less than or equal to 30 ng/mL were associated with higher all-cause mortality than concentrations greater than 30 ng/mL (P < .01). Our findings agree with a National Academy of Sciences report, except the cutoff point for all-cause mortality reduction in this analysis was greater than 30 ng/mL rather than greater than 20 ng/mL.

CHA2DS2-VASc score is directly associated with the risk of pulmonary embolism in patients with atrial fibrillation

BACKGROUND

The risk stratification score, which includes Congestive heart failure, Hypertension, Age ≥ 75 [doubled], Diabetes, Stroke [doubled]- Vascular disease, Age 65-74, and Sex category [female] (CHA2DS2-VASc), is used to predict stroke in atrial fibrillation. However, whether high CHA2DS2-VASc score carries a higher risk of pulmonary embolism remains unknown. We aimed to investigate the association between the severity of CHA2DS2-VASc score and the incidence of pulmonary embolism.

METHODS

A total of 73,541 adults with atrial fibrillation diagnosed before January 1, 2012, and no history of pulmonary embolism, were retrospectively identified from the computerized database of the Clalit Health Services, which is the largest not-for-profit health maintenance organization in Israel. The CHA2DS2-VASc score was calculated for each subject at study entry. The cohort was followed for the first occurrence of pulmonary embolism until December 31, 2012 (70,210 person-years).

RESULTS

Pulmonary embolism developed in 158 subjects, representing an incidence of 225.0 per 100,000 person-years. The incidence of pulmonary embolism increased with increasing CHA2DS2-VASc score (P < .001). On Cox proportional analysis, CHA2DS2-VASc score was significantly associated with pulmonary embolism (hazard ratio, 1.22; 95% confidence interval [CI], 1.13-1.32) for a 1-point increase in CHA2DS2-VASc score. The results were similar after adjusting for anticoagulants and antiplatelet use (hazard ratio, 1.24; 95% CI, 1.14-1.34), and remained unchanged after further adjustment for active malignancy. The predictive values for pulmonary embolism were similar for CHA2DS2-VASc score and the classic risk stratification score which includes Congestive heart failure, Hypertension, Age >75 years, Diabetes, and Stroke [doubled] (CHADS2); the areas under the receiver operating characteristic curves were 0.619 (95% CI, 0.579-0.660) and 0.616 (95% CI, 0.575-0.656), respectively.

CONCLUSIONS

CHA2DS2-VASc score is directly associated with the incidence of pulmonary embolism in atrial fibrillation.

Changes in blood pressure and lipid levels in young women consuming a vitamin D-fortified skimmed milk: a randomised controlled trial

Vitamin D exerts a variety of extra-skeletal functions.

AIM

to know the effects of the consumption of a vitamin D-fortified skimmed milk on glucose, lipid profile, and blood pressure in young women.

METHODS

a randomised, placebo-controlled, double-blind parallel-group trial of 16 weeks duration was conducted in young women with low iron stores who consumed a skimmed milk fortified with iron and 200 IU/day (5 μg) of vitamin D (D-fortified group, n = 55), or a placebo without vitamin D (D-placebo group, n = 54). A reference group (n = 56) of iron-sufficient women was also recruited.

RESULTS

baseline serum 25-hydroxyvitamin D was inversely correlated with total-cholesterol (r = -0.176, p = 0.023) and low density lipoprotein-cholesterol (LDL-chol) (r = -0.176, p = 0.024). During the assay, LDL-cholesterol increased in the D-placebo group (p = 0.005) while it tended to decrease in the D-fortified group (p = 0.07). Neither group displayed changes in total-cholesterol, high density lipoprotein-cholesterol (HDL-chol), triglycerides or glucose levels. Systolic (p = 0.017) and diastolic (p = 0.010) blood pressure decreased during the assay in the D-fortified group without significant differences compared to the D-placebo.

CONCLUSION

consumption of a dairy product fortified with vitamin D reduces systolic and diastolic blood pressure but does not change lipid levels in young women.

Effect of a single oral dose of 600,000 IU of cholecalciferol on muscle strength: a study in young women

BACKGROUND

The effect of a single large oral dose of vitamin D on muscle function in young people with vitamin D deficiency has not been investigated so far.

AIM

We evaluated the effect of a single oral dose of 600,000 IU of cholecalciferol on muscle strength.

SUBJECTS AND METHODS

Eighteen young women with vitamin D deficiency received a single oral dose of 600,000 IU of cholecalciferol. We evaluated changes in maximal voluntary contraction (MVC) and speed of contraction (S) in response to cholecalciferol by using an hand held dynamometer at 3, 15, 30, 60 and 90 days, compared to baseline.

RESULTS

We observed no significant change in MVC and S values, a significant increase of 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)2D] and a significant decrease in serum parathyroid hormone (PTH) (p<0.001 for all). A significant correlation was found between MVC and S and serum phosphorus (P) after supplementation (p<0.02 and p<0.05, respectively). Conversely, we observed no association between the parameters of muscle strength and 25(OH)D, ionized calcium (Ca2+), PTH and 1,25(OH)2D.

CONCLUSIONS

A single dose of 600,000 IU of cholecalciferol does not directly enhance handgrip strength in young women with vitamin D deficiency. More studies are needed on the indirect effect of the hormone on muscle.

Hypovitaminosis D in the Middle East and North Africa: Prevalence, risk factors and impact on outcomes

BACKGROUND

The Middle East and North Africa (MENA) region registers some of the highest rates of hypovitaminosis D worldwide.  

AIM

We systematically reviewed the prevalence of hypovitaminosis D, rickets and osteomalacia, their predictors and impact on major outcomes, in the region.

METHODS

Medline, Pubmed and Embase search engines, entering keywords and concepts, combined with individual countries of interest, were used. Search was limited years 2000-2012; and review articles were used for the period preceding year 2000.

RESULTS

Rickets and osteomalacia still occur in this sunny region. Hypovitaminosis D prevails, with rates varying 30-90%, considering a desirable serum 25 hydroxy-vitamin D [25(OH)D] of 20 ng/ml. Advancing age, female gender, multi-parity, clothing style, season, socio-economic status and urban living are recognized predictors of hypovitaminosis D in adults. Prolonged breastfeeding without vitamin D supplementation and low dietary calcium intake are the recognized risk factors for rickets and hypovitaminosis D in children.. Associations with pain score and disease activity in rheumatologic disorders, viral load and interleukins in hepatitis C, BMI, lipids and insulin sensitivity, blood pressure, heart failure and mortality are described. Sun exposure in adults decreased prevalence of metabolic syndrome in one study. Few randomized vitamin D trials revealed that the majority of mothers or children failed to achieve a desirable 25(OH)D level, even with doses by far exceeding current recommendations. A trial in adolescent girls reveals substantial bone and lean mass increments.

CONCLUSION

Hypovitaminosis D is prevalent in MENA. The lack of populations based studies, gaps in studies in infants, pre-pubertal children and pregnant women, hinder the development of region specific guidelines and constitute a major obstacle to impact this chronic and most often subclinical disease.

Inverse association between circulating vitamin D and mortality--dependent on sex and cause of death?

BACKGROUND AND AIMS

In various populations, vitamin D deficiency is associated with chronic diseases and mortality. We examined the association between concentration of circulating 25-hydroxyvitamin D [25(OH)D], a marker of vitamin D status, and all-cause as well as cause-specific mortality.

METHODS AND RESULTS

The study included 3404 participants of the general adult Swiss population, who were recruited between November 1988 and June 1989 and followed-up until the end of 2008. Circulating 25(OH)D was measured by protein-bound assay. Cox proportional hazards regression was used to examine the association between 25(OH)D concentration and all-cause and cause-specific mortality adjusting for sex, age, season, diet, nationality, blood pressure, and smoking status. Per 10 ng/mL increase in 25(OH)D concentration, all-cause mortality decreased by 20% (HR = 0.83; 95% CI 0.74-0.92). 25(OH)D concentration was inversely associated with cardiovascular mortality in women (HR = 0.68, 95% CI 0.46-1.00 per 10 ng/mL increase), but not in men (HR = 0.97; 95% CI 0.77-1.23). In contrast, 25(OH)D concentration was inversely associated with cancer mortality in men (HR = 0.72, 95% CI 0.57-0.91 per 10 ng/mL increase), but not in women (HR = 1.14, 95% CI 0.93-1.39). Multivariate adjustment only slightly modified the 25(OH)D-mortality association.

CONCLUSION

25(OH)D was similarly inversely related to all-cause mortality in men and women. However, we observed opposite effects in women and men with respect to cardiovascular and cancer mortality.

Low vitamin D status is an independent predictor of increased frailty and all-cause mortality in older men: the Health in Men Study

CONTEXT AND OBJECTIVE

Hypovitaminosis D and frailty are common in the older population. We aimed to determine whether 25-hydroxyvitamin D [25(OH)D] concentrations are associated with frailty and mortality.

DESIGN

We conducted a prospective cohort study.

SETTING AND PARTICIPANTS

Participants included 4203 older men aged 70-88 years in Perth, Western Australia.

MAIN OUTCOME MEASURES

25(OH)D was measured by immunoassay. Frailty was assessed with the 5-point FRAIL (fatigue, resistance, ambulation, illness, and loss of weight) scale. Mortality was determined from the death registry via the Western Australian Data Linkage System.

RESULTS

At baseline, 676 (16.1%) men were frail, as defined by having ≥3 deficits (FRAIL scale ≥ 3). In multivariate cross-sectional analysis, low vitamin D status, defined by the lowest quartile of 25(OH)D values (<52.9 nmol/L), was associated with increased prevalent frailty (odds ratio, 1.96; 95% confidence interval [CI], 1.52 to 2.52) in comparison to the highest quartile of 25(OH)D values (>81.6 nmol/L). After a mean period of 5.3 years, the adjusted odds ratio of being frail at follow-up for men with low vitamin D and having zero deficit at baseline (FRAIL scale = 0) was 1.56 (95% CI, 1.07 to 2.27). Low vitamin D also predicted all-cause mortality over a period of up to 9.2 years (hazard ratio, 1.20; 95% CI, 1.02 to 1.42), independent of baseline frailty and other covariates.

CONCLUSION

Hypovitaminosis D is associated with prevalent and incident frailty in older men. Hypovitaminosis D also predicts all-cause mortality, independent of frailty. The association between vitamin D and mortality is not solely dependent on the occurrence of frailty.

Is there a reverse J-shaped association between 25-hydroxyvitamin D and all-cause mortality? Results from the U.S. nationally representative NHANES

CONTEXT

A reverse J-shaped association between serum 25-hydroxyvitamin D (25[OH]D) concentration and all-cause mortality was suggested in a 9-year follow-up (1991-2000) analysis of the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994).

OBJECTIVE

Our objective was to repeat the analyses with 6 years additional follow-up to evaluate whether the association persists through 15 years of follow-up.

PARTICIPANTS

The study included 15 099 participants aged ≥ 20 years with 3784 deaths.

MAIN OUTCOME MEASURE

Relative risk (RR) of death from all causes was adjusted for age, sex, race/ethnicity, and season using 2 Poisson regression approaches: traditional categorical and cubic splines. Results were given for 9 25(OH)D levels: <20, 20 to 29, 30 to 39, 40 to 49, 50 to 59, 60 to 74, 75 to 99 (reference), 100 to 119, and ≥ 120 nmol/L.

RESULTS

The reverse J-shaped association became stronger with longer follow-up and was not affected by excluding deaths within the first 3 years of follow-up. Similar results were found from both statistical approaches for levels <20 through 119 nmol/L. Adjusted RR (95% confidence interval [CI]) estimates for all levels <60 nmol/L were significantly >1 compared with the reference group. The nadir of risk was 81 nmol/L (95% CI, 73-90 nmol/L). For 25(OH)D ≥ 120 nmol/L, results (RR, 95% CI) were slightly different using traditional categorical (1.5, 1.02-2.3) and cubic splines approaches (1.2, 0.9-1.4). The association appeared in men, women, adults ages 20 to 64 years, and non-Hispanic whites but was weaker in older adults. The study was too small to evaluate the association in non-Hispanic black and Mexican-American adults.

CONCLUSIONS

A reverse J-shaped association between serum 25(OH)D and all-cause mortality appears to be real. It is uncertain whether the association is causal.

Association of vitamin D deficiency with incidence of type 2 diabetes in high-risk Asian subjects

BACKGROUND

Recent studies suggest an association between 25-hydroxyvitamin D [25(OH)D] and type 2 diabetes (T2D) risk. However, prospective studies investigating the relation between vitamin D inadequacy and incidence of T2D incorporating obesity and dynamic measures of insulin resistance (IR) and pancreatic β cell function are limited.

OBJECTIVE

We tested the hypothesis that baseline 25(OH)D is associated with the incidence of T2D in high-risk subjects for up to 5 y of follow-up, independently of obesity, baseline IR, and β cell function.

DESIGN

We recruited 1080 nondiabetic Korean subjects [mean ± SD age: 49.5 ± 11.4 y] based on the presence of one or more risk factors for T2D, including obesity, hypertension, dyslipidemia, and/or family history of T2D. We measured anthropometric and biochemical indicators, HOMA2-IR, and the insulinogenic index (IGI; calculated as change in insulin at 30 min/change in glucose at 30 min) from a 75-g oral-glucose-tolerance test.

RESULTS

Of the participants, 10.5% had a serum 25(OH)D deficiency (<10 ng/mL), 51.6% had an insufficiency (10.0-19.9 ng/mL), and 38.0% had a sufficiency (≥20 ng/mL), and the incidence of T2D at 32.3 ± 15.6 mo (±SD) declined accordingly: 15.9%, 10.2%, and 5.4%, respectively (P < 0.001). After adjustment for age, sex, blood pressure, lifestyles, family history, season, parathyroid hormone, and high-sensitivity C-reactive protein, the participants with 25(OH)D deficiency had an increased risk of T2D independently of BMI, HOMA2-IR, and IGI; the HRs were 2.06 (95% CI: 1.22, 3.49) for 25(OH)D 10-19.9 ng/mL compared with ≥20 ng/mL and 3.23 (95% CI: 1.66, 6.30) for 25(OH)D <10 ng/mL compared with ≥20 ng/mL.

CONCLUSION

The current prospective study suggests that vitamin D metabolism may play a role in T2D pathogenesis independently of known risk factors. This trial was registered at clinicaltrials.gov as NCT01508481.

Vitamin D and overall mortality

Vitamin D is a steroid molecule, mainly produced in the skin that regulates the expression of a large number of genes. Several meta-analyses of epidemiological studies support the evidence that low vitamin D serum level, which is highly prevalent worldwide, could be a 'new' risk factor for many chronic diseases including cancer, and for all-cause mortality. A meta-analysis in healthy subjects suggested that current doses of vitamin D supplements could be associated with decrease in total mortality rates. However, these associations are insufficient to establish causality between vitamin D and all-cause mortality. Furthermore, long-term health effects of high doses of vitamin D, that is, prolonged supplementation and association with different baseline vitamin D levels, remain to be investigated. Several trials are ongoing but population-based, placebo-controlled randomized trials with total mortality as the main endpoint should be planned to confirm a real beneficial effect of vitamin D for non-skeletal diseases and to prove causality.