Vitamin D insufficiency in North America

Association between serum vitamin D level and Graves' disease: a systematic review and meta-analysis

OBJECTIVE

This meta-analysis aims to analyze the relationship between serum vitamin D (VD) levels and Graves' disease (GD).

METHODS

We conducted a search for publications on VD and GD in the English language. Our search encompassed databases such as PubMed, Embase, Web of Science, and the Cochrane Library, covering publications available through August 2023. A meta-analysis was performed using Cochrane RevMan 5.4 software. The standardized mean difference (SMD) and 95% confidence interval (CI) were used for outcome calculation. We used R software to test for publication bias.

RESULTS

Twelve studies were selected, comprising 937 (22.4%) cases with GD and 3254 (77.6%) controls. The overall meta-analysis revealed that patients with GD are significantly more likely to have low VD levels (SMD = - 0.66; 95% CI: -1.05, - 0.27; p = 0.001) than those in the control group. Egger's test results indicated no publication bias (p = 0.0791). These studies exhibited a high degree of heterogeneity (chi-square = 205.86, p < 0.00001; I2 = 95%). Subgroup analysis was conducted based on assay method, geographic location, and mean age of the case group to explore the heterogeneity sources. Assay methods and geographic locations were identified as potential heterogeneity sources. Based on the mean age, there were no statistically significant differences found in the subgroup analysis of the included studies.

CONCLUSION

There is promising evidence that low serum VD levels may increase the risk of GD. Further rigorous and long-term trials are needed to explore the role of VD in the onset and treatment of GD.

Influence of Vitamin D Deficiency on the Expression of Genes and Proteins in Patients With Medium Rotator Cuff Tears

BACKGROUND

Whether vitamin D deficiency is related to rotator cuff muscle and tendon physiology is controversial.

PURPOSE

To assess the relationship between vitamin D deficiency and various gene expression patterns in patients with rotator cuff tears.

STUDY DESIGN

Controlled laboratory study.

METHODS

During arthroscopic surgery, samples from the supraspinatus muscle, deltoid muscle, and supraspinatus tendon were acquired from 12 patients with vitamin D deficiency (serum 25-hydroxyvitamin D concentration <20 ng/dL) and 12 patients with sufficient vitamin D levels (control group, serum 25-hydroxyvitamin D concentration ≥30 ng/dL) who were matched for age, sex, and tear size. Alterations in the expression of genes and proteins associated with myogenesis, muscle atrophy, adipogenesis, inflammation, and apoptosis, as well as in vitamin D receptor expression, were assessed using quantitative reverse transcription polymerase chain reaction, Western blotting, and immunohistochemistry and were compared between the 2 groups.

RESULTS

Vitamin D receptor gene expression in the deltoid muscle was significantly lower in the vitamin D deficiency group than in the control group (P = .043). Additionally, in the deltoid muscle, myoDgene expression levels were lower and atrogin levels were higher in the vitamin D deficiency group than in the control group (P = .034 and P = .011, respectively). However, in the supraspinatus muscle, no differences were observed between groups in the expression of myogenesis- or atrophy-related genes (all P > .05). The expression of inflammation-related genes (interleukin (IL)-1β and IL-6) was significantly higher in the vitamin D deficiency group, in both the deltoid and supraspinatus muscles (all P < .05). The supraspinatus tendon tissue did not show any significant differences in any gene expression evaluated (all P > .05). A correlation between gene and protein expression was observed for atrogin and IL-1β in the deltoid muscle (P = .019 and P = .037, respectively) and for IL-6 in the supraspinatus muscle (P = .044).

CONCLUSION

Vitamin D deficiency was not associated with the expression of myogenesis-related or muscle atrophy-related genes in the supraspinatus muscle of patients with rotator cuff tears, unlike in the deltoid muscle; rather, vitamin D deficiency was associated with increased proinflammatory cytokine expression.

CLINICAL RELEVANCE

In patients with rotator cuff tears, vitamin D deficiency was observed to be associated with increased levels of proinflammatory cytokines in the rotator cuff muscles, without significant changes in gene expression related to myogenesis or muscle atrophy.

Assessment of vitamin D among male adolescents and young adults hospitalized with eating disorders

PURPOSE

Medical complications of eating disorders in males are understudied compared to females, as is the case of vitamin D deficiency. The aim of this study was to assess vitamin D levels among male and female adolescents and young adults hospitalized for medical complications of eating disorders.

METHODS

We retrospectively reviewed electronic medical records of patients aged 9-25 years (N = 565) admitted to the University of California, San Francisco Eating Disorders Program for medical instability, between May 2012 and August 2020. Serum vitamin D (25-hydroxy) level was assessed at admission as was history of prior calcium, vitamin D, or multivitamin supplementation. Linear regression was used to assess factors associated with vitamin D levels.

RESULTS

A total of 93 males and 472 females met eligibility criteria (age 15.5 ± 2.8, 58.8% anorexia nervosa; admission body mass index 17.6 ± 2.91). Among male participants, 44.1% had 25-hydroxyvitamin D levels < 30 ng/mL, 18.3% had 25-hydroxyvitamin D levels < 20 ng/mL, and 8.6% had 25-hydroxyvitamin D levels < 12 ng/mL. There were no significant differences in 25-hydroxyvitamin D levels in males compared to females, except that a lower proportion (1.9%) of female participants had 25-hydroxyvitamin D levels < 12 ng/mL (p = 0.001). Only 3.2% of males reported calcium or vitamin D-specific supplementation prior to hospital admission, while 8.6% reported taking multivitamins. White race, prior calcium/vitamin D supplementation, and higher calcium levels were associated with higher vitamin D levels on admission.

CONCLUSIONS

Nearly half of patients admitted to the hospital for malnutrition secondary to eating disorders presented with low 25-hydroxyvitamin D levels; males were more likely than females to have severe vitamin D deficiency. These findings support vitamin D assessment as part of the routine medical/nutritional evaluation for hospitalized eating disorder patients, with particular attention on male populations.

Prevalence of and Factors Associated With Nutritional Supplement Use Among Older Chinese Adults: A Nationwide Cross-Sectional Study in China

Objective

This study identified the prevalence of nutritional supplement (NS) use among older Chinese adults and explored the factors associated with NS use in this population.

Methods

We used data from 11,089 Chinese men and women aged ≥ 65 years from the 2018 Chinese Longitudinal Healthy Longevity Survey. The chi-square test was used to examine the differences in demographics, health status and lifestyles at different levels. Multivariate logistic regression was used to assess the association between NS use and demographic and lifestyle characteristics.

Results

Twelve percent of Chinese adults aged 65 years and above used NS. In terms of the type of supplement used, the most commonly used was calcium (8.49%), followed by protein (2.73%) and multivitamins (2.40%). In terms of demographic characteristics, women, older people, urban residents with other marital status, higher educational level, better living conditions and better lifestyle habits showed a greater use of some kinds of NS to varying degrees. Factors associated with the use of any NS included female gender [OR = 1.71, 95% confidence intervals (95% CI): 1.09-1.44], age 85-94 (OR = 1.30, 95% CI: 1.08-1.58), urban household registration (hukou) (OR = 1.25, 95% CI:1.46-2.00), higher education (primary school and middle school: OR = 1.32, 95% CI:1.14-1.52; high school and above: OR = 1.56, 95% CI:1.25-1.94), average and poor living standard (average: OR = 0.64, 95% CI:0.56-0.73; poor: OR = 0.42, 95% CI:0.32-0.55), poor health status (OR = 1.36, 95% CI:1.13-1.63), former smoking (OR = 1.33, 95% CI:1.11-1.60), and having exercise habits (former exercise: OR = 2.24, 95% CI:1.83-2.74; current exercise: OR = 2.28, 95% CI:2.00-2.61). Women reported taking 2-3 kinds of NSs, and more than 50% of NS users reported taking supplements often.

Conclusion

This study provides information on the current prevalence of NS use among older Chinese adults, and it clarifies the association of NS use with demographic, lifestyle and other factors. Providing scientifically based health guidance on NS use for older people is crucial to promoting their health.

Inhibition of Antiestrogen-Promoted Pro-Survival Autophagy and Tamoxifen Resistance in Breast Cancer through Vitamin D Receptor

We determined how vitamin D receptor (VDR) is linked to disease outcome in estrogen receptor-positive (ER+) breast cancer patients treated with tamoxifen (TAM). Breast cancer patients (n = 581) in four different datasets were divided into those expressing higher (above median) and lower levels of VDR in pretreatment ER+ tumors. Across all datasets, TAM-treated patients with higher pretreatment tumor VDR expression exhibited significantly longer recurrence-free survival. Ingenuity pathway analysis identified autophagy and unfolded protein response (UPR) as top differentially expressed pathways between high and low VDR-expressing ER+ cancers. Activation of VDR with vitamin D (VitD), either calcitriol or its synthetic analog EB1089, sensitized MCF-7-derived, antiestrogen-resistant LCC9 human breast cancer cells to TAM, and attenuated increased UPR and pro-survival autophagy. Silencing of VDR blocked these effects through the IRE1α-JNK pathway. Further, silencing of VDR impaired sensitivity to TAM in antiestrogen-responsive LCC1 cells, and prevented the effects of calcitriol and EB1089 on UPR and autophagy. In a preclinical mouse model, dietary VitD supplementation induced VDR activation and reduced carcinogen-induced ER+ mammary tumor incidence. In addition, IRE1α-JNK signaling was downregulated and survival autophagy was inhibited in mammary tumors of VitD-supplemented mice. Thus, activation of VDR is predictive of reduced risk of breast cancer recurrence in ER+ patients, possibly by inhibiting antiestrogen-promoted pro-survival autophagy.

Low Vitamin D Serum Levels in a Cohort of Myasthenia Gravis Patients in Argentina

There are limited and controversial studies that address the role of vitamin D (vitD), a vitamin with immunomodulatory effects, in myasthenia gravis (MG), a neuromuscular autoimmune disease. We aimed to assess 25-hydroxy vitamin D (25(OH)D) levels and to evaluate possible associations with the clinical severity and other biomarkers of the disease. Serum levels of 25(OH)D, anti-acetylcholine receptor antibodies and complement factor C5a were measured in MG patients (n = 66) and healthy volunteers (HV) (n = 25). Participants were evaluated through questionnaires to determine vitD intake and sunlight exposure. Severity scores were registered for MG patients. We found an 89.4% of MG individuals with nonsufficient levels of vitD, in comparison with 68.0% in the group of HV (OR = 3.96; P = 0.024). In addition, there was an inverse correlation between 25(OH)D levels and one of the scores (P = 0.037 r = -0.26, CI₉₅  = -0.49 to -0.0087). However, when we compared 25(OH)D median serum levels between MG patients and HV, no statistically significant differences have been found. This is the first report of vitD status in a cohort of Argentinean MG patients, where we found that patients are more likely to have nonsufficient levels of vitD compared to healthy people and that patients with more severe disease have lower levels of vitD.

Vitamin D status in preschool children in Algeria

It is well established today that an optimal vitamin D intake plays a crucial role in the constitution of optimal osseous mass during childhood, and hence in the prevention of the osteoporosis in adults. The prevalence of the vitamin D deficiency is increasing globally and Algeria is no exception in this regard. Our study is the first to be carried out with healthy children of preschool age in North Africa.

AIMS

The study aimed to evaluate the vitamin D status of a pediatric population, during all four seasons of the year, living in the north of Algeria, as well as to estimate the prevalence of vitamin D deficiency, identifying the potential risk factors.

MATERIAL AND METHODS

This was an analytic and cross-sectional study carried out between March 2014 and March 2016 with healthy preschool infants from an urban environment in the town of Hussein Dey. A total of 1016 infants aged 9-72 months were included during this period. The consensual threshold value was 20ng/mL.

RESULTS

The sex ratio was of 1.47 (535 boys/481 girls) and the average age of the children was 36.5±1.79 months. The daily average calcium ratio was 395±23 mg/with food contributions in vitamin D at an estimated average of 164 UI/day (4.1μg/day). The average concentration of the total 25-OHD for all four seasons of the year was 18.6±10.4ng/mL with an average rate of parathyroid hormone (PTH) of 30.9±14.6pg/mL. There was a highly significant inverse correlation between the serum level of vitamin D and PTH (r=-0.57; P=0.0001), the point of inflection was situated at 34.1ng/mL. The prevalence of vitamin D deficiency follows a seasonal variation that is statistically significant (P=0.0001), and the prevalence is higher during the autumn-winter period. The risk factors identified by multiple logistic regression were autumn-winter season (OR: 7; 95% CI: 3-11; P=0.001), age less than 24 months (OR: 3.8; 95% CI: 3.4-4.4; P=0.0001), high body mass index (OR: 2; 95% CI: 1.2-3.2; P=0.3), darker skin pigmentation (OR: 2.8; 95% CI: 2.2-5.2; P=0.001), duration of sunlight exposure less than 15min (OR: 6.1; 95% CI: 3.6-10.2; P=0.0001), low socioeconomic status (OR: 3.9; 95% CI: 1.5-4.3; P=0.01), calcium intake lower than 500 mg/day (OR: 2.5; 95% CI: 1.8-6; P=0.001), and a weekly dietary intake of vitamin D lower than 200 UI (OR: 2.6; 95% CI: 1.6-4.2; P=0.02).

DISCUSSION

No studies have been conducted in north Africa or Algeria concerning healthy preschool children; however, this population has a rapid growth rate and deserves special attention. The prevalence of vitamin D deficiency in the children of this study was higher than that reported in studies of children of the same age living in Europe or America, despite the fact that Algeria is closer to the equator (36° latitude north).

CONCLUSION

The changes experienced by Algerian society and the shorter exposure of the population to the sun call for more efforts regarding the detection and treatment of vitamin D deficiency, as well as an update of the vitamin D supplementation schedule.

Link between Viral Infections, Immune System, Inflammation and Diet

The strong spread of COVID-19 and the significant number of deaths associated with it could be related to improper lifestyles, which lead to a low-grade inflammation (LGI) that not only increases the risk of chronic diseases, but also the risk of facing complications relating to infections and a greater susceptibility to infections themselves. Recently, scientific research has widely demonstrated that the microbiota plays a fundamental role in modulating metabolic responses in the immune system. There is, in fact, a two-way interaction between lifestyle, infection, and immunity. The immune response is compromised if nutrition is unbalanced or insufficient, because diet affects the intestinal flora predisposing people to infections and, at the same time, the nutritional state can be aggravated by the immune response itself to the infection. We evaluate the link between balanced diet, the efficiency of the immune system, and microbiota with the aim of providing some practical advice for individuals, with special attention to the elderly. A correct lifestyle that follows the Mediterranean model, which is especially rich in plant-based foods along with the use of extra-virgin olive oil, are the basis of preventing LGI and other chronic pathologies, directly influencing the intestinal microbiota and consequently the immune response.

Mediterranean Diet In Healthy Aging

The World elderly population is expected to double before 2050. Unhealthy habits and unhealthy lifestyles are commonly associated with age-related diseases or their worsening. Modification in daily lifestyle and diet may help preventing age-related diseases onset and efficiently affecting their evolution, thus promoting the Healthy Aging process, concept recently coined to describe the disease-free aging process. This review highlights the role of nutrition science in promoting healthy aging. Since the Mediterranean Model demonstrated to be a useful style in supporting healthy aging, promotion of this correct lifestyle by health policies seems to be the best approach to achieve this target.

Racial and Ethnic Disparities in COVID-19 Outcomes: Social Determination of Health

As of 18 October 2020, over 39.5 million cases of coronavirus disease 2019 (COVID-19) and 1.1 million associated deaths have been reported worldwide. It is crucial to understand the effect of social determination of health on novel COVID-19 outcomes in order to establish health justice. There is an imperative need, for policy makers at all levels, to consider socioeconomic and racial and ethnic disparities in pandemic planning. Cross-sectional analysis from COVID Boston University's Center for Antiracist Research COVID Racial Data Tracker was performed to evaluate the racial and ethnic distribution of COVID-19 outcomes relative to representation in the United States. Representation quotients (RQs) were calculated to assess for disparity using state-level data from the American Community Survey (ACS). We found that on a national level, Hispanic/Latinx, American Indian/Alaskan Native, Native Hawaiian/Pacific Islanders, and Black people had RQs > 1, indicating that these groups are over-represented in COVID-19 incidence. Dramatic racial and ethnic variances in state-level incidence and mortality RQs were also observed. This study investigates pandemic disparities and examines some factors which inform the social determination of health. These findings are key for developing effective public policy and allocating resources to effectively decrease health disparities. Protective standards, stay-at-home orders, and essential worker guidelines must be tailored to address the social determination of health in order to mitigate health injustices, as identified by COVID-19 incidence and mortality RQs.

Validity and Usability of a Smartphone Image-Based Dietary Assessment App Compared to 3-Day Food Diaries in Assessing Dietary Intake Among Canadian Adults: Randomized Controlled Trial

Background

Accurate dietary assessment is needed in studies that include analysis of nutritional intake. Image-based dietary assessment apps have gained in popularity for assessing diet, which may ease researcher and participant burden compared to traditional pen-to-paper methods. However, few studies report the validity of these apps for use in research. Keenoa is a smartphone image-based dietary assessment app that recognizes and identifies food items using artificial intelligence and permits real-time editing of food journals.

Objective

This study aimed to assess the relative validity of an image-based dietary assessment app — Keenoa — against a 3-day food diary (3DFD) and to test its usability in a sample of healthy Canadian adults.

Methods

We recruited 102 participants to complete two 3-day food records. For 2 weeks, on 2 non-consecutive days and 1 weekend day, in random order, participants completed a traditional pen-to-paper 3DFD and the Keenoa app. At the end of the study, participants completed the System Usability Scale. The nutrient analyses of the 3DFD and Keenoa data before (Keenoa-participant) and after they were reviewed by dietitians (Keenoa-dietitian) were analyzed using analysis of variance. Multiple tests, including the Pearson coefficient, cross-classification, kappa score, % difference, paired t test, and Bland-Altman test, were performed to analyze the validity of Keenoa (Keenoa-dietitian).

Results

The study was completed by 72 subjects. Most variables were significantly different between Keenoa-participant and Keenoa-dietitian (P<.05) except for energy, protein, carbohydrates, fiber, vitamin B1, vitamin B12, vitamin C, vitamin D, and potassium. Significant differences in total energy, protein, carbohydrates, % fat, saturated fatty acids, iron, and potassium were found between the 3DFD and Keenoa-dietitian data (P<.05). The Pearson correlation coefficients between the Keenoa-dietitian and 3DFD ranged from .04 to .51. Differences between the mean intakes assessed by the 3DFD and Keenoa-dietitian were within 10% except for vitamin D (misclassification rate=33.8%). The majority of nutrients were within an acceptable range of agreement in the Bland-Altman analysis; no agreements were seen for total energy, protein, carbohydrates, fat (%), saturated fatty acids, iron, potassium, and sodium (P<.05). According to the System Usability Scale, 34.2% of the participants preferred using Keenoa, while 9.6% preferred the 3DFD.

Conclusions

The Keenoa app provides acceptable relative validity for some nutrients compared to the 3DFD. However, the average intake of some nutrients, including energy, protein, carbohydrates, % fat, saturated fatty acids, and iron, differed from the average obtained using the 3DFD. These findings highlight the importance of verifying data entries of participants before proceeding with nutrient analysis. Overall, Keenoa showed better validity at the group level than the individual level, suggesting it can be used when focusing on the dietary intake of the general population. Further research is recommended with larger sample sizes and objective dietary assessment approaches.

Prevalence of Vitamin D Deficiency in a Large Newborn Cohort from Northern United States and Effect of Intrauterine Drug Exposure

Vitamin D is not only a vital element in bone health but is also a prohormone. Data regarding distribution of vitamin D status among preterm and term neonates in the United States are limited. There are no data on the effect of intrauterine drug exposure on vitamin D status. Our objective was to determine the distribution of vitamin D levels among preterm and term neonates and the effect of intrauterine illicit drug exposure. We did a retrospective chart review of neonates admitted from 2009 to 2016 to our neonatal intensive care unit with serum 25-hydroxycholecalciferol (25[OH]D) levels measured during the hospital stay. Of 1517 neonates, the median 25[OH]D level was 19 ng/mL with 31% deficient and 49% insufficient, even though 75% of mothers took prenatal vitamins. In pregnant women, 38% were vitamin-D-deficient and 44% were vitamin-D-insufficient. Four hundred seventy-one neonates had intrauterine drug exposure, with a median 25[OH]D level of 22.9 ng/mL versus 17.8 ng/mL in nonexposed neonates (p = 0.001). Despite maternal prenatal vitamin intake, neonates are at risk of vitamin D deficiency. Maternal illicit drug use was not related to lower 25[OH]D levels in neonates.

Vitamin D Exposure and Ovarian Cancer Risk and Prognosis

Given the poor prognosis of ovarian cancer and limited population-level strategies for early detection and long-term treatment success, knowledge of modifiable risk factors for prevention and improved prognosis is important. Vitamin D has received wide scientific interest in cancer research as having the potential to be one such factor. We carried out a systematic narrative review of the literature on vitamin D and ovarian cancer risk and survival. We included 17 case-control and cohort studies on ovarian cancer incidence. Five analyses were of sun exposure, among which three reported an inverse association. Of 11 analyses of dietary vitamin D, two reported an inverse association. Among five studies of 25(OH)D levels, an inverse association was reported in two. Across all studies the findings were inconsistent, but some recent studies have suggested that vitamin D exposure at earlier ages may be important. Only three studies examining vitamin D exposure in relation to survival among ovarian cancer survivors were identified and the findings were inconsistent. The evidence to date supports a null influence of vitamin D on both ovarian cancer risk and survival. Future research should ensure that exposure assessment captures vitamin D exposure from all sources and for the etiologically or prognostically pertinent period.

Vitamin D ratio and glycaemic control in individuals with type 2 diabetes mellitus: A systematic review

Several studies have suggested a favorable role for vitamin D in glycaemic metabolism and its potential as adjuvant treatment of type 2 diabetes mellitus. This review discusses the role of vitamin D in the glycaemic control of individuals with type 2 diabetes mellitus and evaluates the effect of vitamin D supplementation on glycaemic markers in this population. Literature searches were performed in the BIREME, LILACS, and PubMed databases using the Medical Subject Headings and words related to vitamin D, type 2 diabetes mellitus, and glycaemic control. Interventional and observational studies were considered eligible. The evaluation of the included studies was independently performed by 2 evaluators at all stages of selection, data extraction, and bias risk assessment. The primary outcome was the relationship between vitamin D levels and glucose metabolism markers in type 2 diabetes mellitus individuals. The secondary outcome was the effect of vitamin D supplementation on the glycaemic control markers in individuals with type 2 diabetes mellitus. The inverse relationship between vitamin D and variables of glucose metabolism was verified. Interventional studies revealed that vitamin D supplementation did not alter glycaemic control markers in most studies. Few studies have shown positive effects with a significant reduction in the percentage of glycated haemoglobin, insulin, and glucose concentrations, and changes in homeostatic model assessment-insulin resistance and beta cell, and quantitative insulin sensitivity check index. Therefore, despite the association of vitamin D with glucose metabolism, there is insufficient evidence of the beneficial effects of its supplementation on the metabolic control of type 2 diabetes mellitus.

Vitamin D Levels Do Not Predict Risk of Metatarsal Fractures

INTRODUCTION

In the literature, there is conflicting data regarding the relationship between vitamin D and fractures. Reports on the effects of vitamin D levels on pathologies of the foot and ankle are limited. The purpose of this study is to assess the prevalence of vitamin D insufficiency in patients who have sustained low-energy metatarsal fractures compared to foot or ankle sprains without osseous involvement.

METHODS

Between May 2012 and August 2014, vitamin D levels and demographic data were collected prospectively in a total of 99 patients; 71 with metatarsal fractures and 28 with sprains, both from a low-energy mechanism of injury. Data between the metatarsal fracture group and sprain group were compared through univariate and multivariate analyses.

RESULTS

Mean vitamin D in the fracture group was 26.9 ng/mL (range = 78.0-4.3), and in the sprain group it was 27.1 ng/mL (range = 64.1-8.3; P = .93). Vitamin D insufficiency (<30 ng/mL) was present in 47 (66%) of fracture patients and 20 (71%) of sprain patients ( P = .81).

CONCLUSION

A high incidence of hypovitaminosis D was seen in all foot and ankle patients. There was no difference in mean vitamin D level or incidence of vitamin D insufficiency between patients with metatarsal fractures or sprains resulting from similar low-energy mechanisms.

LEVELS OF EVIDENCE

Level III: Prospective, case-control study.

Atraumatic Bilateral Fracture of the Femoral Neck in Young Male Patient with Suspected Osteomalacia

In this report, we describe the case of a healthy 37-year-old male patient without a history of disease, who developed atraumatic bilateral fracture of the femoral neck. Radiological and blood investigations revealed osteopenia and severe vitamin D deficiency (7.42 ng/mL), respectively, but patient had no apparent risk factors for insufficiency fracture. Bilateral osteosynthesis was obtained using cannulated screws and laboratory findings improved after vitamin D supplementation. This case highlights the effect of vitamin D deficiency on demineralization in a young male patient.

Dietary Supplements Commonly Used by Cancer Survivors: Are There Any Benefits?

Following a cancer diagnosis, dietary supplements are reportedly used by 20%-80% of individuals. Supplements are most commonly used by breast cancer survivors, followed by patients with prostate, colorectal, and lung cancers, which is not surprising since these are the most common types of cancer diagnosed in adults. Reasons cited for such use include improving quality of life, reducing symptoms related to treatment and/or the disease process, and recommendation from medical practitioners; family and friends may also be an influence. However, controversy surrounds the use of dietary supplements, particularly during treatment-specifically, whether supplements affect treatment efficacy is unknown. This article discusses the evidence related to common dietary supplements used to prevent cancer or a recurrence.

Prevalence of vitamin D insufficiency in children with forearm fractures

PURPOSE

This study aimed to determine whether children with distal radius impaction fractures have increased prevalence of 25-hydroxyvitamin D (25(OH) D) insufficiency compared with healthy controls.

PATIENTS AND METHODS

This is a prospective controlled study. The 30 children who were diagnosed with forearm fracture at the orthopaedic emergency clinic were included in the study and 30 healthy children from the routine paediatric outpatient unit were included as the control group. Peripheric venous 25(OH) D, calcium (Ca), magnesium (Mg), phosphor (P), alkaline phosphatase (ALP) and parathyroid hormone (PTH) of both groups were recorded. The sample size was estimated based on the effect size for a type I error of 5% and power of 80%.

RESULTS

Demographic characteristics of the two groups did not differ in terms of weekly physical activity levels and breast milk intake. The mean whole body BMI was similar in both groups of patients. History of previous fracture and 25(OH) D level were significantly lower in the patient group than the control group.

CONCLUSION

In the present study, the prevalence of vitamin D insufficiency or deficiency was higher in patients with forearm impaction type fractures than healthy controls and the baseline levels reported in the literature. In addition, there were no significant differences in serum Ca, Mg, P, ALP and PTH levels between the healthy controls and the patient group.

Vitamin D deficiency and sufficiency among Canadian children residing at high latitude following the revision of the RDA of vitamin D intake in 2010

Recently, countries at high latitudes have updated their vitamin D recommendations to ensure adequate intake for the musculoskeletal health of their respective populations. In 2010, the dietary guidelines for vitamin D for Canadians and Americans aged 1–70 years increased from 5 μg/d to 15 μg/d, whereas in 2016 for citizens of the UK aged ≥4 years 10 μg/d is recommended. The vitamin D status of Canadian children following the revised dietary guidelines is unknown. Therefore, this study aimed to assess the prevalence and determinants of vitamin D deficiency and sufficiency among Canadian children. For this study, we assumed serum 25-hydroxy vitamin D (25(OH)D) concentrations <30 nmol/l as ‘deficient’ and ≥50 nmol/l as ‘sufficient’. Data from children aged 3–18 years (n 2270) who participated in the 2012/2013 Canadian Health Measures Survey were analysed. Of all children, 5·6% were vitamin D deficient and 71% were vitamin D sufficient. Children who consumed vitamin D-fortified milk daily (77 %) were more likely to be sufficient than those who consumed it less frequently (OR 2·4; 95% CI 1·7, 3·3). The 9% of children who reported taking vitamin D-containing supplements in the previous month had higher 25(OH)D concentrations (β 5·9 nmol/l; 95% CI 1·3, 12·1 nmol/l) relative to those who did not. Children who were older, obese, of non-white ethnicity and from low-income households were less likely to be vitamin D sufficient. To improve vitamin D status, consumption of vitamin D-rich foods should be promoted, and fortification of more food items or formal recommendations for vitamin D supplementation should be considered.

Both high and low plasma levels of 25-hydroxy vitamin D increase blood pressure in a normal rat model

The lower threshold plasma 25-hydroxy vitamin D (25(OH)D) level for optimal cardiovascular health is unclear, whereas the toxicity threshold is less clear. The aim of this study was to examine the cardiovascular-vitamin D dose-response curve in a normal rat model. Doses of cholecalciferol ranged from deficiency to toxic levels (equivalent to human doses of 0, 0·015, 0·25 and 3·75mg/d) for 4 weeks, and then cardiovascular health was examined using blood pressure telemetry and high-resolution ultrasound in normal male rats (n 16/group, 64 rats total). After 1 month, only the 0·25mg/d group had plasma 25(OH)D that was within current recommended range (100-125 nmol/l), and all groups failed to change plasma Ca or phosphate. Systolic blood pressure increased significantly (10-15 mmHg) in the rat groups with plasma 25(OH)D levels at both 30 and 561 nmol/l (groups fed 0 and 3·75mg/d) compared with the group fed the equivalent to 0·015mg/d (43 nmol/l 25(OH)D). Although not significant, the group fed the equivalent to 0·25mg/d (108 nmol/l 25(OH)D) also showed a 10 mmHg increase in systolic blood pressure. Carotid artery diameter was significantly smaller and wall thickness was larger, leading to higher peak carotid systolic blood velocity in these two groups. Despite these vascular changes, cardiac function did not differ among treatment groups. The key finding in this study is that arterial stiffness and systolic blood pressure both showed a U-shaped dose-response for vitamin D, with lowest values (best cardiovascular health) observed when plasma 25(OH)D levels were 43 nmol/l in normal male rats.

The Effects of Vitamin D Deficiency and Insufficiency on the Endocrine and Paracrine Systems

Individuals are capable of producing vitamin D with proper exposure to sunlight. However, several factors can interfere with the effectiveness of this process. Most sunscreens filter out UVB light, thus inhibiting vitamin D production. Individuals with more darkly pigmented skin have greater difficulty producing vitamin D because melanin acts as an effective natural sunscreen, requiring longer sun exposure to produce an adequate daily allotment of vitamin D. Additionally, solely breastfed infants whose mothers suffered from vitamin D deficiency or insufficiency when pregnant have smaller reserves of the nutrient and are at greater risk of developing nutritional rickets. Vitamin D deficiency leads to rickets, osteomalacia, and osteoporosis. Long-term vitamin D insufficiency can lead to paracrine effects such as type 1 diabetes, cancer, and multiple sclerosis. This article reviews the current literature on vitamin D deficiency and insufficiency and their relation to different disease states. Potential areas for research are discussed.

Vitamin D Status in an Elective Orthopedic Surgical Population

BACKGROUND

Adequate vitamin D availability is required for normal bone metabolism. Hypovitaminosis D is highly prevalent in latitudes above 30 degrees. The goal of this prospective study was to determine the prevalence of hypovitaminosis D in an unselected population of patients undergoing major ankle or hindfoot arthrodesis in Burlington, Vermont (latitude 44.5° N).

METHODS

One hundred eighteen patients undergoing a major ankle, hindfoot, or midfoot arthrodesis between May 2012 and February 2014 were eligible for the study, of which 81 participated. All clinical data, including comorbidities, demographics, and lab values, were obtained from the comprehensive electronic medical record system that encompassed all inpatient and outpatient care. Based on the recommendations published by the Vitamin D Task Force Committee of the Endocrine Society, vitamin D levels above 30 ng/mL were considered normal. Statistical analyses were performed using a significance level of P <.05.

RESULTS

Of 81 patients tested, 54 (67%) had low serum vitamin D. Older patients had lower risk for hypovitaminosis D (RR = 0.953, CI = 0.908, 0.999, P = .046), whereas a Charlson Index ≥3 had increased risk (RR = 16.8, CI = 1.5, 192.3, P = .023). Of the 16 patients retested after vitamin supplementation, only 9 (56%) corrected to normal.

CONCLUSIONS

In an unselected population in Vermont undergoing hindfoot and ankle arthrodesis, there was a high prevalence of hypovitaminosis D, even in patients without predisposing risk factors. Consequently, routine testing or presumptive high-dose vitamin D replenishment therapy should be considered for all patients scheduled for such surgery, primarily to promote adequate skeletal calcium metabolism.

LEVEL OF EVIDENCE

Level II, prospective study.

Vitamin D and Colorectal, Breast, and Prostate Cancers: A Review of the Epidemiological Evidence

Over the past two decades, the question of whether vitamin D has a role in cancer incidence, progression, and mortality has been studied in detail. Colorectal, breast, and prostate cancers have been a particular area of focus; together, these three malignancies account for approximately 35% of cancer cases and 20% of cancer deaths in the United States, and as such are a major public health concern. Herein, we review and synthesize the epidemiological research regarding vitamin D, as measured by the biomarker 25-hydroxycholecalciferol [25(OH)D], and the incidence, progression, and mortality of these cancers. Overall, the results of observational studies of the relationship between 25(OH)D and colorectal cancer have revealed a consistent inverse association for incidence and mortality; while for breast cancer, results have generally demonstrated a relationship between higher 25(OH)D and lower risk for progression and mortality. In contrast, randomized, double-blind clinical trials conducted to date have generally failed to support these findings. For prostate cancer, there is no convincing evidence of an association between 25(OH)D and incidence, and inconsistent data for progression and mortality, though results of one open label clinical trial suggest that supplementation with 4000 IU/d of vitamin D3 may inhibit progression of the disease. Nonetheless, until the results of additional ongoing randomized, double-blind clinical trials are reported, it will be difficult to ascertain if vitamin D itself is related to a reduction in risk for some cancer endpoints, or whether high concentrations of the vitamin D biomarker 25(OH)D may instead serve as a marker for an overall beneficial risk factor profile.

Plasma vitamin D metabolites and C-reactive protein in stage-stop racing endurance sled dogs

Background

Dogs are a unique model for examining the effects of exercise on vitamin D status because of their lack of vitamin D synthesis by UV exposure. In addition, the inflammatory response may be associated with hypovitaminosis D.

Objectives

To investigate the effects of several days of endurance exercise on plasma vitamin D (25‐(OH)D₃, 24,25‐(OH)D₃ and 1,25(OH)D₃) and serum C‐reactive protein (CRP) concentrations in stage‐stop racing sled dogs.

Animals

12 racing sled dogs and 8 control dogs.

Methods

Blood was collected before the race and immediately after racing on days 2 and 8. Plasma vitamin D metabolites and serum CRP concentrations were measured.

Results

Racing dogs showed a significant increase in 25(OH)D₃ on day 2 (P = .027) and day 8 of the race (P < .001), whereas no increases were observed in control dogs. The plasma concentration of 24,25(OH)D₃ showed a significant increase by day 8 (P < .001). There were no significant changes in 1,25(OH) D₃ concentrations across all time points and groups. Racing dogs had significantly increased CRP concentrations by day 2 (39.3 ± 30.1 μg/mL; P < .001).

Conclusions and Clinical Importance

Increases in vitamin D metabolites as well as increases in CRP concentrations were observed in racing sled dogs. This finding was contrary to the hypothesis that decreases in vitamin D status in athletes may be related to the acute phase inflammatory response during exercise. In addition, the increased 24,25(OH)D₃ concentrations compared to what is observed in other species suggests metabolic variations in dogs that lead to enhanced disposal of vitamin D.

Association Between Inflammatory Bowel Disease and Vitamin D Deficiency: A Systematic Review and Meta-analysis

BACKGROUND

Vitamin D plays a role in several immune-mediated diseases, but its association with inflammatory bowel disease (IBD) is unclear. We conducted a systematic review and meta-analysis to assess the association between IBD and vitamin D deficiency.

METHODS

We searched electronic databases from inception to December 2014 for observational studies reporting the presence of vitamin D deficiency (defined as serum 25-hydroxycholecalciferol [25(OH)D] level of ≤20 ng/mL) in IBD patients and having a control group without IBD. Odds ratios (ORs) were combined using a random-effects model. Meta-regression was performed using latitude as a moderator. Study quality was assessed using the Newcastle-Ottawa scale.

RESULTS

Out of 816 citations, 14 eligible studies were identified, comprising 1891 participants (938 IBD cases and 953 controls). Meta-analysis showed that patients with IBD had 64% higher odds of vitamin D deficiency when compared with controls (OR = 1.64; 95% confidence interval, 1.30-2.08; I = 7%; P < 0.0001). Patients with ulcerative colitis had more than double the odds of vitamin D deficiency when compared with normal controls (OR = 2.28; 95% confidence interval, 1.18-4.41; I = 41%; P = 0.01). Latitude did not influence the association between IBD and vitamin D deficiency (P = 0.34). Generalizability of our results might be limited as we summarized unadjusted ORs, because of nonavailability of adjusted ORs in individual studies.

CONCLUSIONS

IBD is significantly associated with having higher odds of vitamin D deficiency. Well-designed randomized controlled trials and longitudinal studies are needed to further explain the role of vitamin D in IBD pathogenesis and its therapy.

Standardizing 25-hydroxyvitamin D values from the Canadian Health Measures Survey

BACKGROUND

The Canadian Health Measures Survey (CHMS) is an ongoing cross-sectional national survey that includes a measure of 25-hydroxyvitamin D [25(OH)D] by immunoassay. For cycles 1 and 2, the collection period occurred approximately every 2 y, with a new sample of ∼5600 individuals.

OBJECTIVE

The goal was to standardize the original 25(OH)D CHMS values in cycles 1 and 2 to the internationally recognized reference measurement procedures (RMPs) developed by the US National Institute for Standards and Technology (NIST) and Ghent University, Belgium.

DESIGN

Standardization was accomplished by using a 2-step procedure. First, serum samples corresponding to the original plasma samples were remeasured by using the currently available immunoassay method. Second, 50 serum samples with known 25(OH)D values assigned by the NIST and Ghent reference method laboratories were measured by using the currently available immunoassay method. The mathematical models for each step-i.e., 1) YCurrent = XOriginal and 2) YNIST-Ghent = XCurrent -were estimated by using Deming regression, and the 2 models were solved to obtain a single equation for converting the "original" values to NIST-Ghent RMP values.

RESULTS

After standardization (cycles 1 and 2 combined), the percentage of Canadians with 25(OH)D values <40 nmol/L increased from 16.4% (original) to 19.4% (standardized), and values <50 nmol/L increased from 29.0% (original) to 36.8% (standardized). The 25(OH)D standardized distributions (cycles 1 and 2 analyzed separately) were similar across age and sex groups; slightly higher values were associated with cycle 2 in the young and old. This finding contrasts with the original data, which indicated that cycle 2 values were lower for all age groups.

CONCLUSION

The shifts in 25(OH)D distribution brought about by standardization indicate its importance in drawing correct conclusions about potential population deficiencies and insufficiencies and in permitting the comparison of distributions between national surveys.

Low Vitamin D Levels in Children with Fractures: a Comparative Cohort Study

BACKGROUND

The currently accepted ranges for "normal" serum vitamin D have recently been challenged in adults on the basis that healthy bone metabolism requires higher levels of vitamin D than previously thought.

PURPOSE

The purpose of this study was to evaluate whether a new "biologically based" classification based on 25(OH)vitamin D levels that invoke an endocrine biomarker response (<20 ng/mL for deficiency and <32 ng/mL for insufficiency) is more appropriate for children with fractures than historical criteria.

METHODS

Serum 25(OH)vitamin D levels were collected from 58 children with acute low-energy fractures from an outpatient orthopedic clinic from 2009 to 2012. These vitamin D levels were compared with a cohort of 103 children with chronic kidney disease (CKD) from an adjacent clinic, a condition with acknowledged low levels of vitamin D. Then, the prevalence of vitamin D sufficiency in the fracture cohort was evaluated and compared using both historical guidelines and newer biologically based criteria.

RESULTS

25(OH)vitamin D levels in the fracture cohort did not differ from levels in the CKD cohort (27.5 vs. 24.6 ng/mL) indicating a similar distribution of vitamin D levels. This finding was consistent when controlling for significant covariables using linear regression analyses. In the fracture cohort, there was a discrepancy between historical and biologically based criteria in 64% of children.

CONCLUSIONS

The results of the current study suggest that fracture patients are more frequently vitamin D deficient than previously thought. This finding is more readily apparent when newer biologically based criteria for vitamin D sufficiency are used.

The Relationship Between Serum 25-Hydroxyvitamin D Levels and Nuclear Cataract in the Carotenoid Age-Related Eye Study (CAREDS), an Ancillary Study of the Women's Health Initiative

PURPOSE

To investigate the relationship between serum 25-hydroxyvitamin D (25[OH]D) levels and nuclear cataract among participants of the Carotenoids in Age-Related Eye Disease Study (CAREDS), an ancillary study of the Women's Health Initiative (WHI) Observational Study (OS).

METHODS

Nuclear cataract was assessed from slit lamp photographs (2001-2004) taken 6 years after collecting serum analyzed for 25(OH)D levels at WHI baseline (1994-1998) in 1278 CAREDS participants age 50 to 79 years. Multivariate (age, iris color, smoking, pulse pressure) odds ratios (ORs) for nuclear cataract (nuclear opacities > level 4 or cataract extraction) by quintiles of serum 25(OH)D were estimated using logistic regression.

RESULTS

No significant association was observed between serum 25(OH)D and nuclear cataract among women of all ages (age-adjusted OR [95% confidence interval (CI)] 0.97 [0.65-1.45]). However, there was a significant age interaction (P for interaction = 0.04). There were no significant associations in the women 70 years or older. In women younger than 70 years, we observed an inverse association between serum 25(OH)D and nuclear cataract (multivariate adjusted ORs [95% CI] 0.54 [0.29-0.99] and 0.66 [0.36-1.20] for quintiles 4 and 5 vs. 1, respectively; P = 0.03). Further adjustment for 25(OH)D determinants (body mass index, vitamin D intake, and UVB exposure) attenuated this association.

CONCLUSIONS

Serum 25(OH)D levels were unrelated to nuclear opacities in this study sample. However, exploratory analyses suggest a protective association in women younger than 70 years. Further investigations of the relationship between vitamin D and nuclear lens opacities are warranted.

Association of antepartum vitamin D levels with postpartum pelvic floor muscle strength and symptoms

INTRODUCTION AND HYPOTHESIS

Vitamin D affects skeletal muscle strength and functions via various mechanisms. Strength and/or functional dysfunctions of the pelvic floor muscles may be associated with the distortion of pelvic floor functions. We hypothesized that vitamin D deficiency may contribute to pelvic floor dysfunction (PFD) by affecting pelvic floor muscle strength (PFMS). The aim of this study was to assess the effect of vitamin D deficiency during pregnancy on postpartum PFMS.

METHODS

This cross-sectional study was conducted in a university hospital. One hundred and eighty pregnant women were admitted to our hospital in their third trimester and compared with 156 healthy nulliparous women. Venous blood samples for examining vitamin D levels were taken from each participant and stored at -80 °C. At 8-10 weeks postpartum, patients were invited to the hospital, asked about their PFD symptoms, and PFMS was measured using a perineometer.

RESULTS

There was no statistical significance among groups regarding mean age, maternal age, and weight at delivery. Postpartum PFMS and duration in vitamin D-deficient women were significantly lower than those without the deficiency. Vitamin D-deficient vaginal delivery cases (group I) had a postpartum PFMS average of 21.96 ± 7.91 cm-H₂O, nonvitamin D-deficient normal delivery cases (group III) had a PFMS of 29.66 ± 10.3 cm-H₂O (p = 0.001). In the cesarean delivery groups, vitamin D-deficient (group II) and nonvitamin D-deficient (group IV) cases had PFMS values of 32.23 ± 9.66 and 35.53 ± 15.58 cm-H₂O respectively (p = 0.258).

CONCLUSIONS

Lower vitamin D levels in the third trimester correlates with decreased PFMS.

Suspected coexistent osteoporosis and osteomalacia with atraumatic bilateral neck of femur fractures in a 53-year-old man without apparent risk factors

Atraumatic bilateral hip fractures in the relatively young are exceedingly rare. In this case report, we present one such patient diagnosed by MRI and treated with bilateral hip screws. Subsequent investigations revealed severe osteoporosis and primary 25-hyroxyvitamin D (25OHD) deficiency at a level suggestive of concurrent osteomalacia.

A multilevel model of postmenopausal breast cancer incidence

BACKGROUND

Breast cancer has a complex etiology that includes genetic, biologic, behavioral, environmental, and social factors. Etiologic factors are frequently studied in isolation with adjustment for confounding, mediating, and moderating effects of other factors. A complex systems model approach may present a more comprehensive picture of the multifactorial etiology of breast cancer.

METHODS

We took a transdisciplinary approach with experts from relevant fields to develop a conceptual model of the etiology of postmenopausal breast cancer. The model incorporated evidence of both the strength of association and the quality of the evidence. We operationalized this conceptual model through a mathematical simulation model with a subset of variables, namely, age, race/ethnicity, age at menarche, age at first birth, age at menopause, obesity, alcohol consumption, income, tobacco use, use of hormone therapy (HT), and BRCA1/2 genotype.

RESULTS

In simulating incidence for California in 2000, the separate impact of individual variables was modest, but reduction in HT, increase in the age at menarche, and to a lesser extent reduction in excess BMI >30 kg/m(2) were more substantial.

CONCLUSIONS

Complex systems models can yield new insights on the etiologic factors involved in postmenopausal breast cancer. Modification of factors at a population level may only modestly affect risk estimates, while still having an important impact on the absolute number of women affected.

IMPACT

This novel effort highlighted the complexity of breast cancer etiology, revealed areas of challenge in the methodology of developing complex systems models, and suggested additional areas for further study.

A review of the anterior visual pathway model and the study of vitamin D in demyelinating disease

In recent years, theories about the anti-inflammatory properties of vitamin D in demyelinating disease have been well substantiated by human studies examining relapse reduction, MRI lesion activity and risk of MS conversion. However, the evidence that vitamin D may protect against neurodegeneration has not been established as of yet, and comes with the challenges of a manageable target over a manageable time period. Such challenges might be overcome by the anterior visual pathway (AVP) model of the central nervous system, which allows the non-invasive study (e.g. imaging, electrophysiology and clinical) of form and function within a much shorter time frame than pure clinical activity. This review outlines the state of current knowledge about vitamin D in demyelinating disease, and highlights the potential utility of using the AVP to study its neuroprotective effects.

Vitamin D: deficiency, sufficiency and toxicity

The plethora of vitamin D studies over the recent years highlight the pleomorphic effects of vitamin D outside its conventional role in calcium and bone homeostasis. Vitamin D deficiency, though common and known, still faces several challenges among the medical community in terms of proper diagnosis and correction. In this review, the different levels of vitamin D and its clinical implications are highlighted. Recommendations and consensuses for the appropriate dose and duration for each vitamin D status are also emphasized.

Atherosclerosis in systemic lupus erythematosus

Accelerated atherosclerosis and its long-term sequelae are a major cause of late mortality among patients with systemic lupus erythematosus (SLE). Traditional Framingham risk factors such as hypertension, hypercholesterolemia, diabetes, and smoking do not account in entirety for this risk. SLE specific factors like disease activity and duration, use of corticosteroids, presence of antiphospholipid antibodies, and others are important risk factors. SLE is considered a coronary heart disease; equivalent and aggressive management of all traditional risk factors is recommended. Despite their role in primary and secondary prevention in the general population, statins seem to have no effect on cardiovascular outcomes in adult or pediatric SLE populations. The use of hydroxychloroquine has a cardioprotective effect, and mycophenolate mofetil may reduce cardiovascular events based on basic science data and data from the transplant population. The role of vitamin D supplementation and treatment of hyperhomocysteinemia remain controversial, but due to the safety of therapy and the potential benefit, they remain as optional therapies.

Vitamin D status and cardiometabolic assessment in infancy

BACKGROUND

Infants are at risk of vitamin D insufficiency, owing to their limited exposure to direct sunlight and the low levels of vitamin D in breast milk. Although vitamin D insufficiency has been associated with cardiometabolic risk factors in children, these associations have not been studied in infants, despite their unique risks. Therefore, we sought to determine whether vitamin D status was associated with cardiometabolic measures in infants.

METHODS

Ninety-nine full-term infants were evaluated at the age of 1 y with measurement of 25-hydroxy vitamin D (25-OH-D) and an array of traditional (fasting glucose, insulin, low-density-lipoprotein cholesterol, high-density-lipoprotein cholesterol, triglycerides) and emerging (C-reactive protein, adiponectin, leptin) cardiometabolic risk factors. On the basis of 25-OH-D levels, infants were classified as vitamin D sufficient (n = 59), vitamin D insufficient (n = 29), or vitamin D deficient (n = 11).

RESULTS

Duration of exclusive breastfeeding and prevalence of nonwhite ethnicity were highest in the vitamin D-deficient group (P = 0.05 and 0.03, respectively). Current use of vitamin D supplementation was highest in the sufficient group (P = 0.02). Of note, however, there were no significant differences among the three groups in any of the cardiometabolic risk factors, on both unadjusted and covariate-adjusted analyses.

CONCLUSION

Vitamin D insufficiency/deficiency is not associated with an adverse cardiometabolic risk factor profile in 1-y-old infants.

Bone health: part 1, nutrition

Nutrition, in sufficient amount and substance, is crucial for healthy growth and development of the skeleton and surrounding tissues, especially in physically active populations. Inadequate nutrition has been linked to maladies such as the female athlete triad, as well as poor training or competitive performance and increased risk of injury. Dietary choices favoring items high in quality protein of animal or plant origin, polyunsaturated fatty acids, fruits and vegetables high in potassium and fiber, and dairy products or other beverages fortified with calcium and vitamin D are essential to athletes to ensure adequate vitamin and mineral availability to the skeleton, which in turn can affect peak physical performance.

Vitamin D deficiency and its association with low bone mineral density, HIV-related factors, hospitalization, and death in a predominantly black HIV-infected cohort

BACKGROUND

Low bone mineral density (BMD) is common among patients infected with human immunodeficiency virus (HIV) and present in higher rates in black subjects. This study assessed vitamin D levels in HIV cases versus noninfected matched controls to determine if deficiency was associated with BMD and HIV clinical outcomes.

METHODS

In total, 271 military beneficiaries with HIV underwent dual energy x-ray absorptiometry (DEXA) screening in 2001-2. Serum 25OH-vitamin D levels were determined using stored serum from the time of DEXA and 6-18 months prior. Two non-HIV-infected controls for each active duty case (n = 205) were matched on age, sex, race, zip code, and season using the Department of Defense Serum Repository (DoDSR). Vitamin D levels <20 ng/mL were considered deficient. HIV-related factors and clinical outcomes were assessed using data collected in the DoD HIV Natural History study.

RESULTS

In total, 165 of 205 (80.5%) active duty HIV cases had 2 matched controls available. HIV cases had greater odds of for vitamin D deficiency (VDD) compared with controls (demographics adjusted paired data odds ratio [OR], 1.46, 95% confidence interval [CI], .87-2.45), but this was not statistically significant. Blacks were disproportionately deficient (P <.001) but not relative to HIV status or BMD. Low BMD was associated with typical risk factors (low body mass index and exercise levels, alcohol use); given limited available data the relationship between tenofovir exposure and VDD or low BMD could not be determined. Analysis of HIV-specific factors and outcomes such as exposure to antiretrovirals, HIV progression, hospitalizations, and death revealed no significant associations with vitamin D levels.

CONCLUSIONS

VDD was highly prevalent in black HIV- infected persons but did not explain the observed racial disparity in BMD. Vitamin D deficiency was not more common among HIV- infected persons, nor did it seem associated with HIV- related factors/clinical outcomes.

Low dietary vitamin D predicts 34-year incident stroke: the Honolulu Heart Program

BACKGROUND AND PURPOSE

Vitamin D deficiency has been reported to contribute to the risk of cardiovascular disease, especially stroke. We examined the relationship between dietary vitamin D intake and 34-year incident stroke.

METHODS

The Honolulu Heart Program is a prospective population-based cohort study of 8006 Japanese-American men in Hawaii who were 45 to 68 years old at the baseline examination in 1965 to 1968. Dietary vitamin D intake was calculated using the Nutritionist IV Version 3 software from a 24-hour dietary recall. Subjects with prevalent stroke were excluded, leaving 7385 men followed through 1999 for incident stroke. Subjects were divided into quartiles of dietary vitamin D for analyses.

RESULTS

During 34 years of follow-up, 960 subjects developed stroke. Age-adjusted rates of incident stroke were significantly higher in the lowest dietary vitamin D quartile compared with the highest (all stroke: 6.38 versus 5.14 per 1000 person-years follow-up, P=0.030; thromboembolic stroke: 4.36 versus 3.30, P=0.033). Using Cox regression, adjusting for age, total kilocalories, body mass index, hypertension, diabetes mellitus, pack-years smoking, physical activity index, serum cholesterol, and alcohol intake, those in the lowest quartile had a significantly increased risk of incident stroke (all stroke hazard ratio, 1.22; 95% CI, 1.01-1.47; P=0.038; thromboembolic stroke hazard ratio, 1.27; 95% CI, 1.01-1.59; P=0.044) with the highest as the reference. We found no significant associations between dietary vitamin D and hemorrhagic stroke.

CONCLUSIONS

Low dietary vitamin D intake was an independent risk factor for 34-year incidence of all stroke and thromboembolic stroke in Japanese-American men. Additional research is needed on vitamin D supplementation to prevent stroke.

Vitamin D status among 4-month-old infants in New England: a prospective cohort study

BACKGROUND

Concerns over vitamin D deficiency in infants and children recently prompted the American Academy of Pediatrics to recommend increased supplementation. Few studies have examined vitamin D status in the same infants over time. Also, while many researchers label "breastfeeding" as a risk factor for vitamin D deficiency, few differentiate between any breastfeeding, exclusive breastfeeding, and supplemented or unsupplemented breastfeeders.

OBJECTIVE

To determine predictors of 25(OH)D deficiency at 4 months in a group of children previously tested at birth.

METHODS

We enrolled newborns from 2005 to 2007 at an urban Boston hospital. Maternal and infant blood samples were collected within 72 hours of birth. At 4 months, we obtained a second infant blood sample.

RESULTS

At 4 months, 11.9% of the 177 infants were vitamin D deficient compared to 37.5% at birth (25(OH)D <20 ng/mL). Median 25(OH)D was 35.2 ng/mL (range, 5-100.8; 95% confidence interval [CI], 32.8-37.6). At 4 months, 40% of unsupplemented infants were deficient. Lack of supplementation was significantly associated with increased risk of deficiency (adjusted odds ratio [AOR], 19.3; 95% CI, 4.80-77.2). Being outside at least 10 minutes a day, once per week, was protective (AOR, 0.12; 95% CI, 0.02-0.66), as was increasing gestational age (AOR, 0.36; 95% CI, 0.19-0.69). In 48.4% of patients, physicians failed to prescribe vitamin D at 2 months.

CONCLUSIONS

Despite inconsistent supplementation, a smaller proportion of infants were vitamin D deficient at 4 months than at birth. While supplemented breastfed infants were not at risk of deficiency, unsupplemented exclusively breastfed infants were at high risk of severe deficiency.

Vitamin D status and biomarkers of inflammation in runners

BACKGROUND AND PURPOSE

The extra-skeletal functions of vitamin D - including its role in inflammatory modulation - are now well recognized but have not yet been investigated in an athletic population. Thus, the purpose of this study was to investigate the relationship between vitamin D status and pro- and anti-inflammatory cytokines (as markers of inflammation and immune system function) in endurance athletes.

PATIENTS AND METHODS

We analyzed fasting blood samples from 19 healthy, endurance-trained male and female runners (following a standardized diet and exercise regimen) for vitamin D status (serum 25-hydroxyvitamin D [25(OH)D)] and specific plasma cytokine concentrations (tumor necrosis factor alpha [TNF-α], interferon-gamma [IFN-γ], interleukin [IL]-4, and IL-10). Serum/plasma concentrations were log-transformed and simple regression analysis was used to determine significant associations between 25(OH)D and cytokine concentrations.

RESULTS

Forty-two percent of participants had insufficient vitamin D status [25(OH)D< 32 ng/mL], whereas 11% were deficient [25(OH)D < 20 ng/mL]. TNF-α and IL-4 were variable, ranging from 2.9 to 36.4 pg/mL and 0 to 252.1 pg/mL, respectively. Concentrations of IFN-γ and IL-10 were minimal, with means of 6.7 ± 7.0 pg/mL and 4.8 ± 5.1 pg/mL, respectively. Regression analysis revealed a significant inverse association between 25(OH)D and TNF-α concentrations (R(2) = 56.5, P < 0.001) but not between 25(OH)D and the remaining cytokines, IFN-γ, IL-4, and IL-10 (P = 0.477, 0.694, and 0.673, respectively).

CONCLUSION

These results call further attention to the epidemic of vitamin D insufficiency, even in outdoor athletes, and support a possible link between decreased vitamin D status and one particular marker of inflammation. Future investigations are necessary to determine whether increased inflammation in athletes with reduced vitamin D status could increase risk for inflammation-related injury.

The association between breast cancer prognostic indicators and serum 25-OH vitamin D levels

BACKGROUND

Studies show that women with low vitamin D levels have an increased risk of breast cancer (BC) incidence and mortality, but there is a lack of research examining vitamin D levels and prognostic variables in BC patients. The aim of this study is to examine 25-OH vitamin D levels between BC cases and controls and by prognostic indicators among BC cases.

METHODS

25-OH vitamin D levels were collected from 194 women who underwent BC surgery and 194 cancer-free (CF) controls at the University of Rochester between January 2009 and October 2010. Mean 25-OH vitamin D levels and odds ratios (OR) were calculated by case/control status for the overall cohort and by prognostic indicators (invasiveness, ER status, triple-negative status, Oncotype DX score, molecular phenotype) for BC cases.

RESULTS

BC cases had significantly lower 25-OH vitamin D levels than CF controls (BC: 32.7 ng/mL vs. CF: 37.4 ng/mL; P = .02). In case-series analyses, women with suboptimal 25-OH vitamin D concentrations (<32 ng/mL) had significantly higher odds of having ER- (OR = 2.59, 95% confidence interval [95% CI] = 1.08-6.23) and triple-negative cancer (OR = 3.15, 95% CI = 1.05-9.49) than those with optimal 25-OH D concentrations. Women with basal-like phenotype had lower 25-OH vitamin D levels than women luminal A phenotype (basal-like: 24.2 ng/mL vs. luminal A: 32.8 ng/mL; P = 0.04).

CONCLUSIONS

BC patients with a more aggressive molecular phenotype (basal-like) and worse prognostic indicators (ER- and triple-negative) had lower mean 25-OH vitamin D levels. Further research is needed to elucidate the biological relationship between vitamin D and BC progression.

Vitamin D status: a review with implications for the pelvic floor

Vitamin D is a micronutrient vital in calcium homeostasis and musculoskeletal function. Vitamin D insufficiency is a common variant of vitamin D deficiency that shows clinical signs of rickets and osteomalacia. The clinical significance of vitamin D insufficiency is being explored in several medical conditions. However, the most robust work suggests a role in musculoskeletal disease. The pelvic floor is a unique part of the body and the function of which is dependent on interrelationships between muscle, nerve, connective tissue, and bone. Pelvic floor disorders result when these relationships are disrupted. This paper reviews current knowledge regarding vitamin D nutritional status, the importance of vitamin D in muscle function, and how insufficient or deficient vitamin D levels may play a role in the function of the female pelvic floor.

Vitamin D status in women with pelvic floor disorder symptoms

INTRODUCTION AND HYPOTHESIS

Our aim was to characterize the relationship between 25-hydroxyvitamin D [25(OH)D] status with pelvic floor symptom distress and impact on quality of life.

METHODS

A retrospective chart review was performed in women with a 25(OH)D level drawn within 1 year of their gynecology/urogynecology visit. Validated questionnaires including the Colorectal-Anal Distress Inventory (CRADI)-8 and Incontinence Impact Questionnaire (IIQ-7) were used. Multivariate analyses characterized pelvic floor disorder (PFD) symptom differences among women by vitamin D status.

RESULTS

We studied 394 women. Mean ± standard deviation (SD) 25(OH)D levels were higher in women without than with PFD symptoms (35.0 ± 14.1 and 29.3 ± 11.5 ng/ml, respectively (p < 0.001)]. The prevalence of vitamin D insufficiency was 51% (136/268). CRADI-8 and IIQ-7 scores were higher among women with vitamin D insufficiency (p = 0.03 and p = 0.001, respectively). Higher IIQ-7 scores were independently associated with vitamin D insufficiency (p < 0.001).

CONCLUSIONS

Insufficient vitamin D is associated with increased colorectal symptom distress and greater impact of urinary incontinence on quality of life.

Circulating vitamin D and colorectal adenoma in asymptomatic average-risk individuals who underwent first screening colonoscopy: a case-control study

BACKGROUND

A higher circulating vitamin D level is inversely associated with the risk of colorectal cancer, but the association with adenoma risk is less clear.

AIMS

We examined the association between the circulating 25-hydroxyvitamin D(3) [25(OH)D(3)] concentration and colorectal adenoma in asymptomatic average-risk participants undergoing initial screening colonoscopy.

METHODS

The study subjects were comprised of 143 cases of colorectal adenomas and 143 age- and gender-matched controls with normal colonoscopy among the 586 asymptomatic average-risk subjects (median age, 58 years; range, 50-73 years) who underwent first screening colonoscopy and measurement of the serum 25(OH)D(3) between December 2009 and April 2010, consistent with winter months of the region.

RESULTS

The mean concentration of serum 25(OH)D(3) in the adenoma and control groups was 20.0 ± 11.0 ng/ml and 25.0 ± 20.0 ng/ml, respectively (P = 0.009). Using multivariate analysis, higher levels of 25(OH)D(3) were associated with a statistically significant decreased risk of colorectal adenoma after multivariable adjustment (highest vs. lowest quartile OR 0.38, 95% CI 0.18-0.80, P (trend) = 0.012). The inverse association of circulating 25(OH)D(3) with colorectal adenoma was stronger among the patients with proximal adenoma than that among the patients without proximal adenoma (highest vs. lowest quartile OR 0.29, 95% CI 0.13-0.66, P (trend) = 0.001).

CONCLUSIONS

The present study suggests that high levels of circulating vitamin D are associated with a decreased risk of colorectal adenoma, and especially adenoma located in the proximal colon.

Healthy eating perceptions of older adults living in Canadian rural and northern communities

Aging produces physiologic changes that can affect the nutritional health of the older adult. It is estimated that 80% of community-dwelling older adults have inadequate intakes of four or more nutrients. Socioeconomic factors, such as income and geographic location, can also play an important role in nutritional status; however, limited research is available that specifically explores this. The purpose of this qualitative study was to examine the healthy eating perceptions of older adults residing in rural and northern communities in one Canadian province. Five focus groups were conducted in three rural and two northern Manitoba communities. Thirty-nine older adults participated in audio-recorded focus groups. Five themes emerged from the discussions. All respondents stated that healthy eating was important, but knowledge deficits were observed regarding label reading, understanding and visualizing portion sizes, and vitamin D recommendations and sources. Food programs were not commonly attended by participants due to availably and resistance. Regularly delivered nutrition education programs would assist in providing current nutrition information to older adults and their families in rural settings.