Vitamin D status among healthy postmenopausal women in South America

Calcifediol: a review of its pharmacological characteristics and clinical use in correcting vitamin D deficiency

BACKGROUND

In addition to the role of vitamin D in bone mineralization, calcium and phosphate homeostasis, and skeletal health, evidence suggests an association between vitamin D deficiency and a wide range of chronic conditions. This is of clinical concern given the substantial global prevalence of vitamin D deficiency. Vitamin D deficiency has traditionally been treated with vitamin D₃ (cholecalciferol) or vitamin D₂ (ergocalciferol). Calcifediol (25-hydroxyvitamin D₃) has recently become available more widely.

METHODS

By means of targeted literature searches of PubMed, this narrative review overviews the physiological functions and metabolic pathways of vitamin D, examines the differences between calcifediol and vitamin D₃, and highlights clinical trials conducted with calcifediol in patients with bone disease or other conditions.

RESULTS

For supplemental use in the healthy population, calcifediol can be used at doses of up to 10 µg per day for children ≥ 11 years and adults and up to 5 µg/day in children 3-10 years. For therapeutic use of calcifediol under medical supervision, the dose, frequency and duration of treatment is determined according to serum 25(OH)D concentrations, condition, type of patient and comorbidities. Calcifediol differs pharmacokinetically from vitamin D₃ in several ways. It is independent of hepatic 25-hydroxylation and thus is one step closer in the metabolic pathway to active vitamin D. At comparable doses to vitamin D₃, calcifediol achieves target serum 25(OH)D concentrations more rapidly and in contrast to vitamin D₃, it has a predictable and linear dose-response curve irrespective of baseline serum 25(OH)D concentrations. The intestinal absorption of calcifediol is relatively preserved in patients with fat malabsorption and it is more hydrophilic than vitamin D₃ and thus is less prone to sequestration in adipose tissue.

CONCLUSION

Calcifediol is suitable for use in all patients with vitamin D deficiency and may be preferable to vitamin D₃ for patients with obesity, liver disease, malabsorption and those who require a rapid increase in 25(OH)D concentrations.

Effectiveness of eight-week zinc supplementation on vitamin D3 status and leptin levels in a population of postmenopausal women: a double-blind randomized trial

BACKGROUND

The menopausal period is characterized by hormonal imbalance related to the alteration of parameters involved in lipid metabolism. In addition, menopause increases the risk of deficiencies of key vitamins and minerals such as vitamin D and zinc in such women. The present study investigates the influence of zinc supplementation on the status of vitamin D₃ and other lipid parameters in postmenopausal women.

METHODS

Fifty-one healthy postmenopausal women aged 44-76 years from the province of Granada (Spain) were divided into two groups (placebo and zinc) of 25 and 26 women, respectively. The zinc group was supplemented with 50 mg/day of zinc for 8 weeks. Nutrient intake assessment was performed by means of a 24 -h reminder. Zinc was determined by flame atomic absorption spectrophotometry. Vitamin D was analyzed by liquid chromatography - tandem mass spectrometry. Leptin was determined by enzyme immunoassay.

RESULTS

Zinc supplementation improved the initial vitamin D₃ status of the postmenopausal population (p = 0.049). Plasma levels of 25-OH-D₃ increased significantly after Zn supplementation in women with lower age at menopause (p = 0.045). Both intake and plasma zinc levels were inversely correlated to serum leptin levels (p = 0.044 and p = 0.033, respectively), being significantly lower in lower age at menopause (p < 0.001).

CONCLUSION

Zinc supplementation improved vitamin D₃ status and was associated to low leptin levels in the postmenopausal women of the study.

[How does vitamin D influence body composition, sarcopenia and lifespan in older persons? A retrospective study of nine years]

Introduction

Background: hypovitaminosis D has a prevalence of 50,4% in older persons. This population has grown globally in an impressive way during the last 20 years. In addition, the deficiency of vitamin D (< 30 ng/ml) could raise the risk of mortality in this population. Objectives: to know whether vitamin D levels less than 30 ng/ml have an impact on mortality for overall causes, cardiovascular causes, cancer or injuries (falls) in a follow-up period of nine years in elderly subjects. Methods: a retrospective longitudinal study with nine years period of observation; 418 elderly subjects were followed, and they were recruited in 2004 to participate in a study about vitamin D supplementation and muscle strength. Results: vitamin D levels below 30 ng/dl increase by almost three times the probability of dying (OR = 2.77, IC = 1.81-3.85), while the same level of vitamin D is associated with a double risk of dying from cardiovascular causes (OR = 1.78, CI = 1.21-2.09) in the unadjusted model. For cancer mortality and falls, no significant results were obtained. Vitamin D would not act as a protective factor against mortality. Conclusions: vitamin D levels less than 30 ng/ml could be a risk factor for general mortality.

Vitamin D Levels of Outpatients Admitted to a University Hospital in the Marmara Region of Turkey Over 3 Years

BACKGROUND

Vitamin D regulates calcium and phosphorus metabolism, and it is essential for bone formation. Several factors can affect vitamin D levels in plasma. In present study we compare vitamin D levels of outpatients, who admit to Maltepe University Hospital between 2011 and 2013 and had vitamin D measurements regarding gender, age, and season.

METHODS

Hospital records were evaluated to identify the outpatients with vitamin D levels and their gender, age, and vitamin D levels and the seasons of measurements were recorded.

RESULTS

Data of 4860 subjects (74% female) were analyzed and 69.2% were between 18-64 years old. Vitamin D levels were as follows: 43.1% ≤ 10 ng/mL, 31.9% between 10 ng/mL and 20 ng/mL, 16.1% between 20 ng/mL and 30 ng/mL, and only 8.9% ≥ 30 ng/mL. The number of females with vitamin D levels < 10 ng/mL was significantly higher than that of males, while the number of males with vitamin D levels between 10 ng/mL and 20 ng/mL was significantly higher than that of females (P = 0.001) for each of the individuals, 6.2% and 11.1% had sufficient levels in winter and summer, respectively. Overall, it was observed that 6.6% of individuals between 18-44 years old, 8.2% of individuals between 45-64 years old and 10.3% of individuals over 65 years old had vitamin D levels > 30 ng/mL.

CONCLUSIONS

The prevalence of vitamin D deficiency in outpatients of Maltepe University Hospital in Marmara region was 75% (< 20 ng/mL).

25-Hydroxyvitamin D serum levels in rheumatic female patients in southeast Spain: The paradigm of daily optimal sunshine levels and inadequate vitamin D status

BACKGROUND

Almeria is a region in southeast Spain with optimal sunlight levels, along with low pluvial and pollution rates. If exposure to sunlight is sufficient to maintain adequate levels of vitamin D (25OHD), this population should display high serum levels.

OBJECTIVES

To describe 25OHD serum status in women from Almeria and evaluate the impact of long sunlight exposure along the seasons on 25OHD.

METHODS

Cross-sectional study, performed in women consecutively recruited from an outpatient rheumatology clinic. Serum levels of 25OHD were assessed in all patients and evaluated according to age (<48 yrs, 48-53 yrs, 54-60 yrs and >60 yrs), season, and presence or absence of menopause. Clinical and laboratory variables that could affect status of vitamin D were also considered.

RESULTS

The sample included 319 Caucasian female patients. Mean 25OHD were 30.2ng/ml with 195 (61.1%) exhibiting 25OHD inadequate serum levels. Season had a significant effect on 25OHD levels, with autumn being the season in which 25OHD serum levels remained well above 30ng/ml in all age bands, and winter the season with more levels of insufficiency. Menopause did not modify 25OH serum levels. Women whose age was below 48 and over 60 had inadequate levels of 25OHD during summer.

CONCLUSIONS

Optimal levels of sunlight could not overcome the problem of inadequate 25OHD serum levels, particularly in elderly and young female population. Vitamin D supplementation may be recommended predominantly in winter and summer in this population.

Hypovitaminosis D and Its Associated Factors in North Algerian Postmenopausal Women: Results of a Cross-Sectional Study

PURPOSE

As the vitamin D status of Algerian postmenopausal women was poorly described, this cross-sectional study investigated the prevalence of low vitamin D status in a sample population. Secondarily, predictive factors of this hypovitaminosis D were explored.

METHODS

All the 336 selected women ≥ 45 years from Douera were interviewed to get anthropometric and lifestyle data, reproductive and medical history, medications, and calcium/vitamin D intakes. A blood sample was collected to measure 25-hydroxyvitamin D (25(OH)D) concentrations.

RESULTS

Approximately 86% of subjects had low vitamin D status (<20 ng/mL). Mean 25(OH)D level was 14.4 ± 5.3 ng/mL with a clear seasonal dynamic and a significant negative correlation with PTH levels (r  = -0.15, p=0.006). A multiple regression analysis using the 25(OH)D cutoff value of 17 ng/mL instead of the generally admitted level of 20 ng/mL was performed to increase statistical power. Other seasons than summer (OR 4.159 and 95% CI 2.456-7.043), obesity (≥30 kg/m2, OR 1.826, 95% CI 1.081-3.083), and veiling (OR 3.526, 95% CI 1.090-11.400) were significantly associated with 25(OH)D concentrations <17 ng/mL.

CONCLUSIONS

In North Algeria, the abundant sunlight appears insufficient to fully offset hypovitaminosis D risk factors in postmenopausal women, especially obesity and veiling. It suggests the major need to increase vitamin D supplementation in this subpopulation.

Osteoporosis: Modern Paradigms for Last Century's Bones

The skeleton is a metabolically active organ undergoing continuously remodelling. With ageing and menopause the balance shifts to increased resorption, leading to a reduction in bone mineral density and disruption of bone microarchitecture. Bone mass accretion and bone metabolism are influenced by systemic hormones as well as genetic and lifestyle factors. The classic paradigm has described osteoporosis as being a “brittle bone” disease that occurs in post-menopausal, thin, Caucasian women with low calcium intakes and/or vitamin D insufficiency. However, a study of black women in Africa demonstrated that higher proportions of body fat did not protect bone health. Isoflavone interventions in Asian postmenopausal women have produced inconsistent bone health benefits, due in part to population heterogeneity in enteric bacterial metabolism of daidzein. A comparison of women and men in several Asian countries identified significant differences between countries in the rate of bone health decline, and a high incidence rate of osteoporosis in both sexes. These studies have revealed significant differences in genetic phenotypes, debunking long-held beliefs and leading to new paradigms in study design. Current studies are now being specifically designed to assess genotype differences between Caucasian, Asian, African, and other phenotypes, and exploring alternative methodology to measure bone architecture.

Is there really a relationship between serum vitamin D (25OHD) levels and the musculoskeletal pain associated with statin intake? A systematic review

INTRODUCTION

Musculoskeletal pain associated to statin use, is the most common adverse event, leading to cessation of treatment. Several studies proposed Vitamin D deficiency to increase the risk of pain associated to statin intake.

OBJECTIVES

To evaluate whether vitamin D status is linked to musculoskeletal pain associated to statin use.

METHODS

We performed a systematic review based on electronic searches through MEDLINE, Cochrane Central and EMBASE to identify studies that 1) included patients on statin therapy 2) with vitamin D serum levels assessment, 3) in relation to musculoskeletal pain.

RESULTS

The electronic search identified 127 potentially eligible studies, of which three were included and analysed in the present study. The heterogeneity of studies did not allow metanalysis. A systematic review and two cohort studies not included in the previous systematic review, revealed a statistically significant association of vitamin D deficit in patients with musculoskeletal pain on statin therapy.

CONCLUSION

The displayed evidence suggests a significant association between 25OHD serum levels<30ng/ml and the presence of musculoskeletal pain in patients on statin therapy.

Vitamin D3 supplementation in HIV infection: effectiveness and associations with antiretroviral therapy

Background

HIV infection and antiretroviral therapy (ART) may create unique risk factors for vitamin D insufficiency, including alterations of vitamin D metabolism by ART. We prospectively compared demographic and clinical parameters between vitamin D sufficient and insufficient HIV-infected (HIV+) adults, and assessed changes in these parameters among insufficient participants following standardized vitamin D supplementation.

Methods

HIV+ adults (≥18 years old) with HIV-1 RNA <50 copies/mL on ART were enrolled. Vitamin D sufficiency and insufficiency were defined as 25-hydroxyvitamin D (25(OH)D) ≥30 or <30 ng/mL, respectively. Insufficient participants received open-label vitamin D3 50,000 IU twice weekly for 5 weeks, then 8000 IU twice weekly to complete 24 weeks. The primary endpoint was success or failure to achieve 25(OH)D ≥30 ng/mL at week 24.

Results

Ninety-seven participants enrolled (34 vitamin D sufficient, 63 insufficient); 32 % female, 47 % non-White, median age 46 years, ART duration 5 years, CD4+ T lymphocyte count (CD4) 673 cells/mm³. 25(OH)D repletion was 83 % (95 % CI 71 %–90 %) successful. 25(OH)D levels correlated with both CD4 (r = 0.44, p = 0.01) and time on protease inhibitor (r = −0.35, p = 0.01). After adjusting for age, sex, race, nadir CD4 and baseline 25(OH)D: 1) current use of efavirenz exposure was associated with a 21.1 ng/mL higher week 24 25(OH)D level (p = 0.007), 2) per year use of zidovudine was associated with 7.1 ng/mL reduction in week 24 serum 25(OH)D (p = 0.05) and 3) every 1 ng/mL 25(OH)D increase was associated with a 3.3 cell/mm³ CD4 increase (p = 0.06).

Conclusion

Vitamin D₃ supplementation was effective in repleting 25(OH)D levels after 24 weeks. Current efavirenz use was positively associated with post-repletion 25(OH)D levels, while greater time on zidovudine was associated with lower post-repletion 25(OH)D levels. The association between improved CD4 recovery and vitamin D repletion suggests a potential benefit of vitamin D supplementation on immunologic recovery during HIV treatment.

Trial registration

This trial is registered at The Brazilian Clinical Trials Registry (U1111‐1165‐2537).

Electronic supplementary material

The online version of this article (doi:10.1186/s12937-015-0072-6) contains supplementary material, which is available to authorized users.