Optimal use of vitamin D when treating osteoporosis

Development of Machine Learning Models for Predicting Osteoporosis in Patients with Type 2 Diabetes Mellitus-A Preliminary Study

Purpose

Diagnosing osteoporosis in T2DM based on bone mineral density (BMD) remains challenging. We sought to develop prediction models employing machine learning algorithms for use as screening instruments for osteoporosis in T2DM patients.

Patients and Methods

Data were collected from 433 participants and analyzed using nine categorical machine learning algorithms to select features based on demographic and clinical variables. Multiple classification models were compared using the area under the receiver operating characteristic curve (ROC-AUC), accuracy, sensitivity, specificity, the average precision (AP), precision, F1 score, precision-recall curves, calibration plots, and decision curve analysis (DCA) to determine the best model. In addition, 5-fold cross-validation was utilized to optimize the model, followed by an evaluation of feature significance using Shapley Additive exPlanations (SHAP). Using latent class analysis (LCA), distinct subpopulations were identified by constructing several discrete clusters.

Results

In this study, nine feature variables were identified to construct predictive models for osteoporosis in individuals with T2DM. The machine learning algorithms achieved an AP range of 0.444-1.000. The XGBoost model was selected as the final prediction model with an AUROC of 0.940 in the training set, 0.772 in the validation set for 5-fold cross-validation, and 0.872 in the test set. Using SHAP methodology, 25(OH)D was identified as the most important risk factor. Additionally, a 3-Class model was constructed using LCA, which categorized individuals into high, medium, and low-risk groups.

Conclusion

Our study developed a predictive model with high accuracy and clinical validity for predicting osteoporosis in type 2 diabetes patients. We also identified three subpopulations with varying osteoporosis risk using clustering. However, limited sample size warrants cautious interpretation of results, and validation in larger cohorts is needed.

Challenges in osteoporosis treatment initiation in geriatric patients admitted under the hip-fracture pathway

Osteoporosis is often untreated especially in older people. This study found a low prescribing rate of osteoporosis treatment medication of 22.4% in older people admitted under the hip-fracture pathway. Factors associated with greater odds of being prescribed osteoporosis medications are categorized into patient-related, physician-related and system-related factors.

INTRODUCTION

Osteoporosis represents a growing healthcare problem which is often overlooked by healthcare providers and untreated especially in older people. This study aims to assess the rate of osteoporosis treatment initiation and to investigate underlying physician and system-related barriers in geriatric patients admitted for hip fracture.

METHODS

A retrospective study was conducted on patients aged 60 years and older, admitted under the hip-fracture pathway from January 2019 to December 2019. Data collected included demographics, co-morbid conditions and laboratory data. Clinical charts were reviewed for whether bone mineral density (BMD) scan has been ordered, plans for bone health were made and reflected in the discharge summary, and if appropriate memos were written. The primary outcome was the prescription of osteoporosis treatment medications. Prescription lists were also reviewed for prescribing patterns of calcium and vitamin D.

RESULTS

A total of 375 patients older than 60 years old were identified. 281 patients who fit the inclusion and exclusion criteria with complete data were further analysed. Within 1 year of hip fracture admission, 63 (22.4%) of them were prescribed with osteoporosis treatment. Multivariate logistic regression identified milder stage of CKD (p = 0.038, OR = 0.617, 95% CI 0.392-0.973) and BMD scan performed (p < 0.001, OR = 6.515, 95% CI 3.180-13.348) as independent factors associated with the prescription of osteoporosis treatment within 1 year of hip fracture admission.

CONCLUSION

The rate of osteoporosis treatment initiation post-hip fracture is low. Systematic solutions will need to be established to ensure that osteoporosis treatment is addressed prior to discharge.

Bone Quality in Patients with Parkinson's Disease Determined by Quantitative Ultrasound (QUS) of the Calcaneus: Influence of Sex Differences

(1) Background: Parkinson’s disease (PD) is a relatively common neurodegenerative disease in elderly individuals, with a high risk of falls. There is abundant literature on the relationship between PD and osteoporosis. The aim of this study is to describe the bone quality of a population with PD by calcaneal ultrasound and to compare it with a healthy control, assessing the influence of possible sex differences. (2) Methods: 21 patients diagnosed with PD were recruited. The control group was composed of 30 healthy individuals with similar sociodemographic characteristics. The bone quality of all participants was assessed using calcaneal quantitative ultrasound (QUS). The parameters recorded were broadband ultrasound attenuation (BUA, in decibels per megahertz), imaging speed of sound (SOS, in meters per second), stiffness index (SI) and T-score of each participant. Bone mineral density (BMD) was estimated using the equation BMD = 0.002592 × (BUA + SOS) − 3.687 (g/cm2). (3) Results: significant differences were observed between the healthy control and the PD group: the T-score was lower in the PD group (p < 0.05) and SOS was higher in Parkinson’s disease patients (p < 0.05), while 28.6% of the PD patients were osteoporotic with T-score values lower than −1.5 compared to 16.7% of osteoporotic individuals in the control group (p < 0.01). Regarding the sex, there were significant differences (p < 0.05) between the females of the PD group vs. control group, showing a significant difference in the SI (71.4 ± 14.7 vs. 87.8 ± 12), T-score (−2.19 ± 1.1 vs. −0.15 ± 0.8), BUA (104.5 ± 13 vs. 116 ± 10.6) and BMD (0.49 ± 0.09 vs. 0.60 ± 0.08), with no difference in the comparison between the male groups; and the comparison between both sexes in T-score only showed significant differences for the PD group (p < 0.05), with worse bone quality in women. (4) Conclusions: this study shows poorer bone quality in female patients with PD, who have a higher percentage of osteoporosis than healthy patients. The QUS technique of the calcaneus seems adequate for these determinations in patients with Parkinson’s disease.

Vitamin D Status Is Negatively Related to Insulin Resistance and Bone Turnover in Chinese Non-Osteoporosis Patients With Type 2 Diabetes: A Retrospective Cross-Section Research

Background and Objectives

Vitamin D status is closely related to blood glucose and bone metabolism in patients with type 2 diabetes (T2DM). Vitamin D affects bone density and bone metabolism, leading to osteopenia and osteoporosis. Insulin resistance increases the risk of osteoporosis in patients with T2DM. Our previous studies have shown a negative correlation between insulin resistance and 25-hydroxy vitamin D [25(OH)D] levels. The aim of the present study was to determine the association between vitamin D status and insulin resistance and bone metabolism in patients with T2DM.

Subjects and Methods

A retrospective cross-section research was carried out among 109 non-osteoporosis patients with T2DM. Their fasting blood glucose (FBG), 25(OH)D, fasting blood insulin (FINS), glycosylated hemoglobin (HbA1c), serum creatinine (SCr), calcium (Ca), phosphorus (P), insulin-like growth factor-1 (IGF-1), bone alkaline phosphatase (BALP), body mass index (BMI), glomerular filtration rate (eGFR), homeostatic model estimates of insulin resistance (HOMA-IR), and calcium-phosphorus product were measured routinely.

Results

Both in men and women, 25(OH)D was negatively correlated with BALP (β = −0. 369, p ≤ 0.001)and HOMA-IR (β = −0.349, p ≤ 0.001), and positively associated with IGF-1(β = 0.672, p ≤ 0.05). There was a negative correlation between HOMA-IR and IGF-1 (β = −0.464, p ≤ 0.001), and a positive correlation between HOMA-IR and BALP (β = 0.344, p ≤ 0.05), adjusted by confounding factors.

Conclusion

Our study demonstrates that 25(OH)D concentrations are negatively correlated with insulin resistance and bone turnover. Insulin resistance increases with the decrease of 25(OH)D concentration, which can enhance bone turnover, and increases the risk of osteoporosis in non-osteoporosis patients with T2DM. This is the first study to clarify the relationship between serum vitamin D status, insulin resistance, and bone metabolism in non-osteoporosis patients with T2DM in China.

Amino acid requirements for laying hens: a comprehensive review

The main aim of this review is to consolidate the relevant published data examining amino acid requirements of layer hens and to reach a new set of recommendation based on these data. There are inconsistences in lysine, sulphur-containing amino acids, threonine, tryptophan, branched-chain amino acids, and arginine recommendations in data that have surfaced since 1994. This review finds that breed, age, basal diet composition, and assessment method have contributed toward inconsistencies in amino acid recommendations. Presently, the development of reduced-protein diets for layer hens is receiving increasing attention because of the demand for sustainable production. This involves quite radical changes in diet composition with inclusions of nonbound, essential and nonessential amino acids. Increasing inclusions of nonbound amino acids into layer diets modifies protein digestive dynamics, and it may influence amino acid requirements in layer hens. This review considers present amino acid recommendations for layer hens and proposes refinements that may better serve the needs of the layer industry in the future.

Managing Genetic Hemochromatosis: An Overview of Dietary Measures, Which May Reduce Intestinal Iron Absorption in Persons With Iron Overload

Genetic hemochromatosis causes iron overload by excess absorption of dietary iron, due to a decreased expression of hepcidin. The objective was to elaborate dietary recommendations that can reduce intestinal iron absorption in hemochromatosis patients, based on our present knowledge of the iron contained in nutrients and the mechanisms of iron uptake. This is a narrative review. Literature search in PubMed and Google Scholar of papers dealing with iron absorption from the diet was conducted. Most important proposed dietary recommendations are: 1) Choose a varied vegetarian, semi-vegetarian or flexitarian diet. A “veggie-lacto-ovo-poultry-pescetarian” diet seems optimal. Avoid iron enriched foods and iron supplements. 2) Eat many vegetables and fruits, at least 600 g per day. Choose protein rich pulses and legumes (e.g., kidney- and soya beans). Fresh fruits should be eaten between meals. 3) Abstain from red meat from mammals and choose the lean, white meat from poultry. Avoid processed meat, offal and blood containing foods. Eat no more than 200 g meat from poultry per week. Choose fish, eggs, vegetables and protein rich legumes the other days. Eat fish two to four times a week as main course, 350 - 500 g fish per week, of which half should be fat fish. 4) Choose whole grain products in cereals and bread. Avoid iron enriched grains. Choose non-sourdough, yeast-fermented bread with at least 50% whole grain. 5) Choose vegetable oils, and low-fat dairy products. 6) Eat less sugar and salt. Choose whole foods and foods with minimal processing and none or little added sugar or salt. 7) Quench your thirst in water. Drink green- or black tea, coffee, or low-fat milk with the meals, alternatively water or non-alcoholic beer. Fruit juices must be consumed between meals. Abstain from alcoholic beverages. Drink soft drinks, non-alcoholic beer, or non-alcoholic wine instead. These advices are close to the official Danish dietary recommendations in 2021. In the management of hemochromatosis, dietary modifications that lower iron intake and decrease iron bioavailability may provide additional measures to reduce iron uptake from the foods and reduce the number of phlebotomies. However, there is a need for large, prospective, randomized studies that specifically evaluate the effect of dietary interventions.

Comparisons of different vitamin D supplementation for prevention of osteoporotic fractures: a Bayesian network meta-analysis and meta-regression of randomised controlled trials

Previous randomised controlled trials have shown the controversial effectiveness of oral vitamin D supplementation in preventing osteoporotic fractures. PubMed, EMBASE and Cochrane Library electronic databases were searched. Pairwise meta-analysis, Bayesian network meta-analysis and meta-regression were applied. A total of 33 studies containing 83,083 participants were included. Oral vitamin D supplementation showed no statistically significant on reducing the risk of total fractures (RR = 0.96, 95%CI = 0.87-1.05 p = 0.389). Vitamin D₃ (700-800IU/d) plus calcium showed statistical significance in reducing the incidence of total, hip and non-vertebral fractures in the pairwise meta-analysis. Significant reductions were specifically identified in female in total and hip fractures. However, we did not observe any above significant results using Bayesian network meta-analyses. Strikingly, a meta-regression analysis identified an inverse association between the efficacy of fracture prevention and increased body mass index. Thus, we recommended that the vitamin D dose should be adjusted according to BMI based on further confirmation.

Assessing the Effectiveness of Panchatikta Ghrita, a Classical Ayurvedic Formulation as Add-on Therapy to Vitamin D3 and Calcium Supplements in Patients with Osteopenia: A Randomized, Open-Labeled, Comparative, Controlled Clinical Study

Objectives: To assess the change in the bone mineral density (BMD) score, bone-specific biomarkers (serum vitamin D₃, tartrate-resistant acid phosphatase 5b [TRAP-5b], and osteocalcin), quality of life, Ayurvedic symptoms (Asthikshaya Lakshanas), and fracture risk assessment tool (FRAX) scores following treatment with Panchatikta Ghrita (PG), a classical herbal formulation as add-on therapy to calcium and vitamin D₃ supplements. Study design: Randomized, open-labeled, comparative, controlled clinical study. Location: TN Medical College and BYL Nair Hospital, Mumbai, India. Study participants: Eighty adult patients, aged between 40 and 75 years, diagnosed to have osteopenia (BMD T-score between -1 and -2.5 in at least two of the three joints tested-lumbar spine L1-L4, left femur-neck, left forearm-radius total). Study intervention: Treatment group received two tablespoons of PG (10 mL in lukewarm milk) along with calcium and vitamin D₃ supplements twice a day, whereas control group received only calcium and vitamin D₃ supplements twice a day for a period of 12 months. Outcome measures: BMD, bone-specific biomarkers (vitamin D₃, TRAP-5b, and osteocalcin), quality of life, Ayurvedic symptoms, and FRAX scores were evaluated before and at 6 and 12 months. Results: Eighty patients were enrolled; of which, 65 patients completed the study while 15 patients dropped out. Improvement in the BMD scores was observed at 6 and 12 months with the maximum benefit in the lumbar spine region. Significant improvement in the bone-specific biomarkers, namely serum vitamin D₃ (p < 0.001), osteocalcin (p < 0.001), and TRAP-5b (p < 0.05), was observed in the PG-treated group compared with the standard treatment group. Improvement in the quality of life, Ayurvedic symptoms scores, and risk reduction in FRAX scores of major osteoporotic fracture risk and hip fracture risk was greater with PG, although not statistically significant. Conclusions: The study findings demonstrate that PG slows down the bone degeneration processes by its stabilizing effect on the bone-specific biomarkers, indicating its potential usefulness as preventive therapy in osteopenia. The positive improvement noted in this study needs to be confirmed in studies with a larger sample size and longer duration.

The role of the Fracture Liaison Service (FLS) in subsequent fracture prevention in the extreme elderly

BACKGROUND

Several guidelines recommend a bone and fall-related osteoporosis risk assessment in all patients with fracture and age > 50 years. In practice, however, there is no consensus whether screening > 85 years is useful.

AIM

To evaluate the subsequent fracture risk in all patient > 85 years, comparing the two populations of Fracture Liaison Service (FLS) attenders and non-attenders.

METHODS

All patients > 85 years that presented at the FLS with a non-vertebral fracture were included in the study during a 5-year period (September 2004 and December 2009). Excluded were pathologic fractures, death < 30 days, or patients on osteoporosis treatment. in patients that attended the FLS, assessment of bone mineral density and fall-risk factors were screened. In both the attenders and non-attenders groups, mortality and subsequent fracture rates were scored during a follow-up of 2 years.

RESULTS

282 patients fulfilled inclusion criteria for screening, of which 160 (57%) patients did not attend the FLS. 122 patients were screened for osteoporosis and fall-related risk of whom 72 were diagnosed with osteoporosis. Subsequent fracture risk in both groups was 19%. Medical treatment was started in 51 patients, of which 15 patients developed a subsequent fracture. Cox-regression analysis indicated a significantly lower mortality rate, but not a diminished subsequent fracture rate in the FLS screened population compared to the non-attenders.

CONCLUSION

The advantage of a FLS in reducing subsequent fracture risk in patients > 85 years seems to be limited. In practice a large proportion of these patients are not screened.

Bone mass and vitamin D levels in Parkinson's disease: is there any difference between genders?

[Purpose] The aim of this study was to determine the bone mineral density, vitamin D level, and frequencies of osteopenia and osteoporosis in patients with Parkinson's disease and to compare male and female patients with the controls separately. [Subjects and Methods] One hundred fifteen Parkinson's disease patients (47 males, 68 females; age range: 55-85 years) and 117 age- and gender-matched controls (47 males, 70 females) were enrolled in the study. Bone mineral density measured by dual-energy X-ray absorptiometry and serum D vitamin levels of each participant were recorded. [Results] The mean lumbar spine, femur neck, and total femur bone mineral density levels, T-scores, and vitamin D levels were found to be significantly lower in Parkinson's disease patients in both genders. Furthermore, osteoporosis rates were found be significantly higher only in female Parkinson's disease patients compared with female controls. [Conclusion] Data from the present study revealed that while osteoporosis was significantly higher only in female Parkinson's disease patients, all Parkinson's disease patients had lower bone mineral density scores and vitamin D levels compared with the controls regardless of gender, suggesting that clinicians should pay attention to the osteoporosis risk in Parkinson's disease and that adequate preventive measures should be taken in order to limit the future risk due to osteoporotic fractures.

1,25(OH)2D3 Deficiency Induces Colon Inflammation via Secretion of Senescence-Associated Inflammatory Cytokines

Epidemiological studies showed that 1,25-Dihydroxyvitamin D[1,25(OH)2D3] insufficiency appears to be associated with aging and colon cancer while underlying biological mechanisms remain largely unknown. Inflammatory bowel disease is one of the risk factors for colon cancer. In this study, we investigated whether 1,25(OH)2D3 deficiency has an impact on the colon of 25-hydroxyvitamin D 1α-hydroxylase knockout [Cyp27b1(-/-)] mice fed on a rescue diet (high calcium, phosphate, and lactose) from weaning to 10 months of age. We found that 1,25(OH)2D3 deficient mice displayed significant colon inflammation phenotypes including shortened colon length, thinned and disordered mucosal structure, and inflammatory cell infiltration. DNA damage, cellular senescence and the production of senescence-associated inflammatory cytokines were also increased significantly in the colon of Cyp27b1(-/-)mice. Furthermore, the levels of ROS in the colon were increased significantly, whereas the expression levels of antioxidative genes were down-regulated dramatically in the colon of Cyp27b1(-/-)mice. Taken together, our results demonstrated that 1,25(OH)2D3 deficiency could induce colon inflammation, which may result from increased oxidative stress and DNA damage, subsequently, induced cell senescence and overproduction of senescence-associated secretory factors. Therefore, our findings suggest that 1,25(OH)2D3 may play an important role in preventing the development and progression of colon inflammation and colon cancer.

Relationship of low vitamin D status with positive, negative and cognitive symptom domains in people with first-episode schizophrenia

AIM

Deficient vitamin D levels are very common among Americans of all ages and ethnicities, but little is known about its prevalence or associated problems among those with schizophrenia.

METHODS

Stored plasma from 20 recent onset schizophrenia subjects and 20 matched healthy comparison subjects were analysed for 25 OH vitamin D, and related to measures of symptom severity and neurocognition.

RESULTS

There was no significant difference in mean 25 OH vitamin D between the schizophrenia and the healthy comparison subjects (28.2 standard deviation (SD) 12.6 ng mL(-1) vs. 29.9 SD 14.3 ng mL(-1) ), and about half the subjects in each group had insufficient levels (<30 ng mL(-1) ). Among psychosis subjects, greater severity of negative symptoms was correlated with lower vitamin D status (r = -0.55, P = 0.012); the correlations of overall symptom severity and positive symptom severity with 25 OH vitamin D levels approached significance (r = -0.42, P = 0.07 and r = -0.36, P = 0.12, respectively). There was no relationship of vitamin D with depressive symptoms. Among the schizophrenia subjects, lower 25 OH vitamin D levels were associated with more severe overall cognitive deficits (r = 0.56, P = 0.019).

CONCLUSION

This study found that lower vitamin D levels in schizophrenia subjects were associated with more severe negative symptoms and overall cognitive deficits. However, the cross-sectional design precludes any conclusions about whether low vitamin D status in fact causes more severe negative symptoms and cognitive impairments. No relationship was found between lower vitamin D levels and depressive symptoms.

Fracture prevention in COPD patients; a clinical 5-step approach

Although osteoporosis and its related fractures are common in patients with COPD, patients at high risk of fracture are poorly identified, and consequently, undertreated. Since there are no fracture prevention guidelines available that focus on COPD patients, we developed a clinical approach to improve the identification and treatment of COPD patients at high risk of fracture. We organised a round-table discussion with 8 clinical experts in the field of COPD and fracture prevention in the Netherlands in December 2013. The clinical experts presented a review of the literature on COPD, osteoporosis and fracture prevention. Based on the Dutch fracture prevention guideline, they developed a 5-step clinical approach for fracture prevention in COPD. Thereby, they took into account both classical risk factors for fracture (low body mass index, older age, personal and family history of fracture, immobility, smoking, alcohol intake, use of glucocorticoids and increased fall risk) and COPD-specific risk factors for fracture (severe airflow obstruction, pulmonary exacerbations and oxygen therapy). Severe COPD (defined as postbronchodilator FEV₁ < 50% predicted) was added as COPD-specific risk factor to the list of classical risk factors for fracture. The 5-step clinical approach starts with case finding using clinical risk factors, followed by risk evaluation (dual energy X-ray absorptiometry and imaging of the spine), differential diagnosis, treatment and follow-up. This systematic clinical approach, which is evidence-based and easy-to-use in daily practice by pulmonologists, should contribute to optimise fracture prevention in COPD patients at high risk of fracture.

Relationship between serum leptin levels and bone mineral density: a systematic review and meta-analysis

BACKGROUND

The association between leptin and bone mineral density (BMD) is controversial because of conflicting findings from previous studies.

METHODS

This meta-analysis aimed to provide an overview of the serum leptin levels and BMD in a healthy population. We reviewed the PubMed, Embase, and Cochrane Library databases until July 2014 for research on the association between leptin levels and BMD in healthy people.

RESULTS

We included and analyzed 45 studies in this systematic review and meta-analysis. The pooled correlations between leptin and BMD were analyzed by using the method of the inverse of the variance. Leptin was positively associated with BMD and the bone mineral content (BMC), especially in postmenopausal women (pooled r: 0.13-0.49). Overall, high serum leptin levels were associated with higher BMD levels.

CONCLUSIONS

This meta-analysis suggests that serum leptin levels are positively associated with BMD and BMC, especially in postmenopausal women.

A meta-analysis of high dose, intermittent vitamin D supplementation among older adults

BACKGROUND

The effects of intermittent, high dose vitamin D treatment in older adults have not been documented. We conducted a meta-analysis to provide a quantitative assessment of the efficiency of intermittent, high dose vitamin D treatment on falls, fractures, and mortality among older adults.

METHODS

Electronic databases were searched for randomized controlled trials (RCTs) on high dose, intermittent vitamin D supplementation among older adults. Two researchers independently screened the literature according to specified inclusive and exclusive criteria to extract the data. Meta-analysis was performed by using Review Manager 5.1.0 software.

RESULTS

Nine trials were included in this meta-analysis. High dose, intermittent vitamin D therapy did not decrease all-cause mortality among older adults. The risk ratio (95% CI) was 1.04 (0.91-1.17). No benefit was seen in fracture or fall prevention. The risk ratio for hip fractures (95% CI) was 1.17 (0.97-1.41) while for non-vertebral fractures (95% CI) it was 1.06 (0.91-1.22), and the risk ratio for falls (95% CI) was 1.02 (0.96-1.08). Results remained robust after sensitivity analysis.

CONCLUSION

Supplementation of intermittent, high dose vitamin D may not be effective in preventing overall mortality, fractures, or falls among older adults. The route of administration of vitamin D supplements may well change the physiological effects.

The Role of Vitamin D in the Aging Adult

The number of individuals aged 65 and older is expected to more than double from 2012 to 2060. The role of vitamin D in the prevention and treatment of diseases associated with aging has not been well studied. Traditionally, the role of vitamin D focused on the maintenance of skeletal health in the older adult. With the discovery of vitamin D receptors in the nervous, cardiovascular and endocrine systems, the role of vitamin D and its impact on these systems has become an important area of research. Older adults are at risk for lower levels of vitamin D as a result of decreased cutaneous synthesis and dietary intake of vitamin D. Epidemiologic evidence indicates an association between low levels of vitamin D and diseases associated with aging such as cognitive decline, depression, osteoporosis, cardiovascular disease, hypertension, type 2 diabetes, and cancer. Clinical trials to determine the benefit of vitamin D supplementation in preventing and treating such diseases are in progress. This paper highlights current evidence regarding the role that vitamin D may play in diseases associated with aging and addresses the need for well-designed randomized trials to examine its benefit on health outcomes in the older adult.

Calcium and vitamin D supplementation: state of the art for daily practice

BACKGROUND

Calcium and vitamin D play an essential role in bone metabolism but deficiency and/or inadequate intake are common.

OBJECTIVES

To describe a practical approach based on the literature regarding clinically important aspects of calcium and vitamin D supplementation.

METHODS

A systematic evaluation of relevant literature in Medline was conducted. We included physiological studies, publications on relevant guidelines, meta-analysis, randomized clinical trials, and cohort studies.

RESULTS

An adequate calcium intake and vitamin D supplementation is recommended in most guidelines xon fracture prevention. Daily supplementation with 800 IU is advocated in most guidelines, appears to be safe, and with this approach it is generally not necessary to determine vitamin D levels. There are no data on additional effects of loading doses of vitamin D on fracture or fall prevention. Calcium supplementation should be tailored to the patient's need: usually 500 mg per day is required. The intestinal absorption of calcium citrate is approximately 24% better than that of calcium carbonate independent of intake with meals. Data on difference between calcium absorption with calcium carbonate compared to calcium citrate with simultaneous use of proton pump inhibitors are lacking. Concern has arisen about a possible link between calcium supplementation and an increased risk of myocardial infarction. Probably only well-designed prospective randomized controlled trials will be able to allow definite conclusions on this subject.

CONCLUSION

Daily supplementation with 800 IU vitamin D is a practical and safe strategy without the need for prior determination of vitamin D levels. Calcium supplementation should be tailored to the patient's need based on total daily dietary calcium intake. In most patients 500 mg per day is required to achieve a total intake of 1,200 mg, or in some 1,000 mg per day. More calcium is absorbed from calcium citrate compared to calcium carbonate.

Meta-analysis of long-term vitamin D supplementation on overall mortality

Introduction

It has been suggested that vitamin D is effective to prevent mortality. However, there is no consistent conclusion that the effects of vitamin D supplementation on all-cause mortality are associated with duration of treatment. We conducted a meta-analysis regarding this issue in an effort to provide a more robust answer.

Methods

A comprehensive search in a number of databases, including MEDLINE, Embase and The Cochrane Central Register of Controlled Trials, was conducted for collecting randomized controlled trials (RCTs) on vitamin D supplementation preventing mortality. Two investigators independently screened the literature according to the inclusive and exclusive criteria and the relative data were extracted. Data analysis was performed by using Review Manager 5.0 software.

Results

Data from forty-two RCT s were included. Vitamin D therapy significantly decreased all-cause mortality with a duration of follow-up longer than 3 years with a RR (95% CI) of 0.94 (0.90–0.98). No benefit was seen in a shorter follow-up periods with a RR (95% CI) of 1.04 (0.97–1.12). Results remain robust after sensitivity analysis. The following subgroups of long-term follow-up had significantly fewer deaths: female only, participants with a mean age younger than 80, daily dose of 800 IU or less, participants with vitamin D insufficiency (baseline 25-hydroxyvitamin D level less than 50 nmol/L) and cholecalciferol therapy. In addition, the combination of vitamin D and calcium significantly reduced mortality and vitamin D alone also had a trend to decrease mortality in a longer time follow up.

Conclusions

The data suggest that supplementation of vitamin D is effective in preventing overall mortality in a long-term treatment, whereas it is not significantly effective in a treatment duration shorter than 3 years. Future studies are needed to identify the efficacy of vitamin D on specific mortality, such as cancer and cardiovascular disease mortality in a long-term treatment duration.

Osteoporosis in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is being regarded as a heterogeneous disease with clinically significant pulmonary and extrapulmonary manifestations, such as emphysema, cardiovascular disease and osteoporosis. Osteoporosis is characterized by low bone mass and microarchitectural deterioration of bone tissue, leading to enhanced bone fragility and, consequently, an increased risk of fracture. Fractures resulting from osteoporosis might contribute to increased morbidity and mortality, particularly in COPD patients. The high prevalence of osteoporosis in COPD patients is assumed to be due to common risk factors, such as older age and tobacco smoking, and COPD-specific risk factors, such as systemic inflammation, vitamin D deficiency and the use of oral or inhaled corticosteroids. This review provides a state-of-the-art summary of the prevalence, pathophysiology, diagnosis, risk factors and treatment of osteoporosis in COPD patients. It also discusses potential mechanisms linking COPD with osteoporosis.

Osteoporosis risk and bone mineral density levels in patients with Parkinson's disease: a meta-analysis

INTRODUCTION

Parkinson's disease (PD) and osteoporosis are common diseases which affect a substantial portion of the elderly population. Accumulating evidence supports that PD patients have a high risk for osteoporosis in recent years. The purpose of the present study is to perform a meta-analysis on the risk of osteoporosis and bone mineral density (BMD) levels in PD patients.

METHODS

We searched all articles indexed in Medline, SciVerse Scopus and Cochrane Library published up to January 2012 concerning the association between PD and risk of osteoporosis or BMD levels. In total, 15 studies were included in the meta-analysis.

RESULTS

The results indicated that PD patients are at higher risk for osteoporosis (summary OR=1.18, 95% CI=[1.09, 1.27]) than healthy controls. The gender subgroup analysis suggested that PD male patients have a higher risk for osteoporosis than female patients (female patients: summary OR=1.16, 95% CI=[1.07, 1.26]; male patients: summary OR=2.44, 95% CI=[1.37, 4.34]). Further meta-analysis showed that PD patients have a lower hip, lumbar spine and femoral neck BMD than healthy controls. The gender subgroup analysis found a lower BMD in PD female patients than controls, while no obvious difference was observed in PD male patients and controls.

CONCLUSIONS

This meta-analysis suggested that PD patients are at higher risk for osteoporosis and have lower BMD levels than healthy controls overall.

Alzheimer's disease and risk of hip fracture: a meta-analysis study

Background. Alzheimer's disease (AD) is the most common cause of dementia in the elderly population. Growing evidence supports that AD patients are at high risk for hip fracture, but the issue remains questionable. The purpose of the present study is to perform a meta-analysis to explore the association between AD and risk of hip fracture. Considering that bone mineral density (BMD) acts as a strong predictor of bone fracture, we also studied the hip BMD in AD patients. Methods. We searched all publications in Medline, SciVerse Scopus, and Cochrane Library published up to January 2012 about the association between AD and hip fracture or hip BMD. Results. There are 9 studies included in the meta-analysis. The results indicate that AD patients are at higher risk for hip fracture (OR and 95% CI fixed: ES = 2.58, 95% CI = [2.03, 3.14]; dichotomous data: summary OR = 1.80, 95% CI = [1.54, 2.11]) than healthy controls. Further meta-analysis showed that AD patients have a lower hip BMD (summary SMD = −1.12, 95% CI = [−1.34, −0.90]) than healthy controls. Conclusions. It was found that in comparison with healthy controls AD patients are at higher risk for hip fracture and have lower hip BMD.

Vitamin D in the new millennium

The incidence of vitamin D deficiency is rising worldwide, yet in the vast majority of patients, the condition remains undiagnosed and untreated. Current evidence overwhelmingly indicates that supplemental doses greater than 800 IU/day have beneficial effects on the musculoskeletal system, improving skeletal homeostasis, thus leading to fewer falls and fractures. Evidence is also accumulating on the beneficial effects of vitamin D on extraskeletal systems, such as improving immune health, autoimmune disorders, cancer, neuromodulation, diabetes, and metabolic syndrome. The cause-effect relationship of vitamin D deficiency with increasing incidences of nonskeletal disorders is being investigated. Published reports support the definition of sufficiency, serum levels of 25-hydroxyvitamin D [25(OH)D] greater than 30 ng/mL (75 nmol/L). To achieve this, most people need vitamin D supplementation ranging from 600 to 2000 IU/day; consumption up to of 5000 international units (IU) per day of vitamin D is reported as safe. Although light-skinned individuals need 1000 IU/day of vitamin D, elderly and dark-skinned individuals are likely to need approximately 2000 IU/day to maintain serum 25(OH)D levels greater than 30 ng/mL. Other vulnerable patients, such as the obese, those who have undergone bariatric surgery, and those with gastrointestinal malabsorption syndromes, may require higher doses of vitamin D to maintain normal serum levels and be healthy.

Does vitamin D protect against DNA damage?

Vitamin D is a secosteroid best known for its role in maintaining bone and muscle health. Adequate levels of vitamin D may also be beneficial in maintaining DNA integrity. This role of vitamin D can be divided into a primary function that prevents damage from DNA and a secondary function that regulates the growth rate of cells. The potential for vitamin D to reduce oxidative damage to DNA in a human has been suggested by clinical trial where vitamin D supplementation reduced 8-hydroxy-2'-deoxyguanosine, a marker of oxidative damage, in colorectal epithelial crypt cells. Studies in animal models and in different cell types have also shown marked reduction in oxidative stress damage and chromosomal aberrations, prevention of telomere shortening and inhibition of telomerase activity following treatment with vitamin D. The secondary function of vitamin D in preventing DNA damage includes regulation of the poly-ADP-ribose polymerase activity in the DNA damage response pathway involved in the detection of DNA lesions. It is also able to regulate the cell cycle to prevent the propagation of damaged DNA, and to regulate apoptosis to promote cell death. Vitamin D may contribute to prevention of human colorectal cancer, though there is little evidence to suggest that prevention of DNA damage mediates this effect, if real. Very limited human data mean that the intake of vitamin D required to minimise DNA damage remains uncertain.

Calcium and vitamin D controversies

Controversies regarding appropriate use of vitamin D and calcium are predominately related to the extraskeletal effects. Calcium and vitamin D are essential for bone health. The concerns regarding calcium and cardiovascular complications are inconclusive at best, and do not warrant a change in our approach to supplementation at this time. A growing body of literature exists suggesting that additional vitamin D may have numerous benefits, although more study needs to be done. Further prospective trials would provide insight into the potential advantages that increased vitamin D supplementation could provide.

Vitamin D status in patients with chronic plaque psoriasis

BACKGROUND

Vitamin D could have important immunomodulatory effects in psoriasis.

OBJECTIVES

To measure 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH) and calcium serum levels in patients with psoriasis and the associations with some relevant clinical features.

METHODS

A cross-sectional study was conducted over 1 year including 145 patients with chronic plaque psoriasis, 112 patients with rheumatoid arthritis (RA) and 141 healthy controls. 25(OH)D, PTH and calcium serum levels were measured in a centralized laboratory. Demography, comorbidities, disease severity and exposure time to sunlight (which was derived by questionnaire) were collected.

RESULTS

The prevalence of vitamin D deficiency [25(OH)D levels <20ngmL(-1) ] in patients with psoriasis was 57·8% vs. 37·5% in patients with RA and 29·7% in healthy controls (P<0·001). In winter, the prevalence of vitamin D deficiency rose to 80·9% in patients with psoriasis, to 41·3% in those with RA and to 30·3% in healthy controls (P<0·001). Patients with psoriasis or psoriatic arthritis did not differ in 25(OH)D serum levels nor in the prevalence of vitamin D deficiency. In the logistic regression analysis, vitamin D deficiency was associated with psoriasis independently of age, sex, body mass index, calcium, PTH levels and season of blood sampling. A limitation is that the study design does not allow a causal or temporal relationship between vitamin D deficiency and psoriasis to be established.

CONCLUSIONS

Vitamin D deficiency may be common in patients with psoriasis, especially in winter.

Osteoporosis, frailty and fracture: implications for case finding and therapy

In almost all patients with incident fractures, the absolute risk of subsequent fracture and mortality is highest immediately after the fracture is incurred; the risk is substantially increased in frail elderly patients. The risk factors for incident fractures, such as bone fragility, tendency to fall and the presence of metabolic bone disease, remain underdiagnosed and undertreated. Here, we review the evidence that demonstrates the influence of these risk factors on susceptibility to subsequent fracture and mortality after an incident fracture, and discuss the tools available to predict these outcomes. In this Review, we also propose a systematic, coordinator-based approach to assessment of risk, allocation of treatment and follow-up in all patients over 50 years of age who present with a fracture. The aim of this proposed multistep procedure is to improve the prevention of secondary fracture, decrease mortality rates and reduce patient undertreatment or overtreatment.