Vitamin D and Physical Function in Sedentary Older Men

Vitamin D supplementation and falls in residential aged care: A longitudinal multisite cohort study

Background

Vitamin D is vital for musculoskeletal health, and supplementation may lower risk of falls. Past research in residential aged care (RAC) settings on the effects of vitamin D on falls have reported inconclusive findings, partly due to study design limitations. We utilised a longitudinal study design to assess the association between the use of vitamin D and falls over 36 months in RAC.

Method

A longitudinal cohort study was conducted using routinely collected electronic data spanning 9 years from 27 RAC facilities in Sydney, New South Wales, Australia. The study included 4520 permanent residents aged 65 years or older who were admitted for the first time from 1 July 2014 and stayed for a minimum of one month. We identified daily vitamin D usage over 36 months, and measured adherence using the Proportion of Days Covered (PDC) metric. A PDC value of ≥80 % signifies optimal adherence. Primary outcomes were the number of all falls and injurious falls. A rolling time-varying predictor-outcome approach and Generalized Estimating Equations (GEE) were applied to determine the longitudinal link between vitamin D supplement use and subsequent risk of falls.

Results

Over two-thirds of residents (67.8 %; n = 3063) received vitamin D supplements during their stay, with a median PDC of 74.8 % among users, and 44.6 % (n = 1365) achieving optimal adherence. Increasing age, osteoporosis or fracture history, and dementia were associated with a greater likelihood of achieving optimal adherence. Crude fall incident rates were 8.05 and 2.92 incidents per 1000 resident days for all falls and injurious falls respectively. After accounting for relevant demographic and clinical factors, no significant links were observed between vitamin D supplement usage and fall outcomes: all falls (Incident Rate Ratio [IRR] 1.01; 95 % CI 1.00-1.02; P = 0.237) and injurious falls (IRR 1.01; 95 % CI 1.00-1.02; P = 0.091).

Conclusion

Vitamin D supplementation was not associated with a reduced risk of falls, suggesting it is not an effective intervention for preventing falls in RAC. While clinicians should ensure adequate vitamin D intake for residents' nutritional and bone health, it should not be a standalone falls prevention intervention in RAC populations.

Renin angiotensin system-induced muscle wasting: putative mechanisms and implications for clinicians

Renin angiotensin system (RAS) alters various mechanisms related to muscle wasting. The RAS system consists of classical and non-classical pathways, which mostly function differently. Classical RAS pathway, operates through angiotensin II (AngII) and angiotensin type 1 receptors, is associated with muscle wasting and sarcopenia. On the other hand, the non-classical RAS pathway, which operates through angiotensin 1-7 and Mas receptor, is protective against sarcopenia. The classical RAS pathway might induce muscle wasting by variety of mechanisms. AngII reduces body weight, via reduction in food intake, possibly by decreasing hypothalamic expression of orexin and neuropeptide Y, insulin like growth factor-1 (IGF-1) and mammalian target of rapamycin (mTOR), signaling, AngII increases skeletal muscle proteolysis by forkhead box transcription factors (FOXO), caspase activation and muscle RING-finger protein-1 transcription. Furthermore, AngII infusion in skeletal muscle reduces phospho-Bad (Ser136) expression and induces apoptosis through increased cytochrome c release and DNA fragmentation. Additionally, Renin angiotensin system activation through AT1R and AngII stimulates tumor necrosis factor-α, and interleukin-6 which induces muscle wasting, Last but not least classical RAS pathway, induce oxidative stress, disturb mitochondrial energy metabolism, and muscle satellite cells which all lead to muscle wasting and decrease muscle regeneration. On the contrary, the non-classical RAS pathway functions oppositely to mitigate these mechanisms and protects against muscle wasting. In this review, we summarize the mechanisms of RAS-induced muscle wasting and putative implications for clinical practice. We also emphasize the areas of uncertainties and suggest potential research areas.

Effect of vitamin D, calcium, or combined supplementation on fall prevention: a systematic review and updated network meta-analysis

BACKGROUND

The association between vitamin D supplementation and the risk of falls in older adults has been controversial. This systematic review and network meta-analysis aims to assess the efficacy of vitamin D, calcium, and combined supplementation in the prevention of falls.

METHODS

Randomized controlled trials (RCTs) on the efficacy of vitamin D in fall prevention were systematically searched in PubMed, Embase, Cochrane Library, and Web of Science from inception to May 9, 2023. The network meta-analysis was performed using a random effects model in R4.1.3 and Stata15.0. Heterogeneity was evaluated by the I2 statistic, and publication bias was assessed using funnel plots, Begg's test, and Egger's tests. Data were pooled and expressed as relative risk (RR) and 95% confidence interval (CI).

RESULTS

A total of 35 RCTs involving 58,937 participants were included in this study, among which 11 RCTs (31.4%) applied calcium combined with vitamin D. There was low heterogeneity (I2 = 11%) among the included studies. Vitamin D supplementation at 800-1000 International Unit (IU)/d resulted in a lower risk of falls than placebo or no treatment (RR = 0.85, 95%CI: 0.74-0.95). In addition, 800-1000 IU/d of vitamin D with or without calcium were more effective in preventing falls than calcium alone. High-dose vitamin D (> 1000 IU/day) increased the risk of falls compared with 800-1000 IU/d of vitamin D. According to the subgroup analysis, daily administration of 800-1000 IU/d vitamin D was associated with a 22% reduction in the risk of falls (RR = 0.78, 95%CI:0.64-0.92), whereas intermittent vitamin D administration had no preventive effect. Furthermore, 800-1000 IU/d of vitamin D also significantly decreased the risk of falls in old adults with ≤ 50 nmol/L 25-hydroxyvitamin D [25(OH)D] (RR = 0.69, 95%CI:0.52-0.86) but not in individuals with > 50 nmol/L 25(OH)D.

CONCLUSION

Vitamin D supplementation at 800-1000 IU/d is associated with a lower risk of falls among older adults. 800-1000IU/d of vitamin D has a benefit on prevention of falls in population received daily dose regimens and in population with vitamin D deficiency.

Effects of Supplemental Vitamin D3, Omega-3 Fatty Acids on Physical Performance Measures in VITamin D and OmegA-3 TriaL

CONTEXT

Declining muscle strength and performance in older adults are associated with falls, fractures, and premature death.

OBJECTIVE

To determine whether supplementation with vitamin D3 or omega-3 fatty acids vs. placebo for 2 years improves physical performance measures.

DESIGN

VITamin D and OmegA-3 TriaL (VITAL) was a double-blinded, placebo-controlled randomized trial of supplemental vitamin D3 and/or omega-3 fatty acids vs. placebo in the prevention of cancer and cardiovascular disease in 25,871 U.S. adults. This ancillary study was completed in a New England sub-cohort that had in-person evaluations at baseline and 2-year follow-up.

SETTING

Center for Clinical Investigations in Boston.

PARTICIPANTS

1,054 participants (men ≥50 and women ≥55 years).

INTERVENTIONS

2x2 factorial design of supplemental vitamin D3 (cholecalciferol, 2000 IU/day) and/or marine omega-3 fatty acids (1 g/day).

MAIN OUTCOME MEASURES

2-year changes in physical performance measures of grip strength, walking speed, standing balance, repeated chair stands, and Timed-up and Go (TUG).

RESULTS

At 2 years, all randomized groups showed worsening walking speeds and TUG. There were no differences in changes in grip strength, walking speeds, Short Physical Performance Battery (composite of walking speed, balance, and chair stands), and TUG between the vitamin D3-treated and the placebo-treated groups and between the omega-3-treated and the placebo-treated groups. Effects overall did not vary by sex, age, body mass index, or baseline measures of total or free 25-hydroxyvitamin D (25[OH]D) or plasma n-3 index; TUG slightly worsened with vitamin D supplementation, compared to placebo, in participants with baseline total 25(OH)D levels above the median (p=0.01, p for interaction=0.04).

CONCLUSIONS

Neither supplemental vitamin D3 nor marine omega-3 fatty acids for 2 years improved physical performance in this generally healthy adult population.

Effectiveness of Vitamin D Supplements in Reducing the Risk of Falls among Older Adults: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

The role of vitamin D in reducing the risk of falls in older adults has not been clearly demonstrated. This study examined the effectiveness of vitamin D supplementation in reducing the risk of falls in older adults.

METHODS

Four databases (Cochrane Library, Embase, PubMed, and CINAHL) were searched without language restrictions or time limitations. These articles were comprehensively screened using EndNote version 20.1 software. A manual search of the reference lists of the identified studies was also performed. The analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The pooled evidence was analyzed using RevMan software version 5.4.

RESULTS

Seventeen studies met inclusion criteria among 550 potentially relevant studies. The pooled analysis of 38,598 older adults showed that vitamin D supplementation decreased the odds of having at least one fall by 1% (odds ratio [OR]=1.01; 95% confidence interval [CI], 0.92-1.11; p=0.86); however, the difference was not statistically significant. Of eight studies with 19,946 older adults, the pooled analysis showed a 12% (OR=1.12; 95% CI, 0.97-1.29; p=0.11) decrease in the odds of having at least one fracture among older adults; however, the difference was also not statistically significant. Pooled subgroup analysis showed that neither low (<2,000 IU/day) nor high (≥2,000 and <4,000 IU/day) doses of vitamin D supplementation had any significant effect on the incidence of falls and fractures.

CONCLUSION

Vitamin D supplementation had no beneficial effect in reducing fall and fracture incidence among older adults.

The effects of vitamin D on all-cause mortality in different diseases: an evidence-map and umbrella review of 116 randomized controlled trials

Purpose

To conduct a solid evidence by synthesizing meta-analyses and updated RCTs about the effects of vitamin D on all-cause mortality in different health conditions.

Methods

Data sources: Pubmed, Embase, Web of Science, the Cochrane Library, Google Scholar from inception until 25th April, 2022. Study selection: English-language, meta-analyses and updated RCTs assessing the relationships between vitamin D and all-cause mortality. Data synthesis: Information of study characteristics, mortality, supplementation were extracted, estimating with fixed-effects model. A Measurement Tool to Assess Systematic Reviews, Grading of Recommendations Assessment, Development and Evaluation, and funnel plot was used to assess risk of bias. Main outcomes: All-cause mortality, cancer mortality, cardiovascular disease mortality.

Results

In total of 27 meta-analyses and 19 updated RCTs were selected, with a total of 116 RCTs and 149, 865 participants. Evidence confirms that vitamin D reduces respiratory cancer mortality (RR, 0.56 [95%CI, 0.33 to 0.96]). All-cause mortality is decreased in patients with COVID-19 (RR, 0.54[95%CI, 0.33 to 0.88]) and liver diseases (RR, 0.64 [95%CI, 0.50 to 0.81]), especially in liver cirrhosis (RR, 0.63 [95%CI, 0.50 to 0.81]). As for other health conditions, such as the general health, chronic kidney disease, critical illness, cardiovascular diseases, musculoskeletal diseases, sepsis, type 2 diabetes, no significant association was found between vitamin D and all-cause mortality.

Conclusions

Vitamin D may reduce respiratory cancer mortality in respiratory cancer patients and all-cause mortality in COVID-19 and liver disorders' patients. No benefits showed in all-cause mortality after vitamin D intervention among other health conditions. The hypothesis of reduced mortality with vitamin D still requires exploration.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=252921, identifier: CRD42021252921.

Vitamin D Supplementation and Muscle Power, Strength and Physical Performance in Older Adults: A Randomized Controlled Trial

BACKGROUND

Low 25-hydroxyvitamin D (25[OH]D) concentrations (<30 ng/mL [<50 nmol/L]) have been associated with muscle weakness and impaired physical performance in observational studies. However, the effect of vitamin D supplementation on changes in muscle strength and physical performance in randomized controlled trials has been mixed.

OBJECTIVES

To determine the effect of daily vitamin D supplementation on leg power, strength, and physical performance in low-functioning older adults with 25(OH)D concentrations of 18 to <30 ng/mL.

METHODS

In this double-blind, randomized controlled trial, 136 low-functioning [Short Physical Performance Battery (SPPB) scores ≤10] adults aged 65-89 y with 25(OH)D concentrations of 18 to <30 ng/mL were randomly assigned to 2000 IU/d vitamin D3 or placebo for 12 mo. Lower-extremity leg power (primary outcome), leg and grip strength, SPPB, timed up and go (TUG), postural sway, and gait velocity and spatiotemporal parameters (secondary outcomes) were assessed at baseline, 4 and 12 mo. A subset (n = 37) also underwent a muscle biopsy at baseline and 4 mo and muscle fiber composition and contractile properties were assessed.

RESULTS

Participants' mean ± SD age and SPPB scores at baseline were 73.4 ± 6.3 y and 7.8 ± 1.8, respectively. Mean ± SD 25(OH)D concentrations at baseline and 12 mo were 19.4 ± 4.2 ng/mL and 28.6 ± 6.7 ng/mL in the vitamin D group and 19.9 ± 4.9 ng/mL and 20.2 ± 5.0 ng/mL in the placebo group for a mean ± SE difference of 9.1 ± 1.1 ng/mL (P < 0.0001). However, there were no differences in change in leg power, leg or grip strength, SPPB score, TUG, postural sway, or gait velocity and spatiotemporal parameters by intervention group over 12 mo or muscle fiber composition and contractile properties over 4 mo.

CONCLUSIONS

In low-functioning older adults with 25(OH)D concentrations of 18 to <30 ng/mL, randomization to 2000 IU/d vitamin D3 did not result in improvements in leg power, strength, or physical performance or muscle fiber composition and contractile properties. This trial was registered at clinicaltrials.gov as NCT02015611.

Inadequate Physical Activity Is Associated with Worse Physical Function in a Sample of COVID-19 Survivors with Post-Acute Symptoms

Background—Patients affected by Long COVID often report shorter times spent doing physical activity (PA) after COVID-19. The aim of the present study was to evaluate potential associations between PA levels and parameters of physical function in a cohort of COVID-19 survivors with post-acute symptoms, with a particular focus on individuals aged 65 and older. Materials and methods—PA levels before and after COVID-19 were assessed in a sample of patients that had recovered from COVID-19 and were admitted to a post-acute outpatient service at the Fondazione Policlinico Universitario Agostino Gemelli IRCCS (Rome, Italy). Participation in PA was operationalized as the engagement in leisure-time PA for at least 150 min per week in the last 3 months. Self-rated health and measures of physical performance and muscle strength were assessed. Results—Mean age of 1846 participants was 55.2 ± 14.4 years and 47% were women. Before COVID-19, inactivity was detected in 47% of the whole study population; only 28% maintained pre-COVID-19 PA engagement. Inactivity was more frequent in women. The stopping of physical activity was associated with increased BMI and CRP levels, lower vitamin D levels and a higher prevalence of post-COVID-19 fatigue, dyspnea, arthralgia, and myalgia. Active participants had higher handgrip strength and performed better on both the six-minute walking test (6MWT) and at the one-minute sit-to-stand test (1MSTST). In particular, at the 6MWT, participants 65 and older that were still active after COVID-19 walked 32 m more than sedentary peers. Moreover, the distance covered was 28 m more than those who were active only before COVID-19 (p = 0.05). Formerly active subjects performed similarly at the 6MWT to inactive participants. PA was associated with better self-rated health. Conclusions—Our findings reveal that inactivity is frequent in the post-acute COVID-19 phase. Stopping physical activity after COVID-19 results in measures of performance that are comparable to those who were never active. Relevant differences in the distance covered at the 6MWT were found between older active subjects and their sedentary peers.

The enigma of vitamin D supplementation in aging with obesity

INTRODUCTION

The American Geriatrics Society recommends a minimum daily supplement of 1,000 IU and underlines that a dosage lower than 600 IU do not prevent falls in elderly people.

EVIDENCE ACQUISITION

The author searched on PubMed, Medline, Embase, Scopus database the MeSH terms and keywords of "vitamin D," "(25(OH)D)," "elderly" and "obesity." The aim of this study was to support the rationale on the correct vitamin D supplementation in elderly people with obesity and overweight.

EVIDENCE SYNTHESIS

Ten studies were found suitable for consideration in writing this comprehensive evidence-based rapid review. The supplementation of vitamin D included 1500 elderly subjects with Body Mass Index (BMI) over 25 kg/m². This article proved that the daily vitamin D supplementation from 2000 to 4000 UI is highly recommended in elderly people with obesity because of: 1) sequestration of vitamin D by the adipose tissue; 2) increased catabolism of vita-in D in the adipose tissue; 3) decreased synthesis of serum 25 hydroxyvitamin D (25(OH)D) in the liver; 4) reduced sun-exposure; and 5) dosages equal at 1000 UI or lower that did not show any important effect on vitamin D deficiency and on related comorbidities in elderly people with obesity.

CONCLUSIONS

Gender, baseline levels of serum (25(OH)D) concentration, ethnicity and severity of BMI should be accounted for the correct supplementation of vitamin D in elderly population for the precision medicine goal.

Effect of vitamin D monotherapy on indices of sarcopenia in community-dwelling older adults: a systematic review and meta-analysis

BACKGROUND

Vitamin D supplementation is proposed as a potentially effective nutritional intervention to mitigate the risk of sarcopenia. The aim of this systematic review and meta-analysis was to investigate the impact of vitamin D supplementation monotherapy on indices of sarcopenia in community-dwelling older adults.

METHODS

A comprehensive search of the literature was conducted in PubMed, Web of Science, Scopus, and Cochrane Library. Eligible randomized controlled trials (RCTs) compared the effect of vitamin D supplementation (as monotherapy) with placebo on indices of sarcopenia in older (>50 years) adults. Using the random effects inverse-variance model, we calculated the mean difference (MD) in handgrip strength (HGS), short physical performance battery (SPPB), timed up and go (TUG), and appendicular lean mass (ALM) between groups. We also calculated the standardized mean difference (SMD) in general muscle strength and general physical performance (composite plot of all muscle strength and physical performance outcomes, respectively) between groups.

RESULTS

Ten RCTs were included in the meta-analysis. A significant decrease in SPPB scores was observed with vitamin D supplementation compared with placebo (MD: -0.23; 95% CI -0.40 to -0.06; I²  = 0%; P = 0.007). Vitamin D supplementation conferred no effect on HGS (MD: -0.07 kg; 95% CI -0.70 to 0.55; I²  = 51%, P = 0.82), TUG (MD: 0.07 s; 95% CI -0.08 to 0.22; I²  = 0%, P = 0.35), ALM (MD: 0.06 kg/m² ; 95% CI: -0.32 to 0.44; I²  = 73%, P = 0.77), general muscle strength (SMD: -0.01; 95% CI -0.17 to 0.15; I²  = 42%, P = 0.90), or general physical performance (SMD: -0.02; 95% CI -0.23 to 0.18; I²  = 71%, P = 0.83).

CONCLUSIONS

Vitamin D supplementation did not improve any sarcopenia indices in community-dwelling older adults and may compromise some aspects of physical performance. Future studies are warranted to investigate the impact of vitamin D supplementation on individual indices of SPPB, including mobility and balance, in older adults.

The Vitamin D/Vitamin D receptor (VDR) axis in muscle atrophy and sarcopenia

Muscle atrophy and sarcopenia (the term given to the age-related decline in muscle mass and function), influence an individuals risk of falls, frailty, functional decline, and, ultimately, impaired quality of life. Vitamin D deficiency (low serum levels of 25-hydroxyvitamin D (25(OH)D₃)) has been reported to impair muscle strength and increase risk of sarcopenia. The mechanisms that underpin the link between low 25(OH)D₃ and sarcopenia are yet to be fully understood but several lines of evidence have highlighted the importance of both genomic and non-genomic effects of active vitamin D (1,25-dihydroxyvitamin D (1,25(OH)₂D₃)) and its nuclear vitamin D receptor (VDR), in skeletal muscle functioning. Studies in vitro have demonstrated a key role for the vitamin D/VDR axis in regulating biological processes central to sarcopenic muscle atrophy, such as proteolysis, mitochondrial function, cellular senescence, and adiposity. The aim of this review is to provide a mechanistic overview of the proposed mechanisms for the vitamin D/VDR axis in sarcopenic muscle atrophy.

Effect of Vitamin D Supplementation on Risk of Fractures and Falls According to Dosage and Interval: A Meta-Analysis

BACKGROUND

Although recent studies comparing various dosages and intervals of vitamin D supplementation have been published, it is yet to be elucidated whether there is an appropriate dose or interval to provide benefit regarding fracture risk. We aimed to assess the published evidence available to date regarding the putative beneficial effects of vitamin D supplements on fractures and falls according to various dosages and intervals.

METHODS

We performed a meta-analysis of randomized controlled studies reporting associations between vitamin D supplementation and the risks of fractures and falls in PubMed, EMBASE, and Cochrane library. Studies with supplements of ergocalciferol or calcitriol, those with a number of event ≤10, or those with a follow-up duration of less than 6 months were also excluded.

RESULTS

Thirty-two studies were included in the final analysis. Vitamin D supplementation with daily dose of 800 to 1,000 mg was associated with lower risks of osteoporotic fracture and fall (pooled relative risk [RR], 0.87; 95% confidence interval [CI], 0.78 to 0.97 and RR, 0.91; 95% CI, 0.85 to 0.98), while studies with <800 or >1,000 mg/day did not. Also, among intervals, daily administration of vitamin D was associated with the reduced risk of falls, while intermittent dose was not. Also, patients with vitamin D deficiency showed a significant risk reduction of falls after vitamin D supplementation.

CONCLUSION

Daily vitamin D dose of 800 to 1,000 IU was the most probable way to reduce the fracture and fall risk. Further studies designed with various regimens and targeted vitamin D levels are required to elucidate the benefits of vitamin D supplements.

Role of circulating molecules in age-related cardiovascular and metabolic disorders

Studies analyzing heterochronic parabiosis mice models showed that molecules in the blood of young mice rejuvenate aged mice. Therefore, blood-based therapies have become one of the therapeutic approaches to be considered for age-related diseases. Blood includes numerous biologically active molecules such as proteins, metabolites, hormones, miRNAs, etc. and accumulating evidence indicates some of these change their concentration with chronological aging or age-related disorders. The level of some circulating molecules showed a negative or positive correlation with all-cause mortality, cardiovascular events, or metabolic disorders. Through analyses of clinical/translation/basic research, some molecules were focused on as therapeutic targets. One approach is the supplementation of circulating anti-aging molecules. Favorable results in preclinical studies let some molecules to be tested in humans. These showed beneficial or neutral results, and some were inconsistent. Studies with rodents and humans indicate circulating molecules can be recognized as biomarkers or therapeutic targets mediating their pro-aging or anti-aging effects. Characterization of these molecules with aging, testing their biological effects, and finding mimetics of young systemic milieu continue to be an interesting and important research topic to be explored.

Association Between Vitamin D Supplementation and Fall Prevention

BACKGROUND

Falls occur frequently among older individuals, leading to high morbidity and mortality. This study was to assess the efficacy of vitamin D in preventing older individuals from falling.

METHODS

We searched the PubMed, Cochrane Library, and EMBASE databases systematically using the keywords "vitamin D" and "fall" for randomized controlled trials (RCTs) comparing the effects of vitamin D with or without calcium supplements with those of a placebo or no treatment on fall incidence in adults older than 50 years. A meta-analysis was performed to calculate risk ratios (RRs), absolute risk differences (ARDs) and 95% CIs with random-effects models.

RESULTS

A total of 38 RCTs involving 61 350 participants fulfilled the inclusion criteria. Compared with placebo, high-dose vitamin D (≥ 700 IU) can prevent falls [RR, 0.87 (95% CI 0.79 to 0.96); ARD, -0.06 (95% CI, -0.10 to -0.02)]. Low-dose vitamin D (<700 IU) was not significantly associated with falls. Subgroup analysis showed that supplemental calcium, 25(OH) D concentration and frequency influenced the effect of vitamin D in preventing falls. Sensitivity analysis showed that vitamin D prevented falls, which was consistent with the primary analysis. In addition, the active form of vitamin D also prevented falls.

CONCLUSION

In this meta-analysis of RCTs, doses of 700 IU to 2000 IU of supplemental vitamin D per day were associated with a lower risk of falling among ambulatory and institutionalized older adults. However, this conclusion should be cautiously interpreted, given the small differences in outcomes.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42020179390.

Vitamin D supplementation reduces the risk of fall in the vitamin D deficient elderly: An updated meta-analysis

INTRODUCTION

Vitamin D supplementation has been widely recommended to prevent falls. However, considerable controversy exists regarding the association of such supplementation and fall risk. Previous meta-analyses yielded inconsistent results because of differences in the baseline of 25-hydroxyvitamin D [25(OH)D] and dose of vitamin D and use of vitamin D or in combination with calcium in different studies. Furthermore, some studies published recently were not included in the previous meta-analyses. Therefore, an updated and comprehensive meta-analysis is warranted.

METHODS

We systematically searched several literature databases including PubMed and the Embase from inception to September 2020. The protocol for this meta-analysis was registered with PROSPERO (CRD42021226380). Randomized clinical trials (RCTs) reporting the effect of vitamin D supplementation alone or with calcium on fall incidence were selected from studies. Qualitative and quantitative information was extracted; the random-effects model was conducted to pool the data for fall; statistical heterogeneity was assessed using the I² test and potential for publication bias was assessed qualitatively by a visual estimate of the funnel plot and quantitatively by calculation of the Begg's test and the Egger's test.

RESULTS

Of the citations retrieved, 31 eligible studies involving 57 867 participants met inclusion criteria, reporting 17 623 falls. A total of 21 RCTs of vitamin D alone and 10 RCTs of vitamin D plus calcium were included in the meta-analysis. The meta-analysis of 21 RCTs (51 984 participants) of vitamin D supplementation alone (daily or intermittent doses of 400-60 000 IU) did not show a reduced risk of falls (The risk ratio [RR] 1.00, 95% confidence intervals [CI] 0.95 to 1.05) compared to placebo or no treatment. Subgroup analyses showed that the baseline of serum 25(OH)D concentration less than 50 nmol/L resulted in a reduction of fall risk (RR 0.77, 95% CI 0.61 to 0.98). In contrast, the meta-analysis of 10 RCTs (5883 participants) of combined supplementation of vitamin D (daily doses of 700-1000 IU) and calcium (daily doses of 1000-1200 mg) showed a 12% reduction in the risk of fall (RR 0.88, 95% CI 0.80 to 0.97).

CONCLUSIONS

The combination of vitamin D and calcium have beneficial effects on prevention falls in old adults. Although vitamin D supplementation alone has no effect on fall risk in old adults with 25(OH)D levels higher than 50 nmol/L, vitamin D supplementation alone does have a benefit on prevention of falls in old adults with 25(OH)D levels lower than 50 nmol/L.

Vitamin D and Muscle Health: A Systematic Review and Meta-analysis of Randomized Placebo-Controlled Trials

The objective of this study was to investigate the effects of vitamin D supplementation versus placebo on muscle health. For this systematic review and trial-level meta-analysis of placebo-controlled trials, a systematic search of randomized controlled trials published until October 2020 was performed in Medline, Embase, and Google Scholar. We included studies in humans (except athletes) on supplementation with vitamin D2 or D3 versus placebo, regardless of administration form (daily, bolus, and duration) with or without calcium co-supplementation. The predefined endpoints were physical performance reported as timed up and go test (TUG; seconds), chair rising test (seconds), 6-minute walking distance (m), and Short Physical Performance Battery (SPPB; points). Furthermore, endpoints were maximum muscle strength (Newton) measured at handgrip, elbow flexion, elbow extension, knee flexion, and knee extension, as well as muscle (lean tissue) mass (kg). Falls were not included in the analysis. Cochrane Review Manager (version 5.4.1.) calculating mean difference (MD) using a random effect model was used. In total, 54 randomized controlled trials involving 8747 individuals were included. Vitamin D versus placebo was associated with a significantly longer time spent performing the TUG (MD 0.15 [95% confidence interval (CI) 0.03 to 0.26] seconds, N = 19 studies, I²  = 0%, n = 5223 participants) and a significant lower maximum knee flexion strength (MD -3.3 [-6.63 to -0.03] Newton, N = 12 studies, I²  = 0%, n = 765 participants). Total score in the SPPB showed a tendency toward worsening in response to vitamin D compared with placebo (MD -0.18 [-0.37 to 0.01] points, N = 8 studies, I²  = 0%, n = 856 participants). Other measures of muscle health did not show between-group differences. In subgroup analyses, including studies with low vitamin D levels, effects of vitamin D supplementation did not differ from placebo. Available evidence does not support a beneficial effect of vitamin D supplementation on muscle health. Vitamin D may have adverse effects on muscle health, which needs to be considered when recommending vitamin D supplementation. © 2021 American Society for Bone and Mineral Research (ASBMR).

Association between vitamin D deficiency and exercise capacity in patients with CKD, a cross-sectional analysis

BACKGROUND

Evidence is growing for a role of vitamin D in regulating skeletal muscle mass, strength and functional capacity. Given the role the kidneys play in activating total vitamin D, and the high prevalence of vitamin D deficiency in Chronic Kidney Disease (CKD), it is possible that deficiency contributes to the low levels of physical function and muscle mass in these patients.

METHODS

This is a secondary cross-sectional analysis of previously published interventional study, with in vitro follow up work. 34 CKD patients at stages G3b-5 (eGFR 25.5 ± 8.3 mL/min/1.73m2; age 61 ± 12 years) were recruited, with a sub-group (n = 20) also donating a muscle biopsy. Vitamin D and associated metabolites were analysed in plasma by liquid chromatography tandem-mass spectroscopy and correlated to a range of physiological tests of muscle size, function, exercise capacity and body composition. The effects of 1α,25(OH)2D3 supplementation on myogenesis and myotube size was investigated in primary skeletal muscle cells from vitamin D deficient donors.

RESULTS

In vivo, there was no association between total or active vitamin D and muscle size or strength, but a significant correlation with V̇O_2Peak was seen with total vitamin D (25OHD). in vitro, 1α,25(OH)₂D3 supplementation reduced IL-6 mRNA expression, but had no effect upon proliferation, differentiation or myotube diameter.

CONCLUSIONS

Vitamin D deficiency is not a prominent factor driving the loss of muscle mass in CKD, but may play a role in reduced exercise capacity.

The relationship between dietary patterns and grip strength in the general population: the TCLSIH cohort study

PURPOSE

Previous studies have shown that many nutrients play an essential role in maintaining skeletal muscle strength. Hand grip strength (HGS) is frequently used as an objective and reliable method to evaluate overall body muscle strength and physical function. Some studies have demonstrated that some specific single nutrients such as PUFA, fiber, vitamin C, fruits and vegetables are associated with muscle strength. However, few studies have explored the relationship between dietary patterns and HGS in the adult population. The aim of this study was to investigate how dietary patterns are related to HGS in a large-scale Chinese population.

METHODS

A cross-sectional study (n = 35,175) was performed in Tianjin, China. Adherence to dietary patterns was measured by a valid self-administered food frequency questionnaire with 81 food items. Principal-components analysis was used to derive three major dietary patterns: "sweet", "healthy" and "animal food". HGS was measured using a handheld digital dynamometer. Analysis of covariance and multiple logistic regression were employed to explore the relationship between dietary patterns and HGS.

RESULTS

After adjustment for potential confounders, the means (95% confidence interval) of HGS for increasing quartile of dietary patterns were as follows: "sweet", 0.50 (0.49-0.51), 0.50 (0.49-0.51), 0.50 (0.49-0.51), 0.50 (0.48-0.51) (P value = 0.07); "healthy" 0.50 (0.49-0.51), 0.50 (0.49-0.51), 0.50 (0.49-0.51), 0.50 (0.49-0.51) (P value < 0.0001); "animal food" 0.51(0.50-0.52), 0.50 (0.49-0.51), 0.50 (0.49-0.51), 0.49 (0.48-0.51) (P value < 0.0001), respectively.

CONCLUSIONS

The present study demonstrated a slight improvement between healthy dietary pattern and HGS across the quartiles. On the contrary, this study also showed higher adherence to the animal food dietary pattern (i.e., higher quartile) had lower grip strength. A long-term prospective study or randomized trials are required to clarify this association.

Vitamin D supplement on prevention of fall and fracture: A Meta-analysis of Randomized Controlled Trials

BACKGROUND

Vitamin D supplement is one of the current possible interventions to reduce fall and fracture. Despite having several studies on vitamin D supplement and fall and fracture reductions, the results are still inconclusive. We conducted a meta-analysis to examine the effect of vitamin D supplement in different forms and patient settings on fall and fracture.

METHODS

A systematic literature research was conducted in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials to identify randomized controlled trials (RCTs) to compare the effects of vitamin D supplements on fall and fracture outcomes. Random-effect models were used to compute the weighted mean difference for continuous variables and the risk ratio for binary variables.

RESULTS

Forty-seven RCTs with 58,424 participants were identified reporting on fall outcome. Twenty-four of 47 studies with 40,102 subjects also reported fracture outcome. Major populations were elderly women with age less than 80 years. Overall, vitamin D supplement demonstrated a significant effect on fall reduction, RR = 0.948 (95% CI 0.914-0.984; P = .004, I = 41.52). By subgroup analyses, only vitamin D with calcium supplement significantly reduce fall incidence, RR = 0.881 (95% CI 0.821-0.945; P < .001, I = 49.19). Vitamin D3 supplement decreased incidence of fall but this occurred only when vitamin D3 was supplemented with calcium. Regarding fracture outcome, vitamin D supplement failed to show fracture lowering benefit, RR = 0.949 (95% CI 0.846-1.064; P = .37, I = 37.92). Vitamin D along with calcium supplement could significantly lower fracture rates, RR = 0.859 (95% CI 0.741-0.996; P = .045, I = 25.48).

CONCLUSIONS

The use of vitamin D supplement, especially vitamin D3 could reduce incidence of fall. Only vitamin D with calcium supplement showed benefit in fracture reduction.

Optimizing Skeletal Muscle Anabolic Response to Resistance Training in Aging

Loss of muscle mass and strength with aging, also termed sarcopenia, results in a loss of mobility and independence. Exercise, particularly resistance training, has proven to be beneficial in counteracting the aging-associated loss of skeletal muscle mass and function. However, the anabolic response to exercise in old age is not as robust, with blunted improvements in muscle size, strength, and function in comparison to younger individuals. This review provides an overview of several physiological changes which may contribute to age-related loss of muscle mass and decreased anabolism in response to resistance training in the elderly. Additionally, the following supplemental therapies with potential to synergize with resistance training to increase muscle mass are discussed: nutrition, creatine, anti-inflammatory drugs, testosterone, and growth hormone (GH). Although these interventions hold some promise, further research is necessary to optimize the response to exercise in elderly patients.

Four months vitamin D supplementation to vitamin D insufficient individuals does not improve muscular strength: A randomized controlled trial

Main objective

The inconsistent results on the effects of vitamin D on muscle strength reported by intervention trials may partly be explained by inclusion of vitamin D sufficient individuals. The main objective was to study whether vitamin D supplementation will improve muscle strength in men and women with low serum vitamin D status, as measured by 25-hydroxyvitamin D (25(OH)D) at baseline.

Methods

417 men and women aged 40–80 years were included and randomized to receive a loading dose of 100 000 IU (2500 ug) vitamin D₃ followed by 20 000 IU (500 ug)/week, or placebo. Muscle strength was tested by dynamometers at baseline and after four months.

Results

Serum 25(OH)D levels increased from 32.6±11.1 nmol/l to 88.8±19.4 nmol/l (p<0.01) in the vitamin D group, while remaining low in the placebo group (baseline and final levels at 35.1±13.6 nmol/l and 30.7 ±9.7 nmol/l respectively). Muscle strength (hip flexion, biceps flexion, pectorals and handgrip strength) did not change in any of the groups. The results were the same in analyses stratified on sex, 25(OH)D above/below 25 nmol/L (10 ng/ml); smoking status; and BMI above/below 27 kg/m².

Conclusion

These data does not support vitamin D supplementation for improving muscle strength.

Vitamin D Deficiency and Sarcopenia in Older Persons

Vitamin D deficiency is a common health problem worldwide, in particular among older people. Vitamin D regulates and modulates the physiology and function of multiple human systems, including the skeletal muscle. The effect of vitamin D on the muscle has been widely investigated, suggesting that this hormone can stimulate the proliferation and differentiation of skeletal muscle fibers, maintaining and improving muscle strength and physical performance. Older persons have a higher prevalence of low Vitamin D levels as a consequence of low dietary intake and reduced ultraviolet irradiation of the skin. Therefore, older people with vitamin D deficiency might be at risk of sarcopenia, a geriatric syndrome characterized by the progressive loss of skeletal muscle mass and strength often complicated by adverse events, such as falls, disability hospitalization and death. Several randomized clinical trials have been conducted to investigate the effect of oral vitamin D supplementation in older patients to prevent or treat sarcopenia, but results are still controversial. In this narrative review we summarize the biological, clinical and epidemiological evidence supporting the hypothesis of a causal association between Vitamin D deficiency and an increased risk of sarcopenia in older people.

Vitamin D supplementation for the prevention of depression and poor physical function in older persons: the D-Vitaal study, a randomized clinical trial

BACKGROUND

Depressive symptoms and impaired physical functioning are prevalent among older adults. Supplementation with vitamin D might improve both conditions, particularly in persons with low vitamin D status.

OBJECTIVE

The D-Vitaal study primarily aimed to investigate the effect of vitamin D supplementation on depressive symptoms, functional limitations, and physical performance in a high-risk older population with low vitamin D status. Secondary aims included examining the effect of vitamin D supplementation on anxiety symptoms, cognitive functioning, mobility, handgrip strength, and health-related quality of life.

METHODS

This study was a randomized placebo-controlled trial with 155 participants aged 60-80 y who had clinically relevant depressive symptoms, ≥1 functional limitations, and serum 25-hydroxyvitamin D [25(OH)D] concentrations of 15-50/70 nmol/L (depending on season). Participants received 1200 IU/d vitamin D3 (n = 77) or placebo tablets (n = 78) for 12 mo. Serum 25(OH)D was measured at baseline and 6 mo; outcomes were assessed at baseline, 6 mo, and 12 mo. Linear mixed-models analyses were conducted to assess the effect of the intervention.

RESULTS

The supplementation increased serum 25(OH)D concentrations in the intervention group to a mean ± SD of 85 ± 16 nmol/L compared with 43 ± 18 nmol/L in the placebo group after 6 mo (P < 0.001). No relevant differences between the treatment groups were observed regarding depressive symptoms, functional limitations, physical performance, or any of the secondary outcomes.

CONCLUSIONS

Supplementation with 1200 IU/d vitamin D for 12 mo had no effect on depressive symptoms and physical functioning in older persons with relatively low vitamin D status, clinically relevant depressive symptoms, and poor physical functioning. This trial is registered with the Netherlands Trial Register (www.trialregister.nl) under NTR3845.

Association between vitamin D supplementation and mortality: systematic review and meta-analysis

OBJECTIVE

To investigate whether vitamin D supplementation is associated with lower mortality in adults.

DESIGN

Systematic review and meta-analysis of randomised controlled trials.

DATA SOURCES

Medline, Embase, and the Cochrane Central Register from their inception to 26 December 2018.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials comparing vitamin D supplementation with a placebo or no treatment for mortality were included. Independent data extraction was conducted and study quality assessed. A meta-analysis was carried out by using fixed effects and random effects models to calculate risk ratio of death in the group receiving vitamin D supplementation and the control group.

MAIN OUTCOME MEASURES

All cause mortality.

RESULTS

52 trials with a total of 75 454 participants were identified. Vitamin D supplementation was not associated with all cause mortality (risk ratio 0.98, 95% confidence interval 0.95 to 1.02, I²=0%), cardiovascular mortality (0.98, 0.88 to 1.08, 0%), or non-cancer, non-cardiovascular mortality (1.05, 0.93 to 1.18, 0%). Vitamin D supplementation statistically significantly reduced the risk of cancer death (0.84, 0.74 to 0.95, 0%). In subgroup analyses, all cause mortality was significantly lower in trials with vitamin D₃ supplementation than in trials with vitamin D₂ supplementation (P for interaction=0.04); neither vitamin D₃ nor vitamin D₂ was associated with a statistically significant reduction in all cause mortality.

CONCLUSIONS

Vitamin D supplementation alone was not associated with all cause mortality in adults compared with placebo or no treatment. Vitamin D supplementation reduced the risk of cancer death by 16%. Additional large clinical studies are needed to determine whether vitamin D₃ supplementation is associated with lower all cause mortality.

STUDY REGISTRATION

PROSPERO registration number CRD42018117823.

Effect of nutritional supplementations on physical performance and muscle strength parameters in older people: A systematic review and meta-analysis

Malnutrition plays a role in the development of poor physical performance, frailty and sarcopenia. The use of nutritional supplementations for improving physical performance and muscle strength parameters in older people is unclear. We therefore aimed to summarize the effect of nutritional supplementations compared to placebo on physical performance (i.e. tests more investigating physical function, utilising aerobic capacity & muscle power) and muscle strength (i.e. tests depending on muscle power) outcomes in older people in randomized controlled trials (RCTs). A literature search in major databases was undertaken until the 01st September 2018. Eligible studies were RCTs investigating the effect of nutritional supplementations vs. placebo in older people (people having an age >60 years). Standardized mean differences (SMD) and 95% confidence intervals (CIs) were used through a random effect model. Over 4007 potentially eligible articles, 32 RCTs for a total of 4137 older participants (2097 treated and 2040 placebo) (mean age: 76.3 years; 65% females) were included. Compared to placebo, multi-nutrient supplementations significantly improved chair rise time (n = 3; SMD=-0.90; 95%CI: -1.46 to -0.33; I² = 87%). Multi-nutrients significantly improved handgrip strength when compared to placebo (n = 6; 780 participants; SMD = 0.41; 95%CI: 0.06 to 0.76; I² = 79%), as did nutritional supplementations including protein (n = 7; 535 participants; SMD = 0.24; 95%CI: 0.07 to 0.41; I² = 16%).Nutritional supplementations also led to a significant improvement in chair rise time and in handgrip strength in participants affected by frailty/sarcopenia and in those affected by medical conditions. In conclusion, nutritional supplementation can improve a number of physical performance outcomes in older people, particularly when they include multi-nutrients and in people already affected by specific medical conditions, or by frailty/sarcopenia.

Local In Vivo Measures of Muscle Lipid and Oxygen Consumption Change in Response to Combined Vitamin D Repletion and Aerobic Training in Older Adults

Intramyocellular (IMCL), extramyocellular lipid (EMCL), and vitamin D deficiency are associated with muscle metabolic dysfunction. This study compared the change in [IMCL]:[EMCL] following the combined treatment of vitamin D and aerobic training (DAT) compared with vitamin D (D), aerobic training (AT), and control (CTL). Male and female subjects aged 60–80 years with a BMI ranging from 18.5–34.9 and vitamin D status of ≤32 ng/mL (25(OH)D) were recruited to randomized, prospective clinical trial double-blinded for supplement with a 2 × 2 factorial design. Cholecalciferol (Vitamin D₃) (10,000 IU × 5 days/week) or placebo was provided for 13 weeks and treadmill aerobic training during week 13. Gastrocnemius IMCL and EMCL were measured with magnetic resonance spectroscopy (MRS) and MRI. Hybrid near-infrared diffuse correlation spectroscopy measured hemodynamics. Group differences in IMCL were observed when controlling for baseline IMCL (p = 0.049). DAT was the only group to reduce IMCL from baseline, while a mean increase was observed in all other groups combined (p = 0.008). IMCL reduction and the corresponding increase in rVO₂ at study end (p = 0.011) were unique to DAT. Vitamin D, when combined with exercise, may potentiate the metabolic benefits of exercise by reducing IMCL and increasing tissue-level VO₂ in healthy, older adults.

The effect of vitamin D supplementation on lower-extremity power and function in older adults: a randomized controlled trial

Background

The effect of vitamin D supplementation on muscle function in older adults has been tested in randomized trials with mixed results, which may be due to differences in the study participant characteristics, including baseline vitamin D status. The results of 2 meta-analyses of randomized trials suggested a beneficial effect of vitamin D supplementation on muscle function in older adults with low baseline serum 25-hydroxyvitamin D [25(OH)D].

Objectives

We aimed to test the effect of 12 mo of vitamin D supplementation on lower-extremity power and function in older community-dwelling adults screened for low serum 25(OH)D.

Methods

This was a single-center, double-blind, randomized, placebo-controlled trial that included 100 community-dwelling men and women ≥60 y old who had serum 25(OH)D ≤20 ng/mL at screening and a mean ± SD serum 25(OH)D of 20.2 ± 6.7 ng/mL at baseline. Participants were randomly assigned to 800 IU vitamin D3/d (intervention) or placebo. Those in the intervention group whose serum 25(OH)D was <28 ng/mL after 4 mo were given an additional 800 IU vitamin D3/d, whereas all other participants received placebo as an additional pill.

Results

After 12 mo, the mean ± SD serum 25(OH)D was 32.5 ± 5.1 ng/mL in the intervention group and 19.8 ± 7.3 ng/mL in the control group (treatment × time P < 0.001). The change in leg press power, function, and strength did not differ between the 2 groups over 12 mo (all treatment × time P ≥ 0.60), nor did the change in lean mass (treatment × time P ≥ 0.89).

Conclusion

Increasing serum 25(OH)D to >32 ng/mL (on average) over 12 mo did not affect lower-extremity power, strength, or lean mass in older community-dwelling adults. This trial was registered at clinicaltrials.gov as NCT02293187.

Effects of vitamin D supplementation on musculoskeletal health: a systematic review, meta-analysis, and trial sequential analysis

BACKGROUND

The effects of vitamin D on fractures, falls, and bone mineral density are uncertain, particularly for high vitamin D doses. We aimed to determine the effect of vitamin D supplementation on fractures, falls, and bone density.

METHODS

In this systematic review, random-effects meta-analysis, and trial sequential analysis, we used findings from literature searches in previously published meta-analyses. We updated these findings by searching PubMed, Embase, and Cochrane Central on Sept 14, 2017, and Feb 26, 2018, using the search term "vitamin D" and additional keywords, without any language restrictions. We assessed randomised controlled trials of adults (>18 years) that compared vitamin D with untreated controls, placebo, or lower-dose vitamin D supplements. Trials with multiple interventions (eg, co-administered calcium and vitamin D) were eligible if the study groups differed only by use of vitamin D. We excluded trials of hydroxylated vitamin D analogues. Eligible studies included outcome data for total or hip fractures, falls, or bone mineral density measured at the lumbar spine, total hip, femoral neck, total body, or forearm. We extracted data about participant characteristics, study design, interventions, outcomes, funding sources, and conflicts of interest. The co-primary endpoints were participants with at least one fracture, at least one hip fracture, or at least one fall; we compared data for fractures and falls using relative risks with an intention-to-treat analysis using all available data. The secondary endpoints were the percentage change in bone mineral density from baseline at lumbar spine, total hip, femoral neck, total body, and forearm.

FINDINGS

We identified 81 randomised controlled trials (n=53 537 participants) that reported fracture (n=42), falls (n=37), or bone mineral density (n=41). In pooled analyses, vitamin D had no effect on total fracture (36 trials; n=44 790, relative risk 1·00, 95% CI 0·93-1·07), hip fracture (20 trials; n=36 655, 1·11, 0·97-1·26), or falls (37 trials; n=34 144, 0·97, 0·93-1·02). Results were similar in randomised controlled trials of high-dose versus low-dose vitamin D and in subgroup analyses of randomised controlled trials using doses greater than 800 IU per day. In pooled analyses, there were no clinically relevant between-group differences in bone mineral density at any site (range -0·16% to 0·76% over 1-5 years). For total fracture and falls, the effect estimate lay within the futility boundary for relative risks of 15%, 10%, 7·5%, and 5% (total fracture only), suggesting that vitamin D supplementation does not reduce fractures or falls by these amounts. For hip fracture, at a 15% relative risk, the effect estimate lay between the futility boundary and the inferior boundary, meaning there is reliable evidence that vitamin D supplementation does not reduce hip fractures by this amount, but uncertainty remains as to whether it might increase hip fractures. The effect estimate lay within the futility boundary at thresholds of 0·5% for total hip, forearm, and total body bone mineral density, and 1·0% for lumbar spine and femoral neck, providing reliable evidence that vitamin D does not alter these outcomes by these amounts.

INTERPRETATION

Our findings suggest that vitamin D supplementation does not prevent fractures or falls, or have clinically meaningful effects on bone mineral density. There were no differences between the effects of higher and lower doses of vitamin D. There is little justification to use vitamin D supplements to maintain or improve musculoskeletal health. This conclusion should be reflected in clinical guidelines.

FUNDING

Health Research Council of New Zealand.

The impact of treatment for iron deficiency and iron deficiency anemia on nutritional status, physical performance, and cognitive function in geriatric patients

OBJECTIVE

Iron deficiency in older people is common and affects physical and cognitive performance. The effects of iron deficiency on nutrition and cognitive status are well established. However, there are few studies demonstrating the impact of iron deficiency treatment on functional and cognitive outcomes in the geriatric population. The aim of this study was to determine whether iron replacement treatment was associated with an improvement in the nutritional, cognitive, and functional status of older patients with iron deficiency (ID) and iron deficiency anemia (IDA).

METHODS

Geriatric patients with iron deficiency and iron deficiency anemia presenting to the geriatric clinic were included in the study. Comprehensive geriatric assessment (CGA) and blood samples to investigate iron deficiency were performed at baseline and 6 month later. 81 patients were included in the study and were evaluated at follow-up in the 6th month. The CGA included the following tests: the Katz Index of Independence in Activities of Daily Living Scale (Katz ADL), the Lawton-Brody Instrumental Activities of Daily Living Scale (IADL), the Mini-Mental State Examination (MMSE), and the Mini Nutritional Assessment Short-Form (MNA-SF), as well as the assessments of hand grip strength and walking speed.

RESULTS

Of the 81 participating patients, 69.1% were women and 30.9% were men. The mean age was 76.8 ± 7.28 years. Follow-up after iron supplementation treatment was performed with a mean of 6.23 ± 1.58 months. Improvements occurred in the following geriatric and laboratory assessments: Lawton-Brody (IADL), MNA-SF, MMSE, hand grip strength, and walking speed evaluations and the levels of hemoglobin, iron, total iron-binding capacity, transferrin saturation, and ferritin.

CONCLUSIONS

It was shown that iron replacement treatment has a positive impact on functional and cognitive status and nutritional parameters in older patients with ID and IDA.

Design Features of Randomized Clinical Trials of Vitamin D and Falls: A Systematic Review

Recent guidelines have advocated against the use of vitamin D supplementation as a means to prevent falls in older adults. However, meta-analyses of the available trials have reached divergent conclusions, and the key design features of these trials have not been well characterized. We conducted a systematic review of 30 randomized trials that reported the effects of vitamin D supplements on falls. Trials were identified by reviewing references of published meta-analyses and updated with a systematic PubMed search. We assessed three key design features: (1) recruitment of participants with vitamin D deficiency or insufficiency; (2) provision of daily oral vitamin D supplementation; and (3) utilization of highly sensitive at-event falls ascertainment. The trials enrolled a median of 337 (IQR: 170-1864) participants. Four (13.3%) trials restricted enrollment to those who were at least vitamin D insufficient, 18 (60.0%) included at least one arm providing daily supplementation, and 16 (53.3%) used at-event reporting. There was substantial heterogeneity between trials, and no single trial incorporated all three key design features. Rather than concluding that vitamin D is ineffective as a means to prevent falls, these findings suggest that existing trial evidence is insufficient to guide recommendations on the use of vitamin D supplements to prevent falls.

Vitamin D and osteosarcopenia: an update from epidemiological studies

PURPOSE OF REVIEW

The review summarizes recent epidemiological studies that examined the relationship between osteoporosis and sarcopenia to assess the impact of vitamin D status or supplementation on health outcomes related to these two medical conditions.

RECENT FINDINGS

Osteoporosis and sarcopenia are major public health problems, but whether these two diseases should be considered alone or combined into a single condition is not clear. No consensual definition of osteosarcopenia is largely accepted. Most observational studies demonstrate some relationship between muscle and bone health. Vitamin D status is generally lower in study participants with bone or muscle wasting. Studies on the effects of vitamin D supplementation on muscle or bone health have provided conflicting results, likely because of the heterogeneity between studies. However, the most positive results were observed in study participants with low vitamin D status and in studies that avoided massive boluses of vitamin D.

SUMMARY

More observational and interventional studies are needed to confirm the exact role of vitamin D in the pathophysiology and treatment of osteosarcopenia.