Vitamin D is related to handgrip strength in adult men aged 50 years and over: A population study from the TCLSIH cohort study

Sex-dependent association of serum vitamin D with muscle strength in older adults: NHANES 2001-2002

BACKGROUND

Although several studies have suggested a potential positive association between serum vitamin D levels and muscle strength in older adults, it remains unclear whether this relationship is sex-dependent.

AIM

To evaluate the association between serum 25 hydroxyvitamin D [25(OH)D] levels and muscle strength in older adults and to assess whether this association is dependent on sex.

METHODS

This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2001 and 2002. A total of 1173 individuals aged 50-85 years (630 men and 543 women) were included in the analysis. The peak isokinetic force of the knee extensor was assessed using a kinetic communicator isokinetic dynamometer. Serum 25(OH)D levels were measured using the standardized liquid chromatography-tandem mass spectrometry method. Linear regression analyses were conducted to estimate coefficients and 95% confidence intervals for muscle strength across tertiles of serum vitamin D levels, adjusting for potential confounders.

RESULTS

Tertiles of serum vitamin D were positively associated with muscle strength in older men (p-trend = 0.007), whereas no association was observed in older women (p-trend = 0.140) or in the total sample (men and women together; p-trend = 0.139).

CONCLUSION

Serum vitamin D levels were positively associated with muscle strength specifically in older men, whereas no association was observed in older women. These results suggest that the relationship between vitamin D and strength may be sex-dependent.

Vitamin D and Sarcopenia in the Senior People: A Review of Mechanisms and Comprehensive Prevention and Treatment Strategies

This article reviews the mechanisms and prevention strategies associated with vitamin D and sarcopenia in older adults. As a geriatric syndrome, sarcopenia is defined by a notable decline in skeletal muscle mass and strength, which increases the risk of adverse health outcomes such as falls and fractures. Vitamin D, an essential fat-soluble vitamin, is pivotal in skeletal muscle health. It affects muscle function through various mechanisms, including regulating calcium and phosphorus metabolism, promoting muscle protein synthesis, and modulation of muscle cell proliferation and differentiation. A deficiency in vitamin D has been identified as a significant risk factor for the development of sarcopenia in older adults. Many studies have demonstrated that low serum vitamin D levels are significantly associated with an increased risk of sarcopenia. While there is inconsistency in the findings, most studies support the importance of vitamin D in maintaining skeletal muscle health. Vitamin D influences the onset and progression of sarcopenia through various pathways, including the promotion of muscle protein synthesis, the regulation of mitochondrial function, and the modulation of immune and inflammatory responses. Regarding the prevention and treatment of sarcopenia, a combination of nutritional, exercise, and pharmacological interventions is recommended. Further research should be conducted to elucidate the molecular mechanism of vitamin D in sarcopenia, to study genes related to sarcopenia, to perform large-scale clinical trials, to investigate special populations, and to examine the combined application of vitamin D with other nutrients or drugs. A comprehensive investigation of the interconnection between vitamin D and sarcopenia will furnish a novel scientific foundation and productive strategies for preventing and treating sarcopenia. This, in turn, will enhance the senior people's quality of life and health.

Analysis of Grip Strength and Its Explanatory Factors in Older Patients with Gastrointestinal Tumours

Aim

To investigate the grip strength of older patients with gastrointestinal tumours and analyse its explanatory factors.

Methods

A total of 170 older patients with gastrointestinal tumours admitted to the Gastrointestinal Surgery Department of a Grade-III hospital in the Zhejiang province from January 2022 to December 2022 were selected as the investigation participants. Among them, there were 102 cases of gastric cancer (60.0%) and 68 cases of colon cancer (40.0%). There were 110 male patients (64.7%) and 60 female patients (35.3%), with patient ages ranging between 64 and 82 years old. A cross-sectional survey was conducted using a general data questionnaire, grip apparatus and the Nutritional Risk Screening 2002 (NRS-2002) score. Multiple linear regression was used to analyse the explanatory factors on the grip strength of older patients with gastrointestinal tumours.

Results

The grip strength of older patients with gastrointestinal tumours was 25.3±5.3 kg. Multiple linear regression analysis showed that gender, age, disease, body mass index (BMI), albumin concentration and the NRS-2002 score were the main explanatory factors on grip strength (P<0.05).

Conclusion

Grip strength was lower in older patients with gastrointestinal tumours and was lower in females, those aged ≥70 years, patients with colorectal cancer, individuals with a BMI of <18.5, those with an albumin concentration of <35g/l and those with an NRS2002 score of ≥3. Clinical staff should dynamically evaluate the level of grip strength in patients with gastrointestinal tumors and develop individualized interventions based on the related explanatory factors.

The Relationship Between Sarcopenia And Proteinuria, What Do We Know?

Sarcopenia is one of the most common geriatric syndromes in the elderly. It is defined as a decrease in muscle mass and function, and it can lead to physical disability, falls, poor quality of life, impaired immune system, and death. It is known that, the frequency of sarcopenia increases in the kidney patient population compared to healthy individuals. Although it is known that kidney disease can lead to sarcopenia; our knowledge of whether sarcopenia causes kidney disease is limited. Prior studies have suggested that protein energy wasting may be a risk of de novo CKD. Proteinuria is an important manifestation of kidney disease and there is a relationship between sarcopenia and proteinuria in diabetes, geriatric population, kidney transplant, and nephrotic syndrome. Does proteinuria cause sarcopenia or vice versa? Are they both the results of common mechanisms? This issue is not clearly known. In this review, we examined the relationship between sarcopenia and proteinuria in the light of other studies.

A Machine-Learning Approach to Target Clinical and Biological Features Associated with Sarcopenia: Findings from Northern and Southern Italian Aging Populations

Epidemiological and public health resonance of sarcopenia in late life requires further research to identify better clinical markers useful for seeking proper care strategies in preventive medicine settings. Using a machine-learning approach, a search for clinical and fluid markers most associated with sarcopenia was carried out across older populations from northern and southern Italy. A dataset of adults >65 years of age (n = 1971) made up of clinical records and fluid markers from either a clinical-based subset from northern Italy (Pavia) and a population-based subset from southern Italy (Apulia) was employed (n = 1312 and n = 659, respectively). Body composition data obtained by dual-energy X-ray absorptiometry (DXA) were used for the diagnosis of sarcopenia, given by the presence of either low muscle mass (i.e., an SMI < 7.0 kg/m² for males or <5.5 kg/m² for females) and of low muscle strength (i.e., an HGS < 27 kg for males or <16 kg for females) or low physical performance (i.e., an SPPB ≤ 8), according to the EWGSOP2 panel guidelines. A machine-learning feature-selection approach, the random forest (RF), was used to identify the most predictive features of sarcopenia in the whole dataset, considering every possible interaction among variables and taking into account nonlinear relationships that classical models could not evaluate. Then, a logistic regression was performed for comparative purposes. Leading variables of association to sarcopenia overlapped in the two population subsets and included SMI, HGS, FFM of legs and arms, and sex. Using parametric and nonparametric whole-sample analysis to investigate the clinical variables and biological markers most associated with sarcopenia, we found that albumin, CRP, folate, and age ranked high according to RF selection, while sex, folate, and vitamin D were the most relevant according to logistics. Albumin, CRP, vitamin D, and serum folate should not be neglected in screening for sarcopenia in the aging population. Better preventive medicine settings in geriatrics are urgently needed to lessen the impact of sarcopenia on the general health, quality of life, and medical care delivery of the aging population.

25-hydroxyvitamin D level is associated with greater grip strength across adult life span: a population-based cohort study

OBJECTIVE

Maintaining muscle function throughout life is critical for healthy ageing. Although in vitro studies consistently indicate beneficial effects of 25-hydroxyvitamin D (25-OHD) on muscle function, findings from population-based studies remain inconclusive. We therefore aimed to examine the association between 25-OHD concentration and handgrip strength across a wide age range and assess potential modifying effects of age, sex and season.

METHODS

We analysed cross-sectional baseline data of 2576 eligible participants out of the first 3000 participants (recruited from March 2016 to March 2019) of the Rhineland Study, a community-based cohort study in Bonn, Germany. Multivariate linear regression models were used to assess the relation between 25-OHD levels and grip strength while adjusting for age, sex, education, smoking, season, body mass index, physical activity levels, osteoporosis and vitamin D supplementation.

RESULTS

Compared to participants with deficient 25-OHD levels (<30 nmol/L), grip strength was higher in those with inadequate (30 to <50 nmol/L) and adequate (≥50 to ≤125 nmol/L) levels (ßinadequate = 1.222, 95% CI: 0.377; 2.067, P = 0.005; ßadequate = 1.228, 95% CI: 0.437; 2.019, P = 0.002). Modelling on a continuous scale revealed grip strength to increase with higher 25-OHD levels up to ~100 nmol/L, after which the direction reversed (ßlinear = 0.505, 95% CI: 0.179; 0.830, P = 0.002; ßquadratic = -0.153, 95% CI: -0.269; -0.038, P = 0.009). Older adults showed weaker effects of 25-OHD levels on grip strength than younger adults (ß25OHDxAge = -0.309, 95% CI: -0.594; -0.024, P = 0.033).

CONCLUSIONS

Our findings highlight the importance of sufficient 25-OHD levels for optimal muscle function across the adult life span. However, vitamin D supplementation should be closely monitored to avoid detrimental effects.

Severe deficiency of vitamin D has no negative effect on physical performance during military training

BACKGROUND

Decreased physical fitness and inferior physical performance are potentially life-threatening risk factors in a combat situation. To examine the effect of vitamin D on physical performance, a prospective study of young men conscripts in the Estonian Army was designed. The hypothesis of the study was that severe deficiency of vitamin D has a negative effect on physical performance.

METHODS

All conscripts (N.=410) entering 10-month military service in July 2015 at the Kuperjanov Battalion were asked to participate. Initially, a total of 98 conscripts volunteered to participate. A prospective longitudinal study with a 10-month follow-up period was performed. The Army Physical Fitness Test (APFT) was performed three times, and hand grip strength, and blood serum values of 25(OH)D, parathyroid hormone (PTH) and calcium (Ca) were measured four times.

RESULTS

A significant decrease in the levels of 25(OH)D compared with baseline values were found, with a lowest mean value of 31.9 nmol/L in March 2016 (P<0.001). No significant differences were found in serum Ca levels. In March 2016, PTH was significantly higher in the severe deficiency group (<25 nmol/L of 25(OH)D) (P=0.02). No significant differences were found in terms of the APFT or hand grip strength between conscripts with severe deficiency of 25(OH)D or values >25 nmol/L. The main finding of the present study was that severe 25(OH)D deficiency was common among male conscripts during the winter season but had no negative effect on physical performance in terms of the APFT test and hand grip strength test.

CONCLUSIONS

Severe vitamin D deficiency during the winter season is common but has no negative effect on physical performance in young, physically active men in military service.

Seven-month wintertime supplementation of 1200 IU vitamin D has no effect on hand grip strength in young, physically active males: A randomized, controlled study

Background

Study Design

Methods

Results

Conclusion

Relationship between Lifestyle and Residence Area with 25(OH)D Levels in Older Adults

The aim of this study was to investigate whether the habitat of older adults living in the urban and rural areas is a contributing factor to altered serum 25(OH)D levels. An analytical, cross-sectional research with a quantitative approach was conducted in the upper backwoods of Paraíba with older adults registered at the Reference Center for Social Assistance (CRAS), addressing residents of both rural area (n = 41) and urban area (n = 43) who were randomly chosen to participate in the study. Data collection took place between January and February 2020. Higher rates of handgrip strength were observed in rural older adults (29.22 ± 8.92 Kgf) with serum 25(OH)D levels in the range of 30 to 40 ng/mL when compared to older adults with concentrations below 30 ng/mL (21.82 ± 5.00 Kgf) and above 40 ng/mL (23.47 ± 6.88 Kgf). Older people living in the urban area, with 25(OH)D levels above 40 ng/mL, presented a lower muscle power index when compared to individuals with vitamin levels from 21 to 29 ng/mL (17.40 ± 6.34 s; 15.33 ± 2.00 s). The urbanization associated with 25(OH)D levels can cause changes in skeletal and respiratory muscle strength, because the habitat associated with 25(OH)D levels affects the parameters of muscle strength of the upper limbs for older adults living in a rural area and the muscle strength of the lower limbs for those living in an urban area.

Serum vitamin D status and circulating irisin levels in older adults with sarcopenia

Background

Emerging evidence suggests sarcopenia, which is involved in the serum vitamin D deficiency and development of abnormal muscle metabolism, is predominately centered in the general older population. In the present study, we aimed to explore the relationship between the level of serum vitamin D and irisin concentrations in the older adults with sarcopenia.

Methods

A cross-sectional study was conducted which included 422 sarcopenia participants (146 males and 276 females). Sarcopenia was assessed according to the recommended diagnostic criteria of the Asia Working Group for Sarcopenia (AWGS). The levels of serum 25-hydroxyvitamin D (25(OH)D), 25-hydroxyvitamin D₂ (25(OH)D₂) and 25-hydroxyvitamin D₃ (25(OH)D₃) were determined by LC-MS/MS. Irisin levels were measured by enzyme-linked immunosorbent assay (ELISA). The relationship between serum concentration of vitamin D and irisin were determined using multiple linear regression analysis.

Results

After adjustment for potential confounding factors, a significant and positive relationship between changes in irisin across 25(OH)D, and 25(OH)D₃ was observed (standard regression coefficients of 0.150 and 0.151, respectively, P < 0.05). However, no significant relationship was observed between serum vitamin D concentrations and irisin levels in males.

Conclusions

This study demonstrated that a higher level of serum vitamin D is independently related to the increment of irisin in sarcopenia females, not in males. These investigations need to be verified in other large-scale prospective studies.

Are Serum 25-Hydroxyvitamin D Deficiency and Insufficiency Risk Factors for the Incidence of Dynapenia?

Epidemiological evidence showing the association between low 25(OH)D and age-related reduction in neuromuscular strength (dynapenia) is a paucity and controversial and, to date, the effect of osteoporosis and vitamin D supplementation on these associations has not been measured. Thus, we analyze whether serum 25(OH)D deficiency and insufficiency are risk factors for the incidence of dynapenia in individuals aged 50 or older and whether osteoporosis or vitamin D supplementation modify these associations. For that, 3205 participants of the ELSA study who were non-dynapenic at baseline were followed for 4 years. Vitamin D was measured at baseline by the serum concentration of 25(OH)D and classified as sufficient (&gt; 50 nmol/L), insufficient (≥ 30 and ≤ 50 nmol/L) or deficient (&lt; 30 nmol/L). The incidence of dynapenia was determined by a grip strength &lt; 26 kg for men and &lt; 16 kg for women at the end of the 4-year follow-up. Poisson regression models were adjusted by sociodemographic, behavioral, clinical and biochemical characteristics. Serum 25(OH)D deficient was a risk factor for the incidence of dynapenia (IRR = 1.70; 95% CI 1.04-2.79). When only individuals without osteoporosis and those who did not use vitamin D supplementation were analyzed, both serum 25(OH)D deficiency (IRR = 1.78; 95% CI 1.01-3.13) and insufficiency (IRR = 1.77; 95% CI 1.06-2.94) were risk factors for the incidence of dynapenia. In conclusion, a serum level of 25(OH)D &lt; 30 nmol/L is a risk factor for the incidence of dynapenia. Among individuals without osteoporosis and those who do not take vitamin D supplementation, the threshold of risk is higher (≤ 50 nmol/L).

Roles of nutrition in muscle health of community-dwelling older adults: evidence-based expert consensus from Asian Working Group for Sarcopenia

General muscle health declines with age, and in particular, sarcopenia-defined as progressive loss of muscle mass and strength/physical performance-is a growing issue in Asia with a rising population of community-dwelling older adults. Several guidelines have addressed early identification of sarcopenia and management, and although nutrition is central to treatment of sarcopenia, there are currently few guidelines that have examined this specifically in the Asian population. Therefore, the Asian Working Group for Sarcopenia established a special interest group (SIG) comprising seven experts across Asia and one from Australia, to develop an evidence-based expert consensus. A systematic literature search was conducted using MEDLINE on the topic of muscle health, from 2016 (inclusive) to July 2021, in Asia or with relevance to healthy, Asian community-dwelling older adults (≥60 years old). Several key topics were identified: (1) nutritional status: malnutrition and screening; (2) diet and dietary factors; (3) nutritional supplementation; (4) lifestyle interventions plus nutrition; and (5) outcomes and assessment. Clinical questions were developed around these topics, leading to 14 consensus statements. Consensus was achieved using the modified Delphi method with two rounds of voting. Moreover, the consensus addressed the impacts of COVID-19 on nutrition, muscle health, and sarcopenia in Asia. These statements encompass clinical expertise and knowledge across Asia and are aligned with findings in the current literature, to provide a practical framework for addressing muscle health in the community, with the overall aim to encourage and facilitate broader access to equitable care for this target population.

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.

The relationship between vitamin D deficiency, body composition, and physical/cognitive functions

Vitamin D deficiency is still an important subject due to its significant effects on various tissues and functions. We found a relationship between vitamin D deficiency and increase in adipose tissue thicknesses. This situation reveals the importance of vitamin D supplementation, the harms of weight gain and obesity, and the importance of a balanced diet.

PURPOSE

Although the relationship between vitamin D (VitD) levels with body composition and physical/cognitive functions have been investigated in various studies, however, there is no study evaluating all these parameters together. In accordance with, we aimed to evaluate the relationship between VitD deficiency with body composition (i.e., skin, subcutaneous fat, and muscle thicknesses) and physical/cognitive functions.

METHODS

A total of 203 adults (78 M, 125 F, aged 19-91 years) who had recent 25-OH-vitamin D measurements were included. Ultrasonographic (US) measurements (skin, subcutaneous fat, and muscle thicknesses) were made from the dorsum of the hand, and anterior sides of forearm, arm, and thigh. Handgrip strength, gait speed, Timed Up and Go Test, and Chair Stand Test were evaluated. Additionally, cognitive status was also evaluated with Mini-Mental State Exam.

RESULTS

Subjects were classified as VitD deficient group (< 20 ng/ml, N = 125) and control group (≥ 20 ng/ml, N = 78). The groups were not significantly different as regards age, gender, and anthropometric measurements (all p > 0.05). Subcutaneous fat tissues were thicker in the VitD deficient group (all p < 0.05). All the other US measurements and functional/cognitive tests were not significantly different between the groups (all p > 0.05). According to linear regression analyses, body mass index (BMI) was independently related with all subcutaneous fat thicknesses in both genders, and VitD deficiency was related with all subcutaneous fat thicknesses in females and anterior forearm subcutaneous fat thickness in males (all p < 0.05).

CONCLUSION

We imply that together with BMI, VitD deficiency is independently related with increased regional subcutaneous fat tissue. We also underscore the role of US measurements for evaluation of body composition in related clinical scenarios.

Effect of Exercise Training on 1,25(OH)2D Levels: The FIT-AGEING Randomized Controlled Trial

BACKGROUND

Vitamin D deficiency is currently endemic worldwide and is considered as an important factor in the development of several chronic conditions. Physical exercise has been postulated as an auspicious strategy to counteract age-related disorders preventing premature mortality. However, the effects of chronic exercise training on 1,25-dihydroxyvitamin D [1,25(OH)₂D] is unclear. This 12-week randomized controlled trial aimed to investigate the effects of different training modalities on 1,25(OH)₂D in healthy sedentary adults.

HYPOTHESIS

Exercise training will increase 1,25(OH)₂D in the study cohort.

STUDY DESIGN

Randomized controlled clinical trial.

LEVEL OF EVIDENCE

Level 1.

METHODS

A total of 89 healthy sedentary adults (53% women; 53.5 ± 4.9 years old) were enrolled in the FIT-AGEING study. The participants were randomized to (1) a control group (no exercise), (2) physical activity recommendation from the World Health Organization (PAR group), (3) high-intensity interval training (HIIT group), and (4) HIIT adding whole-body electromyostimulation training (HIIT + EMS). 1,25(OH)₂D plasma levels were measured using a DiaSorin Liaison immunochemiluminometric analyzer.

RESULTS

Compared with the control group, 1,25(OH)₂D increased in PAR (Δ = 10.99 ± 3.44 pg/mL; P = 0.01), HIIT (Δ = 11.63 ± 3.51 pg/mL; P = 0.009), and HIIT + EMS groups (Δ = 14.01 ± 3.59 pg/mL; P = 0.001) without statistical differences between them (all Ps > 0.1).

CONCLUSION

In summary, the results show that a 12-week exercise intervention produced an increment of 1,25(OH)₂D independently of age, sex, and exercise modality in healthy sedentary adults.

CLINICAL RELEVANCE

The implementation of physical exercise could be considered a strategy not only aiming to reverse the seasonal decrease of 1,25(OH)₂D in winter explained by low sunlight exposure but also for obtaining subsequent increases of this hormone even in these a priori adverse conditions.

Serum vitamin D status inversely associates with a prevalence of severe sarcopenia among female patients with rheumatoid arthritis

Sarcopenia is an age-related disease with an increased risk of mortality. It is emerging that low serum 25-hydroxyvitamin D [25(OH)D] affects the sarcopenic state in general, but in rheumatoid arthritis (RA), these associations are not understood although the prevalence of vitamin D insufficiency is high in RA. We conducted a cross-sectional study of older female outpatients from our cohort (KURAMA) database. We measured skeletal muscle mass, handgrip strength, and gait-speed to diagnose severe sarcopenia. The serum 25(OH)D concentration was measured using electrochemiluminescence immunoassay. A total of 156 female patients with RA (sarcopenia:44.9%, severe sarcopenia: 29.5%, and without sarcopenia: 25.6%) were enrolled. Classification of vitamin D status at a cutoff point of median 25(OH)D concentration revealed that low 25(OH)D status was associated with a high prevalence of severe sarcopenia and with low measured values of muscle mass, handgrip, and gait speed. Furthermore, multivariable logistic regression analysis identified that low 25(OH)D status was associated with a high prevalence of severe sarcopenia (OR 6.00; 95% CI 1.99-18.08).The same association was observed when the cut-off value was set at 20 ng/ml. In components of sarcopenia, both low physical performance and muscle mass were associated with low 25(OH)D status. In conclusion, vitamin D status was inversely associated with severe sarcopenia, low physical performance, and low skeletal muscle mass. Modification of vitamin D status including vitamin D supplementation should be investigated as a therapeutic strategy for sarcopenic patients with RA.

Relationship of sedentary time, physical activity and fitness with 1,25-dihydroxyvitamin D in middle-aged sedentary adults: The FIT-AGEING study

PURPOSE

Potential interactions between sedentary behaviour, physical activity (PA), and physical fitness with 25-hydroxyvitamin D (25(OH)D) status have been previously suggested. However, data are scarce concerning the association between these predictors of general health and the main active metabolite of vitamin D, the 1,25-dihidroxyvitamin D (1,25(OH)₂D). This study aimed to analyse the relationship of sedentary time, PA levels, and physical fitness (i.e., maximal oxygen uptake (VO₂max) and muscular strength) with 1,25(OH)₂D in middle-aged sedentary adults.

METHODS

A total of 73 (39 women) middle-aged sedentary adults (53.7 ± 5.1 years old) participated in this cross-sectional study. Sedentary time and PA intensity levels were objectively measured with triaxial accelerometers for 7 consecutive days. VO₂max was determined by a maximum treadmill test. Lower and upper limb muscular strength was assessed by an isokinetic strength test and by a handgrip strength test, respectively. 1,25(OH)₂D plasma levels were measured using a DiaSorin Liaison® immunochemiluminometric assay.

RESULTS

No significant relationships were found between objectively measured sedentary time, PA levels or physical fitness (i.e., VO₂max, extension and flexion peak torque, and hand grip strength) and 1,25(OH)₂D (all P > 0.05). All results persisted after controlling for age, sex, fat mass or energy, vitamin D, calcium, and phosphorus intake.

CONCLUSIONS

In summary, our results show that vitamin D status is not affected by physical activity habits and sedentary behaviour in middle-aged sedentary adults.

Serum 25-hydroxyvitamin D in relation to disability in activities of daily living, mobility, and objective physical functioning among Chinese older adults

OBJECTIVES

Vitamin D deficiency is common among older adults, but its association with physical function is not fully understood. The aim of this study was to investigate the associations between serum 25-hydroxyvitamin D and disability in activities of daily living (ADL), mobility, and objective physical functioning among Chinese older adults.

METHODS

We used cross-sectional data of 2225 older adults (≥65 years) who participated in the 2011/2012 main survey of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) and the 2012 biomarker sub-study. Serum levels of 25-hydroxyvitamin D were measured by enzyme immunoassay. Outcomes included ADL disability, mobility disability, and disability in three objective physical examinations (standing-up from a chair, picking-up a book from the floor, and turning-around 360°).

RESULTS

The multiple regression models suggested that participants in the serum 25-hydroxyvitamin D deficiency group had higher odds of ADL disability (OR: 4.08; 95% confidence interval (CI): 2.81, 5.92), mobility disability (OR: 1.59; 95% CI: 1.05, 2.41), and disability in standing-up from a chair (OR: 2.43; 95% CI: 1.60, 3.69), picking-up a book from the floor (OR: 3.09; 95% CI: 2.07, 4.60), and turning-around 360° (OR: 3.09; 95% CI: 2.07, 4.60). Subgroup analyses revealed that some of the above associations (particularly those with mobility disability and disability in turning-around 360°) were only statistically significant among the oldest-old.

CONCLUSIONS

Among the oldest-old in China, serum 25-hydroxyvitamin D deficiency was associated with disability in ADL, mobility, and objective physical functioning, highlighting the importance of managing the serum 25-hydroxyvitamin D level to promote healthy aging.

Vitamin D Deficiency is Associated with Handgrip Strength, Nutritional Status and T2DM in Community-Dwelling Older Mexican Women: A Cross-Sectional Study

The aim of this study was to evaluate the association between handgrip strength, nutritional status and vitamin D deficiency in Mexican community-dwelling older women. A cross sectional study in women ≥ 60 years-old was performed. Plasma 25-hydroxyvitamin D (25(OH)D) concentrations were measured by a quantitative immunoassay technique. Handgrip strength was assessed using a dynamometer, while nutritional status was assessed through the Full Mini Nutritional Assessment (Full-MNA). A total of 116 women participated in the study, their mean age was 70.3 ± 5.8 years; 49.1% of the study group had plasma 25(OH)D levels lower than 40 nmol/L [16 ng/mL]. Meanwhile, 28.45% of participants had low handgrip strength (<16 kg), and 23.1% were identified at risk of malnutrition/malnourished according with Full-MNA score. Women with 25(OH)D deficiency (<40 nmol/L [16 ng/mL]) were more likely to have low handgrip strength (OR = 2.64, p = 0.025) compared with those with higher 25(OH)D values. Additionally, being malnourished or at risk of malnutrition (OR = 2.53, p = 0.045) or having type 2 diabetes mellitus (T2DM) (OR = 2.92, p = 0.044) was also associated with low 25(OH)D. The prevalence of low plasma 25(OH)D concentrations was high among Mexican active older women. Low handgrip strength, being at risk of malnutrition/malnourished, or diagnosed with T2DM was also associated with Vitamin D deficiency.

Relationship between handgrip strength and albuminuria in community-dwelling elderly Japanese subjects: the Shika Study

PURPOSE

This study aimed to investigate the association between handgrip strength (HGS) and albuminuria in the general population of Japan as per sex and age.

METHODS

This population-based, cross-sectional study enrolled 916 Japanese participants aged ≥40 years. Albuminuria was measured and expressed as the urinary albumin-to-creatinine ratio (UACR). Biochemical, nutritional, and anthropometric profiles as well as HGS were measured using standardised protocols.

RESULTS

Four hundred and thirty-two (47%) of the study participants were men, and 484 were women, with respective mean ages of 62 ± 11 years and 63 ± 11 years. HGS, older age, high body mass index, presence of hypertension or diabetes, and a decreased estimated glomerular filtration rate were correlated with the log-transformed UACR in subjects of both sexes. Multivariate linear regression analysis showed that HGS was independently associated with the log UACR in both, men [beta coefficient -0.43; 95% confidence interval (CI) -0.73, -0.13] and women (beta coefficient -0.50; 95% CI -0.90, -0.10) aged ≥65 years; however, a similar association was not observed in younger participants.

CONCLUSION

Low HGS was associated with albuminuria in older men and women in Japan.

Nutrition and Muscle Strength, As the Key Component of Sarcopenia: An Overview of Current Evidence

Much has been achieved by recent research to increase understanding of the links between nutrition and muscle health. Focusing on muscle strength as the key component of sarcopenia, the aim of this overview was to evaluate its links to nutrition, both to variation in habitual diets in older populations, as well as considering supplementation effects in trials. A main message from the reviewed studies is that while many provide suggestive evidence of benefits of higher nutrient intakes and diets of higher quality, findings are inconsistent, and data on muscle strength are often lacking. To assess the potential of optimising diets as a strategy to promote and maintain muscle strength, gaps in current evidence need to be addressed. These include the need for (i) better understanding of individual differences in responsiveness to dietary change, and the need for targeted nutritional support; (ii) clearer distinction between protective and therapeutic actions of diet; and (iii) definition of the role of dietary patterns and their influence on muscle strength, to allow effects of changes in food consumption to be evaluated—particularly when combined with physical activity. Development of this evidence is needed to enable translation into appropriate dietary recommendations for older populations.

Bone Mineral Metabolism Status, Quality of Life, and Muscle Strength in Older People

As the relationship between vitamin D and various diseases or health conditions has become known, interest in the contribution of vitamin D to overall health-related quality of life (QoL) has increased. We examined the relationship between vitamin D status and QoL in 273 participants aged 65 years and older. Serum levels of total calcium, phosphorus, intact parathyroid hormone, albumin, and 25-hydroxyvitaminD3 were analyzed. We also recruited data for QoL, physical activity, nutritional impairment, and muscular strength. Ninety percent of the subjects were classified as vitamin D deficient or insufficient. Participants with higher serum 25(OH)D3, calcium, phosphorous, and Alb levels were significantly less likely to self-report depression or anxiety after adjustment (p = 0.009, p = 0.005, p = 0.003, and p = 0.005, respectively). Additionally, we found an association between lower levels of albumin and self-reported problems with mobility or usual activities (p = 0.01). We also found associations between better muscle strength and higher levels of vitamin D, calcium, phosphorous, and albumin (p = 0.006, p = 0.003, p = 0.004 and p = 0.002, respectively). Overall, our data provide evidence that serum vitamin D and Alb levels are negatively related to self-reported anxiety or depression, usual activities, mobility, and three dimensions of QoL in older adults. Furthermore, vitamin D levels are positively related to hand grip strength in adults over 65 years old.