Low grip strength predicts incident diabetes among mid-life women: the Michigan Study of Women's Health Across the Nation

Grip strength, metabolic syndrome, and type 2 diabetes mellitus: a prospective study

Objectives

This study examines the impact of absolute grip strength (AGS) and relative grip strength (RGS) on the risk of developing type 2 diabetes mellitus (DM), especially in relation to metabolic syndrome (MetS).

Methods

1,935 participants were adults aged 51 to 81 years with an average observation period of 6.50 years. The diagnosis of DM was based on American Diabetes Association. The JAMA 5030J1 dynamometer was used to measure the grip strength. Multivariable extended Cox regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI) for DM incidence.

Results

The DM risk increased with the number of MetS risk factors. High AGS was associated with a reduced DM risk (HR = 0.66, 95% CI = 0.44-0.99), but association disappeared when adjusted for MetS. High RGS was significantly associated with a reduced risk of DM incidence (HR = 0.49, 95% CI = 0.33-0.72), even after adjusting for MetS (HR = 0.63, 95% CI = 0.42-0.94). With the presence of MetS, higher AGS was associated with a greater increase in the DM risk compared to lower AGS, while higher RGS was associated with a less increase in the DM risk compared to lower RGS.

Conclusion

This study demonstrates that RGS is a more reliable predictor of DM risks than AGS. Additionally, MetS significantly increases DM risk, particularly in individuals with obesity and hypertension. The study highlights the importance of assessing muscle quality in DM prevention and suggest that improving muscle quality may help mitigate DM risk.

Investigation of the Effect of Tai Chi Training on Depressive Symptoms in Perimenopausal Women on the Basis of Serum Kynurenine Metabolites

OBJECTIVE

To observe the effects of Tai Chi training on depression symptoms and serum kynurenine metabolites in perimenopausal women and explore the mechanism of Tai Chi training in anti-depression.

METHODS

A total of 72 perimenopausal women with depression were randomly selected from Lishi District and divided into a Tai Chi training group (36 cases) and a control group (36 cases). At the same time, 36 perimenopausal healthy women were randomly selected as the normal group. The Tai Chi training group was intervened with 24 simplified Tai Chi exercises, and the depression self-rating scale was used to evaluate the depression status. The levels of tryptophan (Trp) and kynurenine (KYN) metabolites in serum were determined by high-performance liquid chromatography-ultraviolet detection.

RESULTS

Before the experiment, compared with the normal healthy group, the depression self-rating scale scores, serum KYN and quinolinic acid (QUIN) levels, and KYN/Trp ratio of the control group and Tai Chi group were significantly increased (p < .01), and the serum kynurenic acid (KYNA) level was significantly decreased (p < .01). After the experiment, compared with the normal healthy group, the depression self-rating scale scores of the Tai Chi group were significantly decreased (p < .01), the serum KYNA content was increased (p < .01), the serum KYN and QUIN contents were significantly decreased (p < .01), and the KYN/Trp ratio was significantly decreased (p < .01).

CONCLUSION

Tai Chi training can significantly improve depression symptoms in perimenopausal women. The mechanism of Tai Chi training in improving depression symptoms in perimenopausal women may be achieved by regulating abnormal kynurenine metabolism.

Unraveling the role of muscle mass and strength in predicting type 2 diabetes risk: a systematic review

INTRODUCTION

Skeletal muscle is the largest insulin-sensitive tissue in the human body, alteration in muscle mass and strength substantially impact glucose metabolism. This systematic review aims to investigate further the relationship between muscle mass and strength towards type 2 diabetes mellitus (T2DM) incidence.

METHODS

This systematic review included cohort studies that examinedthe relationship between muscle mass and/or muscle strength on T2DM incidence. A comprehensive search was conducted across PubMed, EBSCO, ProQuest, and Google scholar employing specific Medical Subject Headings (MeSH) and relevant keywords related to or synonymous with "muscle mass", "muscle strength", and "Type 2 Diabetes Mellitus incidence".

RESULTS

Twenty-five cohort studies were included, 11 studies on muscle mass and 16 studies on muscle strength. Participants included were 278,475 for muscle mass and 400,181 for muscle strength. Skeletal muscle mass normalized to body weight (SMM/BW), appendicular skeletal musce mass normalized to body weight (ASM/BW), and handgrip strength normalized to body mass index (HGS/BMI) consistently demonstrate significant inverse association with T2DM even after sex and/or BMI stratification. Handgrip strength normalized to body weight (HGS/BW) demonstrates a strong inverse association with T2DM incidence, however, adiposity should be considered.

CONCLUSION

Muscle mass and strength demonstrate strong association with T2DM incidence. Adiposity, a key T2DM risk factor, should also be assessed through a simple BMI or a sophisticated technique with BIA or CT-scan. The combination of muscle variables and adiposity could further enhance T2DM risk assessment. However, T2DM risks are multifactorial, with various contributing factors, further large-scale studies are needed to validate these findings.

The association between handgrip strength and metabolic syndrome: A large prospective Chinese cohort study

OBJECTIVES

Many studies have explored the association between handgrip strength and metabolic syndrome; however, the findings are inconsistent due to the different types of indicators used to assess handgrip strength (absolute vs. relative handgrip strength). This prospective cohort study aimed to simultaneously investigate the associations of both absolute and relative handgrip strength with metabolic syndrome, and to compare the predictive abilities of these two measures among Chinese adults.

METHODS

Cox proportional hazards regression models were used to analyze 15,820 participants (49.7 % men) living in Tianjin, China. Handgrip strength was measured using a handheld dynamometer. Relative handgrip strength was normalized to body weight (kg).

RESULTS

During the 6-year follow-up, there were 3385 incident cases of metabolic syndrome. The fully adjusted hazards ratios (95 % confidence interval) of the incidence of metabolic syndrome for increasing quartiles of relative handgrip strength were: 1.000 (reference), 0.871(0.780, 0.973), 0.675(0.602, 0.757), 0.454(0.401, 0.513) in men and 1.000 (reference), 0.830(0.714, 0.966), 0.561(0.471, 0.668), and 0.369(0.301, 0.452) in women (both P for trend <0.0001). The optimal cut-off of relative handgrip strength to predict incident metabolic syndrome was 0.563 kg/kg in men (sensitivity = 64.3 %, specificity = 55.6 %) and 0.436 kg/kg in women (sensitivity = 57.0 %, specificity = 69.3 %).

CONCLUSIONS

This large cohort study showed that higher relative handgrip strength, but not absolute handgrip strength, was associated with a lower risk of metabolic syndrome. Although handgrip strength may not be highly sensitive in screening for metabolic syndrome, it remains a valuable predictive tool due to its convenience, ease of measurement, and cost-effectiveness.

Financial strain measures and associations with adult health: A systematic literature review

Despite growing attention to other social needs like food and housing insecurity, financial strain, defined as having difficulty making ends meet or lacking money for basic needs, is under-recognized. Inconsistent labels and measures have made the literature difficult to unify. We used many synonyms for financial strain to systematically identify 199 U.S. studies (316 papers) that used financial strain measures that were operationally consistent with our definition as predictors of health among adults. We thematically coded financial strain measures for content and synthesized evidence based on measure and methods. Financial strain was measured by self-reported lacking money for basic needs (119 studies) and/or difficulty making ends meet (n = 132), and less commonly additionally based on coping strategies (n = 23), satisfaction with finances (n = 14), worry about finances (n = 22), the anticipation of strain (n = 14), and/or lacking money for leisure (n = 29). Regardless of measure, financial strain was associated with poorer mental, physical, biological, and functional health, worse health behaviors and more social needs. Associations were found across diverse and population-based samples and when accounting for other socioeconomic factors and even intermediating health factors. Results demonstrate predictive validity for two different one-item screening tools. Furthermore, the vast evidence linking financial strain to health highlights an urgent need for policy action addressing financial strain to advance health equity.

Handgrip strength and diabetes in postmenopausal women: insights from the Korean National Health and Nutrition Examination Survey 2014-2019

OBJECTIVE

This study aimed to investigate the association between handgrip strength (HGS) and diabetes mellitus (DM) in postmenopausal women in Korea relative to the menopausal duration.

METHODS

Data from the Korean National Health and Nutrition Examination Survey conducted between 2014 and 2019 were analyzed. A total of 4,098 postmenopausal women aged 45 to 65 years were included in the study. Handgrip strength was measured using a digital hand dynamometer. Participants were categorized into quartiles based on HGS with Q1 representing the weakest strength and Q4 the greatest strength. The association between DM and HGS was assessed using logistic regression analysis while adjusting for relevant covariates.

RESULTS

Postmenopausal women aged 45 to 65 years with stronger HGS were less likely to have DM ( P < 0.001). This association persisted even after adjusting for age, body mass index, and comorbidities ( P < 0.001). The inverse relationship between HGS and DM prevalence was more pronounced in women who had been postmenopausal for >10 years than in those who had been postmenopausal for a shorter duration (P-interaction <0.001). In addition, compared to their nondiabetic counterparts, women with DM were less likely to be categorized into the Q4 group ( P < 0.001).

CONCLUSIONS

The findings suggest that weaker HGS was associated with likelihood of having DM among postmenopausal women in Korea. Owing to the inherent limitation to the cross-sectional study design, further research is warranted to elucidate the underlying mechanisms of the association between DM and HGS in postmenopausal women.

Monitoring handgrip strength to motivate lifestyle choices for patients with diabetes type 2 - a pragmatic randomised controlled trial

METHODS

Measurement of HGS with Jamar dynamometers was added to annual check-ups for patients with T2DM by diabetes nurses in primary care with feedback about normal values for age and sex in the intervention group. The control group had standard check-ups. Change in self-reported PA level was measured with questionnaires.

RESULTS

Seven clinics and 334 patients participated. The intervention led to similar effects on PA in both groups. Patients with T2DM had comparable HGS to the general public. Regression analyses showed statistically significantly higher HGS in the intervention group than in the control group at follow-up and no improvement in PA, HbA1c, or waist circumference. Increased HGS was found for older people, men, and people with normal-to-high inclusion HGS, while patients with low inclusion HGS reduced their strength levels.

CONCLUSIONS

Measuring HGS and giving feedback to patients with T2DM can lead to increased HGS but does not seem to affect general PA level, HbA1c, or waist circumference. People over 65 years, men, and people with normal-to-high HGS were influenced positively by the intervention. Patients with low HGS may need personalised support to increase physical activity and improve function.ClinicalTrials registration: NCT03693521.

Urinary pentosidine as a potential biomarker of muscle and physical performance in young adult men

Pentosidine is representative of the cross-linked structure of advanced glycation end products (AGEs) and has been suggested as a biomarker to assess bone and muscle quality. As studies on pentosidine in young adult men remain limited, we aimed to clarify the associations of urinary pentosidine with musculoskeletal status and physical performance in young men. Participants in this study comprised 32 men (age range: 19-39 years). Anthropometric measurements (body composition by InBody 430; stiffness index by ultrasound), muscle performance (grip strength by dynamometer, thigh muscle thickness by ultrasound), physical performance (functional reach test, 30-s chair stand test, and timed up and go test), and urinary biomarkers (pentosidine, N-telopeptide of type I collagen, and creatinine) were measured. In partial correlation analysis adjusted for age and height, higher urinary pentosidine levels were significantly associated with lower fat-free mass index (rho = - 0.368, p = 0.046), grip strength (rho = - 0.433, p = 0.017), rectus femoris thickness (rho = - 0.393, p = 0.032), and anterior thigh thickness (rho = - 0.416, p = 0.022), and a marginally inverse correlation was noted between urinary pentosidine levels and functional reach test (rho = - 0.327, p = 0.078). Our findings suggest that pentosidine correlates inversely with a few muscle and physical performance indicators. Pending future validations, urinary pentosidine may be a biomarker of AGEs in young men.

Comparison of Absolute and Relative Grip Strength to Predict Incidence of Diabetes Mellitus in Korea: A Prospective Cohort Study

Background: This study aimed to investigate the association between absolute grip strength (AGS), relative grip strength (RGS) levels, and the risk of developing diabetes in middle-aged adults, utilizing longitudinal data. Methods: A total of 1935 participants, 51-81 years of age, were engaged in surveys both in 2017-2018 and during the subsequent follow-up survey in 2019-2020. Diabetes diagnosis and treatment were the criteria for categorizing individuals as "diabetic." Grip strength was measured using the JAMA-5030J1 equipment (SAEHAN, Korea), and AGS and RGS were also categorized into tertiles by gender. A proportional hazards Cox regression model was used to evaluate the relationship among AGS, RGS, and the risk of developing diabetes. Subsequently, we computed the hazard ratio (HR) and 95% confidence interval (95% CI) for the risk of developing diabetes. Results: After adjusting for various confounding variables, a significant reduction in diabetes risk was observed in the high grip strength group, adjusted for body mass index (RGS1) and body weight (RGS2), compared with the low RGS1 and RGS2 groups (RGS1 HR = 0.54, 95% CI = 0.36-0.80; RGS2 HR = 0.50, 95% CI = 0.34-0.73). However, there were no significant associations between AGS and diabetes risk. Furthermore, significant differences in the relationship among AGS, RGS levels, and the risk of developing diabetes were found across gender and insulin resistance levels. Conclusion: This study underscores the importance of RGS levels in predicting the incidence of diabetes, with AGS, RGS1, and RGS2 emerging as significant predictive indicators for assessing diabetes risk.

Weight Gain in Midlife Women

PURPOSE OF REVIEW

To summarize the evidence and clinical implications of weight and body composition changes during midlife in women and provide an overview of weight gain prevention and management in this population.

RECENT FINDINGS

Aging-related changes such as decreased energy expenditure and physical activity are important culprits for weight gain in midlife women. The hormonal changes of menopause also influence body adiposity distribution and increase central adiposity. These body changes can have health consequences including the development of cardiometabolic diseases, osteoarthritis, cancer, worsening in cognition, mental health, and menopause symptoms. Midlife women experience changes related to aging, menopause, and lifestyle which favor weight gain. Clinical practice should focus on early counseling and anticipatory guidance on the importance of dietary changes and physical activity to attenuate this phenomenon. Future research should focus on the longitudinal relationship between weight trends in midlife and health consequences and mortality.

Longitudinal Changes in Physical Function and Their Impact on Health Outcomes in COVID-19 Patients

BACKGROUND

Coronavirus disease (COVID-19) is correlated with a variety of long-term sequelae that affect different aspects of health, including physical function. This study investigated the longitudinal changes in handgrip strength (HGS) over six months post-hospital discharge in COVID-19 patients and explores the associations between HGS, health-related quality of life, dyspnoea, exercise capacity, and body mass index (BMI).

METHODS

Adult COVID-19 patients were followed up at one, three, and six months after hospital discharge. HGS, BMI, exercise capacity, and health-related quality of life were assessed. Data from patients with HGS measurements at all three time points were analysed.

RESULTS

Low HGS was prevalent one month post-discharge (35%). Participants with low HGS exhibited more severe disease (30.5% vs. 5.9% were admitted to the intensive care unit, p < 0.01), longer hospital stays (median [IQR] 21 [10.0; 40.5] vs. 12.0 [8.0; 20.0] days, p < 0.01), greater weight loss (-5.7 [-9.1; -0.6] vs. -3.2 [-5.7; -0.0] kg, p = 0.004), and reduced exercise capacity (6 min walking test [6 MWT], 95.7 [84.0; 102.0] vs. 100.0 [92.9; 105.0]% predicted, p = 0.007). Those with persistently low HGS (40% of the initial low HGS group) had worse exercise capacity (6-MWT 93.3 [78.3; 101.0] vs. 101.0 [95.0; 107.0]% predicted, p < 0.001), more dyspnoea (29.0% vs. 2.0% of participants, p < 0.001), poorer quality of life (visual analogue scale score, 75 [50; 75] vs. 85 [75; 95], p < 0.001), and higher rates of problems in various health dimensions. HGS at 1 month was the only significant predictor of HGS improvement from 1 month to 6 months (odds ratio [95% CI] 1.11 [1.03; 1.20], p = 0.008).

CONCLUSIONS

This study highlights the prevalence of reduced physical function among COVID-19 survivors and emphasises the importance of early identification and intervention to optimise their long-term health. Monitoring HGS, a simple and reliable tool, can provide valuable insights into patients' overall physical function, aiding in tailored care and improved outcomes.

Association Between Handgrip Strength and Type 2 Diabetes: A Prospective Cohort Study and Systematic Review With Meta-analysis

BACKGROUND

Both absolute (kg) and relative (kg per kg of body weight) handgrip strength (HGS) have been used as indicators of HGS. Multiple studies have explored HGS associations with type 2 diabetes (T2DM); however, prognostic values were inconsistent. We aimed to examine the associations between both absolute and relative HGS and incident T2DM.

METHODS

A total of 12,957 participants aged 40 years and older (mean age 51.0 years, 58.4% men) were followed and enrolled in the Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) Cohort Study. Cox proportional hazards regression models were used to examine the association of HGS with incident T2DM. Other prospective studies on HGS and risk of T2DM were identified by searching several electronic databases up to November 31, 2021. Meta-analysis was performed by combining the results from the TCLSIH study and previous prospective cohort studies.

RESULTS

From the TCLSIH Cohort study, after adjustment, relative HGS was inversely associated with T2DM (hazard ratio per 0.1 higher relative HGS 0.667, 95% confidence interval [CI] 0.616, 0.722). However, no significant association between absolute HGS and incident T2DM was found. The meta-analyses showed that per 5 kg higher HGS was associated with a 5% (95% CI 2%, 8%) lower risk of T2DM and each 0.1 higher relative HGS was associated with a 22% (95% CI 14%, 29%) lower risk of T2DM.

CONCLUSION

The results from our cohort study and meta-analysis suggest that relative HGS was better than absolute HGS in predicting incident T2DM. Adiposity was an important factor that mediates the association between HGS and T2DM.

Cumulative muscle strength and risk of diabetes: A prospective cohort study with mediation analysis

AIMS

Previous studies assessing the association of muscle strength with risk of diabetes have seldomly accounted for the cumulative exposure over time. This study examined the association of 4-year cumulative muscle strength with risk of diabetes in middle-aged and older adults.

METHODS

We included participants without diabetes, who had 3 repeated measurements of muscle strength, which was assessed by grip strength (normalized by body-weight) and chair-rising time, over 4 years. Cumulative muscle strength was calculated based on trapezoid rule. Logistic regression analysis and mediation analysis for cumulative blood pressure were performed.

RESULTS

We included 3731 and 3799 participants with data on cumulative grip strength and cumulative chair-rising time, respectively. The odds of diabetes were gradually reduced with increments in cumulative grip strength or decrements in cumulative chair-rising time, with the corresponding odds ratio being 0.79 and 0.89 per 1 standard deviation change after multivariable-adjustment. Cumulative systolic blood pressure mediated 10.8% and 14.2% of the associations of diabetes with cumulative grip strength and cumulative chair-rising time, respectively. Cumulative grip strength also correlated inversely with blood pressure, glycemia, and inflammation.

CONCLUSIONS

Higher cumulative muscle strength was associated with lower risk of diabetes and better cardiometabolic health in middle-aged and older Chinese adults.

Grip strength is inversely associated with DNA methylation age acceleration

BACKGROUND

There is a large body of evidence linking muscular weakness, as determined by low grip strength, to a host of negative ageing-related health outcomes. Given these links, grip strength has been labelled a 'biomarker of aging'; and yet, the pathways connecting grip strength to negative health consequences are unclear. The objective of this study was to determine whether grip strength was associated with measures of DNA methylation (DNAm) age acceleration.

METHODS

Middle age and older adults from the 2006 to 2008 waves of the Health and Retirement Study with 8-10 years of follow-up were included. Cross-sectional and longitudinal regression modelling was performed to examine the association between normalized grip strength (NGS) and three measures of DNAm age acceleration, adjusting for cell composition, sociodemographic variables and smoking. Longitudinal modelling was also completed to examine the association between change in absolute grip strength and DNAm age acceleration. The three DNAm clocks used for estimating age acceleration include the established DunedinPoAm, PhenoAge and GrimAge clocks.

RESULTS

There was a robust and independent cross-sectional association between NGS and DNAm age acceleration for men using the DunedinPoAm (β: -0.36; P < 0.001), PhenoAge (β: -8.27; P = 0.01) and GrimAge (β: -4.56; P = 0.01) clocks and for women using the DunedinPoAm (β: -0.36; P < 0.001) and GrimAge (β: -4.46; P = 0.01) clocks. There was also an independent longitudinal association between baseline NGS and DNAm age acceleration for men (β: -0.26; P < 0.001) and women (β: -0.36; P < 0.001) using the DunedinPoAm clock and for women only using the PhenoAge (β: -8.20; P < 0.001) and GrimAge (β: -5.91; P < 0.001) clocks. Longitudinal modelling revealed a robust association between change in grip strength from wave 1 to wave 3 was independently associated with PhenoAgeAA (β: -0.13; 95% CI: -0.23, -0.03) and GrimAgeAA (β: -0.07; 95% CI: -0.14, -0.01) in men only (both P < 0.05).

CONCLUSIONS

Our findings provide some initial evidence of age acceleration among men and women with lower NGS and loss of strength over time. Future research is needed to understand the extent to which DNAm age mediates the association between grip strength and chronic disease, disability and mortality.

Role of advanced glycation end products in the longitudinal association between muscular strength and psychotic symptoms among adolescents

Muscular strength, assessed by handgrip, is a risk indicator for psychiatric disorders, including psychosis. However, the biological mechanisms underlying this association remain unclear. Since advanced glycation end products (AGEs) play a key role in skeletal muscle underdevelopment and psychosis, we examined the role of AGEs in the longitudinal association between muscular strength and psychotic symptoms among adolescents. We first evaluated the direction of the relationship between handgrip strength and urine levels of pentosidine, a representative AGEs in a population-based birth cohort of 1,542 adolescents at ages 12 and 14. Then, we examined the role of AGEs in the longitudinal association between handgrip strength and thought problems (TP), as a psychotic symptom indicator, in a subsample of 256 adolescents at ages 13 and 14. An autoregressive cross-lagged model revealed that handgrip strength at age 12 negatively predicted pentosidine levels at age 14 (β = −0.20, p < 0.001), whereas pentosidine levels at age 12 did not predict handgrip strength at age 14 (β = 0.04, p = 0.062). Moreover, pentosidine levels had a significant indirect effect on the relationship between handgrip strength and TP (standard indirect effect = −0.051, p = 0.012), which remained significant after adjusting for gender and preceded TP and pentosidine levels. Thus, adolescents with low muscular strength are at a high risk of developing psychotic symptoms, which could be mediated by AGEs. Future studies need to investigate whether interventions focused on muscular strength prevent the accumulation of AGEs and thereby prevent the development of psychosis.

Low relative hand grip strength is associated with a higher risk for diabetes and impaired fasting glucose among the Korean population

OBJECTIVE

This study investigated the association between relative hand grip strength (HGS) and glycemic status, such as impaired fasting glucose (IFG) and diabetes, using data from the Korea National Health and Nutrition Examination Survey (KNHANES).

METHODS

We performed a cross-sectional study using the data from the KNHANES of 27,894 individuals from 2014 to 2019. Relative HGS was defined as the absolute HGS divided by body mass index and divided into quartiles in men and women. Odds ratios (OR) for diabetes and IFG were calculated using multivariate logistic regression analysis. All analyses were stratified by sex, and subgroup analysis was age-stratified.

RESULTS

The lowest relative HGS quartile had a significant increase in the risk for diabetes (men: OR 2.72, 95% confidence interval [CI] 2.12-3.50; women: OR 3.38, 95% CI 2.70-4.24) and IFG (men: OR 1.35, 95% CI 1.15-1.59; women: OR 1.60, 95% CI 1.40-1.84). The ORs for diabetes and IFG according to the decreasing quartiles of relative HGS gradually increased in both sexes (P for trend <0.001). ORs and 95% CI of the lowest relative HGS quartile for diabetes were higher in the younger age group than that of the older age group (men: 4.47 and 2.80-7.14 for young adults; 2.41 and 1.37-4.25 for older adults; women: 5.91 and 3.06-9.38 for young adults; 1.47 and 0.92-2.33 for older adults). ORs and 95% CI for IFG was similar with the trend of ORs for diabetes (men: 1.80 and 1.43-2.26 for young adults; 1.17 and 0.75-1.84 for older adults; women: 2.20 and 1.77-2.72 for young adults; 1.33 and 0.86-2.07 for older adults).

CONCLUSION

Lower relative HGS was associated with a higher risk of not only diabetes but also IFG in both sexes. These trends were stronger in younger adults than in older adults.

Combined association of walking pace and grip strength with incident type 2 diabetes

The current study aims to investigate the combined association of walking pace and grip strength with incident type 2 diabetes (T2D). A total of 205 738 participants (mean age 56.6 ± 8.1 years, 115 139 [56.0%] women) without diagnosed or unknown diabetes at baseline from the UK Biobank study were included in this prospective study. Walking pace was self-reported as slow, average, or brisk. Grip strength was measured using a dynamometer and classified as weak, average, and strong. The combined association of walking pace and grip strength with incident T2D was investigated using Cox-proportional hazards models with a 2-year landmark analysis. The additive interaction was conducted by estimating relative excess risk due to interaction (RERI). After the median follow-up period of 5.4 years (interquartile range: 4.8-6.5), 5082 (2.5%) participants were diagnosed with T2D. Compared to brisk-strong individuals (reference group), people who were slow-weak had a higher risk of T2D (hazard ratio: 1.64 [95% CI, 1.42-1.89]) after adjusting for all covariates. There were dose-response gradients across both walking pace and grip strength variables. There was a modest amount of negative additive interaction (RERI; -0.06 [95% CI, -0.16; -0.01]. To conclude, slower pace and weaker grip strength were associated with a higher risk of developing T2D, independent of sociodemographics, lifestyle, and adiposity. Combining walking pace and grip strength might be a practical approach to screening people who are at increased risk of developing T2D.

Musculoskeletal Morbidity Among Adults Living With Spina Bifida and Cerebral Palsy

Background

Individuals living with cerebral palsy (CP) or spina bifida (SB) are at heightened risk for chronic health conditions that may develop or be influenced by the impairment and/or the process of aging.

Objectives

The objective of this study was to compare the incidence of and adjusted hazards for musculoskeletal (MSK) morbidities among adults living with and without CP or SB.

Methods

A retrospective, longitudinal cohort study was conducted among adults living with (n = 15,302) CP or SB and without (n = 1,935,480) CP or SB. Incidence estimates of common MSK morbidities were compared at 4 years of enrollment. Survival models were used to quantify unadjusted and adjusted hazard ratios for incident MSK morbidities. The analyses were performed in 2019 to 2020.

Results

Adults living with CP or SB had a higher 4-year incidence of any MSK morbidity (55.3% vs. 39.0%) as compared to adults without CP or SB, and differences were to a clinically meaningful extent. Fully adjusted survival models demonstrated that adults with CP or SB had a greater hazard for all MSK disorders; this ranged from hazard ratio (HR) 1.40 (95% CI, 1.33 to 1.48) for myalgia to HR 3.23 (95% CI, 3.09 to 3.38) for sarcopenia and weakness.

Conclusion

Adults with CP or SB have a significantly higher incidence of and risk for common MSK morbidities as compared to adults without CP or SB. Efforts are needed to facilitate the development of improved clinical screening algorithms and early interventions to reduce risk of MSK disease onset/progression in these higher risk populations.

Norm Values of Muscular Strength Across the Life Span in a Healthy Swiss Population: The COmPLETE Study

BACKGROUND

Grip strength is used to estimate whole-body strength for health surveillance purposes. Explosive strength is considered important, yet economic measures able to detect early deterioration of neuromuscular capabilities are lacking. Whether handgrip maximum rate of force development (GRFD) or whole-body strength tests are better predictors of lower body power than handgrip maximum strength (GF_max) and their trajectories throughout the life span are unknown.

HYPOTHESIS

GRFD should be more closely related to lower body power than GF_max, and its trajectories over the life span should more closely follow that of lower body power.

STUDY DESIGN

Cross-sectional.

LEVEL OF EVIDENCE

Level 2b.

METHODS

A total of 613 healthy participants aged 20 to 91 years were tested for countermovement jump peak power, GF_max, handgrip rate of force development, and midthigh pull peak force (MTP). Cubic splines and linear models were built for age trajectories, generalized additive models for quintile curves, and linear regression was used to assess predictive quality.

RESULTS

Peak power (P_max) declined linearly to 60% of young adult level, with GRFD, GF_max, and MTP remaining stable up to age 50 years and then declining more sharply to 52% to 71% of young adult levels. Trajectories were similar for male and female participants. GRFD (β = 0.17) and MTP (β = 0.08) were worse predictors of P_max than GF_max (β = 0.24) in models adjusted for age, sex, lean body mass, and vigorous physical activity levels.

CONCLUSION

GRFD was not superior to maximum strength in predicting lower body power. For health surveillance purposes, it therefore appears that GF_max tests are more economical and equally good predictors of lower body explosive strength at older age. The data provided can be used as norm values for healthy subjects.

CLINICAL RELEVANCE

Incorporating countermovement jump testing for early detection of declines in explosive capabilities might be advised.

Normalized Creatinine-to-Cystatin C Ratio and Risk of Diabetes in Middle-Aged and Older Adults: The China Health and Retirement Longitudinal Study

BACKGROUND

Creatinine-to-cystatin C ratio is recently suggested to be a surrogate marker for sarcopenia. However, little is known about its association with diabetes. This study aimed to fill in this gap based on a large-scale prospective cohort.

METHODS

A population-based representative sample of 5,055 participants aged ≥45 years from the China Health and Retirement Longitudinal Study was enrolled between 2011 and 2012 and followed at least once during the subsequent surveys at 2013, 2015, or 2018. Creatinine-to-cystatin C ratio was calculated and normalized by body weight. Incident diabetes was ascertained by plasma glucose, glycosylated hemoglobin, self-reported history, or use of anti-diabetic drugs. Logistic regression analysis and mediation analysis were employed.

RESULTS

During follow-up, 634 participants developed diabetes. The risk of diabetes was gradually and significantly decreased with increased normalized creatinine-cystatin C ratio. The multivariable-adjusted odds ratio for diabetes was 0.91 (95% confidence interval, 0.83 to 0.99) per 1 standard deviation higher of normalized creatinine-to-cystatin C ratio, and this relationship remained significant after controlling for muscle strength. The risk reduction in diabetes was significantly larger in participants with normal-weight and high normalized creatinine-to-cystatin C ratio compared with those with overweight/obesity and high normalized creatinine-to-cystatin C ratio (Pinteraction=0.01). Insulin resistance and inflammation appeared to be key mediators accounting for the observed relationship between normalized creatinine-to-cystatin C ratio and risk of diabetes, with their mediating effect being 93.1% and 22.0%, respectively.

CONCLUSION

High normalized creatinine-to-cystatin C ratio is associated with reduced risk of diabetes in middle-aged and older adults.

The Effects of Passive Simulated Jogging on Parameters of Explosive Handgrip in Nondiabetics and Type 2 Diabetics: A Single Arm Study

Aims

Type 2 diabetes (T2D) is associated with sarcopenia and decreased muscle strength. Explosive and isometric voluntary handgrip strengths (EHGS and HGS) are frequently utilized methods to ascertain health status and a marker of overall muscle strength. We have previously shown that a portable, motorized device, which produces effortless, rapid stepping in place (passive simulated jogging device (JD)), improves glucose homeostasis. This study quantitatively evaluated the effects of JD in modifying parameters of the modified EHGS curve in T2D and nondiabetic (ND) subjects.

Methods

Twenty-one adult participants (11 ND and 10 T2D) (mean age: 41.3 ± 13.5 yr) performed a modified explosive handgrip strength (EHGS) test on study day 1 followed by daily use of JD (90 min per day) for 7 days. The EHGS was repeated after 3 and 7 days' use of JD (JD3 and JD7) and 3 days after completion of JD (Carryover). EHGS curves were analyzed for the following: maximal peak force value (MAX); rate of force development at 25%,75%, and 90% of maximum force; and maximum force (RFD_25%, RFD_75%, RFD_90%, and RFD_max); time to 90%, 75%, and 25% of maximal force (t₉₀, t₇₅, t₂₅) and time to maximal force (t_max); and the integrated area under the curve for force vs. time until task failure (iAUC_TF); and fatigue resistance times at 50% and 25% of maximal force (FR₅₀ and FR25) and fatigue resistance time to task failure (FR_TF).

Results

At baseline, T2D had lower MAX compared to ND. There were no differences at baseline for force development time or fatigue resistance time between T2D and ND. In both T2D and ND, 7 days of JD increased FR₂₅ and FR_TF and iAUC_TF compared to baseline.

Conclusion

JD for at least 7 days prior to EHGS increased time to task failure (fatigue resistance) and iAUC_TF of the force-time curve. JD is a reasonable intervention to decrease sedentary behavior and improve muscle fatigue resistance under various clinical and nonclinical scenarios. This trial is registered with NCT03550105 (08-06-2018).

Changes in objectively-measured physical capability over 4-year, risk of diabetes, and glycemic control in older adults: The China Health and Retirement Longitudinal study

AIMS

High physical capability reduces risk of diabetes, but the association of its changes with risk of diabetes and glycemic control is unclear in older adults. This study aimed to quantify their association.

METHODS

A total of 1,667 participants without diabetes and aged ≥ 60 years from the China Health and Retirement Longitudinal Study were included and followed over 4 years. Physical capability was objectively measured at baseline and 4-year later. Logistic regression models were used to assess the association of changes in physical capability with risk of diabetes.

RESULTS

During follow-up, 160 participants developed diabetes. None of the changes in physical capability expressed in continuous scales or in tertiles was associated with risk of diabetes in unadjusted or adjusted models (all P > 0.05), and no favorable joint effects were observed. Changes in physical capability were not associated with changes in fasting plasma glucose or hemoglobin A1c. Yet increases in walking speed or grip strength were related to reduced metabolic score for insulin resistance (both P ≤ 0.03).

CONCLUSIONS

Increases in objectively-measured physical capability were not associated with reduced risk of diabetes but may ameliorate insulin resistance in older adults. Studies with longer follow-up periods are required to confirm these findings.

Association between relative handgrip strength and abdominal obesity, type-2 diabetes and hypertension in a Mexican population

BACKGROUND

handgrip strength (HGS) is a health-status parameter associated with multicomorbidity in the adult population.

OBJECTIVE

the aim of the present study was to determine the association between HGS (i.e., absolute and relative) and abdominal obesity (AO), type-2 diabetes (T2D), and hypertension (HT), as well as to determine the association between low relative HGS with the presence of multicomorbidity (i.e., the co-occurrence of two or more comorbidities together) in a Mexican population.

METHODOLOGY

a cross-sectional study was carried out in 860 participants from the south of Mexico (661 women and 199 men). The age range evaluated was from 18 to 65 years. Assessments were made of sociodemographic data, clinical history, anthropometric parameters, and measurement of maximal HGS.

RESULTS

the regression models adjusted by age show that the presence of comorbidities (i.e., AO, HT and T2D) was linked negatively to HGS (i.e., absolute and relative). Moreover, in men, a low relative HGS in both hands reported an association with the presence of three simultaneous comorbidities (right, RR: 17.2, p < 0.001; left, RR: 11.92, p = 0.020). In women the same association was found (right, RR: 10.42, p < 0.001; left, RR: 9.90, p < 0.001).

CONCLUSION

lower levels of relative HGS were linked to the presence of simultaneous comorbidities (i.e., the joint presence of AO, T2D and HT). Furthermore, HGS (i.e., absolute and relative) presented an inverse association with individual anthropometric and clinical parameters related to cardiovascular risk in the Mexican population.

Urinary concentrations of phenols and parabens and incident diabetes in midlife women: The Study of Women's Health Across the Nation

BACKGROUND

Environmental phenols have been suggested as diabetogens but evidence from prospective cohort studies is limited. We examined associations between urinary concentrations of phenols and parabens, assessed at two time-points, and incident diabetes in the Study of Women's Health Across the Nation (SWAN).

METHODS

We examined 1,299 women, aged 45-56 years, who were diabetes-free at baseline of the SWAN Multi-Pollutant Study (MPS) (1999-2000) and were followed through January 2017. Urinary concentrations of bisphenol-A, bisphenol-F, triclosan, 2,4-dichlorophenol, 2,5-dichlorophenol, benzophenone-3, methyl-paraben, ethyl-paraben, propyl-paraben, and butyl-paraben were measured twice at MPS baseline and 3 years later (2002-2003), and the two average concentrations were used as exposure variables. Associations of incident diabetes with individual phenols and parabens were examined using Cox regression. We evaluated the overall joint effects using quantile-based g-computation.

RESULTS

Adjusted hazard ratios (HRs) for incident diabetes of the third tertile compared with the first tertile of urinary concentrations were 0.40 (95% confidence interval [CI] = 0.29, 0.56) for methyl-paraben; 0.42 (0.30, 0.58) for propyl-paraben; 0.53 (0.38, 0.75) for 2,5-diclrorophenol; and 0.55 (0.39, 0.80) for benzophenone-3. Nonlinear associations were found for bisphenol-A and 2,4-dichlorophenol (significant positive associations in the second tertile but no associations in the third tertile compared with the first tertile). No significant associations were observed for the other individual chemicals or the joint effect of mixtures.

CONCLUSIONS

Our findings do not support diabetogenic effects of urinary parabens which were inversely associated with incident diabetes among mid-life women. Epidemiologic findings for biomarkers with short half-lives and high within-person variability need to be interpreted with caution.

What can hand grip strength tell us about type 2 diabetes?: mortality, morbidities and risk of diabetes

INTRODUCTION

Hand grip strength (HGS) has been determined as a simple and cost effective method for evaluating overall skeletal muscle strength and quality. It has been used in numerous clinical studies to examine the association between skeletal muscle and type 2 diabetes (T2D). Previous studies have shown that HGS is significantly associated with mortality and cardiovascular disease (CVD) in patients with T2D. As the prevalence of T2D has seen a steady increase globally, HGS measurement can be useful and essential in managing T2D.

AREAS COVERED

This narrative review summarizes the current evidence regarding the association between HGS and T2D. HGS has been considered a useful tool for identifying risks for T2D, CVD, and mortality and evaluating skeletal muscle strength and quality.

OPINION

HGS should be measured in all patients with T2D together with height, weight, and waist circumference. However, there is yet no standard method used in measuring for HGS. T2D patients with a low HGS can engage in resistance training more effectively with appropriate advice based on HGS. Future studies clarifying the genetic association between skeletal muscle and T2D are needed to provide individualized exercise therapy.

Associations between relative grip strength and type 2 diabetes mellitus: The Yangpyeong cohort of the Korean genome and epidemiology study

Objective

To investigate the association between relative grip strength and the prevalence of type 2 diabetes mellitus (T2DM) independently and in combination with body mass index (BMI) in Korean adults.

Methods

The cross-sectional study includes 2,811 men and women (age 40 to 92 years old) with no history of heart disease, stroke, or cancer. Relative grip strength was measured by a handheld dynamometer and calculated by dividing absolute grip strength by body weight. Logistic regression analysis was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of T2DM by sex-specific quintiles of relative grip strength. In a joint analysis, participants were classified into 4 groups: “weak (lowest 20% quintile one) and normal weight (BMI <25.0 kg/m²)”, “weak and overweight/obese (BMI ≥25.0 kg/m²)”, “strong (upper 80% four quintiles) and normal weight” or “strong and overweight/obese”.

Results

Among the 2,811 participants, 371 were identified as having T2DM. Compared with the lowest quintile of relative grip strength (weakest), the ORs (95% CIs) of T2DM were 0.73 (0.53–1.02), 0.68 (0.48–0.97), 0.72 (0.50–1.03), and 0.48 (0.32–0.74) in upper quintiles two, three, four, and five, respectively, after adjusting for BMI and other potential confounders. In the joint analysis, compared with the “weak and overweight/obese” reference group, the odds of T2DM [ORs (95% CIs)] was lower in the “strong and overweight/obese” group [0.65 (0.46–0.92)] and the “strong and normal weight” group [0.49 (0.35–0.67)], after adjusting for potential confounders.

Conclusion

In this cross-sectional study, greater relative grip strength was associated with a lower prevalence of T2DM independent of BMI in Korean adults. Additional prospective studies are needed to determine whether a causal association exists between relative grip strength and T2DM prevalence considering BMI.

Associations between grip strength and incident type 2 diabetes: findings from the UK Biobank prospective cohort study

INTRODUCTION

Grip strength has been associated with chronic diseases and mortality. However, current evidence of the association between grip strength and incident type 2 diabetes mellitus (T2DM) is controversial. The aim of this study was to investigate the associations of absolute and relative grip strength with incident T2DM and whether these associations differ by sociodemographic, lifestyle and adiposity-related factors.

RESEARCH DESIGN AND METHODS

This was a prospective cohort study of 166 894 participants in the UK Biobank (mean age 56.5 years, 54.4% women). The outcome was T2DM incidence and the exposure was grip strength, expressed in absolute (kg) and relative (kg per kg of body weight) values. The association between grip strength and T2DM incidence was investigated using Cox-proportional regression.

RESULTS

The median follow-up was 5.3 years (IQR: 4.7-6.1). During this time, 3713 participants developed T2DM. Lower grip strength was associated with a higher risk of T2DM in both sexes. Those in the lowest quintile of absolute grip strength had a 50% higher risk in men (HR: 1.50 (95% CI: 1.30 to 1.73)) and 25% higher risk in women (HR: 1.25 (95% CI: 1.06 to 1.47)) compared with those in the highest quintile. For relative grip strength, risk of diabetes was more than double for men (HR: 2.22 (95% CI: 1.84 to 2.67)) and 96% higher for women (HR: 1.96 (95% CI: 1.52 to 2.53)) in the lowest compared with highest quintiles.

CONCLUSIONS

Grip strength is associated with a higher risk of T2DM incidence in both men and women independent of important confounding factors including age, deprivation, adiposity and lifestyle. However, the associations were stronger when grip strength is expressed relative to body weight, which could reflect the importance of muscle quality.

Association of a composite score of relative grip strength and timed up and go test with incident type 2 diabetes mellitus: Guangzhou Biobank Cohort Study

Background: We investigated association of a score incorporating relative grip strength (RGS) and timed up and go (TUG) test with incident type 2 diabetes mellitus (T2DM) in older Chinese.

Methods: Both RGS and TUG scores were classified into tertiles (0~2 points) and summed to yield RGS-TUG score, ranging from 0 to 4 points, with higher points indicating better physical function. Cox proportional hazards regression was used to analyze association of RGS-TUG score with incident T2DM.

Results: 3,892 participants without T2DM were followed up for an average of 3.6 years with 240 developing T2DM. After adjustment, those with the lowest RGS-TUG score, versus the highest, had higher fasting glucose, two-hour post-load glucose and glycosylated hemoglobin A1c, with β (95% confidence interval (CI)) being 0.21 (0.08, 0.33), 1.06 (0.69, 1.43) and 0.16 (0.06, 0.27), respectively. In participants with BMI of ≥25 kg/m2, those with the lowest RGS-TUG score showed a higher risk of T2DM (adjusted hazard ratio 3.01, 95% CI 1.04–8.69). No association was found for BMI of 18.5~<25 kg/m2 (P for interaction < 0.05).

Conclusions: This is the first study showing lower RGS-TUG score was associated with increased glycemia and incident T2DM in older people with overweight/obesity. The underlying mechanisms warrant further investigation.

Muscle weakness is a prognostic indicator of disability and chronic disease multimorbidity

BACKGROUND

The objective of this study was to use nationally-representative data on Americans greater than 50 years of age to determine the association between grip strength and inflammation as independent predictors of incident disability, chronic multimorbidity and dementia.

METHODS

Middle age and older adults (n = 12,618) from the 2006-2008 waves of the Health and Retirement Study with 8-years of follow-up were included. Longitudinal modeling was performed to examine the association between baseline grip strength (normalized to body mass: NGS) and high sensitivity C-reactive protein (hs-CRP) (≥3.0 mg/L) with incident physical disabilities (i.e., ≥2 limitations to activities of daily living), chronic multimorbidity (≥2 of chronic conditions), and dementia.

RESULTS

The odds of incident disability were 1.25 (95% CI: 1.20-1.30) and 1.31 (95% CI: 1.26-1.36) for men and women respectively, for each 0.05-unit lower NGS. The odds of incident chronic multimorbidity were 1.14 (95% CI: 1.08-1.20) and 1.14 (95% CI: 1.07-1.21) for men and women respectively for each 0.05-unit lower NGS. The odds of incident dementia were 1.10 for men (95% CI: 1.02-1.20) for each 0.05-unit lower NGS, but there was no significant association for women. Elevated hs-CRP was only associated with chronic multimorbidity among men (OR = 1.29; 95% CI: 1.00-1.73) and women (OR = 1.60; 95% CI: 1.26-2.02).

CONCLUSIONS

Our findings indicate a robust inverse association between NGS and disability and chronic, multimorbidity in older men and women, and dementia in men. Elevated hs-CRP was only associated with chronic multimorbidity in men and women. Healthcare providers should implement measures of grip strength in routine health assessments and discuss the potential dangers of weakness as well as interventions to improve strength with their patients.

Handgrip strength and health outcomes: Umbrella review of systematic reviews with meta-analyses of observational studies

PURPOSE

The aim of the present study was to assess both the credibility and strength of evidence arising from systematic reviews with meta-analyses of observational studies on handgrip strength and health outcomes.

METHODS

An umbrella review of systematic reviews with meta-analyses of observational studies was conducted. We assessed meta-analyses of observational studies based on random-effect summary effect sizes and their p values, 95% prediction intervals, heterogeneity, small-study effects, and excess significance. We graded the evidence from convincing (Class I) to weak (Class IV).

RESULTS

From 504 articles returned in a search of the literature, 8 systematic reviews were included in our review, with a total of 11 outcomes. Overall, nine of the 11 of the outcomes reported nominally significant summary results (p < 0.05), with 4 associations surviving the application of the more stringent p value (p < 10^-6). No outcome presented convincing evidence. Three associations showed Class II evidence (i.e., highly suggestive): (1) higher handgrip values at baseline were associated with a minor reduction in mortality risk in the general population (n = 34 studies; sample size = 1,855,817; relative risk = 0.72, 95% confidence interval (95%CI): 0.67-0.78), (2) cardiovascular death risk in mixed populations (n = 15 studies; relative risk = 0.84, 95%CI: 0.78-0.91), and (3) incidence of disability (n = 7 studies; relative risk = 0.76, 95%CI: 0.66-0.87).

CONCLUSION

The present results show that handgrip strength is a useful indicator for general health status and specifically for early all-cause and cardiovascular mortality, as well as disability. To further inform intervention strategies, future research is now required to fully understand mechanisms linking handgrip strength scores to these health outcomes.

Age-related changes of microbiota in midlife associated with reduced saccharolytic potential: an in vitro study

BACKGROUND

Gut microbiota is critical in maintaining human health, of which diversity and abundance are subject to significantly reduce in seniors. Gut microbiota is reported to be stable across the long adulthood in general, but lack of careful examination, especially for the midlife people.

RESULTS

To characterize the gut microbiota in midlife, we investigated the faecal microbiota between two groups of healthy people, young, 20-39 years old, n = 15; and midlife, 40-60 years old, n = 15. Metabolic responses of the microbiota were studied through in vitro batch fermentation model. Although no difference was observed in the diversity indices between the two age groups, a wide range taxonomic changes were found in the faecal microbiota. Furthermore, substantial Bifidobacterium reduction was also found in both faecal and fermented samples. The faecal SCFAs are similar in both groups, as well as starch fermentation broth. However, after inulin fermentation, the acetate concentration and inulin degradation rate decreased while the gas production increased in midlife group, suggesting a deficiency of saccharolytic potential in midlife, especially for non-digestible carbohydrate.

CONCLUSIONS

Our data demonstrate that gut microbiota begins to change as early as in midlife. The reduction in Bifidobacterium dominates the change of the microbiota composition in midlife resulting in attenuated saccharolytic capacity of inulin, possibly leading to insufficient acetate production which might be associated with healthy problems in this transition period from young to elderly.

Handgrip strength-A risk indicator for type 2 diabetes: Systematic review and meta-analysis of observational cohort studies

AIMS

Evolving debate suggests that handgrip strength (HGS), a measure of muscular strength, might be associated with the risk of type 2 diabetes (T2D); however, the evidence is conflicting. Using a systematic review and meta-analysis of published observational cohort studies in general populations, we aimed to assess the association of HGS with the future risk of T2D.

METHODS

Relevant studies were sought from inception until April 2020 in MEDLINE, Embase, Web of Science, and manual search of relevant articles. Transformed or extracted relative risks (RRs) with 95% confidence intervals (CIs) comparing the top vs bottom thirds of HGS levels were pooled using random effects meta-analysis.

RESULTS

A total of 10 unique observational cohort studies comprising of 177 826 participants and >5167 T2D cases were eligible. The pooled multivariable RR (95% CI) for T2D comparing the top vs bottom thirds of HGS levels was 0.73 (0.63-0.84). This association was consistent across several relevant subgroups except for evidence of effect modification by sample size (P value for meta-regression <.001): evidence of an association in smaller studies (<250 events) 0.50 (0.40-0.63), with no significant association in bigger studies (≥250 events) 0.87 (0.73-1.05). There was no evidence of small study effects using formal tests such as funnel plots and Egger's regression symmetry test.

CONCLUSION

Pooled analysis of observational cohort studies suggests that HGS may be a risk indicator for T2D in the general population. The role of utilizing HGS measurements in T2D prevention strategies warrants further investigation.

Skeletal Muscle and Metabolic Health: How Do We Increase Muscle Mass and Function in People with Type 2 Diabetes?

BACKGROUND

Whilst skeletal muscles' primary role is allowing movement, it has important metabolic roles, including in glycemic control. Indeed, evidence indicates that low muscle mass and function are associated with an increased risk of type 2 diabetes, highlighting its importance in the development of metabolic disease.

METHODS

In this mini-review, we detail the evidence highlighting the importance of muscle in type 2 diabetes and the efficacy of resistance exercise in improving glycemic control alongside our approach to increase uptake of such exercise in people with type 2 diabetes. This summary is based in the authors' knowledge of the filed supplemented by a Pubmed search using the terms "muscle," "glycemic control," "HbA1c," "type 2 diabetes," and "resistance exercise."

RESULTS

The main strategy to increases muscle mass is to perform resistance exercise and, although the quality of evidence is low, such exercise appears effective in reducing Glycated Haemoglobin (HbA1c) in people with type 2 diabetes. However, to increase participation we need to improve our understanding of barriers and facilitators to such exercise. Current data indicate that barriers are similar to those reported for aerobic exercise, with additional resistance exercise specific barriers of looking to muscular, increase risk of cardiovascular event, having access to specialized equipment and knowledge of how to use it.

CONCLUSIONS

The development of simple resistance exercises that can be performed anywhere, that use little or no equipment and are effective in reducing HbA1c will be, in our opinion, key to increasing the number of people with type 2 diabetes performing resistance exercise.

Normalized Hand Grip and Back Muscle Strength as Risk Factors for Incident Type 2 Diabetes Mellitus: 16 Years of Follow-Up in a Population-Based Cohort Study

PURPOSE

Muscle strength is associated with type 2 diabetes mellitus (T2DM). However, it is controversial whether muscle strength and normalized muscle strength is a risk factor for T2DM. Moreover, the relationship of back muscle strength (BMS) and incident T2DM has not been reported. In this study, we investigated the relationship between HGS, BMS, normalized HGS and BMS, and incident T2DM.

METHODS

A total of 2699 non-diabetes subjects aged 40-69 years (1313 women and 1386 men) in the Korean Genome and Epidemiology Study (KoGES) Ansan cohort were followed for 16 years. At the baseline and biennial follow-up visits, fasting glucose, postprandial 2-h glucose, clinical examinations, HGS, and BMS were measured by trained interviewers and examiners. HGS and BMS were measured at baseline. The relationships between incident T2DM, HGS, BMS, and normalized HGS and BMS were estimated using Cox proportional hazard regression models after adjusting for the confounding factors.

RESULTS

HGS and BMS were not associated with incident T2DM in multivariate analysis. However, the hazard ratio (HR) per one standard deviation (SD) increase in the body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR)-normalized HGS, and BMS was associated with a lower risk for incident T2DM in both women and men after adjusting for the confounding factors (HR = 0.842-0.880-fold for women, p ≤ 0.015; HR = 0.887-0.903-fold for men, p ≤ 0.024). In the sub-analysis of menopause status, the HR per one SD increase in BMI, weight^2/3, WC, and WHR-normalized HGS was associated with a lower risk for incident T2DM in both pre- and post-menopausal women after adjusting for the confounding factors (HR = 0.860-0.820-fold for premenopausal, P ≤ 0.006; HR = 0.900-0.867-fold for postmenopausal, p ≤ 0.024). Additionally, we confirmed that the quartile group with higher muscle strength was associated with a lower risk for incident T2DM.

CONCLUSION

The present study suggested that normalized HGS and BMS were associated with a lower risk for the future development of T2DM. Moreover, weak muscle strength in premenopausal women may be the cause of T2DM. Further research is needed to determine whether efforts to improve muscle strength, such as exercise can reduce the risk of T2DM.

Extent of aging across education and income subgroups in Thailand: Application of a characteristic-based age approach

Aim

This study aimed to identify differences in physical performance across various socioeconomic groups within an older population and to convert those differences into a common metric to facilitate comparisons of aging speed across socioeconomic subgroups.

Methods

We employed data from the 2009 National Health Examination Survey of Thailand. Physical performance was assessed using three health characteristics: grip strength, as a measure of upper body strength; walking speed, as a measure of lower body strength; and a combined measure of grip strength and walking speed, to capture the strength of the whole body. Education level and income were used to distinguish socioeconomic subpopulations. We followed a characteristic-based age approach to transform these population characteristics, which were measured in different units, into a common and comparable aging metric, referred to as α − age.

Results

Physical aging trajectories varied by sex and socioeconomic status. Some education, particularly secondary or higher education levels, was significantly associated with greater physical strength in older age for both men and women, whereas higher income was significantly associated with physical strength only for men. Across the three health characteristics, having a primary education slowed age-related declines by up to 6.3 years among men and 2.8 years among women, whereas being in a higher income group slowed age-related declines by 8.2 years among men and up to 4.9 years among women.

Conclusions

This study adds new evidence from a developing Asian country regarding the difference in aging speeds across subpopulations associated with different levels of education and income.

The Relative Handgrip Strength and Risk of Cardiometabolic Disorders: A Prospective Study

Background

This study aims to investigate the association between handgrip strength (HGS) and cardiometabolic disorders (CMD), including hypertension, diabetes, and dyslipidemia, in a prospective study.

Methods

The association between HGS and CMD was examined using the data from 5,271 Chinese adult participants ≥45 years old enrolled in the CHARLS (Chinese Health and Retirement Prospective Cohort Study) during 2011-2015. Relative HGS, calculated as maximal absolute HGS from both hands divided by body mass index, was used in the primary analysis and divided into three groups according to the tertiles (T1, T2, and T3).

Results

The participants with higher relative HGS had a lower risk of hypertension, diabetes, and dyslipidemia than those with lower HGS, although did not reach statistical significance for diabetes and hypertension in males. Participants with higher HGS had significantly lower risk of hypertension [T3 vs. T1: OR = 0.69, 95% CI = 0.51-0.91, P = 0.010] and dyslipidemia (OR = 0.65, 95% CI = 0.51-0.83, P < 0.001) in males. For females, participants with higher HGS had significantly lower risks of dyslipidemia (OR = 0.67, 95% CI = 0.54-0.83, P < 0.001).

Conclusion

A consistent association was observed between higher relative HGS and lower risk of CMD. Further research is required to evaluate whether relative HGS can be a convincing predictor for the occurrence of CMD and as a target for intervention in the high-risk population.

What are the association patterns between handgrip strength and adverse health conditions? A topical review

Measures of handgrip strength can be used to conveniently assess overall muscle strength capacity. Although stand-alone measures of handgrip strength provide robust health information, the clinical meaningfulness to determine prevention and treatment options for weakness remains limited because the etiology of muscle weakness remains unclear. Moreover, clinical outcomes associated with handgrip strength are wide-ranging. Therefore, disentangling how handgrip strength is associated with health conditions that are metabolically or neurologically driven may improve our understanding of the factors linked to handgrip strength. The purpose of this topical review was to highlight and summarize evidence examining the associations of handgrip strength with certain health outcomes that are metabolically and neurologically driven. From this perusal of the literature, we posit that stand-alone handgrip strength be considered an umbrella assessment of the body systems that contribute to strength capacity, and a panoptic measurement of muscle strength that is representative of overall health status, not a specific health condition. Recommendations for future strength capacity–related research are also provided.

Anti-Aging Effects of Schisandrae chinensis Fructus Extract: Improvement of Insulin Sensitivity and Muscle Function in Aged Mice

Schisandrae chinensis Fructus has a long history of medicinal use as a tonic, a sedative, and an antitussive drug. In this study, we investigated the beneficial effects of Schisandrae chinensis Fructus ethanol extract (SFe) on metabolism in an aged mouse model. Sixteen-month-old C57BL/6J mice were fed with a diet supplemented with SFe for 4 months. Insulin sensitivity was lower at 20 months of age than at 16 months of age; however, the decrease in insulin sensitivity was less in SFe-fed mice. SFe supplementation also appeared to improve glucose tolerance. Body weight gain was lower in SFe-fed mice than in mice fed the control diet. Body fat mass was lower and the lean mass was higher in SFe-fed mice. In addition, the grip strength was enhanced in SFe-fed mice. Histological analysis of the tibialis anterior muscle showed that the size of myofiber and slow-twitch red muscle was increased by SFe supplementation. The expression of proteins related to muscle protein synthesis such as phospho-Erk1 and phospho-S6K1 was increased by SFe supplementation. The mRNA expression of genes related to myogenesis and their encoded proteins such as MyoD, Myf5, MRF4, myogenin, and myosin heavy chain, was increased, whereas that of genes related to muscle degradation, such as atrogin-1, MuRF-1, and myostatin, were decreased relative to control mice. These results suggest that SFe supplementation might have beneficial effects for the improvement of insulin sensitivity and inhibition of muscle loss that occur with aging.

The menopause transition and women's health at midlife: a progress report from the Study of Women's Health Across the Nation (SWAN)

OBJECTIVE

Our initial understanding of the menopause transition (MT) has been framed by clinical samples of women seeking treatment rather than by population-based studies. The Study of Women's Health Across the Nation (SWAN) initiated in 1996 with an overall goal to define the MT, to characterize its biological and psychosocial antecedents and sequelae in an ethnically and racially diverse sample of midlife women.

METHODS

This review summarizes the central findings of SWAN to date that can inform women and their healthcare providers about the impact of the MT and midlife aging on overall health and well-being.

RESULTS

SWAN characterized changes in reproductive axis and menstrual cycle patterns that informed the development of the reproductive aging staging system Staging of Reproductive Aging Workshop+10; MT-related symptoms and mental health (vasomotor symptoms, sleep complaints, psychological symptoms, cognitive performance, and urogenital and sexual health); and physiological systems and functions (cardiovascular and cardiometabolic health, bone health, physical function performance) that are influenced by the MT. SWAN demonstrated substantial interrelations among these changes and significant racial/ethnic differences in the rate and magnitude of change in multiple health indictors in midlife women. The findings point to midlife as a critical stage for adopting healthy behavior and preventive strategies.

CONCLUSIONS

Over the past 23 years, SWAN has advanced our understanding of the impact of the MT and midlife aging on health and well-being in women. SWAN will be instrumental to determine whether MT-related changes during midlife are related to unfavorable health and well-being in early old age.

Cardiorespiratory fitness, muscular strength and risk of type 2 diabetes: a systematic review and meta-analysis

AIMS/HYPOTHESIS

The study aimed to quantitatively summarise the dose-response relationships between cardiorespiratory fitness and muscular strength on the one hand and risk of type 2 diabetes on the other and estimate the hypothetical benefits associated with population-wide changes in the distribution of fitness.

METHODS

We performed a systematic review with meta-analysis. The PubMed and EMBASE electronic databases were searched from inception dates to 12 December 2018 for cohort studies examining the association of cardiorespiratory fitness or muscular strength with risk of incident type 2 diabetes in adults. The quality of included studies was evaluated using the Newcastle-Ottawa Scale.

RESULTS

Twenty-two studies of cardiorespiratory fitness and 13 studies of muscular strength were included in the systematic review with both exposures having ten estimates available for the primary adiposity- or body size-controlled meta-analysis. In random-effects meta-analysis including 40,286 incident cases of type 2 diabetes in 1,601,490 participants, each 1 metabolic equivalent (MET) higher cardiorespiratory fitness was associated with an 8% (95% CI 6%, 10%) lower RR of type 2 diabetes. The association was linear throughout the examined spectrum of cardiorespiratory fitness. In 39,233 cases and 1,713,468 participants each 1 SD higher muscular strength was associated with a 13% (95% CI 6%, 19%) lower RR of type 2 diabetes. We estimated that 4% to 21% of new annual cases of type 2 diabetes among 45-64-year-olds could be prevented by feasible and plausible population cardiorespiratory fitness changes.

CONCLUSIONS/INTERPRETATION

Relatively small increments in cardiorespiratory fitness and muscle strength were associated with clinically meaningful reductions in type 2 diabetes risk with indication of a linear dose-response relationship for cardiorespiratory fitness.

REGISTRATION

PROSPERO (CRD42017064526).

The Association Between Differing Grip Strength Measures and Mortality and Cerebrovascular Event in Older Adults: National Health and Aging Trends Study

The purpose of this study was to compare the predictive capacity of different post-processing methods of hand grip strength (GS) for mortality and incident cerebrovascular events in older adults. A sample of 4,143 participants aged 65 years and older was included from the National Health and Aging Trends Study (NHATS) and followed for 6 years. GS measures included baseline (i.e., round 1) (1) absolute GS, (2) GS divided by body mass (NGS_mass), and (3) GS divided by body mass index (NGS_BMI), as well as (4) change in absolute GS from round 1 to round 2 (GS_1-2). Cox proportional hazards regression models were used to examine the association between sex- and age group-specific tertiles of GS measures (weak, moderate-strength, strong) with mortality (n = 641) and incident cerebrovascular events (n = 329). Absolute GS (hazard ratio [HR] = 1.83; 95% confidence interval [CI] = 1.51–2.22), NGS_mass (HR = 1.46; 95% CI = 1.21–1.76), and NGS_BMI (HR = 1.50; 95% CI = 1.24–1.82) were each associated with mortality among weak participants, but not GS_1-2 (HR = 1.10; 95% CI = 0.99–1.46). NGS_mass (HR = 1.54; 95% CI = 1.19–2.01) and NGS_BMI (HR = 1.37; 95% CI = 1.06–1.79) were both associated with incident cerebrovascular event among weak participants, but not absolute GS (HR = 1.12; 95% CI = 0.86–1.47) or GS_1-2 (HR = 1.11; 95% CI = 0.85–1.44). Absolute GS, NGS_mass, and NGS_BMI were each associated with mortality, whereas only NGS_mass and NGS_BMI were associated with cerebrovascular event. These findings suggest that different post-processing methods of GS may have differing predictive capacity in the elderly depending on the outcome of interest; however, since NGS measures were associated with both mortality and cerebrovascular events, they may be considered advantageous for screening in older adults.

Association between handgrip strength, balance, and knee flexion/extension strength in older adults

The objective of the study was to examine the association between handgrip strength (HGS), knee flexion and extension strength, and static and dynamic balance in older women. One hundred and ten women with a mean age of 67.4±5.9 years were assessed for dynamic postural balance using the Time Up & Go Test (TUG) with and without cognitive tasks. Semi-static balance was assessed by means of a force platform; knee flexor and extensor muscle strength was calculated using an isokinetic dynamometer; and HGS using a hand held dynamometer. Weaker HGS was significantly correlated with worse performance in dynamic postural balance, as well as performance with TUG with and without cognitive tasks; however, there was no correlation between HGS and static balance. There was a moderate positive correlation between knee flexion/extension strength and HGS. This suggests that HGS could be used as a proxy indicator of overall strength capacity for clinical screening among older women.