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

Biomarkers of aging: from molecules and surrogates to physiology and function

Many countries face an unprecedented challenge in aging demographics. This has led to an exponential growth in research on aging, which, coupled to a massive financial influx of funding in the private and public sectors, has resulted in seminal insights into the underpinnings of this biological process. However, critical validation in humans has been hampered by the limited translatability of results obtained in model organisms, additionally confined by the need for extremely time-consuming clinical studies in the ostensible absence of robust biomarkers that would allow monitoring in shorter time frames. In the future, molecular parameters might hold great promise in this regard. In contrast, biomarkers centered on function, resilience, and frailty are available at the present time, with proven predictive value for morbidity and mortality. In this review, the current knowledge of molecular and physiological aspects of human aging, potential antiaging strategies, and the basis, evidence, and potential application of physiological biomarkers in human aging are discussed.

A Three-Year Longitudinal Follow-Up Study: Does Mild Cognitive Impairment Accelerate Age-Related Changes in Physical Function and Body Composition?

Age-related declines in physical function, body composition, and cognitive function are interrelated. This prospective study aimed to examine the impact of mild cognitive impairment (MCI) on age-related changes in physical function and body composition among community-dwelling older adults. We analyzed data from 180 older adults (aged ≥70 years) who completed a longitudinal assessment of physical function and body composition in the community. Physical function included grip strength and time taken to walk 10 m at normal and maximum pace. Body composition assessments calculated the body mass index (BMI) and appendicular skeletal muscle index (ASMI) using bioelectrical impedance analysis at baseline and three-year follow-up assessments. MCI was defined as values below the age- and education-adjusted reference threshold in several tests, including memory, attention, executive function, and processing speed. Participants were divided into the MCI and non-MCI groups based on their MCI status at baseline. A two-way repeated-measures analysis of covariance (ANCOVA), adjusting for age and gender, was used to analyze the group (MCI and non-MCI) by time (baseline and three-year follow-up) interaction. Thirty participants (16.7%) had MCI at baseline. The repeated-measures ANCOVA indicated that no variables had significant group by time interactions. Stratified analyses by gender (repeated-measures ANCOVA, adjusted for age) confirmed a significant group by time interaction on BMI (F=5.63, p=0.02) and ASMI (F=6.33, p=0.01) among women. Older women with MCI may experience a greater impact of the acceleration of shrinking and age-related decline in muscle mass. The close associations of MCI with shrinking and muscle mass loss have important implications for targeting interventions among MCI women.

Measuring grip strength in adolescents and adults with cerebral palsy in a clinic setting: Feasibility, reliability, and clinical associations

AIM

To determine the feasibility and reliability of measuring grip strength and its association with anthropometrics and diseases among adolescents and adults (≥16 years old) with cerebral palsy (CP).

METHOD

In this cross-sectional study, individuals with CP, classified in Gross Motor Function Classification System (GMFCS)/Manual Ability Classification System (MACS) levels I to V, were recruited to measure grip strength, anthropometrics, and self-reported current/history of disease during a routine clinical visit. Feasibility was determined as the proportion recruited/consented/completed testing. Test-retest reliability of three maximal effort trials per side was assessed. Linear regression determined associations of grip strength with anthropometrics after adjusting for age, sex, and GMFCS. The predictive ability of GMFCS alone, grip strength alone, GMFCS + grip strength, and GMFCS × grip strength for diseases was compared.

RESULTS

Of 114 individuals approached, 112 participated and 111 successfully completed all tasks. There was good to excellent reliability of test-retest grip strength between trials for dominant and non-dominant sides for the entire cohort and when stratified by each GMFCS and MACS level (intraclass correlation coefficient range 0.83-0.97). Sex, GMFCS, MACS, body mass, and waist circumference were associated with grip strength (p < 0.05), but not hip circumference, waist:hip ratio, or triceps skinfold thickness. Modeling grip strength with GMFCS had a higher predictive value for relevant diseases than GMFCS alone.

INTERPRETATION

Grip strength is a feasible and reliable measurement for CP, and is associated with some demographics and anthropometric measures. Grip strength, in addition to the GMFCS, enhanced prediction of disease outcomes.

WHAT THIS PAPER ADDS

Measurement of hand grip strength is clinically feasible for adolescents/adults with cerebral palsy. Grip strength has good to excellent test-retest reliability across Gross Motor Function Classification System (GMFCS) and Manual Ability Classification System (MACS) levels. Grip strength is associated with sex, weight, waist circumference, GMFCS, and especially MACS. Grip strength, in addition to GMFCS, shows promise for enhancing disease prediction in this cohort.

Risk factors for multimorbidity in adulthood: A systematic review

BACKGROUND

Multimorbidity, the coexistence of multiple chronic diseases in an individual, is highly prevalent and challenging for healthcare systems. However, its risk factors remain poorly understood.

OBJECTIVE

To systematically review studies reporting multimorbidity risk factors.

METHODS

A PRISMA-compliant systematic review was conducted, searching electronic databases (MEDLINE, EMBASE, Web of Science, Scopus). Inclusion criteria were studies addressing multimorbidity transitions, trajectories, continuous disease counts, and specific patterns. Non-human studies and participants under 18 were excluded. Associations between risk factors and multimorbidity onset were reported.

RESULTS

Of 20,806 identified studies, 68 were included, with participants aged 18-105 from 23 countries. Nine risk factor categories were identified, including demographic, socioeconomic, and behavioral factors. Older age, low education, obesity, hypertension, depression, low pysical function were generally positively associated with multimorbidity. Results for factors like smoking, alcohol consumption, and dietary patterns were inconsistent. Study quality was moderate, with 16.2% having low risk of bias.

CONCLUSIONS

Several risk factors seem to be consistently associated with an increased risk of accumulating chronic diseases over time. However, heterogeneity in settings, exposure and outcome, and baseline health of participants hampers robust conclusions.

Prediabetes Progression and Regression on Objectively- Measured Physical Function: A Prospective Cohort Study

BACKGRUOUND

Prediabetes leads to declines in physical function in older adults, but the impact of prediabetes progression or regression on physical function is unknown. This study assessed this longitudinal association, with physical function objectivelymeasured by grip strength, walking speed, and standing balance, based on the Health and Retirement Study enrolling United States adults aged >50 years.

METHODS

Participants with prediabetes were followed-up for 4-year to ascertain prediabetes status alteration (maintained, regressed, or progressed), and another 4-year to assess their impacts on physical function. Weak grip strength was defined as <26 kg for men and <16 kg for women, slow walking speed was as <0.8 m/sec, and poor standing balance was as an uncompleted fulltandem standing testing. Logistic and linear regression analyses were performed.

RESULTS

Of the included 1,511 participants with prediabetes, 700 maintained as prediabetes, 306 progressed to diabetes, and 505 regressed to normoglycemia over 4 years. Grip strength and walking speed were declined from baseline during the 4-year followup, regardless of prediabetes status alteration. Compared with prediabetes maintenance, prediabetes progression increased the odds of developing weak grip strength by 89% (95% confidence interval [CI], 0.04 to 2.44) and exhibited larger declines in grip strength by 0.85 kg (95% CI, -1.65 to -0.04). However, prediabetes progression was not related to impairments in walking speed or standing balance. Prediabetes regression also did not affect any measures of physical function.

CONCLUSION

Prediabetes progression accelerates grip strength decline in aging population, while prediabetes regression may not prevent physical function decline due to aging.

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.

The relationship between clinical measures of cognitive function and grip strength in healthy older adults

BACKGROUND

Handgrip strength is considered a surrogate for musculoskeletal strength, however there is emerging evidence of an association with cognition. The specific neurocognitive attribute which best associates with grip strength is unknown.

METHODS

We performed a secondary analysis on baseline data in 49 healthy older adults. Grip strength was corrected for body mass index. Control independent variables included age, Montreal Cognitive Assessment, and Trails B. Experimental variables included a clinical measure of simple reaction time, and clinical and computerized go/no-go tasks. The clinical Go/No-Go measure was determined with ReacStick, a rod-shaped device which - when released by the examiner - requires the participant to decide within 390 ms whether to catch the device or let it fall to the ground.

RESULTS

Bivariate analysis demonstrated that age and all cognitive measures other than the computer go/no-go response accuracy related to grip strength. Multivariate analyses showed that following inclusion of the control variables, only ReacStick measures (reaction accuracy/simple reaction time) significantly predicted grip strength, explaining an additional 15.90% variance (p = 0.026). In contrast, computerized Go/No-Go accuracy (p = 0.391), response time variability (p = 0.463), and the control variables (p value range = 0.566-0.942) did not predict grip strength.

CONCLUSION

A short latency (< 390 ms) visuomotor Go/No-Go task independently predicted over 15% of grip strength variance, whereas a slower screen-based Go/No-Go task did not. These findings support the notion that declining grip strength likely reflects sub-clinical brain changes as well as musculoskeletal dysfunction, possibly explaining the potent relationships between grip strength, disability, chronic disease, and mortality.

Chemokine-like receptor 1 plays a critical role in modulating the regenerative and contractile properties of muscle tissue

Musculoskeletal diseases are a leading contributor to mobility disability worldwide. Since the majority of patients with musculoskeletal diseases present with associated muscle weakness, treatment approaches typically comprise an element of resistance training to restore physical strength. The health-promoting effects of resistance exercise are mediated via complex, multifarious mechanisms including modulation of systemic and local inflammation. Here we investigated whether targeted inhibition of the chemerin pathway, which largely controls inflammatory processes via chemokine-like receptor 1 (CMKLR1), can improve skeletal muscle function. Using genetically modified mice, we demonstrate that blockade of CMKLR1 transiently increases maximal strength during growth, but lastingly decreases strength endurance. In-depth analyses of the underlying long-term adaptations revealed microscopic alterations in the number of Pax7-positive satellite cells, as well as molecular changes in genes governing myogenesis and calcium handling. Taken together, these data provide evidence of a critical role for CMKLR1 in regulating skeletal muscle function by modulating the regenerative and contractile properties of muscle tissue. CMKLR1 antagonists are increasingly viewed as therapeutic modalities for a variety of diseases (e.g., psoriasis, metabolic disorders, and multiple sclerosis). Our findings thus have implications for the development of novel drug substances that aim at targeting the chemerin pathway for musculoskeletal or other diseases.

Impact on Mental Well-Being and Resilience of Patients with Multiple Chronic Conditions in Different Periods during the Coronavirus Disease 2019 Outbreak in Taiwan

Concerns over the coronavirus disease 2019 (COVID-19) pandemic and control measures have affected the routine outpatient visits of individuals with comorbidities and their mental well-being. From October 2019 to August 2020, this cross-sectional study enrolled 135 patients who sought medical attention at a medical center in Taiwan. This period covered the early (October to December 2019), peak (January to April 2020), and late (May to August 2020) periods of the COVID-19 outbreak in Taiwan. The demographic data, social support data, activities of daily living (ADL), resilience scale scores, and mental well-being scale scores of the participants were compared. There were no statistically significant differences in the participation rate, demographic data, and social support data between the three periods. The correlation analysis confirmed significant negative relationships between the number of COVID-19 cases and outpatient department visits per month (r = −0.764, p < 0.001), emergency department visits per month (r = −0.023, p < 0.001), ADL (r = −0.257, p = 0.03), resilience scale (r = −0.390, p < 0.001), and mental well-being scale (r = −0.475, p < 0.001). In conclusion, the severity of the COVID-19 outbreak in Taiwan was associated with declines in the ADL, mental well-being, and resilience of patients who sought medical attention.

Is non-operative management of acetabular fracture a viable option for older patients? A systematic review of the literature for indication, treatments, complications and outcome

There is no consensus about the best treatment for acetabular fracture in older patients. The purpose of this study was to review the current literature looking for indication, perioperative information and outcome of nonoperative management for acetabular fractures in elderly.A systematic review of literature was performed on different research database by using various combination of the keywords "acetabular fracture", "elderly patients", "60 years", "nonoperative", "nonsurgical" and "conservative treatment".Six articles met our inclusion criteria, 315 patients aged 60 or more treated nonoperatively for acetabular fracture were included in the analysis. The average age was 78.1 years, the average follow-up length was 48.7 months. The main criteria for indication of nonoperative management for acetabular fractures were, old age (75 years or more), two or more important medical comorbidities, and minimally or undisplaced fracture. The most frequent fracture pattern was anterior column in 25.3% of cases. Fall from standard height was the most frequent causative mechanism in 80% of patients. A conversion total hip arthroplasty was performed after 8.3% of cases. A 1-year mortality of 18% was reported, an overall mortality of 33.1% at last follow-up was reported.The management of acetabular fractur in elderly is a challenging problem and there is no consensus about the best treatment. Currently, multiple treatment options have been suggested, depending on fracture pattern and patients' general conditions. Although operatively treatment allow for an early recovery, there is not an high level of evidence about the superiority in terms or complications and mortality rate compared to nonoperative treatment.