Hand grip strength as a physical biomarker of aging from the perspective of a Fibonacci mathematical modeling

Test-retest reliability of Latin American Group for Maturity (GDLAM) protocol in older women

Functional autonomy (FA) is a critical factor in determining the quality of life of older adults (OA), especially in the case of older women (OW), as they face a decline in FA in their later years of life. FA should be assessed early, using valid, reliable, and low-cost tests. This study evaluated the test-retest reliability of GDLAM and GDLAM autonomy index (GI) in OW. Thirty-nine OW (71.2 ± 6.50 years) participated in the study. A repeated measures design was used to compare the interday test-retest reliability of the five GDLAM tests (seconds) and the GI (points). The five tests represent activities of daily living, such as dressing or wandering around the house, while the GI provides a weighting of the results of the five tests. The analysis consisted of the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and coefficient of variation (CV). A CV ≤ 10% and an ICC ≥ 0.80 were considered acceptable reliability, whereas a CV ≤ 5% and an ICC ≥ 0.90 were considered high reliability. The outcome of the five tests, represented by the GI, showed high interday test-retest reliability (CV = 6.00% and ICC = 0.91). The results of this study demonstrate that the five tests of the GDLAM protocol and the GI have high interday test-retest reliability and good interday reproducibility. From a practical point of view, the GDLAM protocol allows the assessment of FA of community-dwelling OW, providing background for early diagnosis and, with it, the possibility of developing an individualized physical exercise prescription.

Progress in the study of aging marker criteria in human populations

The use of human aging markers, which are physiological, biochemical and molecular indicators of structural or functional degeneration associated with aging, is the fundamental basis of individualized aging assessments. Identifying methods for selecting markers has become a primary and vital aspect of aging research. However, there is no clear consensus or uniform principle on the criteria for screening aging markers. Therefore, we combine previous research from our center and summarize the criteria for screening aging markers in previous population studies, which are discussed in three aspects: functional perspective, operational implementation perspective and methodological perspective. Finally, an evaluation framework has been established, and the criteria are categorized into three levels based on their importance, which can help assess the extent to which a candidate biomarker may be feasible, valid, and useful for a specific use context.

Handgrip strength and upper limb functional performance measures in people over 18 years old: Analysis of relationships and influencing factors

BACKGROUND

Handgrip strength is a common, simple, and inexpensive method to measure muscle strength. On the other hand, the functional performance measurement involves a usual task which implies repeating elements between the individuals' interaction and the environment. This is fundamental for projecting their results to daily life situation.

PURPOSE

To explore the relationship between grip strength and measures of functional performance of the upper limbs (ULs) in people over 18 years of age, and to determine the influence of sociodemographic and anthropometric variables on the relationship.

STUDY DESIGN

A cross-sectional study was conducted under the analytical empirical approach, using linear associations between handgrip strength and functional performance measurement tests (correspondence analysis).

METHODS

Three hundred sixty-two male and female individuals between 18 and 91 years of age from 4 Colombian cities participated. The grip strength of both ULs measured with a digital dynamometry was associated with the Box and Block Test (BBT, manual dexterity), Nine-Hole Peg Test (NHPT, daily living tasks), and Jebsen-Taylor Hand Function Test (JJT, ability to grasp, pick up, and place). Multiple linear regression analyzes were performed to assess possible explanatory factors of a sociodemographic and anthropometric order.

RESULTS

A significant association was found between the grip strength of dominant and non-dominant ULs with all functional performance tests (ρ > 0.27 and p < .001), except for the writing and simulated feeding subtests of the JJT (ρ ≤ 0.16). An interactive effect of age was found in the relationship between grip strength and the 3 functional performance tests.

CONCLUSIONS

These results support the association between grip strength with the NHPT, JJT, and BBT measures and the interactive effect of age on the performance of all tests.

Effect of the Active Aging-in-Place-Rehabilitation Nursing Program: A Randomized Controlled Trial

(1) Background: It is of great importance to promote functional capacity and positive lifestyles, since they contribute to preventing the progression of frailty among the older adults. The aim of this study was to evaluate the effect of active aging-in-place−rehabilitation nursing program (AAP-RNP) on the functional capacity and lifestyles of frail older adults. (2) Methods: This was a single-blinded, two-group, randomized, controlled trial of 30 frail older people enrolled at a Health-care unit in Portugal between 2021 and 2022. The duration of the program was 12 weeks, and the sessions took place at the participants’ homes. We used as instruments the Tilburg Frailty Indicator; Fried frailty phenotype; Senior Fitness Test battery; Barthel Index; Lawton Index; handgrip strength measurement; Tinetti Index; Individual lifestyle profile; and Borg’s perception of effort. (3) Results: Post-program, there was an improvement in multidimensional and physical frailty, functional capacity, balance, and perceived exertion (p < 0.05) in the experimental group. Among the older adults’ lifestyles, we observed significant improvements in physical activity habits, relational behavior, and stress management. (4) Conclusions: Rehabilitation nurses have a relevant role, and the AAP-RNP seems to be effective in improving functional capacity and lifestyles in frail older adults.

The Effects of Yoga Exercise on Blood Pressure and Hand Grip Strength in Chronic Stroke Patients: A Pilot Controlled Study

BACKGROUND

We investigated the beneficial effect of add-on yoga with rehabilitation on blood pressure (BP) and hand grip strength in patients with chronic stroke (more than 90 days).

METHODS

The study included patients 30-80 years of age who could stand independently for 1 min. Patients with psychiatric diseases or undergoing other therapies (like acupuncture) were excluded. The yoga group received training (1 h session twice weekly) with standard rehabilitation for 8 weeks. The control group received standard rehabilitation only. There were no differences in age, gender, hand grip strength, or BP between the two groups (16 subjects in each group) at baseline.

RESULTS

The systolic BP (p = 0.01) decreased significantly, and the diastolic BP also decreased but not significantly in the yoga group (p = 0.11). For hand grip strength, both the unaffected hand (p = 0.00025) and the affected hand (p = 0.027) improved significantly. The control group showed no significant change in systolic or diastolic BP, nor did the grip strength change in both hands. Gender and age also affected the results of overall rehabilitation in that women benefited more from a decrease in BP, while men and young people (lower than the mean age of 60) benefited from hand grip strength improvement.

CONCLUSIONS

Combining yoga with rehabilitation in chronic stroke patients can improve hand grip strength and decrease systolic BP.

Association between Handgrip Strength and the Systemic Immune-Inflammation Index: A Nationwide Study, NHANES 2011-2014

(1) Background: The Systemic immune-inflammatory index (SII) has been proven to be an effective biomarker of human immune and inflammatory levels and has prognostic significance for most diseases. Handgrip strength (HGS) is a simple and low-cost strength measurement method, which is not only highly correlated with overall muscle strength but also accurately and reliably predicts the risk of multiple chronic diseases and mortality; (2) Purpose: Association between HGS and the SII is unclear. The purpose of this study was to investigate the association between HGS and the SII in American adults; (3) Methods: We used the data from the 2011-2012 and 2013-2014 cycles of the National Health and Nutrition Examination Survey (NHANES), involving a total of 8232 American adults (aged 18-80 years). The SII was calculated as the Platelet count × Neutrophil count/Lymphocyte count; HGS was recorded as the ratio of the sum of the highest grip-strength values of each hand to body mass index taken as the relative grip strength. A weighted generalized linear regression model and analysis of restricted cubic spline regression, adjusted for confounding factors, were used in this study to assess associations between HGS and the SII in American adults; (4) Results: There was a negative correlation between the HGS and the SII of different sexes (p < 0.05), and there was a significant negative nonlinear relationship between the HGS and the SII in males (p for nonlinear = 0.0035), and the SII showed a downward trend with the increase in the HGS in males (Q2: β = -61.03, p = 0.01; Q3: β = -61.28, p = 0.04, Q4: β = -64.36, p = 0.03, p for trend = 0.04), when the HGS exceeds 3.16, with the HGS increasing, the downward trend of increasing the SII slowed down. The nonlinear relationship between the HGS and the SII in females was not significant (p for nonlinear = 0.1011), and the SII showed a linear downward trend with the increase in the HGS (Q2: β = -24.91, p = 0.25; Q3: β = -62.01, p = 0.03, Q4: β = -74.94, p = 0.03, p for trend = 0.01); (5) Conclusions: HGS is inversely and independently associated with SII levels, and although the limited cubic spline regression analysis showed gender differences, the overall trend of the HGS and the SII in different genders was consistent, with both showing that the SII decreased with increasing the HGS. In addition, HGS has high general applicability based on its ease of measurement; it is possible to understand one's own grip-strength level through routine grip-strength tests, and to make preliminary predictions on the current level of immunity and inflammation in the body.

Combined driving: task-specific position impacts grip strength of equestrian athletes

Background

Loss of hand strength is a predictor of mortality in aging populations. Despite reliance on the hands to participate in equestrian driving activity, no existing studies focus on associations of hand strength to athletic performance. Therefore, this study 1) established baseline handgrip of equestrian combined drivers in standing and task-specific positions, 2) determined endurance of task-specific handgrip, 3) compared handgrip strength to normative data, and 4) evaluated associations of handgrip and equestrian-specific variables.

Methods

There were 51 combined drivers (9 males, 42 females) ages 21–78 who completed a survey, standing handgrip, and grip strength and endurance in a task-specific position. Sixty-three percent of participants were 50 years or older. The dynamometer grip bar was normalized by hand size for standing tests; to duplicate sport-specific tasks, the bar was set to the closest setting. Significances were determined at p < 0.05.

Results

Drivers with more than 30 years of experience demonstrated highest summed standing (73.1 ± 5.2 kg) and summed sitting (59.9 ± 6.3 kg) grip strength. Females 60-years and older had greater handgrip endurance (Χ² = 8.323, df = 2, p = .0156) in non-dominant (left) hands. Males (60%) reported more cold weather fatigue than females. Glove wearing was associated with bilateral endurance balance; a higher proportion of endurance balance between dominant and non-dominant (49% high-high and 29% low-low; Χ² = 11.047, df = 1, p = .0009) was realized. There were no associations of handgrip and prior injury.

Conclusions

Our results have implications in understanding task-specific and normative grip strengths in aging equestrian populations. Bilateral balance in handgrip strength and endurance is important particularly in maintaining strength in non-dominant hands over time. Equestrian driving sport promotes greater endurance in older females. Strength can be improved by participating in combined driving, and engagement in this sport over several years’ benefits hand strength over time. This cohort of equestrian participants provides evidence that participating in hand-specific activities promotes greater strength, which has been previously shown to improve aging outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11556-021-00282-w.

Cancer treatment-induced NAD+ depletion in premature senescence and late cardiovascular complications

Numerous studies have revealed the critical role of premature senescence induced by various cancer treatment modalities in the pathogenesis of aging-related diseases. Senescence-associated secretory phenotype (SASP) can be induced by telomere dysfunction. Telomeric DNA damage response induced by some cancer treatments can persist for months, possibly accounting for long-term sequelae of cancer treatments. Telomeric DNA damage-induced mitochondrial dysfunction and increased reactive oxygen species production are hallmarks of premature senescence. Recently, we reported that the nucleus-mitochondria positive feedback loop formed by p90 ribosomal S6 kinase (p90RSK) and phosphorylation of S496 on ERK5 (a unique member of the mitogen-activated protein kinase family that is not only a kinase but also a transcriptional co-activator) were vital signaling events that played crucial roles in linking mitochondrial dysfunction, nuclear telomere dysfunction, persistent SASP induction, and atherosclerosis. In this review, we will discuss the role of NAD⁺ depletion in instigating SASP and its downstream signaling and regulatory mechanisms that lead to the premature onset of atherosclerotic cardiovascular diseases in cancer survivors.

Handgrip strength, dynapenia, and related factors in postmenopausal women

OBJECTIVE

This study aimed to evaluate the prevalence of dynapenia and factors related to low dominant handgrip strength (HGS) in postmenopausal women.

METHODS

A cross-sectional study was performed on 249 postmenopausal women aged 50 to 84 years. The following variables were recorded: age, age at menopause, smoking status, and the HGS measured with a digital dynamometer, body mass index, and adiposity assessed by bioelectric impedance. The physical activity level was evaluated by using the International Physical Activity Questionnaire. Bone mineral density was reported as T-scores, and blood biochemical parameters (calcium, phosphorus, vitamin D, and parathormone levels) were measured.

RESULTS

31.3% of women had dynapenia, and those aged ≥65 years had lower HGS (P < 0.001). Age at menopause was also associated with HGS, with those with menopause < 51 showing lower HGS (P = 0.005). Likewise, fat content ≥ 40%, and osteopenia/osteoporosis were also related to lower strength (P < 0.001). There was no statistically significant difference among HGS with respect to body mass index, smoking status, and plasma levels of vitamin D. A logistic regression model with lower Akaine Information Criterion showed that for every year in age and for each 1% of adiposity, women were more likely to have dynapenia with odd ratio (OR): 1.09; 95% and confidence interval (CI): 1.04 to 1.14 and OR: 1.06; 95% CI: 1.00 to 1.13, respectively. Conversely, women with higher femoral neck T-score were less likely to have dynapenia (OR: 0.53; 95% CI: 0.35-0.78).

CONCLUSIONS

HGS was associated with age at menopause, bone mineral density, and adiposity adjusted by age. The age and adiposity were significantly associated with a higher risk of dynapenia, whereas women with higher femoral neck T-score were less likely to have dynapenia.

Effects of the association between APOE rs405509 polymorphisms and gene-environment interactions on hand grip strength among middle-aged and elderly people in a rural population in southern China

Background

Hand grip strength is a complex phenotype. The current study aimed to identify the effects of the association between APOE rs405509 polymorphisms and gene-environment interactions on hand grip strength among middle-aged and elderly people in a rural population in Gongcheng, southern China.

Methods

APOE rs405509 polymorphisms in 1724 participants (695 men and 1029 women, aged 45–97 years old) were genotyped using the Sequenom MassARRAY platform. Statistical analysis was conducted using SPSS 21.0 and Plink 1.90.

Results

The APOE rs405509 G allele was associated with lower hand grip strength in all participants (β = −1.04, P value <0.001), and the correlation seemed to be even stronger among women. A significant gene-environment interaction was observed between APOE rs405509 and smoking, especially in men. The hand grip strength of male smokers carrying the GG genotype was significantly higher than that of nonsmokers (P value = 0.004).

Conclusions

APOE rs405509 polymorphisms might be genetic factors that affect hand grip strength in a rural population in Gongcheng, southern China. The APOE rs405509-smoking interaction has an impact on hand grip strength.

Comparison of field- and laboratory-based estimates of muscle quality index between octogenarians and young older adults: an observational study

Muscle quality (the ratio of strength to lean muscle mass) might be a better indicator of muscle function than strength alone. Differences in muscle quality index (MQI) between octogenarians and young older adults remain unclear. The aims of the present cross-sectional study were to compare (1) MQI between octogenarians and young older adults, (2) lab versus field-based MQI tools, and (3) determine possible confounding factors affecting MQI in older adults. Compiled data from two cross-sectional studies included 175 younger and older adults (31 men and 144 women) with a mean age of 75.93±9.49 years. Participants with age ≥80 years old were defined as octogenarians (n=79) and <80 years was defined as young older adults (n=96). Laboratory MQI was derived from the ratio of grip strength to arm muscle mass (in kg) measured by dual-energy x-ray absorptiometry. Field-based MQI was quantified from the ratio of grip strength to body mass index (BMI). Octogenarians displayed lower field (P=0.003) and laboratory MQI (P<0.001) as compared with young older adults. There was a strong correlation effect between field MQI and laboratory MQI (P=0.001, R=0.85). BMI (P=0.001), and diabetes mellitus (P=0.001) negatively affected MQI. Women presented lower MQI (P=0.001) values than men. In light of this information, rehabilitation specialists should consider the use of field-based MQI as a tool for evaluation and follow-up of older population.

Relationship between smoking status and muscle strength in the United States older adults

OBJECTIVES

Muscle strength in older adults is associated with greater physical ability. Identifying interventions to maintain muscle strength can therefore improve quality of life. The purpose of this study was to evaluate whether current or former smoking status is associated with a decrease in muscle strength in older adults.

METHODS

Data from the Health and Retirement Study from 2012-2014 were analyzed with regard to maximum dominant hand grip strength, maximum overall hand grip strength, and smoking status (current, former, or never). Unadjusted linear regression was conducted. Other factors known to be related to strength were included in the adjusted linear regression analyses.

RESULTS

For maximum grip strength, the regression coefficient was 4.91 for current smoking (standard error [SE], 0.58; p<0.001), 3.58 for former smoking (SE, 0.43; p<0.001), and 28.12 for never smoking (SE, 0.34). Fully adjusted linear regression on the relationship between dominant hand grip strength and smoking did not yield a significant result. The factors significantly associated with dominant hand grip strength were male sex, younger age, a race/ethnicity of non-Hispanic White or non-Hispanic Black, higher income, morbidity of ≤1 condition, no pain, and moderate or vigorous exercise more than once a week.

CONCLUSIONS

Muscle strength in older adults was not associated with smoking status in the adjusted analysis.

Hand grip strength variability during serial testing as an entropic biomarker of aging: a Poincaré plot analysis

Background

The Poincaré plot method can be used for both qualitative and quantitative assessment of self-similarity in usually periodic functions, hence the idea of applying it to the study of homeostasis of living organisms. From the analysis of numerous scientific data, it can be concluded that hand functionality can be correlated with the state of the human body as a biological system exposed to various forms of ontogenetic stress.

Methods

We used the Poincaré plot method to analyze the variability of hand grip strength (HGS), as an entropic biomarker of aging, during 60 repetitive tests of the dominant and nondominant hand, in young and older healthy subjects. An observational cross-sectional study was performed on 80 young adults (18–22 years old, mean age 20.01 years) and 80 older people (65–69 years old, mean age 67.13 years), with a sex ratio of 1:1 for both groups. For statistical analysis, we applied univariate descriptive statistics and inferential statistics (Shapiro–Wilk test, Mann–Whitney U-test for independent large samples, with the determination of the effect size coefficient r, and simple linear regression. We calculated the effect of fatigue and the Poincaré indices SD₁, SD₂, SD₁/SD₂ and the area of the fitting ellipse (AFE) for the test values of each subject.

Results

The analysis of the differences between groups revealed statistically significant results for most HGS-derived indices (p ≤ 0.05), and the magnitude of the differences indicated, in most situations, a large effect size (r > 0.5). Our results demonstrate that the proposed repetitive HGS testing indicates relevant differences between young and older healthy subjects. Through the mathematical modeling of data and the application of the concept of entropy, we provide arguments supporting this new design of HGS testing.

Conclusions

Our results indicate that the variability of HGS during serial testing, which reflects complex repetitive biomechanical functions, represents an efficient indicator for differentiation between young and older hand function patterns from an entropic perspective. In practical terms, the variability of HGS, evaluated by the new serial testing design, can be considered an attractive and relatively simple biomarker to use for gerontological studies.

Grip Strength: An Indispensable Biomarker For Older Adults

Grip strength has been proposed as a biomarker. Supporting this proposition, evidence is provided herein that shows grip strength is largely consistent as an explanator of concurrent overall strength, upper limb function, bone mineral density, fractures, falls, malnutrition, cognitive impairment, depression, sleep problems, diabetes, multimorbidity, and quality of life. Evidence is also provided for a predictive link between grip strength and all-cause and disease-specific mortality, future function, bone mineral density, fractures, cognition and depression, and problems associated with hospitalization. Consequently, the routine use of grip strength can be recommended as a stand-alone measurement or as a component of a small battery of measurements for identifying older adults at risk of poor health status.