Associations Between Relative Grip Strength and the Risk of 15 Cancer Sites

Association of alpha-actinin-3 genotype with muscle mass and physical function in community-dwelling older adults

PURPOSE

Polymorphisms (rs1815739; R577X) in the gene encoding alpha-actinin-3 (ACTN3) are thought to be associated with body composition and physical function in older people and athletes. RR homozygotes are associated with greater expression of ACTN3 protein in muscle than the X-allele carriers. We aimed to investigate the association between ACTN3 R577X polymorphism and appendicular skeletal muscle mass, walking speed, and muscle strength in older adults.

METHODS

A cross-sectional analysis was performed on 265 community-dwelling older adults (mean age 74.0 ± 5.8 years, 63.4% female) who provided data on ACTN3 gene polymorphisms and completed surveys in the Tarumizu study conducted between 2018 and 2019. Genetic polymorphisms were categorized as RR homozygous and X allele. Muscle mass was assessed using the appendicular skeletal muscle mass index (ASMI), and physical function was assessed based on walking speed and relative muscle strength. Those in the bottom 25% for each sex were considered "low" and the association with ACTN3 genotype was examined.

RESULTS

Considering ACTN3 polymorphism, 72 participants were RR homozygotes (27.2%) and 193 were X-allele carriers (72.8%). After adjusting for potential confounders, RR homozygosity was associated with not having low muscle mass (odds ratio 0.39, 95% confidence interval 0.19-0.82, p = 0.013) but not with low walking speed and muscle strength.

CONCLUSION

The association between ACTN3 genotype and physical function in community-dwelling older adults is not clear; however, it is considered to be associated with muscle mass.

Preoperative low absolute and relative handgrip strength as predictors of postoperative short-term outcomes: a prospective study based on patients aged 60 years and older with gastric cancer

PURPOSE

This study aimed to determine the association of absolute and relative HGS indicators with postoperative short-term outcomes in older patients with gastric cancer.

METHODS

The prospective, single-center, observational study involved 230 patients (age ≥ 60 years) who underwent radical gastrectomy. Absolute HGS was directly obtained from results measured by a hand dynamometer, while relative HGS was calculated as the value of absolute HGS divided by body mass index (BMI), appendicular skeletal muscle mass index (ASMI) and age, respectively. Low absolute HGS was defined according to the criterion in AWGS 2019 consensus and the first gender-specific quartile. Low relative handgrip strength was defined if it was below the first gender-specific quartile of the distribution. Postoperative outcomes included total complications, malnutrition and length of hospital stay. Univariate and multivariate regression models were performed to investigate and compare the predictive values of different HGS indicators.

RESULTS

For the five HGS indicators, multivariate analyses showed that low absolute HGS (AWGS consensus), low HGS/BMI and HGS/age were independent risk factors for both postoperative total complications (absolute HGS(AWGS consensus): OR  2.03, 95%CI:1.05-3.93; HGS/BMI: OR  2.12, 95%CI 1.05-4.28; HGS/age: OR  2.79, 95%CI 1.40-5.54) and malnutrition (absolute HGS(AWGS consensus): OR   2.01, 95%CI 1.10-3.67; HGS/BMI: OR  2.28, 95%CI 1.20-4.33; HGS/age: OR   2.70, 95%CI 1.42-5.14). Low absolute HGS (quartile) was an independent risk factor for malnutrition (OR   1.96, 95%CI 1.04-3.71). Moreover, Low HGS/age was associated with lengthened postoperative hospital stay (OR  2.07, 95%CI 1.12-3.85).

CONCLUSIONS

Except HGS/ASMI, both absolute and relative HGS indicators were associated with postoperative short-term outcomes. Particularly, HGS/age revealed relatively better predictive value for the studied outcomes.

Longitudinal association of handgrip strength with all-cause and cardiovascular mortality in older adults using a causal framework

To date, there is no study addressing the time-varying confounding bias in the association of handgrip strength (HGS) with all-cause or cardiovascular mortality. Therefore, we conducted marginal structural models (MSM) to provide causal estimations on the associations of HGS with all-cause and cardiovascular mortality in a representative sample of adults aged 50 years or older. Data from 29 countries including 121,116 participants (276,994 observations; mean age 63.7 years; 56.3 % women) free from prior heart attack or stroke were retrieved from consecutive waves of the Survey of Health, Ageing and Retirement in Europe (SHARE). During a median of 7.7 years follow-up (interquartile range 3.8-11.8) and 1,009,862 person-years, 6407 participants (5.3 %) died due to all causes, and 2263 (1.9 %) died due to cardiovascular diseases. Using repeated measures of handheld dynamometry, we determined absolute and relative to body mass index HGS of each participant. We applied adjusted MSM to estimate hazard ratios (HRs) associated with changes over time in HGS addressing the time-varying confounding bias. An increase of 5 kg in HGS was associated with a reduced risk of all-cause [HR 0.86, 95 % confidence interval (CI), 0.86-0.90], overall cardiovascular (HR 0.86, 95 % CI 0.82-0.86), heart attack (HR 0.90, 95 % CI 0.86-0.95), and stroke (HR 0.86, 95 % CI 0.82-0.90) mortality. The associations of relative HGS were of stronger magnitude in all cases. Our findings provide critical evidence on the importance of increasing general muscle strength in older adults to reduce mortality risk, particularly concerning cardiovascular causes.

Associations between childhood and adulthood socioeconomic position and grip strength at age 46 years: findings from the 1970 British Cohort Study

BACKGROUND

Muscle weakness is a key criterion for important age-related conditions, including sarcopenia and frailty. Research suggests lower childhood socioeconomic position (SEP) may be associated with muscle weakness in later life but there is little evidence on associations in younger adults closer to peak muscle strength. We aimed to examine relationships between indicators of SEP in childhood and adulthood and grip strength at age 46y.

METHODS

We examined 7,617 participants from the 1970 British Cohort Study with grip strength measurements at 46y. We used sex-specific linear regression models to test associations between five different indicators of SEP in childhood and adulthood (paternal occupational class and parental education levels at age 5 and own occupational class and education level at age 46) and maximum grip strength. Models were adjusted for birth weight, BMI in childhood and adulthood, adult height, disability in childhood, leisure-time physical activity in childhood and adulthood, sedentary behaviour in childhood and adulthood, occupational activity and smoking at age 46.

RESULTS

Among women, lower SEP in childhood and adulthood was associated with weaker grip strength even after adjustments for covariates. For example, in fully-adjusted models, women whose mothers had no qualifications at age five had mean grip strength 0.99 kg (95% CI: -1.65, -0.33) lower than women whose mothers were educated to degree and higher. Among men, lower levels of father's education and both adult SEP indicators were associated with stronger grip. The association between own occupational class and grip strength deviated from linearity; men in skilled-manual occupations (i.e. the middle occupational group) had stronger grip than men in the highest occupational group (Difference in means: 1.33 kg (0.60, 2.06)) whereas there was no difference in grip strength between the highest and lowest occupational groups. Adjustment for occupational activity largely attenuated these associations.

CONCLUSION

Findings highlight the need to identify age and sex-specific interventions across life to tackle inequalities in important age-related conditions related to weakness.

Predictive value of preoperative handgrip strength on postoperative outcomes in patients with gastrointestinal tumors: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to explore the predictive value of preoperative handgrip strength on postoperative outcomes in patients with gastrointestinal tumors.

METHODS

Databases including Cochrane Library, Pubmed, Embase, Web of Science, and CINAHL Complete were searched for articles published from the establishment of database until August 7, 2021. Two researchers independently screened the literature, extracted the data, and evaluated the quality.

RESULTS

Eight studies were included, involving five prospective and three retrospective cohort studies with 2291 participants. The prevalence of preoperative low handgrip strength ranged from 11.8 to 62.7%. Preoperative low handgrip strength was associated with an increased risk of total complications (OR = 2.23, 95%CI = 1.43-3.50), pneumonia (OR = 5.16, 95%CI = 3.17-8.38), ileus (OR = 2.48, 95%CI = 1.09-5.65), and short-term mortality (OR = 7.28, 95%CI = 1.90-27.92).

CONCLUSION

This systematic review and meta-analysis indicated that preoperative HGS had important value to predict certain adverse postoperative outcomes among patients with GI tumors. Low handgrip strength criteria, definition of total complications, and country are the potential sources of heterogeneity, and more research are required to test and update these results.