Relationship Between Age-Related Changes in Skeletal Muscle Mass and Physical Function: A Cross-Sectional Study of an Elderly Japanese Population

Relationship between Subjective Grip Strength and Physical Functioning among Community-Dwelling Older Women

This study investigated the relationship between subjective grip strength and physical function in community-dwelling older women. Subjective grip strength was assessed using a questionnaire, and physical function and body composition were compared between groups with strong and weak subjective grip strength. Additionally, the two groups were compared in those with mild cognitive impairment (MCI) and those with normal cognitive function, respectively. The results showed significant differences in grip strength (p < 0.001), 30 s chair-stand (CS-30) test (p = 0.039), timed up-and-go (TUG) test (p = 0.027), maximal gait speed (p = 0.029), and skeletal muscle mass (p < 0.001). Older adults with normal cognitive function showed significant differences in grip strength (p < 0.001), quadriceps muscle strength (p < 0.009), one-leg standing time (p = 0.041), CS-30 (p = 0.002), TUG (p = 0.014), gait speed (p = 0.006), and skeletal muscle mass (p = 0.003). Older adults with low subjective grip strength had lower physical function and skeletal muscle mass. However, no items showed significant differences between groups among older adults with MCI. Thus, subjective grip strength is an indicator of an overall decline in physical function and a reduction in skeletal muscle mass in older adults, and cognitive function should be considered when assessing subjective grip strength in older adults.

Skeletal Muscle Mass Index Reduction Rate as a Prognostic Indicator for Patients Undergoing Pancreatectomy for Pancreatic Cancer

Background/Aim

There have been many studies on skeletal muscle depletion before surgery, and skeletal muscle depletion is a known risk factor for poor prognosis. However, reports on the association between changes in skeletal muscle mass and prognosis after surgery for pancreatic cancer are very few.

Patients and Methods

The data of 137 patients who underwent pancreatectomy for pancreatic cancer between 2005 and 2022 were reviewed. Muscle areas were measured at the third lumbar vertebral level, and skeletal muscle mass index (SMI) reduction rates were calculated. Patients were divided into two groups using receiver operating characteristic (ROC) curve analysis based on the SMI reduction rate with a cutoff of 14% reduction rate. The clinicopathological factors, overall survival (OS), and recurrence-free survival (RFS) were compared between the two groups. Survival rates were analyzed both univariately and multivariately to clarify the factors associated with poor prognosis after pancreatectomy.

Results

A total of 102 patients met the inclusion criteria. SMI reduction rate ≥14% significantly correlated with advanced age and higher incidence of postoperative complications. In the multivariate Cox regression analysis, preoperative prognostic nutritional index (PNI) <40 and SMI reduction rate ≥14% were significantly associated with poor OS. Tumor size ≥3.0 cm, preoperative neutrophile-lymphocyte ratio ≥3.0, and SMI reduction rate ≥14% were significantly associated with poor RFS.

Conclusion

The rate of skeletal muscle mass reduction after pancreatic surgery is an independent prognostic factor for survival in patients with pancreatic cancer.

Prospective associations between changes in physical activity and sedentary time and subsequent lean muscle mass in older English adults: the EPIC-Norfolk cohort study

BACKGROUND

The longitudinal associations between physical behaviours and lean muscle mass indices need to be better understood to aid healthy ageing intervention development.

METHODS

We assessed physical behaviours (total physical activity, moderate-to-vigorous physical activity (MVPA), light physical activity, total sedentary time and prolonged sedentary bout time) for 7 days using hip-worn accelerometers. We also assessed domain-specific physical behaviours (walking, cycling, gardening and housework time) with self-report questionnaires at baseline (2006-2011) and follow-up (2012-2016) in the European Prospective Investigation into Cancer (EPIC)-Norfolk study. We assessed body composition using dual-energy X-ray absorptiometry (DEXA) at follow-up in 1535 participants (≥ 60 years at baseline). From this, we derived appendicular lean muscle mass (ALM) indices (% relative ALM = (ALM/total body weight)*100), body mass index (BMI)-scaled ALM (ALM/BMI, kg/kg/m2) and height-scaled ALM (ALM/height2, kg/m2)). We evaluated the prospective associations of both baseline and change in physical behaviours with follow-up muscle mass indices using multivariable linear regression.

RESULTS

Over 5.5 years (SD 14.8) follow-up, higher baseline accelerometer-measured physical activity and lower sedentary time were associated with higher subsequent relative ALM and BMI-scaled ALM, but not height-scaled ALM (e.g. 0.02% higher subsequent relative ALM per minute/day of baseline MVPA for men). Greater increases in physical activity and greater declines in sedentary time variables were associated with higher subsequent relative ALM and BMI-scaled ALM, but not height-scaled ALM (e.g. 0.001 kg/kg/m2 subsequent BMI-scaled ALM and 0.04% subsequent relative ALM per min/day/year increases in LPA over follow-up; 0.001 kg/kg/m2 subsequent BMI-scaled ALM and -0.03% subsequent relative ALM per min/day/year less of total sedentary time over follow-up). Greater increases in women's cycling and gardening over follow-up were associated with greater subsequent relative ALM (cycling 0.9% per hour/week/year; gardening 0.2% per hour/week/year) and BMI-scaled ALM (cycling 0.03 kg/kg/m2 per hour/week/year; gardening 0.004 kg/kg/m2 per hour/week/year).

CONCLUSION

Physical behaviours across all intensities, and in women more specifically cycling and gardening, may help prevent age-related declines in muscle mass.