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

Lower body muscle strength, dynapenic obesity and risk of type 2 diabetes -longitudinal results on the chair-stand test from the Survey of Health, Ageing and Retirement in Europe (SHARE)

BACKGROUND

The chair-stand test is a measure of lower body muscle strength. In a longitudinal study with older adults, we investigated whether results of the five-repetition chair-stand test (CST-5) are associated with incident type 2 diabetes, and whether diabetes risk in obese persons is modified by dynapenia (age-related loss of muscle strength) in the lower limbs.

METHODS

We used data of the Survey of Health, Ageing and Retirement in Europe (SHARE), a panel study with eight waves carried out between 2004 and 2020 in 28 European countries and Israel mainly in persons aged 50 years or older. Forty-six thousand one hundred nineteen persons (mean age 63.5 years, 44.1% men) with CST-5 data and follow-up data for diabetes were included from wave 2 and waves 4 to 7. The mean follow-up time was 5.3 years (standard deviation 2.9 years). Relative risks with 95% confidence intervals (CI) were estimated from log-linear models with a Poisson working likelihood and robust standard errors.

RESULTS

In the crude model, increased risks of diabetes were found for persons who considered the CST-5 as not safe, or whose times for the test were in the highest or second highest quartiles (relative risks 2.18 (95% CI: 1.95-2.43), 1.71 (1.54-1.91), 1.44 (95% CI: 1.29-1.61), reference: lowest quartile). These associations were attenuated in the fully adjusted regression model (relative risks 1.32 (95% CI: 1.17-1.48), 1.23 (1.10-1.37), 1.19 (1.06-1.33)). Furthermore, in fully adjusted models, the risk of diabetes in obese persons did not depend on whether they had low muscle strength or not. In obese persons with times for 5 sits and stands > 15 seconds, the adjusted risk of diabetes was 2.56 (95% CI: 2.22-2.95) times higher than in non-obese persons with times ≤15 seconds. The corresponding relative risk in obese persons with times ≤15 seconds was 2.45 (2.25-2.67).

CONCLUSIONS

Poor results in the CST-5 were associated with an increased risk of diabetes. Among obese persons, the risk of diabetes was not modified by results of the CST-5.

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.