OBJECTIVE. Older people with type 2 diabetes are at high risk of mobility disability. We investigated the association of diabetes with lower-limb muscle mass and muscle quality to verify whether diabetes-related muscle impairments mediate the association between diabetes and low walking speed. RESEARCH DESIGN AND METHODS. Cross-sectional analysis of 835 participants (65 years and older) enrolled in the InCHIANTI population-based study. Total, muscular, and fat cross-sectional areas of the calf and relative muscle density were measured using peripheral quantitative computerized tomography. Indicators of muscle performance included knee extension torque, ankle plantar flexion and dorsiflexion strength, lower extremity muscle power, and ankle muscle quality (ratio of ankle strength to the muscle area, Kg/cm2). Gait performance was assessed by 4-m and 400-m walking speed. Diabetes was ascertained by standard American Diabetes Association criteria. RESULTS. Prevalence of diabetes was 11.4%. After adjustment for age and gender, participants with diabetes, had lower muscle density, knee and ankle strength, muscle power and worse muscle quality (all p<0.05). Diabetic participants were also slower on both 4-meter (beta coeff.:-0.115±0.024 m/s, p<0.001) and 400-meter (beta coeff.:-0.053±0.023 m/s, p<0.05) walking test. In multivariable linear regression models, lower-limb muscle characteristics accounted for 24.3% and 15.1% of walking speed difference comparing diabetic and nondiabetic subjects in the 4-meter and 400-meter walks, respectively. CONCLUSIONS. In older persons, diabetes is associated with reduced muscle strength and worse muscle quality. These impairments are important contributors of walking limitations related to diabetes.
Role of Muscle Mass and Muscle Quality in the Association Between Diabetes and Gait Speed
VOLPATO, Stefano;BIANCHI, Lara;ZULIANI, Giovanni;
2012
Abstract
OBJECTIVE. Older people with type 2 diabetes are at high risk of mobility disability. We investigated the association of diabetes with lower-limb muscle mass and muscle quality to verify whether diabetes-related muscle impairments mediate the association between diabetes and low walking speed. RESEARCH DESIGN AND METHODS. Cross-sectional analysis of 835 participants (65 years and older) enrolled in the InCHIANTI population-based study. Total, muscular, and fat cross-sectional areas of the calf and relative muscle density were measured using peripheral quantitative computerized tomography. Indicators of muscle performance included knee extension torque, ankle plantar flexion and dorsiflexion strength, lower extremity muscle power, and ankle muscle quality (ratio of ankle strength to the muscle area, Kg/cm2). Gait performance was assessed by 4-m and 400-m walking speed. Diabetes was ascertained by standard American Diabetes Association criteria. RESULTS. Prevalence of diabetes was 11.4%. After adjustment for age and gender, participants with diabetes, had lower muscle density, knee and ankle strength, muscle power and worse muscle quality (all p<0.05). Diabetic participants were also slower on both 4-meter (beta coeff.:-0.115±0.024 m/s, p<0.001) and 400-meter (beta coeff.:-0.053±0.023 m/s, p<0.05) walking test. In multivariable linear regression models, lower-limb muscle characteristics accounted for 24.3% and 15.1% of walking speed difference comparing diabetic and nondiabetic subjects in the 4-meter and 400-meter walks, respectively. CONCLUSIONS. In older persons, diabetes is associated with reduced muscle strength and worse muscle quality. These impairments are important contributors of walking limitations related to diabetes.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
