Decreased Muscle Strength and Quality in Diabetes-Related Dementia

Background/Aims Diabetes-related dementia (DrD), a dementia subgroup associated with specific diabetes mellitus (DM)-related metabolic abnormalities, is clinically and pathophysiologically different from Alzheimer disease (AD) and vascular dementia. We determined whether skeletal muscle strength, quality, and mass decrease in individuals with DrD. Methods We evaluated grip and knee extension strength, muscle mass, and gait speed in 106 patients with probable AD and without type 2 DM (AD[-DM] group), 74 patients with probable AD and with DM (AD[+DM] group), and 36 patients with DrD (DrD group). Muscle quality was defined as the ratio of muscle strength to muscle mass. Results Both female and male subjects with DrD showed significantly decreased muscle strength and quality in the upper extremities compared with the subjects with AD[-DM] or AD[+DM]. Female subjects with DrD showed significantly decreased muscle quality in the lower extremities compared with the subjects with AD[-DM]. Both female and male subjects with DrD had a significantly lower gait speed compared with the subjects with AD[-DM]. However, there were no significant differences in muscle mass and the prevalence of sarcopenia between the groups. Conclusion Subjects with DrD showed decreased muscle strength and quality, but not muscle mass, and had a low gait speed.