Variability in muscle function deficits and clinical identification of sarcopenic obesity in older adults with type 2 diabetes

Introduction: Sarcopenic obesity (SO) is increasingly recognized as a major yet often overlooked complication in older adults—particularly those with type 2 diabetes (T2D)—and is linked to adverse events. SO evaluation requires muscle function tests [handgrip strength (HGS), knee extensor strength, chair-stand] and body composition. However, SO prevalence can vary widely depending on the muscle function test used, and these assessments are not routinely implemented in clinical care as they might be time-consuming. Aims: (1) Evaluate differences in the prevalence of altered muscle function using internationally accepted clinical guidelines among community-dwelling older adults with T2D; (2) to develop risk clusters for predicting increased SO probability; and (3) to develop an SO index based on routine clinical measures that differentiates individuals by their likelihood of having SO. Methods: Participants underwent comprehensive assessments of muscle function, including HGS, maximal knee extension strength, and chair stand test. Body composition was evaluated using bioelectrical impedance analysis to determine appendicular lean mass relative to body weight. Clinical data, including waist circumference, body mass index, prescription medications, metabolic markers, sex hormones, physical function tests, dietary intake, and physical activity, were collected using standardized protocols. Prevalence of altered muscle function and SO obesity was calculated using internationally accepted SO criteria. Results: Participated in the study 100 community dwelling older adults diagnosed with T2D (mean age: 69.75 ± 4.64). Altered muscle function prevalence ranged from 1% (HGS) to 92% (chair-stand). SO was present in 72% of the sample. Cluster analysis identified three SO severity groups: severe (N = 37), moderate (N = 32), and mild (N = 31). Significant differences in health, sex hormones, and physical function were noted across clusters. A SO risk index using five routine clinical measures (waist circumference, body mass index, medication count, HbA1c, and chair stand) effectively distinguished SO risk clusters (AUC = 0.87). Conclusion: Among older adults with T2D, SO was prevalent, with substantial impairments in muscle function and body composition. Disease severity was primarily driven by alterations in appendicular lean mass and lower-limb strength, whereas handgrip strength showed limited discriminatory capacity. These findings highlight the importance of comprehensive functional and body composition assessment for older adults with T2D. Clinical trial registration: clinicaltrials.gov, identifier: NCT03560375.