PURPOSE OF REVIEW: Obesity pharmacotherapy has become increasingly relevant in older adults due to challenges in lifestyle modification and the burden of non-communicable diseases. Despite the expanding use of anti-obesity medications (AOMs), sarcopenia and sarcopenic obesity (SO) remain major concerns in this population. This review synthesizes current evidence on glucagon-like peptide-1 receptor agonists (GLP-1 RAs), a well-studied AOMs, focusing on their effects on sarcopenia through mechanistic insights and clinical considerations in older adults.
RECENT FINDINGS: GLP-1 RAs effectively induce weight loss; however, concomitant muscle mass loss is common, raising concerns about sarcopenia. Weight cycling introduces uncertainty regarding skeletal muscle health and SO risk. Although data on muscle mass indices and physical performance remain limited and inconsistent, evidence suggests favorable effects on muscle metabolism and composition. Mechanistically, these effects are linked to GLP-1 RA-mediated suppression of inflammatory pathways, modulation of skeletal muscle metabolism, and preservation of mitochondrial function, thereby influencing insulin resistance. The most common adverse events are mild to moderate gastrointestinal symptoms, which may be mitigated through dietary counseling during dose escalation. Integrating GLP-1 RA therapy with tailored resistance exercise and caloric restriction with dietary counseling, including adequate protein intake (1.2-1.6 g/kg/day), may help preserve muscle mass and function in older adults. Implementation of GLP-1 RA-specific medical nutrition therapy protocols, with dietitian involvement to optimize dietary recommendations and manage adverse events, is recommended. Studies addressing skeletal muscle quantity, quality, and functional capacity are needed to clarify the effects of GLP-1 RAs on sarcopenic obesity in older adults.
