GLP-1 receptor agonist therapy and skeletal muscle: A narrative review synthesizing adult evidence with implications for older adults.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing existing human studies without formal systematic review or meta-analysis
PubMed 42633386 · doi:10.1016/j.jarlif.2026.100083
What was done
This narrative review synthesized findings from 21 human studies evaluating the effects of glucagon-like peptide-1 receptor agonist (GLP-1-RA) therapy on skeletal muscle mass, volume, composition, strength, performance, and acute physiological responses, focusing on implications for older adults.
What was found
Most studies reported that GLP-1-RA therapy caused skeletal muscle mass loss, representing 8.5% to 24.5% of total weight loss. Muscle quality mostly improved through increased muscle density and decreased fat content. Muscle strength generally showed no significant change.
Why it matters
Highlights that while muscle mass loss accounts for up to a quarter of GLP-1-RA-induced weight reduction, muscle quality and strength appear preserved, though clinicians must carefully weigh frailty risks in older patients.
Limits
Only 4 of the 21 included studies specifically examined older adults, and these were methodologically heterogeneous and difficult to compare. Direct evidence is insufficient to determine whether older adults experience heightened vulnerability to muscle loss or clinical frailty complications. The review is narrative rather than systematic, with no quantitative meta-analysis reported in the abstract.
Cited by
- supports Using GLP-1 receptor agonists without adequate diet and exercise causes substantial loss of muscle mass alongside fat loss.