Conclusion

This narrative review primarily synthesizes evidence from general adult populations, as direct evidence on GLP-1-RA effects on skeletal muscle in older adults remains extremely limited, with only four of the 21 included studies specifically examining adults aged ≥65. The available evidence summarized in this narrative review suggests that GLP-1-RA therapy can be accompanied by skeletal muscle loss in some contexts, although findings may vary by population characteristics, drug and dosing, treatment duration, and measurement method, with several studies reporting preserved strength and muscle mass or improvements in muscle quality. Evidence for older adults specifically remains extremely limited, and the findings of this review are drawn predominantly from general adult populations with implications extrapolated to older adults. While the available data do not conclusively show which unique muscular effects of GLP-1-RAs exist in older adults, they indicate a pattern of potentially increased vulnerability to sarcopenia and frailty in this population. Due to a high baseline risk of sarcopenia, even modest muscle loss may carry greater functional consequences in older populations.

Given these findings, the widespread and expanding use of GLP-1-RAs suggests that clinicians should be aware of their effects on skeletal muscle mass and exercise caution in prescribing these medications for older adults. Clinicians should be proactive with patients to mitigate potential adverse outcomes by monitoring muscle health, recommending aerobic and resistance exercise training, and ensuring adequate protein and micronutrient intake. Ultimately, recognizing muscle health as a therapeutic priority is an important step toward safe and holistic patient care during GLP-1-RA treatment.