Does Hormone Therapy Affect Muscle Mass in Postmenopausal Women?
Despite previous suggestions that hormone therapy (HT) use protects against age-related muscle weakness, new findings indicate that HT use likely has no significant beneficial or detrimental effect on muscle mass in postmenopausal women.
Researchers from McMaster University in Ontario, Canada, arrived at their conclusion after performing a systematic review and meta-analysis of 12 randomized controlled trials (N = 4474) of HT-treated postmenopausal women aged 50 years or older compared with placebo-treated or untreated controls. Participants in 15 of 22 HT intervention arms had been treated with estrogen-progesterone combination HT, while the remaining 7 had received estrogen-only HT. Median follow-up lasted 2 years.
Data for the present analysis were obtained from MEDLINE, Embase, AgeLine, CINAHL, and SportDiscus databases, and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to examine the quality of evidence. All studies included in the present analysis had assessed lean body mass (LBM) or fat-free mass as an outcome. Studies with participants from hospitals, long-term care facilities, or with specific diseases were not eligible for inclusion.
The primary outcome was defined as the overall absolute change in LBM in kilograms. This outcome was measured via dual-energy x-ray absorptiometry, dual-photon absorptiometry, or bioelectrical impedance analysis imaging.
Results showed that participants in 7 HT-treated arms had experienced a loss of LBM, whereas in the remaining 14 arms, HT had demonstrated a protective effect. Ultimately, HT users lost an overall 0.06 kg less LBM compared with control participants. However, this difference did not reach statistical significance.
Stratification based on treatment type and dosage, duration of follow-up, time since menopause, study quality, and type of LBM measurement did not alter these results. For all strata, HT users lost between 0.06 kg more to 0.20 kg less LBM compared with controls. However, the researchers noted that the quality of evidence based on GRADE was low.
“Although muscle retention in aging women is of crucial importance, these findings suggest that interventions other than HT should be explored,” the researchers wrote.
Javed AA, Mayhew AJ, Shea AK, Raina P. Association between hormone therapy and muscle mass in postmenopausal women: a systematic review and meta-analysis. JAMA Netw Open. 2019;2(8):e1910154. doi:10.1001/jamanetworkopen.2019.10154.