More than 50% of all fractures occur in people without osteoporosis. Hormone therapy increases bone density, improves postural balance, and reduces fracture risk in postmenopausal women. It is unclear whether tibolone, a synthetic steroid hormone drug, can improve muscle strength. Thus, the aim of this study was to study the effects of low-dose tibolone therapy on muscle strength in older women.
Eighty healthy women (69 completed the study) 60 years or older were recruited through advertising in the local media. They were randomly allocated to receive either tibolone 1.25 mg/day or placebo for 6 months. The stand-up test was used to assess leg muscle strength and balance. Handgrip and leg muscle strength were measured using JAMAR and modified Cybex dynamometers.
Baseline characteristics, including serum estradiol values and muscle strength, were similar in the two groups. Compliance with the therapy regimen was very high, averaging more than 97% in both groups. After 6 months, mean values for handgrip strength, knee extensor strength, and average time to perform 10 stands were improved numerically in both groups compared with values during baseline. However, there were no significant differences in these parameters within or between groups, and differences remained nonsignificant after adjustment for age, serum estradiol, and baseline value.
Short-term treatment with low-dose tibolone (1.25 mg/d) seems not to affect muscle strength in older women.
Six months of tibolone treatment did not affect handgrip or leg muscle strength when compared with placebo treatment in postmenopausal women.
From the 1Department of Surgical Sciences, Orthopedic Unit, Uppsala University; 2Physiotherapy Ward, Uppsala University Hospital, Uppsala, Sweden; 3NV Organon, Oss, the Netherlands; and 4Department of Women's and Children's Health, Section for Obstetrics and Gynecology, Uppsala University, Uppsala, Sweden.
Received March 31, 2010; revised and accepted May 20, 2010.
Funding/support: Financial support was received from the Swedish Society of Medicine (no. 99-02-0248), the Selanders Foundation, and the Family Planning Foundation, Uppsala, Sweden, and NV Organon, part of Schering-Plough, Oss, the Netherlands, who also kindly provided the active and placebo tablets.
Financial disclosure/conflicts of interest: None reported.
Address correspondence to: Eva L. Ribom, PhD, Physiotherapy Ward, Entrance 85, University Hospital in Uppsala, s-751 85, Uppsala, Sweden. E-mail: firstname.lastname@example.org