Muscle strength and tibolone: a randomised, double-blind, placebo-controlled trial.
OBJECTIVE
To investigate the effects of tibolone, a tissue-specific compound with a mixed (estrogenic, progestogenic and androgenic) hormonal profile, on skeletal muscle strength in a group of healthy postmenopausal women.


METHODS
Randomised, parallel group, double-blind, placebo-controlled, single-centre trial conducted between August 1997 and July 1999.


METHODS
Eighty-five healthy women, between one and 15 years postmenopausal, (mean [SD] age, 54.2 [4.7] years) recruited from local paper advertisements. Participants were randomly assigned to 2.5 mg tibolone or to identically appearing placebo pills daily for 12 months, taken orally in the morning.


METHODS
Both maximal handgrip strength, representing upper body strength, and maximal quadriceps strength, representing lower body strength, were measured isometrically.


METHODS
Treatment effect estimates (between group differences) in handgrip strength and isometric knee extension at last visit.


RESULTS
Tibolone significantly (P = 0.04) increased handgrip strength compared with placebo (difference 0.99 kg, [95% CI 0.1-1.9]). No significant treatment effect (P = 0.61) was observed in isometric knee extension strength. Isometric strength adjusted for body mass index resulted in a trend favouring tibolone (P = 0.06). Individual trend analysis showed a significant difference in rate of change throughout the year (6.8% [95% CI 2.1-10.7]) favouring tibolone.


CONCLUSIONS
Administration of tibolone increased handgrip strength in postmenopausal women compared with placebo. A trend indicating a positive effect in isometric knee extension strength adjusted for body mass index was observed. Tibolone seems to mitigate the menopause-related decline in muscle strength.
Meeuwsen
Ingrid B A E
IB
Department of Geriatric Medicine, University Medical Centre, Utrecht, The Netherlands.
Samson
Monique M
MM
Duursma
Sijmen A
SA
Verhaar
Harald J J
HJ
D000284:Administration, Oral; D000726:Androgen Antagonists / Q000627:therapeutic use*; D015992:Body Mass Index; D004311:Double-Blind Method; D020847:Estrogen Receptor Modulators / Q000627:therapeutic use*; D015444:Exercise / Q000502:physiology; D005260:Female; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000502:physiology; D009652:Norpregnenes / Q000627:therapeutic use*; D017698:Postmenopause / Q000187:drug effects / Q000502:physiology
D000726:Androgen Antagonists; D020847:Estrogen Receptor Modulators; D009652:Norpregnenes; C027385:tibolone