Raloxifene and Tibolone in Elderly Women: A Randomized, Double-Blind, Double-Dummy, Placebo-Controlled Trial

Abstract

The authors' first aim was to study the effects of raloxifene and tibolone on body mass density, handgrip strength, and other secondary frailty components. The secondary aim was to compare the effects of raloxifene and tibolone and their safety in older women. A randomized, double-blind, double- dummy, placebo-controlled trial conducted in an academic hospital in the Netherlands among 318 community living women aged >70 were randomized; 290 received the allocated intervention: 97 placebo, 101 raloxifene, and 92 tibolone. Randomization was made to raloxifene 60 mg, tibolone 1.25 mg, or placebo. Assessments were performed at baseline and after 3, 6, 12, and 24 months. The study was conducted from July 2003 to January 2008. The tibolone group stopped earlier in February 2006, because of results of the Long-Term Intervention on Fractures with Tibolone study, suggesting an increased risk of cerebrovascular accident. Primary endpoints were body mass density and handgrip strength. Secondary endpoints were muscle power and strength, mobility measures, body composition, verbal memory, mental processing speed, anxiety, mood, and quality of life. Tibolone and raloxifene had similar body mass density-effect sizes (d= .24-.47), and had no effect on handgrip muscle strength. For the 15 words test the effect on direct recall of concrete and abstract words (d= .40 and d=.27, respectively) and on delayed recall of concrete words (d= .77) were significantly higher in the raloxifene group compared to placebo and to tibolone. In the raloxifene group the health status (EuroQol VAS (0-100) was improved 2.4 points [95% CI 0.5-4.2; P= .012] over 24 months. In women >70 years old, raloxifene and tibolone significantly and similarly increased body mass density but not muscle strength. Raloxifene had also positive effects on verbal memory and health status. New research with selective estrogen receptor modulators like raloxifene might be promising on frailty endpoints in elderly women. Nederlands Trial Register: 1232.