Short-term urogenital effects of raloxifene, tamoxifen, and estrogen

Abstract

Objective: The purpose of this study was to assess the urogenital effects of raloxifene, tamoxifen, conjugated equine estrogen, and placebo in healthy postmenopausal women.

Study design: This randomized, double-blind, placebo-controlled study compared the urogenital effects of 0.625 mg of conjugated equine estrogen (n = 15 women), 20 mg of tamoxifen (n = 14 women), 60 mg of raloxifene, (n = 15 women), and placebo (n = 13 women). Evaluations at baseline and evaluations after 20 weeks receiving the drug included a pelvic examination with cytologic evaluation of vagina and urethra, pelvic organ prolapse quantitation, and urethral axis deflection by cotton swab test (only in patients with incontinence [33%]).

Results: Conjugated equine estrogen increased the maturation value of both urethral and vaginal cytologic condition (P =.002, P =.032, respectively). There was a decrease in vaginal maturation value in the raloxifene group (not significant). Two of 8 women in the conjugated equine estrogen group showed evidence of worsening prolapse by pelvic organ prolapse quantitation; the condition of 2 of 8 women improved. In the raloxifene, tamoxifen, and placebo groups 8 of 12 women, 4 of 13 women, and 2 of 11 women had worsening in prolapse scores, respectively, whereas none of the women had improvement. Increased cotton swab deflection was found in 3 of 5 women in the raloxifene group, in 5 of 8 women in the tamoxifen group, in 0 of 4 women in the placebo group, and in 0 of 2 women in the conjugated equine estrogen group. Seventy-five percent of the patients who received raloxifene and 60% of the patients who received tamoxifen had increases in prolapse by any measure (ie, pelvic organ prolapse quantitation or cotton swab or clinical assessment) compared with 18% of the patients in the placebo group and 22% of the patients in the conjugated equine estrogen group (P =.015), although symptoms did not differ among groups.

Conclusion: Neither raloxifene nor tamoxifen improve cytohormonal effects in the vagina or urethra, whereas conjugated equine estrogen does. Raloxifene and tamoxifen appear to show worsening prolapse compared with conjugated equine estrogen and placebo. The clinical relevance of these effects is unknown and requires investigation.