Raloxifene effects on vasomotor and other climacteric symptoms in postmenopausal women

Introduction and Objectives: Raloxifene, a novel selective estrogen receptor modulator (SERM), is under investigation for the prevention of osteoporosis in postmenopausal women. Like traditional estrogen replacement therapy, raloxifene has beneficial effects on bone and on serum lipids whereas, in contrast to estrogen's adverse effects in the breast and uterus, raloxifene is an estrogen antagonist in the breast and is nonstimulatory in the uterus. This study examines the effects of raloxifene 60 mg/day compared with placebo on: 1) the incidence of vasomotor symptoms: hot flashes (flushing) and sweating (including night sweats), 2) the severity and time course of hot flashes, and 3) the relation of hot flashes to baseline subject characteristics and study discontinuations. Additionally, the study explores the effects of raloxifene 60 mg/day compared with placebo on other climacteric symptoms that affect the quality of life of postmenopausal women, such as depression, insomnia, mood lability and genitourinary complaints.Methods: Integrated data from five randomized, placebo-controlled studies involving 1,165 healthy, postmenopausal women, with up to 30 months of study drug exposure, were analyzed. The incidence and severity of hot flashes and other climacteric symptoms were compared in patients treated with placebo or raloxifene (60 mg/day) via open-ended, non-directed subject self-assessment questionnaires. Data were analyzed for subgroup-by-therapy interactions using many baseline subject characteristics such as age, body mass index, smoking, alcohol, and years post-menopause, as well as preexisting conditions such as hot flashes, sweating, insomnia, depression, and history of hysterectomy. The overall incidence of other climacteric symptoms were reported as adverse events.Results: The increase in overall incidence of hot flashes in raloxifene-treated (24.6%) and placebo-treated (18.3%) subjects was modest, but statistically significant. However, this difference was significant only during the first 6 months of therapy, raloxifene (20.1%) compared with placebo (14.4%). After 6 months of treatment, there was no statistically significant difference in the incidence of hot flashes between the two treatment groups. The majority of hot flashes in raloxifene-treated subjects were subject-assessed as "mild-to-moderate" in severity (89%). The incidence of hot flashes reported as "severe" did not differ significantly in raloxifene- or placebo-treated subjects. Subgroup analyses revealed the overall incidence of hot flashes to be highest for both raloxifene and placebo-treated subjects, in younger (age < 55 years) women (P =.004), in women who had previously experienced hot flashes (P =.031), and in women having had hysterectomies (P <.001). Within each of these subgroups, there was no statistical difference in the incidence of hot flashes between the raloxifene and placebo groups. Between the two treatment groups, there was no difference in the overall incidence of subject discontinuations from study due to hot flashes. The occurrence of the other common vasomotor symptom, sweating (which includes night sweats), was not statistically different for the raloxifene- or placebo-treated subjects.Genitourinary complaints are often symptoms related to vaginal dryness, such as dyspareunia and decreased libido, as well as other symptoms of vaginitis and leukorrhea. No statistically significant differences occurred for raloxifene- or placebo-treated subjects in reports of these genitourinary symptoms. Similarly, for the other common climacteric symptoms; depression, insomnia, and mood lability, no significant differences in incidence between the raloxifene and placebo treatment groups were observed.Conclusions: Raloxifene (60 mg/day) treatment modestly increased the incidence of hot flashes compared with placebo, however, this difference was only statistically significant during the first 6 months of treatment. There were no differences in the severity of hot flashes between treatment groups, and this symptom did not adversely affect subjects' study participation. In both the raloxifene and placebo treatment groups, young postmenopausal women (age < 55), those with baseline hot flashes, and those with histories of hysterectomy were most likely to experience hot flashes. Raloxifene therapy did not affect the occurrence of other climacteric symptoms commonly affecting the quality of life of women after menopause.