HORMONE REPLACEMENT THERAPY .1. PHARMACOECONOMIC APPRAISAL OF ITS THERAPEUTIC USE IN MENOPAUSAL SYMPTOMS AND UROGENITAL ESTROGEN DEFICIENCY

Menopause and the accompanying reduction in estrogen production may ca use a number of symptoms in women which include hot flushes, sweating, mood and sleep disturbances, fatigue and urogenital dysfunction. The effectiveness of estrogen-based hormone replacement therapy (HRT) in a meliorating these symptoms, and in preventing long term sequelae such as osteoporosis, is well established. Comparative trials indicate that oral conjugated estrogens 0.625mg, oral ethinyl estradiol 0.02mg and transdermal estradiol 0.05mg have equivalent efficacy in relief of mil d to moderate menopausal symptoms and prevention of bone mineral loss. Concomitant progestogen therapy is usually prescribed for women with intact uteri to protect against endometrial hyperplasia and carcinoma. The addition of progestogen maintains and may even enhance the bone-c onserving effects of estrogen, and continuous regimens appear to reduc e the incidence of irregular menses. Adverse reactions are predominant ly local skin irritation with transdermal preparations (14% of patient s) and systemic effects common to most forms of HRT including breast t enderness, flushing, headache and irregular bleeding, occurring in les s-than-or-equal-to 2% of patients. Data concerning the effect of HRT o n quality of life are limited, but most analyses have assigned utility values of 0.99 for mild and 0.95 for severe menopausal symptoms. Howe ver, recent clinical data suggest that these utility values may undere stimate the impact of menopausal symptoms on quality of life. The cost benefit and cost effectiveness of HRT in the treatment of menopausal symptoms have not been fully researched, although preliminary results suggest that conjugated estrogens and transdermal estradiol compare we ll with alternative therapies such as veralipride and Chinese medicine s. A Swedish study using a prevalence-based approach estimated that es triol treatment in all women with urinary incontinence aged greater-th an-or-equal-to 65 years resulted in monetary savings compared with tre ating 20% of women. Cost-utility data indicated that the change in qua lity-adjusted life years (QALYs) with HRT was always positive, but the degree of change was determined by the baseline assumptions. Estimate d changes in QALYs with HRT ranged from 0.006 for 5 years of treatment with unopposed estrogen in women with intact uteri, to 0.5 for 10 yea rs of the same treatment in women with severe menopausal symptoms foll owing histerectomy. Compliance with HRT is suboptimal as 5 to 50% of w omen withdraw from therapy, thereby increasing costs per year of life saved. Thus, HRT is both medically and economically justified in women with severe menopausal symptoms, whereas compliance is an important f actor in determining economic benefit in women with less severe sympto ms. During long term therapy the associated beneficial effects on oste oporosis and cardiovascular parameters, and patient monitoring require ments, will assume greater significance.