THE EFFECT OF ADD-BACK TREATMENT WITH TIBOLONE (LIVIAL) ON PATIENTS TREATED WITH THE GONADOTROPIN-RELEASING-HORMONE AGONIST TRIPTORELIN (DECAPEPTYL)

Objective: To assess whether tibolone can prevent the bone loss and sy mptomatic side effects normally associated with GnRH agonist (GnRH-a) use and whether tibolone modifies the effect of GnRH-a on endometriosi s. Design: Prospective, double-blind, placebo-controlled, group compar ative study. Setting: Gynecological research unit in a London teaching hospital. Patients: Twenty-nine patients with endometriosis and two w ith fibroids. Interventions: Six months of treatment with 3.75 mg/mo I M triptorelin combined with daily tablets of either placebo or 2.5 mg tibolone. Main Outcome Measures: Daily symptom diary for hot flushes a nd bleeding episodes, laparoscopic scoring of endometriosis, endocrine and biochemical changes, and bone mineral density scans. Results: Lum bar spine bone mineral density decreased significantly from baseline i n the placebo group (-5.1%) but not in the tibolone group (-1.1%). The frequency of hot flushes and sweating episodes was reduced significan tly by tibolone. There was no difference between the two treatment gro ups with regard to the endometriosis scores. Conclusions: The addition of tibolone to GnRH-a treatment reduces the bone loss and vasomotor s ymptoms that normally occur with GnRH-a, thus making long-term treatme nt with GnRH-a safer and more acceptable. It does not negate the thera peutic effect of GnRH-a on endometriosis.