Norethindrone acetate or dienogest for the treatment of symptomatic endometriosis: A before and after study

Objective To assess the proportion of patients satisfied with their treatment before and after a systematic change from norethindrone acetate to dienogest as the first-line progestin for symptomatic endometriosis. Design Before and after study. Setting Academic department. Patient(s) The last 90 new consecutive endometriosis patients in whom norethindrone acetate was used, and the first 90 new consecutive endometriosis patients in whom dienogest was used. Intervention(s) Norethindrone acetate at the oral dose of 2.5 mg once a day until June 6, 2013, then dienogest at the oral dose of 2 mg once a day thereafter. Main Outcome Measure(s) Degree of satisfaction with treatment after 6 months of progestin therapy and assessment of any variations in pain symptoms, psychological status, sexual function, or health-related quality of life associated with the introduction of dienogest. Result(s) The proportion of satisfied plus very satisfied women after 6 months of treatment was 71% in the "before" period (norethindrone acetate) and 72% in the "after" period (dienogest). The implementation of dienogest was not associated with statistically significant ameliorations in overall pain relief, psychological status, sexual functioning, or health-related quality of life. Treatment was well tolerated by 58% of norethindrone acetate users compared with 80% of dienogest users. After dienogest implementation, the absolute risk reduction in the occurrence of any side effect was 13.9% (95% confidence interval, 0.8%-28.6%). Conclusion(s) Considering the large difference in the cost of the two drugs, dienogest should be suggested selectively in women who do not tolerate norethindrone acetate.