Does the presence of coexisting diseases modulate the effectiveness of a low-dose estrogen/progestin, ethinylestradiol/drospirenone combination tablet in dysmenorrhea? Reanalysis of two randomized studies in Japanese women

The purpose of this study was to investigate the effectiveness of a combination of ethinylestradiol (EE) and 0.02 mg/drospirenone (DRSP) 3 mg in Japanese women with dysmenorrhea and in particular to determine whether or not the presence of specific coexisting organic diseases (eg, endometriosis, uterine fibroids, uterine adenomyosis) has an impact on treatment. Four hundred and ten patients with dysmenorrhea aged 20 years or older (315 without coexisting organic disease, 28 with endometriosis, 37 with uterine fibroids, and 46 with uterine adenomyosis [some patients had multiple coexisting organic diseases]) were enrolled and treated with EE/DRSP in either a 16-week comparator study or a 52-week long-term safety study. Evaluations included changes in total dysmenorrhea score, visual analog scale for dysmenorrhea, severity of symptoms, hormone levels, endometrial thickness, and safety outcomes. In both studies, the total dysmenorrhea score was significantly (P