Gallbladder disease risk similar regardless of oral contraceptive
Media reports in recent years about an excess risk for gallbladder disease with the oral contraceptive drospirenone (Yasmin, Bayer) are unfounded, data indicate.
“Any excess risk associated with the use of drospirenone merits quantification within the context of a comparative safety study,” Mahyar Etminan, Pharm D, MSc, an assistant professor of medicine at the University of British Columbia in Vancouver, Canada, and colleagues wrote in the Canadian Medical Association Journal.
To explore this risk, they determined adjusted rate ratios for gallbladder disease among a retrospective cohort that included 2,721,014 women who had taken oral contraceptives continuously for six months between 1997 and 2009.
Women included in the cohort were part of the IMS LifeLink Health Plan Claims Database and had used an oral contraceptive containing ethinyl estradiol combined with a progestin — either norethindrone, ethynodiol diacetate, norgestrel, levonorgestrel, norgetimate, desogestrel or drospirenone.
The primary outcome was cholecystectomy, defined by CPT codes for both surgical and laparoscopic procedures; secondary outcomes were ICD-9 codes for hospital admission secondary to gallbladder disease. A total of 27,087 women underwent a cholecystectomy during the follow-up period.
Compared with levonorgestrel, an older second-generation progestin, the researchers found a small, statistically significant increase in the risk for gallbladder disease with three newer progestins: drospiredone (adjusted risk rate ratio=1.20, 95% CI: 1.16-1.26), desogestrel (adjusted RR: 1.05, 95% CI: 1.01-1.09) and norethindrone (adjusted RR=1.10, 95%CI: 1.06-1.14).
Despite these findings, these increases are probably not clinically significant, the researchers wrote, citing “small effect sizes” and “residual biases.” Media reports might have fueled reporting bias, they added.
“The surge in the number of reported cases of gallbladder disease facilitated through the media may have contributed in making drospiredone appear to be associated with a higher risk of gallbladder disease compared with older contraceptives,” the researchers wrote.
Increased risk was not associated with any of the other oral contraceptive formulations.