Oral Contraceptives May Limit Bone Loss in Young Anorexic Patients
Apr 16, 2019
Origin: ASRM Press Release
French researchers have identified a promising protective effect of oral contraceptives on the bone health of young women with anorexia nervosa. Along with the gynecological disorders resulting from anorexia, patients experience bone loss with intense demineralization early in the course of the disease. This study shows for the first time that anorexia patients using oral contraceptives (OCs) have a higher areal bone mineral density than those who do not use OCs and suggests that, while regularly taking an oral contraceptive will not confer complete protection, it may help to limit bone loss in young women suffering from anorexia nervosa.
The case-control study, conducted at Montpellier University Hospital in France, enrolled 426 young and adolescent women, ranging in age from 14.5 to almost 35. Of the participants, 305 were patients being seen for anorexia nervosa (AN) in the hospital’s Endocrinology Department and 121 were healthy controls, with normal menstrual cycles and no history of eating disorders, recruited from the community.
Participants’ areal bone mineral density (aBMD) was measured at specific sites (lumbar spine, femoral neck, hip, and radius) and in addition, for the whole body. Metabolic markers of bone turnover and leptin levels were measured as well.
Comparing patients with age-matched controls, the researchers found all of the patients suffering from anorexia had lower aBMD values than the controls for all specific sites, even though their whole body aBMD measurements were comparable. However, the AN patients who took oral contraceptives (OCs) had systemically higher aBMD values- at specific sites and whole body- than AN patients who did not take OCs. The researchers did not find a similar difference in aBMD between users and non-users of OCs among the healthy controls.
Several factors influenced the degree of the beneficial effects OCs exerted. The longer the time a patient had been taking OCs, the more improved her aBMD was. Likewise, a shorter amount of time between the onset of AN and the start of OC use was associated with better aBMD. Interestingly, patients with the lowest BMI had the best response to OCs.
Compared to controls, markers for bone formation were lower in AN patients- in both OC users and non-users. Bone resorption markers were normal in OC-using AN patients, but elevated in patients who did not use them.
Christos Coutifaris, MD, PhD, Immediate Past-President of ASRM noted, “In girls and young women with anorexia, bone loss can be observed as soon as six months after the onset of the disease. Losing or failing to develop bone at a time of life when they should be building maximum bone density, they may be at increased risk for fractures and osteoporosis throughout their lives. While the researchers wisely observe that oral contraceptives should not be seen as the only intervention to help protect anorexia nervosa patients against bone loss, OCs may provide a foothold, a way to stabilize the loss while the anorexia itself is treated.”
In a comment accompanying the paper, Dr. Sarah Berga discusses the significance and clinical applications of the research. In pursuit of middle ground: understanding the bone benefits of hormonal contraception in women with anorexia nervosa. Fertility and Sterility, in press.