Menstrual Patterns Among Patients With Anorexia Nervosa and Avoidant/Restrictive Food Intake Disorder: Does "Junk Food" Play a Role?

PURPOSE: Few studies have examined menstrual differences between patients with anorexia nervosa (AN) versus avoidant/restrictive food intake disorder (ARFID). After observing that many patients with ARFID maintain regular menses despite weight loss, we sought to characterize these menstrual differences in the context of specific eating behaviors.

METHODS

Patients with AN or ARFID in a disordered eating database at the University of Oklahoma Health Sciences Center were included. Bivariate analyses explored group differences in demographics, age, percentage of median body mass index for age (%mBMI), time since last menstrual period (LMP), and reported eating behaviors, including whether self-reported diet history included "junk food" consumption in the past 24 hours. Regression analysis examined whether diagnosis and variables that were associated with diagnosis significantly predicted time since LMP.

RESULTS

The analyses included 89 participants diagnosed with AN or ARFID (AN: n = 70; ARFID: n = 19). The AN group had higher %mBMI for age than the ARFID group (83.4% vs 76.4%, respectively, P = .004) and was less likely to have reported consuming junk food the day prior (36.8% vs 76.5%, respectively, P = .003). Time since LMP was longer for those with AN versus ARFID (174 vs 13 days, respectively, P < .0001). A 2-predictor model with diagnosis and junk food explained a significant proportion of variance in time since LMP (P = .012).

CONCLUSION

This paper may be the first to describe menstrual differences among individuals with AN and ARFID in the context of eating behaviors. In addition to diagnosis, having no self-reported junk food consumption in the past 24 hours was significantly associated with longer time since LMP. Studies that include specific measures of food intake and hormonal responses to food quality are warranted to further explore the etiology of menstrual differences among patients with AN and ARFID.