Once Again, the Diagnostic Value of Amenorrhea in AN Is Questioned

Amenorrhea has long been one of the cornerstones of a clinical diagnosis of anorexia nervosa (AN). More recently, more and more groups have begun to question the validity of amenorrhea as a criterion for the diagnosis of AN.

Researchers at Virginia Commonwealth University, Richmond, and Christchurch School of Medicine, Christchurch, New Zealand, designed a study to investigate variables associated with amenorrhea in persons with AN, and attempted to clarify the significance of amenorrhea as a diagnostic criterion for the disease. The study included 39 women 17 to 40 years of age with diagnoses of AN according to either: (1) strict criteria, such a body mass index (BMI) less than 17.5 kg/m2 or (2) lenient weight criteria, including a BMI of 17.5-19 kg.m2. The subjects did not have to have amenorrhea to be included in the study.

Kelly A. Gendall, PhD and colleagues assessed the patients with the Structured Clinical Interview for DSM-IV, the Hamilton Rating Scale for Depression, the Eating Disorders Examination and additional questions about eating and weight history. The participants also completed the Temperament and Character Inventory and kept a 7-day diet record. Weight, height, body fat, blood pressure and heart rate were measured and blood samples were taken.

Three predictors of amenorrhea

Two-thirds of the women with strict criteria AN had amenorrhea and half with lenient criteria had amenorrhea. After controlling for BMI, younger age of AN onset, low systolic blood pressure, low pulse rate, using exercise to control weight, being a nonsmoker, not being in a current sexual relationship, low novelty-seeking behavior, and high persistence were associated with amenorrhea.

Exercise, low systolic blood pressure, and low novelty-seeking scores emerged as predictors of amenorrhea. These three factors successfully predicted 88% of women with, and 85.7% of those without, amenorrhea. Amenorrhea was also associated with lower body fat percentage, low levels of thyroid hormones, and lower leptin concentrations in the subgroup with strict criteria AN. Energy intake and macronutrient intake were similar in all groups.

Dr. Gendall and colleagues, who reported their study at the AED meeting in Denver, concluded that constrained personality features, expending energy in excess of intake, and certain indirect measures of reduced resting metabolic rate appear to be associated with amenorrhea in AN. According to the authors, the relative absence of a distinguishing eating disorder or psychopathological profile specifically tied to amenorrhea casts doubt upon the value of amenorrhea as a diagnostic criterion for AN.