Predictors of late menarche and adult height in children with anorexia nervosa

Abstract

Objectives: The onset of anorexia nervosa (AN) during childhood can affect the timing of puberty and adult height. The aim of the study was to evaluate the determinants of late menarche and adult height in children with AN.

Patients and methods: We carried out a retrospective, longitudinal, university hospital-based study. All prepubertal or early pubertal girls diagnosed with AN between 1998 and 2002 were selected for the study. Participants (n = 33) were studied at a median age of 21 (19.8-24.3) years. AN was diagnosed at 11.8 (10.7-12.3) years.

Results: Patients with AN reached menarche at significantly greater ages than their mothers [15.4 (13.5-16.8) vs. 13.2 (12.0-14.5) years, P < 0.01]. Chronological age at onset of AN and lowest body mass index (BMI) were important independent predictive factors for delayed menarche (P < 0.01). Adult height was 165.0 (163.0-172.0) cm, 2.5 (-1.5 to 5.0) cm above target height. Twelve patients (36%) did not reach their target height and had a median height deficit of -3.9 cm with respect to their target height. The duration of hospitalization, a marker of disease severity and chronicity, was an independent predictor of the difference between adult height and target height for a given individual (beta coefficient = -0.07; P = 0.01). The other factors studied (i.e. age at onset of AN, pubertal stage at diagnosis of AN, lowest BMI reached, associated comorbidity if any, type of AN, age at menarche) had no significant effect on adult height.

Conclusion: The intensity of the disease affects the timing of menarche but not adult height in most patients. Hospitalization, despite often being an effective means of managing AN, does not reduce the impact of AN on growth.