Vertebral fracture assessment in adolescents and young women with anorexia nervosa: a case series

Abstract

Rates of vertebral fracture (VF) in young women with anorexia nervosa (AN) are not well understood. We sought to determine the rates of asymptomatic VF in patients suffering from AN, hypothesizing that VF rates would be higher in subjects with low bone mineral density (BMD) Z-scores. We recruited young women with AN (n = 80) for participation in a longitudinal trial. Dual-energy X-ray absorptiometry images of the lateral thoracic and lumbar spines were obtained for VF assessment at 0, 6, 12, and 18 mo. Thirteen subjects (16%) had a low spinal BMD at baseline (BMD Z-score ≤-2 standard deviation). Using the Genant semiquantitative technique, 2 of 80 subjects at baseline (2.5%) had evidence of a single Genant grade 1 deformity. One subject had a Genant grade 2 deformity. Over the 18-mo trial, 10 incident VFs occurred in 9 subjects (12.5%). Using quantitative techniques, only 2 subjects had a more than 15% loss in vertebral height. Neither anthropometric data nor markers of disease severity were associated with fracture. In conclusion, ill young women with AN were at low risk for asymptomatic VF in our cohort. VFs were not predicted by duration of illness, severity of malnutrition, or traditional measures of areal BMD at the lumbar spine.

Keywords: Adolescents; anorexia nervosa; vertebral fracture; vertebral fracture assessment.