Objective: Anorexia nervosa (AN) is often associated with severe mineral bone loss and increased risk of fractures. The objective of this study was to assess the bone mineral density (BMD) in patients with AN and its relationship with different anthropometrics, clinical and hormonal parameters.
Patients and methods: We evaluated 47 women with AN according to criteria of DSM-IV. The anthropometrics variables measured were: weight (kg) height (m), BMI (kg/m2) and corporal composition. The body fat were measured using a bioelectrical impedance analysis system (TANITA). Hormonal profile: estradiol and IGF-1.
The BMD was performed using dual-energy X-ray absorptometry (DXA) in lumbar spine (LS) and femoral neck (FN). WHO criteria were used for defining osteoporosis: T-score ≤−2.5 S.D. Statistics analysis: the data were evaluated using SPSS 12.0. P value set at 0.05 as a minimal level of significance.
Results: Clinical characteristics: mean age (±S.D.): 22.2±3.5 years, BMI 17.7±2.4 kg/m2, disease duration 33.3±9.2 months and amenorrhea duration 17.8±months.
Sixteen woman (34%) were diagnosed of osteoporosis in LS and 3 (6.5%) in FN.
|BMD Lumbar||T-Score Lumbar||Amenorrhea duration|
|Amenorrea duration (months)||−0.44||0.03||−0.45||0.02|||||
|Body fat (%)||0.57||0.03||0.60||0.01||−0.46||0.01|
Conclusion: The women with AN have a decreased BMD in LS and FN, but the lumbar spine is mostly affected by a major risk of fractures. The fat mass loss and the estrogen deficiency are, both, a very important risk factors to the BMD loss, fundamentally to level of LS. The amenorrhea depends fundamentally on nutritional factors.