Follow-up Reveals the True Aftermath of Anorexia Nervosa

Regardless of their actual weight, patients with anorexia nervosa are usually unhappy about their weight and shape. They are reluctant to accept nourishment and thus avoid gaining weight. Two recent studies have shown that women with a history of anorexia nervosa should be followed longitudinally to detect relapse and compromised bone density.

A return to restriction

Dr. E. Nova and colleagues at Instituto de Nutricion y Bromatologica, Madrid, Spain, reported that after a year of treatment, a follow-up study showed that most AN patients had returned to their old patterns of restrictive eating. This pattern was particularly marked among patients who had regained the most weight.

Among the 14 adolescent patients who had been recruited for the study when admitted for inpatient treatment, then studied at 1 month after admission (inpatient), 6 months (outpatient), and 12 months, increased energy intake was better accepted by increasing the relative contribution of macronutrients other than fat. All anthropometric measurements (height, weight, BMI, subscapular arm fat, etc.) increased significantly between the time the women were admitted and the first month of treatment, and continued 12 months later. Negative correlations were found between energy/fat/carbohydrate intake and the contribution of protein to total dietary energy.

Bone loss 11 years after diagnosis

Results of a second study underscore the fact that resumption of menses and an outward appearance of normal body weight do not guarantee normal bone density in women with a history of anorexia nervosa. When 36 former anorexia nervosa patients were re-evaluated an average of 11 years after the initial diagnosis, 85% had abnormal bone density (J Women’s Health 7:567, 1998). Of those with below-normal bone density, 50% were osteopenic and 35% had osteoporosis. The youngest woman with osteoporosis was 20 years old.

The most common site of bone loss among women 20-45 years of age was reported at the proximal femur; the average T score (World Health Organization T score criteria for osteopenia) was –1.22, and the average femoral neck T score was –1.33. Spinal bone density was also reduced: the average total lumbar Z score (bone mineral density score) was 91% of the mean for age; the total Z score was –0.84.

The authors found a significant correlation between lumbar bone density and total years of estrogen exposure. They also reported a consistent inverse relationship between both femoral and lumbar bone density and mineral content with total years of amenorrhea. The absence of menses may serve as an independent contributor to the compromised bone density seen in both the appendicular and axial skeleton.