Childhood BMI Tied to Later Eating Disorder Risk

Low BMI associated with higher risks for anorexia, higher BMI associated with increased risks for bulimia

WEDNESDAY, May 26, 2021 (HealthDay News) — Childhood body mass index (BMI) is associated with a later risk for eating disorders, according to a study presented at the European Congress on Obesity, held virtually from May 10 to 13.

Britt Wang Jensen, Ph.D., from Bispebjerg and Frederiksberg Hospital in Copenhagen, Denmark, and colleagues examined whether BMI during childhood was associated with a subsequent diagnosis of anorexia nervosa (AN) and bulimia nervosa (BN) through age 50 years. The analysis included 66,576 girls (born from 1960 to 1996) who had weights and heights measured at school health examinations from the ages of 7 to 13 years with data linked to the Danish National Patient Register and the Danish Psychiatric Central Research Register.

The researchers identified 514 cases of AN and 315 cases of BN, with a median age at diagnosis of 19.9 years and 22.5 years, respectively. There was a significant, inverse relationship between BMI z-scores and the risk for AN (a one z-score increase in BMI at age 7 years: hazard ratio [HR], 0.86; at age 13 years: HR, 0.72). For BN, there was a significant, positive association between BMI z-score and the risk for BN (one z-score increase in BMI at age 7 years: HR, 1.50; at age 13 years: HR, 1.33). Compared with girls with normal weight at age 7 years, being overweight was associated with a higher risk for BN; this was also true for girls at age 13 years; however, the risk was lower.

“The difference in childhood BMI of girls who later developed eating disorders started to emerge at an early age,” Jensen said in a statement. “These results highlight the importance of regularly monitoring weight and height during childhood to identify these patterns as early as possible.”