Risk factors for anorexia nervosa and bulimia nervosa in Japan and compared to a U.S. sample

This study provides the first systematic investigation of environmental exposure to putative psychosocial risk factors for eating disorders in individuals with AN and BN in Japan. It also provides a comparison of risk factors for the development of AN and BN in Japan versus the United States.

Participants in Japan were 96 women with a current DSM-IV AN or BN primary diagnosis (AN, n = 60; BN, n = 36) and 57 women with no current psychiatric diagnosis (NC group). Participants in the United States were 137 women with a current DSM-IV AN or BN primary diagnosis (AN-U.S., n = 71; BN-U.S., n = 66). A standardized semi-structured interview retrospectively assessed exposure to risk factors prior to first symptom onset, which were analyzed using General Linear Model analyses.

Perfectionism and negative affectivity, family relationship issues, and, to a lesser degree, parental psychopathology predicted the emergence of AN and BN in Japan. Physical and sexual abuse and family eating and weight concerns were not significant risk factors in Japan. Compared to their respective diagnostic U.S. groups, the Japanese AN group reported higher levels of individual mental health factors and lower levels of family dieting and family overweight, and the Japanese BN group reported higher levels on individual mental health factors, lower exposure to problems with their parents, and lower exposure to family weight and eating concerns.

These country-specific data from Japan contribute to an increasingly nuanced and global understanding of risk factors for eating disorders.