Secular trends in the incidence of eating disorders in China from 1990 to 2017: a joinpoint and age-period-cohort analysis

Background Eating disorders (ED) have increasingly become a global topic of concern for public health. A better understanding of ED incidence is a basic requirement for improving its management. However, the temporal trend of ED incidence in China is still unknown. Methods The incidence rates of ED from 1990 to 2017 were collected from the Global Burden of Disease Study 2017 database according to the following: subtype, i.e. anorexia nervosa (AN) and bulimia nervosa (BN); sex; and age group. The average annual percent changes and relative risks were calculated using joinpoint regression and the age-period-cohort model, respectively. Results From 1990 to 2017, age-standardized incidence rates of ED continued to increase in males and females, and this variation trend was observed in AN and BN. Joinpoint regression analysis showed that the incidence rates increased in all age groups. Adolescents had the highest risk of developing ED, followed by young adults. Age effects were the most influential risk factor for ED incidence. Period effects showed that the risk of developing ED continuously increased with increasing time periods in BN, but not in ED and AN. Concerning the cohort effects, people born after the 1990s presented a higher risk of ED, though they presented a lower risk of BN as compared to the whole cohort. Conclusions ED incidence rates continue to increase in China, particularly among adolescents and young adults. Further etiological studies are needed to explain these increases and to facilitate the early identification of high-risk individuals.