By: Walter Kaye, MD, Professor of Psychiatry, Director, UCSD Eating Disorder Research and Treatment Program, University of California, San Diego
While it is well known that anorexia nervosa is a deadly disorder, the death rate varies considerably between studies. This variation may be due to length of follow-up, or ability to find people years later, or other reasons. In addition, it has not been certain whether other subtypes of eating disorders also have high mortality. Several recent papers have shed new light on these questions by using large samples followed up over many years. Most importantly, they get around the problem of tracking people over time by using national registries which report when people die. A paper by Papadopoulos studied more than 6000 individuals with AN over 30 years using Swedish registries. Overall people with anorexia nervosa had a six fold increase in mortality compared to the general population. Reasons for death include starvation, substance abuse, and suicide. Importantly the authors also found an increase rate of death from ‘natural’ causes, such as cancer.
It has not been certain whether mortality rates are high for other eating disorders, such as bulimia nervosa and eating disorder not otherwise specified, the latter of which is the most common eating disorder diagnosis. Crow and colleagues studied 1,885 individuals with anorexia nervosa (N=177), bulimia nervosa (N=906), or eating disorder not otherwise specified (N=802) over 8 to 25 years. The investigators used computerized record linkage to the National Death Index, which provides vital status information for the entire United States, including cause of death extracted from death certificates. Crow and colleagues found that crude mortality rates were 4.0% for anorexia nervosa, 3.9% for bulimia nervosa, and 5.2% for eating disorder not otherwise specified. They also found a high suicide rate in bulimia nervosa. The elevated mortality risks for bulimia nervosa and eating disorder not otherwise specified were similar to those for anorexia nervosa.
In summary, these findings underscore the severity and public health significance of all types of eating disorders.