Eating disorder and type 1 diabetes: overview and summing-up

Abstract

The subject of concurrent eating disorder (ED) and insulin-dependent diabetes mellitus (IDDM) has attracted considerable attention for more than a decade. This paper is the first attempt at a quantitative summary of this field. Uncontrolled studies and anecdotal reports suggest an increase of ED in IDDM patients, and also an increase of IDDM in ED patients. Reviews and case reports underscore the difficulty of treating patients with both disorders, the early occurrence of neurovascular complications in these patients and the need for controlled studies. Meta-analysis of five controlled studies do not support an hypothesis of increased risk of ED in female IDDM patients for any type of ED: (anorexia nervosa, AN; bulimia nervosa, BN; unspecified or subclinical ED, ED-NOS). Findings from register studies do not support an hypothesis of increased occurrence of IDDM in female AN-patients. An hypothesis of increased risk of retinopathy is supported by two controlled studies. The interest in concurrent ED and IDDM is thus not justified by any increase in concurrence, but in the early occurrence of clinically significant retinopathy (OR 8·04; 95 per cent CI 4·0–16·1), and other diabetic complications. The existing studies do not seem to have taken full advantage of existing diabetes-specific knowledge, whereas knowledge related to the eating disorders are fully incorporated. Future epidemiological studies should be cause-seeking rather than merely descriptive. These studies should try to relate risk factors, protective factors and specific risk behaviours with health outcome i.e. complications and mortality. © 1998 John Wiley & Sons, Ltd and Eating Disorders Association.