The term ‘brittle diabetes’ is commonly used to describe a subset of patients with diabetes mellitus (DM) who exhibit a degree of glycaemic instability that disrupts their daily life, is associated with frequent hospitalisation and carries psychopathological overlap. The continued use of this term and its recognition as a distinct entity is controversial.
We aimed to determine the frequency of use of the term ‘brittle diabetes’ in the published literature, trends in definition over time, and review studies examining a pathophysiologic basis. Despite its common everyday use, we hypothesise that the term lacks scientific basis, is poorly defined and its use should be discouraged.
A literature search was performed with Ovid MEDLINE (1946–2016) using the terms ‘brittle’ and ‘diabetes mellitus’ as keywords. For each article, we reviewed the year of publication, phenotypic, pathophysiologic and psychosocial factors described in association with this term and author name/affiliation.
339 articles were included in analysis. 16 articles unrelated to DM were excluded. A proportion of articles were published by the same author (21%) and academic institution (7%) implying that over time, this term has been propagated by a small subdivision of the medical community. Since its initial description in 1938 as a subtype of DM, more recent definitions have incorporated a life-disruption component, recurrent hospitalisation and greater burden on health-care teams. Articles predominantly describe young females, type 1 diabetes, and eating disorders/psychiatric disease as key phenotypic features. Potential aetiologic factors have been described and include psychological illness (factitious, malingering), physiologic (malabsorption, gastroparesis) and non-physiologic factors (therapeutic error).
The term ‘brittle diabetes’ is ill-defined and over time, has taken on a range of different meanings and associations. It remains subjective as a clinical entity and although a part of common medical parlance, its use should be discouraged.