Association of eating disorders and/or insulin omission with impaired glycaemic control in persons living with type 1 diabetes: cross-sectional analysis of the French SFDT1 study

ObjectiveTo address whether eating disorders (ED) or insulin omission (IOM) in adult persons living with type 1 diabetes (pwT1D) are associated with impaired glycaemic control.DesignCross-sectional analysis.SettingsThe French-Speaking Diabetes Society—Type 1 Diabetes Cohort (SFDT1) is an ongoing epidemiological cohort study that includes pwT1D in France who attend hospitals or private ambulatory diabetes centres.ParticipantsAdult participants from the SFDT1 study, with data on ED and IOM. The current analysis was performed on data collected during the baseline visit in participants enrolled between December 2020 and March 2024.Main outcome measuresUsing the SCOFF, a self-reported questionnaire to screen for ED, and a single question on IOM to screen for IOM, we described four categories of pwT1D: no ED & no IOM, ED & no IOM, no ED & IOM and ED & IOM. We performed unadjusted and adjusted (for age, sex, diabetes duration, social vulnerability, smoking, alcohol status and insulin treatment) multinomial logistic regression models with the four categories as the outcome and glycaemic variables as explanatory variables, including continuous glucose monitoring (CGM) variables and HbA1c. No ED & no IOM was the reference outcome for all comparisons. We stratified each model by sex and fear of hypoglycaemia.ResultsWe included 1113 participants, 51% males, median (IQR) age 38 (29–50) years, diabetes duration 21 (12–32) years. Prevalences were as follows: no ED & no IOM: 68% (n=758), ED & no IOM: 11% (n=124), no ED & IOM: 16% (n=177) and ED & IOM: 5% (n=54). With the fully adjusted model, and compared with the group no ED & no IOM, time in range (OR (95% CI) 0.5 (0.4 to 0.7)) and time below range (0.5 (0.3 to 0.8)) were inversely associated with ED & IOM. Moreover, time in range (0.4 (0.4 to 0.5)) was associated with IOM & no ED. Time above range (2.2 (1.6 to 2.9)), Glycaemic Risk Index (1.8 (1.3 to 2.5)), glucose monitoring indicator (2.2 (1.7 to 2.9)) and HbA1c (2.0 (1.5 to 2.5)) were directly associated with ED & IOM. We did not observe associations between CGM variables and ED & no IOM. Most associations were valid in both men and women. The associations were stronger in participants with a fear of hypoglycaemia. However, the associations remained even in people with a fear of hypoglycaemia.ConclusionsBoth ED and IOM are frequent in pwT1D, and IOM seems to be associated with impaired glycaemic control. As our analysis was cross-sectional, we cannot infer causality and cannot know whether IOM was a result of glycaemic control or the inverse (reverse causality). Our results suggest that IOM should be systematically screened in clinical practice. Further research is needed to better identify and care for EDs, with or without IOM, in T1D.Trial registration numberNCT04657783.