Association and Familial Coaggregation of Type 1 Diabetes and Eating Disorders: A Register-Based Cohort Study in Denmark and Sweden
To ascertain the association and co-aggregation of eating disorders and childhood-onset type 1 diabetes in families.
RESEARCH DESIGN AND METHODS
Using population samples from national registers in Sweden (n= 2 517 277) and Demark (n= 1 825 920) we investigated the within-individual association between type 1 diabetes and EDs, and their familial co-aggregation among full siblings, half-siblings, full cousins, and half-cousins. Based on clinical diagnoses we classified eating disorders (EDs) into: any eating disorder (AED), anorexia nervosa and atypical anorexia nervosa (AN), and other eating disorder (OED). Associations were determined with hazard ratios (HR) with confidence intervals (CI) from Cox regressions.
RESULTS
Swedish and Danish individuals with a type 1 diabetes diagnosis had a greater risk of receiving an ED diagnosis (HR [95% CI] Sweden: AED 2.02 [1.80 – 2.27], AN 1.63 [1.36 – 1.96], OED 2.34 [2.07 – 2.63]; Denmark: AED 2.19 [1.84 – 2.61], AN 1.78 [1.36 – 2.33], OED 2.65 [2.20 – 3.21]). We also meta-analyzed the results: AED 2.07 [1.88 – 2.28], AN 1.68 [1.44 – 1.95], OED 2.44 [2.17 – 2.72]. There was an increased risk of receiving an ED diagnosis in full siblings in the Swedish cohort (AED 1.25 [1.07 – 1.46], AN 1.28 [1.04 – 1.57], OED 1.28 [1.07 – 1.52]), these results were non-significant in the Danish cohort.
CONCLUSION
Patients with 1 diabetes are at a higher risk of subsequent EDs; however, there is conflicting support for the relationship between having a sibling with type 1 diabetes and ED diagnosis. Diabetes healthcare teams should be vigilant for disordered eating behaviors in children and adolescents with type 1 diabetes.