Body mass index moderates the association between diabetes distress and objective self-management behaviours in adolescents with type 1 diabetes and elevated A1Cs.

OBJECTIVE:To examine the cross-sectional associations between diabetes distress, BMI (zBMI; BMI z-score), objectively measured mean daily blood glucose readings and insulin boluses administered, and A1C in adolescents with type 1 diabetes (T1D) using insulin pumps. METHODS:T1D self-management behaviour data were downloaded from adolescents' (N = 79) devices and mean daily frequency of blood glucose readings and insulin boluses were calculated. Diabetes distress was measured (Problem Areas in Diabetes-Teen questionnaire [PAID-T]), A1C collected, and zBMI calculated from height and weight. Three multiple linear regressions were performed with blood glucose readings, insulin boluses, and A1C as the three dependent variables and covariates (age, T1D duration), zBMI, diabetes distress, and the diabetes distress x zBMI interaction as independent variables. RESULTS:Participants (55.7% female) were 14.9 ± 1.9 years old with T1D for 6.6 ± 3.4 years. zBMI moderated the relationship between diabetes distress and mean daily insulin boluses administered (b = -0.02, p = 0.02); those with higher zBMI and higher diabetes distress administered fewer daily insulin boluses. zBMI was not a moderator of the association between diabetes distress and blood glucose readings (b = -0.01, p = 0.29) or A1C (b = 0.002, p = 0.81). CONCLUSIONS:Using objective behavioural data is useful for identifying how adolescent diabetes distress and zBMI affect daily bolusing behaviour amongst adolescent insulin pump users. Although distinct interventions exist to improve T1D self-management or diabetes distress, none addresses them together while considering zBMI. Decreasing diabetes distress could be especially important for youth with high zBMI.