Youth with T1D often have poor glycemic control and compromised health and well-being. Our aim was to test the efficacy of the FLEX adaptive behavioral intervention on the primary (HbA1c) and secondary (psychosocial and metabolic) outcomes at 18 months.

Youth (n=258) aged 13-16 years, diagnosed >1 year with T1D with HbA1c from 8.0-13.0%, were randomized at two sites to FLEX or usual care control. Mean (sd) duration of diabetes was 6.4 (3.8) years, 50% were girls, 78% non-Hispanic white, mean HbA1c was 9.6% (1.2) and 71% used insulin pump therapy. FLEX used motivational interviewing and problem-solving skills training to enhance self-management. Intervention fidelity was assessed via random selection of audiotaped sessions for counseling strategy and session content. Intent-to-treat analyses used mixed effects models, with fixed effects of site, timepoint, intervention group, intervention by timepoint and baseline level of primary or secondary outcomes, with a random intercept (alpha=0.05).

Retention was 97%, with intervention fidelity 4.6 out of 5 for counseling strategy and 97.4% complete for session content. HbA1c was not statistically significantly different between intervention and control at 18 months. Among secondary outcomes at 18 months, the intervention was associated with improved scores for symptoms of depression (p=0.04), quality of life (p=0.01), motivation (p=0.009), problem-solving (p=0.04), and diabetes self-management profile (p=0.01), as well as better total cholesterol (p=0.04), and better diastolic blood pressure (p=0.01).

The FLEX intervention did not change the primary outcome, but did positively effect psychosocial outcomes over the 18 months of the trial. Further analyses will reveal information regarding drivers of positive response to the intervention and will point to directions for improvement in the approach, perhaps incorporating more specific direction towards achievement of glycemic targets.


E.J. Mayer-Davis: None. F.K. Bishop: None. K.A. Driscoll: None. C.M. Hunter: None. D.M. Maahs: Advisory Panel; Self; Insulet Corporation. Consultant; Self; Abbott. Research Support; Self; Medtronic, Bigfoot Biomedical, Dexcom, Inc., Insulet Corporation, Roche Diabetes Care Health and Digital Solutions. M. Seid: None. D. Standiford: None. J. Thomas: None.

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