HbA1c (You Later)—What Happens to Glycemic Control while Waiting for NICH?

Objective: Novel Interventions in Children’s Healthcare (NICH) is a community-based, family-focused intervention for youth with T1D who experience self-management difficulty due to social challenges. Previous findings suggest that NICH participation is associated with improved glycemic control. However, conclusions are limited due to possibility that these outcomes are influenced by regression to the mean and not reflective of intervention effect. This study examines whether glycemic control regresses during wait period following referral to NICH.

Methods: Youth with T1D and consistently poor glycemic control were referred to NICH and experienced a wait based on insurance approval and program capacity. Retrospective chart reviews collected HbA1c values in the year prior to referral, during wait period, and during NICH. Thirty-nine youth had lab values for all three time periods. Youth mean age was 15.4 years; 56% were female; and 85% were Caucasian. Mean days prior to referral, on wait list, and during NICH were 365, 161, and 394 days, respectively.

Results: Average youth HbA1c remained relatively stable during the wait-period (t(38)=.509, p=.61), going from 11.6 (SD=1.5) to 11.5 (SD=1.6). Average youth glycemic control significantly decreased to 10.9 (SD=1.6) during NICH intervention compared to prior to referral (t(38)=2.31, p=.03) and during wait period (t(38)=2.30, p=.03).

Conclusions: Youth glycemic control while waiting for NICH remained stable and high, only demonstrating significant and clinically meaningful improvement during NICH involvement.These findings suggest that, while regression to the mean should always be considered as a threat to validity, it may not apply to youth who have a history of significantly elevated A1cs. Thus, improvements experienced by these youth likely represent change associated with their involvement in NICH, and longer waits to access a program like NICH likely increase risk of short- and long-term diabetes complications.