Comparative effectiveness of goal setting in diabetes mellitus group clinics: randomized clinical trial

Abstract

Background: Diabetes mellitus (DM) group clinics can effectively control hypertension, but data to support glycemic control are equivocal. This study evaluated the comparative effectiveness of 2 DM group clinic interventions on glycosylated hemoglobin (HbA(1c)) levels in primary care.

Methods: Eighty-seven participants were recruited from a DM registry of a single regional Veterans Affairs medical center to participate in an open, randomized comparative effectiveness study. Two primary care-based DM group interventions of 3 months' duration were compared. Empowering Patients in Care (EPIC) was a clinician-led, patient-centered group clinic consisting of 4 sessions on setting self-management action plans (diet, exercise, home monitoring, medications, etc) and communicating about progress with action plans. The comparison intervention consisted of group education sessions with a DM educator and dietician followed by an additional visit with one's primary care provider. Hemoglobin A(1c) levels were compared after intervention and at the 1-year follow-up.

Results: Participants in the EPIC intervention had significantly greater improvements in HbA(1c) levels immediately following the active intervention (8.86%-8.04% vs 8.74%-8.70% of total hemoglobin; mean [SD] between-group difference 0.67% [1.3%]; P=.03), and these differences persisted at the 1 year follow-up (0.59% [1.4%], P=.05). A repeated-measures analysis using all study time points found a significant time-by-treatment interaction effect on HbA(1c) levels favoring the EPIC intervention (F(2,85)=3.55; P=.03). The effect of the time-by-treatment interaction seems to be partially mediated by DM self-efficacy (F(1,85)=10.39; P=.002).

Conclusion: Primary care-based DM group clinics that include structured goal-setting approaches to self-management can significantly improve HbA(1c) levels after intervention and maintain improvements for 1 year. Trial Registration clinicaltrials.gov Identifier: NCT00481286.

Figure 1. Intervention group description

DM indicates diabetes mellitus, PCP indicates primary care provider

Figure 2. Study design and participant flowchart

EPIC indicates Empowering Patients in Care; VA Veterans Affairs.

Figure 3. Longitudinal change in Hemoglobin A_1c by intervention group

Each data point represents the mean and standard error values for all patients (n=85) at each data collection time point. Using a repeated measures analysis, the overall effect of the interaction of intervention group by time was significant (F_(2,85)= 3.55, P= .03) on longitudinal Hemoglobin A1c values.