Effectiveness of disease-management programs for improving diabetes care: a meta-analysis

Background

We conducted a meta-analysis of randomized controlled trials to assess the effectiveness of disease-management programs for improving glycemic control in adults with diabetes mellitus and to study which components of programs are associated with their effectiveness.

Methods

We searched several databases for studies published up to December 2009. We included randomized controlled trials involving adults with type 1 or 2 diabetes that evaluated the effect of disease-management programs on glycated hemoglobin (hemoglobin A_1C) concentrations. We performed a meta-regression analysis to determine the effective components of the programs.

Results

We included 41 randomized controlled trials in our review. Across these trials, disease-management programs resulted in a significant reduction in hemoglobin A_1C levels (pooled standardized mean difference between intervention and control groups −0.38 95% confidence interval −0.47 to −0.29], which corresponds to an absolute mean difference of 0.51%). The finding was robust in the sensitivity analyses based on quality assessment. Programs in which the disease manager was able to start or modify treatment with or without prior approval from the primary care physician resulted in a greater improvement in hemoglobin A_1C levels (standardized mean difference −0.60 v. −0.28 in trials with no approval to do so; p < 0.001). Programs with a moderate or high frequency of contact reported a significant reduction in hemoglobin A_1C levels compared with usual care; nevertheless, only programs with a high frequency of contact led to a significantly greater reduction compared with low-frequency contact programs (standardized mean difference −0.56 v. −0.30, p = 0.03).

Interpretation

Disease-management programs had a clinically moderate but significant impact on hemoglobin A_1C levels among adults with diabetes. Effective components of programs were a high frequency of patient contact and the ability for disease managers to adjust treatment with or without prior physician approval.Despite well-established recommendations for diabetes care,^1–3 quality of care still needs to be improved. Although many nonpharmacologic strategies (patient education, psychological intervention, dietary education, self-monitoring and telemedicine) have been developed, their effectiveness is still unclear.^4–6 “Disease management” is a structured, multi-faceted intervention that includes several of the above-mentioned components. In two recent meta-analyses, disease management was associated with an improvement in glycemic control, as assessed by a mean reduction in hemoglobin A_1C concentration of 0.52% and 0.81%.^7,8 Disease management seems to be more effective than single strategies such as clinician education, patient education or promotion of self-management.⁷Because disease-management programs are heterogeneous, the effective components need to be identified to improve program implementation. Previous studies have evaluated the efficacy of some program components.^7,8 Independent medication changes by the disease manager appear to be particularly effective.⁷ However, other important factors such as the intensity of the intervention have not been previously evaluated.We conducted a meta-analysis of randomized controlled trials (RCTs) involving adults with type 1 or 2 diabetes mellitus that evaluated the effect of disease-management programs on hemoglobin A_1C levels. We determined the effective components of the programs, considering both the type of component and the intensity of the intervention.