Effectiveness of a two-part educational intervention to improve hypertension control: A cluster-randomized trial

Objective. To measure the effectiveness of a multifaceted educational intervention to improve ambulatory hypertension control. Design. Cluster-randomized trial. Setting. Academic health system using an ambulatory electronic medical record. Subjects. A total of 10,696 patients with a diagnosis of hypertension cared for by 93 primary care providers. Intervention. Academic detailing, provision of provider-specific data about hypertension control, provision of educational materials to the provider, and provision of educational and motivational materials to patients. Measurements and Main Results. The primary outcome was blood pressure control, defined as a blood pressure measurement below 140/90 mm Hg, and was ascertained from electronic medical records over 6 months of follow-up. We determined the adjusted odds ratio for the association between the intervention and the achievement of controlled blood pressure. When we accounted for clustering by provider, this adjusted odds ratio was 1.13 (95% confidence interval 0.87-1.47). Adjusted odds ratios were 1.03 (95% confidence interval 0.78-1.36) in patients whose blood pressure was controlled at baseline and 1.25 (95% confidence interval 0.94-1.65) in those whose blood pressure was not. These odds ratios were not significantly different (p=0.11). Conclusions. These results were consistent with no effect or, at best, a relatively modest effect of the intervention among patients with hypertension. Had we not included a concurrent control group, the data would have provided an unduly optimistic view of the effectiveness of the program. The effectiveness of future interventions may be improved by focusing on patients whose blood pressure is uncontrolled at baseline.