The Effect of Antihypertensive Therapy on Medication Adherence and Blood Pressure Control – A Quality Improvement Project

Purpose: The purpose of this quality improvement project was to compare fixed dose medication combination (FDCT) and mixed dose medication combination antihypertensive therapy (MDCT) on medication adherence and blood pressure (BP) in a small sample of patients with hypertension in a rural clinic in West Tennessee.

Method: Sixty study participants were recruited from a rural internal medicine practice in Brownsville, Tennessee. Thirty participants were taking FDCT and thirty participants were taking MDCT. Medication adherence and BP were measured to determine the relationships between type of antihypertensive therapy (FDCT compared to MDCT) and the outcome variables. Analysis: Chi-square analyses, Analyses of variance (ANOVA), Two-tailed, independent samples t-tests were used to evaluate differences between scores on the Morisky Adherence Scale – 8 and BP. A Pearson product-moment correlation was conducted to determine the relationship between adherence and blood pressure. All analyses were performed using IBM SPSS 26 (Armonk, NY). The a priori alpha level of 0.05 was used to test for significance.

Results: There were no statistical difference between the two groups in medication adherence scores or BP based on antihypertensive therapy. Age was the only demographic variable found to have a significant correlation with BP. The effect of a relatively small sample size and other factors not studied may have affected the overall results. Conclusion: This study did not find that medication adherence differed by type of antihypertensive regimen prescribed among the study participants.