Evaluation of Administration Time and Adherence Rates of Morning vs. Bedtime Dosing of Antihypertensive Medications

Purpose The primary objective of this study was to evaluate the time of day patients administer antihypertensive medications. Secondary objectives were to evaluate medication adherence rates between morning and bedtime dosing and possible barriers to bedtime administration. Methods A single-center, cross-sectional study using a mixed-methods model containing a retrospective chart review and telephone survey was administered to hypertensive patients at a multidisciplinary, private practice clinic. Patients above the age of 18 with a diagnosis of hypertension were eligible for inclusion. The primary endpoint was the number of patients administering one or more antihypertensive medications at bedtime. Secondary endpoints were medication adherence and potential barriers of adherence to bedtime dosing. Results A total of 139 responses were collected. Most patients (75.5%) administered all antihypertensive medications in the morning, with only 24.5% of patients administering at least one antihypertensive medication at bedtime. Adherence was higher for medications administered in the morning compared to medications administered at bedtime, 87.8% and 79.4%, respectively. Limitations to this study include the single-center design and potential for patient recall and reporting bias when using self-reported data. Conclusion Results of this study suggest that the prevalence of bedtime administration of antihypertensive medications is low. Although self-reported adherence rates were higher with morning dosing compared to bedtime dosing, adherence rates for bedtime dosing were still promising. Future studies should be conducted to expand on existing morbidity and mortality evidence as well as prevalence of and adherence to bedtime dosing of antihypertensive medications.