Negative impact of physician prescribed drug dosing schedule requirements on patient adherence to cardiovascular drugs.

PURPOSE: The aim of this study was to determine whether dosing schedule requirements impair overall cardiovascular drug adherence.

METHODS: A cohort study was performed with hospitalized patients at high risk of cardiovascular disease between April and September 2011. Patients were asked whether the prescribed time for taking their statin and antiplatelet drugs created any inconvenience in their daily routine and, if so, were asked to describe the reasons. Patient adherence to treatment was assessed using the Morisky Medication Adherence Scale (MMAS-8). A cohort of physicians was separately studied between June and September 2011. Physicians were interviewed to determine their dosing schedule preference when prescribing statin and anti-platelet drugs, and the rationale for choosing a specific dosing schedule.

RESULTS: In the study, 103 patients and 59 physicians were included. Statins were most frequently prescribed in the evening (90%). Thienopyridines were prescribed both at lunch time (41%) and in the morning (35%). Aspirin was most frequently (65.3%) prescribed at lunch time. In total, 24.3% of patients reported being inconvenienced by their drug dosing schedule, and these subjects were less adherent to their drug regimen than those who did not report inconvenience (46.2% versus 16.7%, p = 0.014). Our results also demonstrate that there is no pharmacologic rationale for prescribing a particular drug dosing schedule for statin or anti-platelet drugs.

CONCLUSIONS: Physicians should assess patient convenience, when prescribing medication, to optimize treatment adherence.