Predictors of adherence with antihypertensive and lipid-lowering therapy. Chapman RH, Benner JS, Petrilla AA, et al. Arch Intern Med. 2005; 165:1147-1152.
Low adherence jeopardizing benefits of treating CV risk factors by Sue Hughes Heartwire May 26, 2005
Pertinent Points
1. Of 8406 patients prescribed both antihypertensives and lipid-lowering agents,
- 44.7% were adherent after 3 months
- 35.9% were adherent after 6 months
- 35.8% were adherent after 9 months
2. Patients were more likely to be adherent if they
- Were prescribed antihypertensives & lipid-lowering agents simultaneously
- Had a history of coronary heart disease or congestive heart failure
- Followed a regimen with fewer other medications
Parameters
1. The 8406 patients were followed for an average of 12.9 months.
2. Adherence was defined as patients filling prescriptions sufficient to cover at least 80% of days of both classes of medications.
Commentary
While there are few surprises found in the results of this study, it does provide further support for the notion that medication regimens with fewer prescribed agents are associated with better compliance. I have noted before, however, this concept, even if it is, as I suspect, accurate, may be of limited use in most situations that call for a prescription, given that few physicians routinely prescribe a complex regimen when prescribing a simpler set of medications is possible.
An exception that now comes to mind is the polypharmacy debate that erupts cyclically in various fields. In psychiatry, for example, the possibility that using multiple drugs in the treatment of bipolar, psychotic, or affective disorders provides benefits unattainable with single agents is a common topic in the literature and seminars and is even more frequently an issue in discussions held in the hallways of clinics and hospitals. If a reliable statistical relationship between compliance and regimen complexity can be established, adherence could – and should – be factored into those debates.
Another situation-specific use of the simpler regimen = better adherence formula could be as motivation for the primary clinician of a given patient to routinely and repeatedly assess that patient’s comprehensive medications list, regardless of who prescribed each agent, with the goal of eliminating unnecessary complexities.