American Heart Journal
Volume 158, Issue 4 , Pages 506-508, October 2009

The high cost of nonadherence after percutaneous coronary intervention—Can health care reform solve this problem?

Division of Cardiovascular Medicine, Gill Heart Institute, University of Kentucky, Lexington, KY

Received 7 July 2009; accepted 13 July 2009. published online 24 August 2009.

Article Outline

 

Dual antiplatelet therapy is a pivotal component of the management in patients undergoing percutaneous coronary intervention (PCI). Accordingly, recent practice guidelines recommend 12 months of dual antiplatelet therapy after implantation of a drug-eluting stent (DES).1 Despite such recommendations, several studies have reported a significant degree of nonadherence to thienopyridine therapy after PCI.2 The consequences of nonadherence to medications in general translate into significantly increased usage of expensive health care services, including emergency department visits and hospitalizations. In fact, poor adherence has been estimated to cost approximately $177 billion annually in total direct and indirect health care costs.3 With respect to thienopyridine specifically, nonadherence or premature discontinuation is associated with a marked increase in the risk of stent thrombosis (resulting in myocardial infarction and/or death) and is the leading independent predictor of stent thrombosis.4

In this issue of the journal, Ko et al5 evaluated 12-month patterns of thienopyridine therapy use after PCI and factors associated with suboptimal medication adherence. The authors report that suboptimal adherence after DES implantation was strongly associated with an increased mortality risk. The study provides vital information on the importance of adherence to dual antiplatelet therapy after PCI. Another key message from this study is that patients who received thienopyridine medication at significantly reduced rates were more than 70% likely to fill their initial prescription. This finding may have health policy implications.

A minor limitation of the study by Ko et al is the use of pharmacy refill records for assessing adherence. Granted, under the best of circumstances, adherence is difficult to measure. Direct measures are the most accurate means to assess adherence. Direct methods include measuring concentrations of a drug or its metabolite in blood or urine, and similar detection or measurement of a biologic marker added to the medication.6 However, direct approaches are expensive and cumbersome. Indirect methods of measurement of adherence include asking the patient, assessing clinical response, performing pill counts, ascertaining rates of refilling prescriptions, collecting patient questionnaires, using electronic medication monitors, and asking the patient to keep a medication diary. Questioning the patient is the easiest method to assess adherence but tends to result in overestimating the patient's adherence because patients may not like to admit to nonadherence.6 Rates of refilling prescriptions, as was used in this study, are a reasonable and accurate measure of overall adherence in a closed pharmacy system such as the Ontario drug benefit prescription claims database, provided that the refills are measured at several points temporally.7

Barriers for optimal adherence of therapies include financial concerns, perceived adverse effects, need for multiple medications (very common in patients with coronary artery disease), multiple daily dosing, insufficient access to physicians, and in some cases, physicians' lack of knowledge about the disease and the value of guideline-recommended care.8 Improving adherence has been difficult to study, and adherence rates have typically not been improved by simple interventions. Successful interventions to improve adherence need to be multipronged and simultaneously address a number of barriers to adherence.9

Interventions that may successfully improve adherence may include minimizing or eliminating drug costs, patient education and empowerment, patient reminders, frequent clinic visits, or telephone calls from staff or physicians. Every attempt should be made to simplify the patient's drug regimen by reducing the number of pills per day and by minimizing medication costs wherever possible by prescribing generic medications. Direct counseling of patients by pharmacists may be particularly promising because of pharmacists' specialized training and knowledge of medications and availability to patients. The effectiveness of pharmacist intervention was demonstrated by Lee et al.10 In this study, a pharmacy care program led to increases in medication adherence, medication persistence, and clinically meaningful reductions in blood pressure (BP), whereas discontinuation of the program was associated with decreased medication adherence and persistence. Medication therapy management should be part of any comprehensive healthcare reform plan.

Nonadherence will need to be attacked from multiple levels. Every improvement in medication adherence at the individual level will contribute to a societal-level impact. As clinicians, we need to make every attempt to keep the number of medications and daily doses to a minimum and empower and educate our patients on the importance of complying with prescribed therapies. In addition, we should prescribe generic drugs whenever possible because generics are less expensive and current evidence does not suggest superiority of brand-name drugs.11

The National Conference of Pharmaceutical Organizations recommended in their policy statement on national health care reform that every American should have access to the most appropriate clinically effective medications and counseling on the importance of proper medication use (Table I).

Table I. National Conference of Pharmaceutical Organizations recommendations for the National Healthcare Reform Agenda3
• Every American should have access to the most appropriate clinically effective medications, as well as counseling on proper medication use and the importance of adherence to medication.
• National goals for the improvement of health care quality should include evaluating provider performance through measurement, public reporting of quality measures, and providing incentives for improving patient outcomes.
• Health systems focused on coordinated care should be available to all patients with access to a care coordinator who can help them manage their health effectively and ensure compliance with prescription drug therapy.
• Fair reimbursement to health care providers should include costs related to dispensing medications and pharmacist-provided care, such as medication therapy management. Providing services such as medication therapy management is especially important to patients with chronic disease because chronic diseases are the number one cause of death and disability in the United States, and treating patients with chronic conditions accounts for 75% of the nation's health care spending.
• Health information technology, including electronic prescribing and electronic medical records, should be incorporated and used appropriately by providers to improve patient health outcomes, coordinate patient care, and aid in appropriate health research.
• Preventive services such as healthcare screenings and immunizations, medication therapy management, and disease management should be covered and promoted through outreach and education for optimal utilization.
• Behaviors that promote health and wellness should be encouraged.

Policymakers may help by eliminating copayments for essential medications such as thienopyridine, statins, β-blockers, and angiotensin-converting enzyme inhibitors. The cost of such policy will be more than offset by reducing expensive rehospitalizations and emergency department visits.

At the national level, as Congress contemplates healthcare reform this year, it is essential that they focus on quality of care, including measures to improve adherence to prescribed medications.

Medication nonadherence is expensive for our society, and unfortunately, it is common.12 Of all medication-related hospital admissions in the United States, 33% to 69% are due to poor medication adherence, with a resultant cost of more than $100 billion a year.6 We need to develop effective ways to address medication nonadherence, and strategies will need to include a multilevel approach including patients, physicians and other allied health care professionals, pharmacists, insurers, and policymakers.

Efforts to use financial incentives or disincentives to improve adherence to essential medications is a strategy that needs additional study. Potential incentives may include lowering insurance premiums for patients who adhere to therapy; disincentives may include higher premiums or loss of some benefits for patients who are persistently nonadherent. Although such incentives are likely to be effective, financial disincentives are likely to be resisted by many groups and organizations. Another possible approach for DES patients may be to incorporate the cost of 12 months of dual antiplatelet therapy into the charge for the initial PCI procedure. The medication could then be provided free to the patient at the time of the discharge. For patients who are not expected to comply with 12 months of thienopyridine therapy, whether for economic or other reasons, strong consideration should be given to avoiding a DES.

The almost universal availability of the Internet, smart phones, and information support systems may eventually open up new and more effective ways to communicate with our patients and further improve adherence. The large amount of resources spent to improve physician compliance with guidelines and prescribing of optimal therapies will continue to be ineffective unless we can improve adherence to prescribed therapies. Finally, although a wide range of adherence aids and strategies are currently available, the key to success will be to tailor the intervention to the individual patient and, when necessary, to combine multiple interventions to optimize adherence. Addressing the financial barrier as suggested by the study by Ko will likely help improve adherence but is unlikely to eliminate the problem completely.

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References 

  1. Grines CL, Bonow RO, Casey DE, et al. Prevention of premature discontinuation of dual antiplatelet therapy in patients with coronary artery stents: a science advisory from the American Heart Association, American College of Cardiology, Society for Cardiovascular Angiography and Interventions, American College of Surgeons, and American Dental Association, with representation from the American College of Physicians. Circulation. 2007;115:813–818
  2. Pallares MJ, Powers ER, Zwerner PL, et al. Barriers to clopidogrel adherence following placement of drug-eluting stents. Ann Pharmacother. 2009;43:259–267
  3. Policy Statement On Healthcare Reform, Its implementation, and Future Innovations, May 28, 2009: National Conference of Pharmaceutical Organizations; 2009.
  4. Cross J. Antiplatelet therapy for improving post-PCI outcomes: interpreting current treatment guidelines for optimal management of the post-ACS patient. Am J Manag Care. 2009;15(2 Suppl):S48–S53
  5. Ko D, Chiu M, Guo H, et al. Patterns of use of thienopyridine therapy after percutaneous coronary interventions with drug-eluting stents and bare-metal stents. Am Heart J. 2009;158:592–598
  6. Osterberg L, Blaschke T. Adherence to medication. N Engl J Med. 2005;353:487–497
  7. Steiner JF, Prochazka AV. The assessment of refill compliance using pharmacy records: methods, validity, and applications. J Clin Epidemiol. 1997;50:105–116
  8. Simpson RJ. Challenges for improving medication adherence. JAMA. 2006;296:2614–2616
  9. Mukherjee D. Improving adherence to medications—can we make this horse drink?. Am Heart J. 2008;155:589–590
  10. Lee JK, Grace KA, Taylor AJ. Effect of a pharmacy care program on medication adherence and persistence, blood pressure, and low-density lipoprotein cholesterol: a randomized controlled trial. JAMA. 2006;296:2563–2571
  11. Kesselheim AS, Misono AS, Lee JL, et al. Clinical equivalence of generic and brand-name drugs used in cardiovascular disease: a systematic review and meta-analysis. JAMA. 2008;300:2514–2526
  12. O'Connor PJ. Improving medication adherence: challenges for physicians, payers, and policy makers. Arch Intern Med. 2006;166:1802–1804

PII: S0002-8703(09)00544-4

doi:10.1016/j.ahj.2009.07.007

Refers to article:

  • Patterns of use of thienopyridine therapy after percutaneous coronary interventions with drug-eluting stents and bare-metal stents , 24 August 2009

    Dennis T. Ko, Maria Chiu, Helen Guo, Peter C. Austin, Jean-François Marquis, Jack V. Tu
    American Heart Journal October 2009 (Vol. 158, Issue 4, Pages 592-598.e1)

American Heart Journal
Volume 158, Issue 4 , Pages 506-508, October 2009

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