The Benefits and Risks of Adherence to Medical Therapy

Abstract

Noncompliance or nonadherence to prescribed medication is common. Reasons given by patients for not taking medications as prescribed include cost, adverse effects, or perceived lack of effectiveness, all of which are important factors in shared decision-making between health care providers and patients. It has been assumed that better compliance with medication therapy would mean better control of disease, prevention of disease-associated health impairment, and cost savings, but these assumptions are questionable. Although adherence to some medications, including anti-tuberculosis drugs and oral contraception, is necessary for effectiveness, it is unclear whether adherence to many other medications improves outcomes. Patients who adhere to almost any medication, including placebo, have better health outcomes, but these benefits could be due to healthy behaviors for which adherence is a marker. On the other hand, compliance with treatments that are harmful increase harms. Efforts to increase compliance with new drugs may be risky because newer drugs have limited safety data. We recommend that practitioners use noncompliance as an opportunity to address problems identified by the patient, including medication cost, side effects, and lack of perceived benefits. We also argue that inadequate attention has been paid to the possible role of drug manufacturers in distorting information about the causes, benefits, and harms of adherence.