Adherence (compliance) is the degree to which a patient follows a treatment regimen. For medications, adherence requires that the prescription be obtained promptly and the medication be taken as prescribed in terms of dose, dosing interval, duration of treatment, and any additional special instructions (eg, taking the medication without food). Patients should be told to alert their physician if they stop or alter the way they take a medication.
Only approximately half of patients who leave a physician’s office with a prescription take the medication as directed. The most common reasons for nonadherence are
Frequent dosing
Denial of illness
Poor comprehension of the benefits of taking the medication
Cost of medication
Many other reasons contribute to nonadherence (see table Causes of Nonadherence).
Causes of Nonadherence
Source | Cause |
|---|---|
Patient | Apathy Concern about taking medications (eg, adverse effects, addiction) Denial of the disorder or its significance Financial concerns Forgetfulness Misunderstanding of prescribing instructions No faith in the medication’s efficacy Physical difficulties (eg, with swallowing tablets or capsules, opening bottles, or obtaining prescriptions) Reduction, fluctuation, or disappearance of symptoms |
Medication | Adverse effects (real or perceived) Complex regimen (eg, frequent dosing, many medications) Inconvenient or restrictive precautions (eg, no alcohol or cheese) Similar appearance of medications Unpleasant taste or smell |
Children are less likely than adults to adhere to a treatment regimen. Adherence is worst with chronic disorders requiring complex, long-term treatment (eg, asthma). Parents may not clearly understand prescription instructions or may forget some of the information given by the physician.
Older adults adhere to treatment regimens as well as other adults. However, factors that decrease adherence (eg, inadequate finances, use of multiple medications or medications that must be taken several times a day) are more common among older adults (see Drug-Related Problems in Older Adults: Lack of patient adherence). Cognitive impairment may further decrease adherence.
The most obvious result of nonadherence is that the disorder may not be relieved or cured. Nonadherence is estimated to result in 125,000 deaths due to cardiovascular disorders each year in the United States. When patients take their medications as directed, up to 23% of nursing home admissions, 10% of hospital admissions, many physician visits, many diagnostic tests, and many unnecessary treatments can be avoided. In some cases, nonadherence can actually lead to worsening of disease. For example, missed doses or early cessation of antibiotic or antiviral therapy may lead to resistant organisms.
Health care professionals may detect and help solve adherence problems. Health care professionals should ask a patient how often they miss their medications. A pharmacist may note that a patient does not obtain refills or that a prescription is being refilled too soon. The pharmacist could ask the patient, “When was the last time you took your medicine?" In reviewing prescription directions with the patient, a pharmacist may uncover a patient’s misunderstandings or fears and alleviate them. Pharmacists or other professionals can recommend less complicated or less frequent dosing or substitute safe, effective, or less expensive medications. Good communication among the patient and all the health care professionals that provide care for that patient is important.
