Skip to main content

Poor Adherence Rates among Patients with Mental Illness

Authors

Tim Casey

Orlando—Although patients with mental illness are typically prescribed medications, adherence is a major issue, as more than half of patients in some cases do not take their medications as advised. However, they are more likely to adhere to doctors’ orders if they believe physicians are competent, approachable, and interested in them, according to a panel of healthcare professionals who spoke during a session at Psych Congress.

Rakesh Jain, MD, MPH, clinical professor, department of psychiatry, Texas Tech Health Sciences Center School of Medicine, discussed a community-based health survey of 6201 patients that found the nonadherence rates were 34.6% for antipsychotics, 34.7% for sedative hypnotics, 38.1% for anxiolytics, 44.9% for mood stabilizers, and 45.9% for antidepressants [Soc Psychiatry Psychiatr Epidemiol. 2010;45(1):47-56].

Factors for Nonadherence
Other studies have found that nonadherence rates were 40% to 60% for antipsychotics, 18% to 56% for mood stabilizers, and 30% to 97% for antidepressants. Furthermore, nonadherence rates were 28% to 52% for patients with major depressive disorder, 20% to 50% for patients with bipolar disorder, 20% to 72% for patients with schizophrenia, and 57% for patients with an anxiety disorder.

According to a study, the following were the most common reasons for medication nonadherence [N Engl J Med. 2005;353(5):487-497]:
• Forgetfulness (30%)
• Other priorities (16%)
• Decision to omit doses (11%)
• Lack of information (9%)
• Emotional factors (7%)

Another study found that medically ill patients who had psychiatric illnesses were prone to nonadherence [Int J Geriatr Psychiatry. 2008;23(5):447-453]. Of the depressed patients in the study, 14% did not take their medications as prescribed compared with 5% of patients who were not depressed. Meanwhile, 18% of depressed and 9% of nondepressed patients, respectively, forgot to take their medications, while 9% and 4%, respectively, decided to stop taking their medications.

There are numerous predictors of poor medication adherence, according to Dr. Jain, including:
• Poor provider–patient relationship
• Psychological problems
• Cognitive impairment
• Medication adverse effects
• Inadequate follow-up or discharge planning
• Lack of health literacy
• Barriers to care
• Lack of insight into illness
• Cost of medications
• Cost of copayments
• Treatment complexity
• Cultural, health, and/or religious beliefs
• Lack of social support
• Forgetfulness
• Missed appointments
• Lack of belief in the benefit of treatment

Dr. Jain added that medication-related barriers to adherence include:
• Polypharmacy
• Drug packaging
• Route of administration
• Drug formulation
• Dosing frequency
• Adverse effects
• Dose strength
In addition, patient-related barriers to adherence include:
• History of adherence
• Comorbid substance abuse
• Illness beliefs
• Financial barriers
• Insight
• Cognitive deficits
• Chronic illness
• Sociodemographics
• Psychopathology (ie, hostility, suspiciousness, disorganization)

Patient–Clinician Relationship
W. Clay Jackson, MD, assistant professor, family medicine and psychiatry, University of Tennessee College of Medicine, said patients with chronic diseases take their medications as prescribed 50% to 60% of the time. He noted that adherence could increase if patients and clinicians communicate and work together.

Dr. Jackson quoted Shawn Shea, MD, author, Improving Medication Adherence: How to Talk with Patients About Their Medications, who wrote, “Resistance is not so much a behavior that [1] person does, as it is an experience that [2] people share.” Dr. Jackson also quoted former US Surgeon General C. Everett Koop, MD, who said, “Our patients reach for their pill bottles, unscrew their caps, and reap the benefits of our medications almost purely because of the power of their bond with us.”

A study of 3926 patients in 150 rural counties in the southeastern United States found that 21.6% of patients had primary nonadherence [J Am Board Fam Med. 2006;19(5):478-486]. The physician-associated risk factors for primary nonadherence were lack of confidence in the doctor’s ability to help, lack of satisfaction with the amount of concern the physician showed, and lack of satisfaction with how welcome and comfortable patients were made to feel by the physician’s office staff.

Even for experienced physicians, it is difficult to determine whether patients are nonadherent, according to Dr. Jackson. He cited a study that found 34% of bipolar patients were nonadherent, though psychiatrists only deemed 6% of the patients nonadherent [Hum Psychopharmacol. 2008;23(2):95-105]. He added that some reasons that physicians and healthcare professionals have trouble assessing adherence include time and effort are required to gather information, the assessment may not lead to complete information, and they may not have been given accurate information.

To increase adherence for patients with antidepressants, Dr. Jackson suggested primary care physicians speak with patients about how to take the medications, discuss the short-term and long-term expected effects of the medication, explain how the medication works, and emphasize that antidepressants are not addictive.

Dr. Jackson said studies of patients with chronic and serious conditions have proven the importance of consistent communication between physicians and patients.

A study of 554 patients with HIV found the following characteristics of physicians were statistically significantly associated with increased patient adherence [J Gen Intern Med. 2004;19(11):1096-1103]:
• General communication
• Disease-specific communication
• Adherence dialogue
• Overall satisfaction
• Patient willingness to recommend the physician
• Physician’s trust

Another study found that for patients with schizophrenia, the most important predictor of adherence was their perception of their physicians’ interest in them [Am J Hosp Pharm. 1975;32(12):1237-1242]. Patients who consented to appointments and prescriptions were more satisfied with the ward staff and attending physicians and believed that physicians understood them, had their best interests in mind, explained the reasons for medications, and explained potential adverse events.

Finally, Dr. Jackson mentioned a study that found of the patients who rated their alliance with therapists as “good” after 6 months, 26% were nonadherent in the next 18 months compared with a 74% nonadherence rate for patients who rated their alliance with therapists as “poor” or “fair” after 6 months [Arch Gen Psychiatry. 1990;47(3):228-236].

Online Resources for Medication Adherence
Saundra Jain, PsyD, executive director, Mental Aerobics Project, Austin, Texas, said healthcare professionals frequently ask patients about their adherence to medications and problems they are having or anticipate having with their medications [J Clin Psychiatry. 2009;70(suppl 4):1-48]. However, Dr. Jain noted that they rarely obtain plasma levels of medications, review pharmacy refill records, use standardized instruments such as the Brief Adherence Rating Scale, or use technological tools such as smart pill containers.

Applications on smartphones and tablets as well as Web sites are helpful at improving medication adherence, according to Dr. Jain. She mentioned Adult Meducation: Improving Medication Adherence in Older Adults, an online program that informs members of the American Society on Aging and the American Society of Consultant Pharmacists Foundation of the importance of medication adherence for older adults.—Tim Casey

Back to Top