Medication-related errors jeopardize patient safety and commonly result in otherwise unnecessary hospitalizations. Approximately 7% of hospital admissions result from drug-related errors, of which 59% are considered preventable.1 It is estimated that adverse drug events affect 2% to 5% of hospitalized patients.2,3 These errors result in increased hospital costs of $4,700 per admission, or about $2 billion annually for U.S. hospitals.2 Calculations indicate that in the nursing home, for each dollar spent on a medication, there is another $1.33 spent on healthcare resources for the treatment of a drug-related morbidity or mortality.
Unfortunately, older folks are particularly susceptible to medication-related problems. Age-associated changes in body composition and physiology, multiple comorbidities, and—last but not least—polypharmacy, are contributing factors. In the United States, patients older than 65 fill an average of 12 prescriptions per year, compared with five fills for patients between ages 25 and 40. In addition, the use of nonprescription medications is more common in the elderly. This opens up the possibility of increased drug-drug or drug-herbal interactions.
Depending on the healthcare setting, as well as the criteria that define inappropriate medication use, studies alert us that between 7% and 21% of ambulatory older folks receive at least one potentially inappropriate medication.4,5 About 60% of nursing home residents, and a staggering 92% of frail elderly hospitalized veterans, receive at least one potentially inappropriate medication.6,7 The consequences of inappropriate drug use in the elderly can be significant. Weakness, resulting in loss of independence and falls that end in bone fractures, is only one possible negative consequence. Between 10% and 20% of the elderly are hospitalized as a result of receiving these inappropriate medications.8,9
Screening Inappropriate Medication
So, what are inappropriate medications for the elderly? Overly simplified, they include any medication that has a greater potential for doing more harm than good. In 1991, Beers and colleagues published criteria for screening inappropriate medication use in elderly patients.10 The authors reviewed the literature and identified 14 nationally recognized authorities in the fields of geriatric pharmacology, epidemiology, geriatrics, and long-term care. Among these experts, consensus was reached on a list of inappropriate medications for elderly nursing home residents. The list was intended to identify medications that should be avoided except under unusual circumstances. The experts also developed criteria for optimal doses, frequencies, and duration of use for these medications.
Since 1991, the criteria have been updated twice (in 1997 and 2002) to include ambulatory elderly. The 2002 Beers list included 48 inappropriate drugs or medication classes, regardless of diagnosis or conditions.11 Because drug-disease interactions in the elderly are increasingly recognized, the 2003 Beers list also included inappropriate medications or medication classes for 20 medical conditions. The consensus panel of experts identified 66 inappropriate drugs with adverse outcomes of potentially high severity. The authors stated specifically that the criteria were not meant to regulate practice to the point at which they would supersede the clinical judgment and assessment of the medical practitioner.
Based on Beers’ criteria for inappropriate prescribing, a literature review of studies conducted between 1992 and 1999 found that between 14% and 23% of the elderly filled a prescription for one or more drugs on the Beers list.12 Long-acting benzodiazepines, dipyridamole, propoxyphene, and amitriptyline were among the most frequently prescribed inappropriate medications.
Cardiovascular and psychotropic drugs are most commonly involved in drug-drug interactions. The most common adverse effects are acute renal failure, hypotension, and neuropsychological presentations such as delirium. Risk factors predisposing to adverse reactions are using multiple medications, receiving care from several prescribing clinicians, and filling prescriptions at more than one pharmacy. Physicians should also be vigilant for drug-herbal interactions.
Another phenomenon responsible for adverse drug events is a drug-disease interaction. For example, renal failure or hepatic insufficiency can interfere with detoxification and excretion; ascites can alter the volume of distribution of hydrophilic drugs, while obesity has an altering effect on lipophilic drugs. Patients with advanced cognitive impairment may have increased sensitivity or paradoxical reactions to drugs with central nervous system or anticholinergic activities.
As with safety, effective drug therapy for older people is also far from optimal. Optimal drug prescribing should aim for a balance between overprescribing and underprescribing while keeping a safe environment in mind (i.e., monitoring for adverse drug reactions and reducing medication errors). More than 50% of outpatient prescriptions are without indication, while necessary drugs are withheld in the cases of about 55% of elderly outpatients and 25% of hospitalized elderly patients.13
Overprescribing refers not only to the use of multiple medications but also implies a lack of appropriateness in selection, dosing, or use of the medication. For example, the term “prescribing cascade” refers to adding a new medication to treat symptoms of an adverse drug event that is mistakenly assumed to be a separate new diagnosis. Potential consequences of overprescribing include adverse drug events, drug-drug interactions, decreased quality of life, and unnecessary costs. Common factors connected to overprescribing include, but are not limited to, advanced age, multiple comorbidities, multiple prescribers, poor record-keeping, and failure for healthcare providers to thoroughly review a patient’s medication regimen.
Underprescribing of medications to older people is also of concern. Underprescribing results from efforts to avoid complex medication regimens, fear for adverse events, problems with patient adherence to medications, and economic barriers. Underprescribing can result from the notion that older folks will not benefit from medications intended for primary or secondary prevention or for aggressive management of chronic conditions (e.g., angiotensin-converting enzyme inhibitors and beta blockers prescribed for congestive heart failure and after a myocardial infarction).
New Prescribing Initiatives
There have been new initiatives to emphasize optimal prescribing. The Joint Commission on Accreditation of Healthcare Organizations (JCAHO) mandates medication reconciliation across inpatient and outpatient practices. In 1999, the Centers for Medicare and Medicaid Services (CMS) expanded the drug use review policy for nursing home certification. Using specific criteria, surveyors and pharmacists must assess resident records for potentially inappropriate medication exposures and associated adverse drug reactions. The “Assessing Care for Vulnerable Elders” (ACOVE) initiative implemented use of quality indicators for prescribing appropriate medications, documentation, education, and medication monitoring. The White House Conference on Aging, held in December 2005, also addressed medication management issues in its resolution entitled “Optimize Medication Management Programs.”
There are a few principles for prescribing that the clinician can keep in mind while caring for the older person. When starting therapy, the basic principle should be to start low and go slow. New complaints or worsening of an existing condition after a drug has been introduced should be scrutinized for the possibility of a drug-induced problem. When choosing treatment for a new medical condition, always consider non-pharmacologic approaches first.
Overprescribing can also be prevented by regularly reviewing a patient’s medication list each time a new medication is started or changed. It is important to know what other providers have prescribed and where prescriptions were filled. It is essential to maintain accurate records. In this regard, the use of electronic medical records can be both an advantage and a disadvantage. Inaccurate drug lists can be self-perpetuating when providers simply copy and paste these sections of the medical records. It is best if the patient can bring all medications, including those purchased over the counter, to the visit. Discontinue any medications that are deemed to be unnecessary after review.
A Few Final Suggestions
For many reasons, patient compliance and adherence can be problematic in older patients.14 Patients often don’t admit not taking their medications as directed. If nonadherence is suspected, the care provider should consider the patient’s financial, cognitive, and functional status, as well as the patient’s beliefs about and understanding of the medications and disease. A simple regimen (such as once daily dosing) and a caregiver who is involved in overseeing medication management are helpful. Medication trays or drug calendars are handy tools. Many older folks may need the reassurance regarding safety that additional education or reinforcement can provide.
Regardless of the steps the physician takes to ensure safe prescribing for the elderly, provider-patient communication is of utmost importance. TH
Dr. Egger works in General Internal Medicine, Section Hospital Medicine, at the Mayo Clinic in Rochester, Minn.
- Winterstein AG, Sauer BC, Hepler CD, et al. Preventable drug-related hospital admissions. Ann Pharmacother. 2002;36(7-8):1238-1248.
- Kohn L, Corrigan J, Donaldson M, eds. To Err Is Human: Building a Safer Health System. Committee on Quality of Health Care in America, Institute of Medicine. Washington, D.C.: National Academies Press; 2000.
- Bond CA, Raehl CL, Franke T. Medication errors in United States hospitals. Pharmacotherapy. 2001 Sep;21(9):1023-1036.
- Goulding MR. Inappropriate medication prescribing for elderly ambulatory care patients. Arch Intern Med. 2004 Feb;164(3):305-312.
- Zhan C, Sangl J, Bierman AS, et al. Potentially inappropriate medication use in the community-dwelling elderly: findings from the 1996 Medical Expenditure Panel Survey. JAMA. 2001 Dec 12;286(22):2823-2829.
- Cooper JW. Probable adverse drug reactions in a rural geriatric nursing home population: a four-year study. J Am Geriatr Soc. 1996 Feb;44(2):194-197.
- Hanlon JT, Artz MB, Pieper CF, et al. Inappropriate medication use among frail elderly inpatients. Ann Pharmacother. 2004 Jan;38(1):9-14.
- Beard K. Adverse reactions as a cause of hospital admission in the aged. Drugs Aging. 1992 Jul-Aug;2(4):356-367.
- Lazarou J, Pomeranz BH, Corey PN. Incidence of adverse drug reactions in hospitalized patients: a meta-analysis of prospective studies. JAMA. 1998 Apr 15;279(15):1200-1205.
- Beers MH, Ouslander JG, Rollingher I, et al. Explicit criteria for determining inappropriate medication use in nursing home residents. UCLA Division of Geriatric Medicine. Arch Intern Med. 1991 Sep;151(9):1825-1832.
- Fick DM, Cooper JW, Wade WE, et al. Updating the Beers criteria for potentially inappropriate medication use in older adults: results of a US consensus panel of experts. Arch Intern Med. 2003 Dec 8-22;163(22):2716-2724.
- Aparasu RR, Mort JR. Inappropriate prescribing for the elderly: beers criteria-based review. Ann Pharmacother. 2000 Mar;34(3):338-346.
- Hanlon JT, Schmader KE, Ruby CM, et al. Suboptimal prescribing in older inpatients and outpatients. J Am Geriatr Soc. 2001 Feb;49(2):200-209.
- Moisan J, Gaudet M, Gregoire JP, et al. Non-compliance with drug treatment and reading difficulties with regard to prescription labelling among seniors. Gerontology. 2002 Jan-Feb;48(1):44-51.