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Prescription and Over-the-Counter Drug Misuse
Among the
Elderly
by David W. Oslin,
M.D.
Geriatric Times May/June 2000 Vol. I Issue 1
It is well-documented
that older adult patients are the largest consumers of prescription
medications. Recent estimates show that adults age 60 and older take
an average of five prescription medications each day (Golden et al.,
1999). In 1997, Stoehr and colleagues found that 87% of older
individuals (mean age 74.5 years) reported regular use of at least
one over-the-counter (OTC) medication, and 5.7% were taking five or
more OTC medications daily. Given the recent rise in use of
nutriceuticals such as herbal remedies, these figures are likely to
be underestimates. There has been consistent concern that the number
of medications taken by older adult patients can lead to an excess
in disability and the potential for life-threatening illness. This
concern was highlighted in a recent U.S. General Accounting Office
report on adverse drug events (2000). Furthermore, it is important
to consider specifically the effects of central nervous system
active medications because they are commonly used by older adults
and because the brain is the most vulnerable of human systems.
What lies behind the use of a large number of medications? Does this
polypharmacy represent medication mismanagement, or is it merely
reflective of the increased number of illnesses present later in
life? Perhaps the quantity of medications is reflective of medical
science's advances, which have produced medications with greater
specificity and more combination treatment.
Despite the growing number of available medications, however, it is
likely there is significant misuse, such as using medications with
non demonstrated efficacy for the patient's symptoms or illness,
using medications with excessive risks among the elderly and
continuing medications without specified benefit.
Indeed, a 1999 study of older primary care patients by Straand and
Rokstad estimated that 13.5% of all prescriptions given during a
two-month period were inappropriate, based upon excessive dosing,
potentially harmful drug combinations or the use of contraindicated
medications for an older adult population.
Also well-documented are concerns about the use of multiple
medications and the possible exposure to a greater number of adverse
events, increased financial costs, drug interactions (leading to
unique adverse effects or a change in an agent's efficacy), and
increased errors in taking the medications on a proper schedule.
Thus, the solution seems simple. Clinicians should be fastidious
about the purpose of each medicine used (both prescription and OTC),
as well as the withdrawal of medications with
no demonstrated effect. Moreover, they should avoid certain
medication and drug combinations that are especially hazardous in
older adults. This task is complicated because health care for the
elderly tends to be fragmented among several providers, and each
clinician has less time to see patients or to monitor all aspects of
a patient's health care.
Each treatment we prescribe or recommend has certain risks and
benefits. Properly weighed, this ratio should favor a benefit.
Having said this, certain medications are associated with greater
risk than others. For instance, benzodiazepines can increase the
risk of falls and thus fractures (Gales and Menard, 1995; Herings et
al., 1995), cause impairment to driving skills (Hemmelgarn et al.,
1997), disrupt sleep cycles (Newman et al., 1997) and, among the
frail elderly, cause excessive disability
(Ried et al., 1998).
Similarly, diphenhydramine (Benadryl) has been shown to produce
cognitive deficits in healthy elderly patients, raising the
possibility of excessive cognitive deficits in patients with
dementing illnesses (Katz et al., 1998; Morrison and Katz, 1989).
Risk exposure is heightened when the medication is used for a longer
duration than intended or warranted, or when the medication is
improperly prescribed (e.g., giving an excessive dose or prescribing
the medication for the wrong indication). Examples among the elderly
include: prolonged use of sedative medications such as
benzodiazepines or diphenhydramine for insomnia; use of anti-anxiety
medications for the treatment of depression or chronic pain; and the
use of high doses of antipsychotics for the treatment of behavioral
disturbances associated with dementia.
One approach to reducing the number of inappropriate medications is
to develop medication-specific policies that either limit access to
use or trigger inquires about use. Conceptually, a threshold can be
set for both dose and duration of exposure allowing detection of
patients taking high doses of a medication and those on medications
longer than would be reasonable clinical practice. In HMOs, this
type of tracking easily could be implemented using prescription
claims.
As another example, a multisite collaborative project, funded by the
Substance Abuse and Mental Health Services Administration and the
U.S. Department of Veterans Affairs, recommended targeting patterns
of near daily use of benzodiazepines or opioids for more than three
months. As part of this study, patients enrolled in primary care
were asked about their medication use. Those who were above the
threshold for use were referred for an evaluation of the
prescription's medical necessity. Following passage of the Omnibus
Budget Reconciliation Act of 1987, this approach was adopted in
nursing home regulations that require justification of use of a
variety of medications, including benzodiazepines and antipsychotics,
that exceed certain dose limits.
Using treatment guidelines for various disorders is another approach
to improved medication use. This methodology has been used in
various disease management programs and in guideline-driven care for
disorders such as depression, diabetes, hypertension and congestive
heart failure. The purpose of providing guideline-adherent or
algorithm-based care is to increase the precision of prescribing,
document response and eliminate drugs that do not demonstrate the
desired effect. (The American Psychiatric Association has 10
guidelines for psychiatric disorders posted on its Web site
www.psych.org in the clinical resources section. Other
guidelines are available at the National Guideline Clearinghouse
www.guideline.gov-Ed.) Computer-assisted programs are being
developed that trigger reminders to conduct assessmeents at specific
points in the treatment. The assessments are fed back into the
computer to determine response over time. The clinician then can be
provided with treatment suggestions.
In summary, many older adults suffer from multiple medical problems,
each warranting treatment. In many instances, this leads to an
appropriate degree of polypharmacy. It is incumbent upon us as
clinicians, however, to be ever careful about the rationale for
using each medication and to have clear goals when starting new
medications. These goals should always include target responses and
contingencies for discontinuing medications that cause excessive
adverse effects or do not demonstrate the desired response. The use
of algorithms, computer-assisted programs and other tools should be
embraced, not feared, by clinicians, as these will ultimately lead
to better care for our patients.
Dr. Oslin is assistant professor in
addiction and geriatric psychiatry in the department of geriatric
psychiatry at the University of Pennsylvania
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