By Stanley Hartgraves, PhD, PT; Pam Kasyan-Itzkowitz, MS, OTR/L; and Martha Tristan-Hartgraves, PhD, OTR/L
Drugs, therapy, rehabilitation outcomes…What is the role of the therapist in recognizing the impact of drugs on the treatment program or perhaps in recommending alternatives? How prepared are therapists in performing this role?
The typical therapist has limited formal exposure to the topic of pharmacology. In most academic programs for therapists, pharmacology is not considered a basic subject essential to the preparation of the competent practitioner. Pharmacology definitely receives much less emphasis compared to subjects such as anatomy, neuroscience, pathology, and physiology. However, most therapists recognize the importance of understanding the effects of drugs once they begin practicing, as evidenced by their attendance at presentations on rehabilitation pharmacology at professional conferences.
We believe that the subject of pharmacology warrants more time (in both lecture and case study formats) in professional educational programs. As professions push for more autonomy of practice, stronger knowledge of basic pharmacology, drug interactions, and side effects becomes even more important.
So what are the advantages of knowing more about this topic in the clinical setting? The knowledge of how certain medications may interact with rehabilitation procedures is helpful in getting the optimal response from the patient to both drugs and therapy. For instance, scheduling a patient for therapy when certain drugs reach their peak effect may improve the therapy session dramatically. Conversely, some sessions that require the patient’s full participation may be useless if medications cause sedation or produce balance deficits.
Specific concerns with geriatric patients include too much drug usage (polypharmacy), inappropriate use, and altered response to an appropriate drug (perhaps due to changes in kidney or liver function). An example of the latter is well illustrated by the difference in half-life (time for half of the administered dose to be absorbed by the body) in the older patient versus the young. For the commonly prescribed drug diazepam, the approximate half-life in the younger patient is 20 hours, whereas it can be up to 90 hours in the elderly. Awareness of this difference will, at the minimum, alert the therapist to a possible reason for the lack of motivation/attention of the patient to the therapy session. More proactive therapists could bring their observations to the medical staff and perhaps effect a change in medication or at least a reduction in dosage.
THE EFFECT OF DRUGS ON OUTCOMES
Some of the best research on the impact of drugs on outcomes has been conducted in the area of stroke rehabilitation. Drugs commonly used to manage patients after stroke may actually interfere with rehabilitation and, ultimately, contribute to a slower recovery. Drug groups identified as problematic from animal studies (many of which were conducted in the laboratories of Dennis Feeney, PhD, professor, Department of Psychology and Neurosciences at the University of New Mexico, Albuquerque) include antiseizure drugs, antianxiety drugs, antidepressants, neuroleptics, and antihypertensive drugs.
In a prospective 1990 study, Goldstein et al administered these commonly used drugs to patients with recent strokes, and then followed their rehabilitation outcomes. The patients who received these drugs had slower sensorimotor function, were more dependent in activities of daily living (ADLs), and, generally, had delayed 30-day recoveries.1 In a 1995 retrospective study of a larger group of patients who had ischemic strokes, Goldstein et al found that approximately a third of the patients were given the same categories of drugs during the first few weeks of medical management.2 Measures such as the Toronto Stroke Scale (motor assessment) and the Barthel Index (ADL assessment) indicated that recovery was affected in the subjects receiving the detrimental drugs. This slowing of recovery could be due to delayed resolving of diaschisis (inactivation of bordering/distant neurons secondary to injury) and/or the lack of drive, attention, and motivation secondary to the medications. These studies by Goldstein and Feeney suggest that a variety of drugs might impede progress in stroke rehabilitation and, therefore, should not be used, or should be used with caution in the first few weeks following stroke. In a recently completed study (2002) by physical therapy students at Widener University, Chester, Pa (in partial fulfillment for the MSPT degree, and supervised by one of the authors), it was found that there is continued use of these purportedly detrimental drugs in major medical centers.
Interestingly, there have been studies to identify drugs that might improve outcomes following neurological injury. In 1992, Walker-Batson et al investigated the effect of amphetamine on speech therapy in a stroke population.3 The results were promising, and led to another study investigating motor recovery in patients 30 days poststroke. These patients were administered either amphetamine or a placebo every 4 days for 40 days, while receiving physical therapy.4 Results were promising, as functional outcome (Fugl-Meyer Motor Scale) improved in the group receiving amphetamine, which may have been due to improved attention or to plasticity (neural reorganization).
Pharmacological approaches should not be seen as magic bullets that work without other intervention. Active involvement of the patient and carefully designed and administered physical therapy, occupational therapy, and communicative programs are essential to successful outcomes. Studies in animals have shown that those animals receiving only a stimulant without “therapy” did not show the gains when both were employed.5
EVALUATION TOOLS
There are two useful tools that pharmacologists, physicians, and pharmacists use to evaluate patient medications (especially for the elderly): the Beers List6 and the Medication Appropriateness Index (MAI).7 The Beers List is useful as a screening tool. It is a list of drug categories and specific generic drugs organized according to high and low severity agents as well as common side effects.
The MAI is useful as an evaluation tool. It includes drug appropriateness categories/questions that provide a guide for the health care team to assess each drug that has been prescribed. Some representative questions addressed by the MAI are: 1) Is there a current indication for the use of the drug? 2) Is the dose correct? 3) Are the directions correct and practical? 4) Is there unnecessary duplication? While it is not within the typical therapist’s purview to evaluate the questions posed by the MAI, it does provide areas of concern to discuss with other health care professionals, especially when the functional evaluation suggests that drugs may be impeding patient progress.
CASE STUDY
Rebecca Sleeper, PharmD, assistant professor in the School of Pharmacy at Texas Tech University, Lubbock, has developed a series of case histories based on her experiences and used for educational purposes. We use one of these case histories, modified for this article, to illustrate the analytical process needed to assess the impact of drugs.
Background and drugs: MK is a 77-year-old man and a long-term care resident. He has a history of recent falls and a diagnosis of Alzheimer’s disease. His medications include donepezil (cholinesterase inhibitor), chewable calcium, a chewable multivitamin, and lorazepam (a benzodiazepine, which he takes up to three times a day, as necessary).
The nursing assessment of MK notes recent agitated behavior; however, the physical examination, vital signs, and laboratory studies are within normal limits. Functional status has changed since the last comprehensive examination. MK has balance difficulties and requires more assistance with ADLs. He has been noted to “furniture surf” in getting around his room. MK has also shown a significant decline in cognitive status in the past 30 days. His Mini-Mental Examination score has declined by ~50%.
To determine if this is a possible drug-induced deterioration in cognition and functional independence, we can use the Beers List to see if any of the signs/symptoms are associated with particular classes of drugs. Examining the list of side effects, we see a category for falls and a category for cognitive impairment. Falls can be caused by antipsychotics, antidepressants, and/or benzodiazepines. Cognitive impairments can be caused by anticholinergics and/or benzodiazepines. Donepezil is a cholinergic agonist (not an anticholinergic), and therefore would not logically be associated with MK’s functional and mental changes. It is still possible that the decline in mental status is part of a progression in MK’s Alzheimer’s disease. However, we note that lorazepam is a benzodiazepine and could possibly cause both cognitive changes and balance difficulties. We also note that this drug is being used as necessary, which could be a factor in causing impairments. Based on the issues presented in this case, the most prudent approach would be to eliminate the lorazepam or at least reduce the daily dosage.
Therapists need to know the drugs that their patients are taking, and the general purpose and side effects of those drugs. Access to a handy reference source is mandatory. Therapists need to go beyond merely observing, but should incorporate questions about drug usage into the evaluation and progress reports.
References
Stanley Hartgraves, PhD, PT, is adjunct professor in the Physical Therapy Program, University of New Mexico in Albuquerque. Pam Kasyan-Itzkowitz, MS, OTR/L, is assistant professor, fieldwork coordinator, Occupational Therapy Department at Nova Southeastern University, Fort Lauderdale, Fla. Martha Tristan-Hartgraves, PhD, OTR/L, is assistant professor, Occupational Therapy Program, Department of Orthopedics, at the University of New Mexico, Albuquerque.
