Differences in Pain Medication Use in Stroke Patients With Aphasia and Without Aphasia
Background and Purpose While individuals with stroke are known to experience pain for a variety of reasons including premorbid conditions and stroke-specific sequelae, there are some groups of individuals with stroke, who because of aphasia, are unable to express their pain. This study investigated whether there exists an association between severity of aphasia and overall pain medication use as indicated (1) by the proportion of individuals medicated according to aphasia severity and (2) by the dosage of pain medication used according to aphasia severity.
Methods The study involved a retrospective chart review of 207 charts of patients with stroke admitted to the Jewish Rehabilitation Hospital (JRH), Laval, Canada. Patients were classified into three groups according to level of expressive aphasia: those without aphasia, those with mild-to-moderate aphasia, and those severe aphasia. Information on medications used primarily for pain management was elicited for the first 21 days and the last 5 days of hospitalization. Any substitution, increase, elimination, or addition of pain medication during hospitalization was also monitored.
Results and Conclusions While the findings indicate that pain medication prescriptions were similar for all patients, a significantly smaller number of individuals with aphasia received pro re nata (prn) “as required” pain medication when compared with those without aphasia, for the first 21 days and for the last 5 days of hospitalization at the JRH. Similarly, when daily dose was monitored for the same time periods, individuals with aphasia were found to have received less medication for pain than those without aphasia.
Individuals with stroke experience pain that can impact substantially on their sense of well-being and quality of life. Within the first month poststroke onset, 72% of stroke patients may suffer from what is referred to as the shoulder-hand syndrome1 2 and 18% to 38% from headaches.3 4 5 6 There also exists an 8% incidence of chronic pain “central post-stroke pain.”7 Furthermore, those with stroke, who are generally elderly, often experience pain from chronic conditions such as arthritis and other musculoskeletal conditions. Although most individuals with pain can assist in their own pain management, either by using verbal communication or with the assistance of a standardized pain assessment scale to express the type and degree of pain they are experiencing, there are some groups of individuals with stroke who are unable to express their pain, notably those with impaired communication. This study focused on this group specifically, that is, on individuals with aphasia who are unable, in varying degrees, to comprehend or use verbal communication to express their needs.
In the hospital nurses administer medication for pain, particularly “prn” (pro re nata, “as required”), upon request of the patient or based on their personal judgment of a patient’s needs. Under the hypothesis that those with aphasia may be unable to express their need for medication, the question arises as to whether individuals with aphasia are receiving medication that is similar in frequency and dose to that received by those without aphasia. If those with aphasia experience pain similar to those without, then the two groups should display similar patterns of pain medication use. An extensive search of the literature failed to reveal any information that has addressed this issue.
Thus, the global objective of this study was to compare pain medication use in individuals with and those without aphasia. More specifically, as difficulty to communicate increases with severity of aphasia, we investigated whether there exists an association between severity and overall pain medication use as indicated (1) by the proportion of individuals medicated according to aphasia severity and (2) by the dosage of pain medication used according to aphasia severity. Second, we studied substitution, increase, elimination, and addition in pain medication use during hospitalization according to severity of aphasia.
Subjects and Methods
This study involved a retrospective review of charts of patients with stroke admitted to the Jewish Rehabilitation Hospital (JRH) from January 1988 to June l993. It was deemed necessary to go this far back to a period of time when pain medication use in individuals with aphasia was not already an important focus of the clinical team. The JRH, a McGill-affiliated teaching hospital, is a 120-bed adult physical medicine setting serving Montreal, Quebec, Canada and surrounding regions. The JRH is the largest inpatient stroke rehabilitation center in Quebec. The goal was to accrue three groups of individuals with stroke: those with no aphasia, those with mild-to-moderate expressive aphasia, and those with severe expressive aphasia. Sample size calculations were based on clinical suggestions that pain medication is used by approximately 40% of stroke patients with aphasia and 65% of those without aphasia. Setting a power of .80, an alpha of .05, the proportion of medication use at .40 and .65 in those with and without aphasia, respectively, calculations indicated that a total of 207 individuals were required (69 in each group) to achieve sufficient numbers for the data analyses. The required size for each group was achieved by sampling the charts of stroke patients admitted to the JRH in each of the 5 years.
Inclusion in the study required a primary diagnosis of stroke at the time of admission to the JRH as indicated by the medical summary and CT scan from the acute care hospital and a minimum inpatient rehabilitation stay of 4 weeks. Patients with severe cognitive and/or severe psychological problems, as indicated in the neuropsychology report, were excluded. Those with a previous admission for stroke at the JRH were excluded because it was possible that during a previous stroke admission the nursing staff may have become acquainted with the patient’s pain-related behaviors. This project was approved by the Research Ethics Committee of the Jewish Rehabilitation Hospital.
For each patient, information on basic sociodemographic variables (eg, age, sex, language or languages spoken and understood) was abstracted from the admission records. Information on site of lesion, comorbid conditions, presence of hemiplegia, paresis, and hemineglect was also recorded from the patient’s medical records. Information on the presence of aphasia and its classification in terms of type and severity was obtained for those with aphasia from the records of the treating speech-language pathologist. Standard assessment and documentation procedures were in place in the Speech Pathology Department during the entire study period.
Classification of Aphasia Severity
Patients with aphasia are assessed by the speech-language pathologist, within 72 hours of admission. Assessment is based on standardized tests, including the Boston Diagnostic Aphasia Examination,8 the Western Aphasia Battery9 for English-speaking patients, and the Montreal-Toulouse Aphasia Battery10 for French-speaking patients. Results are summarized in an initial report. This report was reviewed by the collaborating speech-language pathologist and the principle investigator who together reached a determination regarding aphasia classification. Patients without an apparent language deficit were not evaluated by a speech-language pathologist. Verification of the appropriateness of these individuals to be classified as nonimpaired was obtained through a review of the reports of all disciplines.
Ascertainment of Pain Medication Use
Information on medications used for pain management was elicited from the medication records completed on a 24-hour basis by the nurse responsible for medication administration. The information included the medication name, dosage, and time of administration. Before the initiation of this study, meetings were held with a multidisciplinary team to determine medications commonly used to manage pain in this clientele. After much deliberation it was decided that the following medications would be considered as being used only for pain management: acetaminophen without codeine and with codeine, naproxen, indomethacin, and acetylsalicylic (ASA), as these categories accounted for almost 100% of the pain medications used. Other ASA medications, such as Entrophen, that may or may not have been used for pain control, were excluded from the analyses.
Pain medication used for the first 21 days and the final 5 days of hospitalization at the rehabilitation center was recorded. After the first 21 days any pain medication administered for more than 24 hours was also recorded, for a period up to 7 days. In addition, medication prescribed both in the acute care hospital and upon admission to the rehabilitation facility was abstracted from the physician’s prescription orders. Finally, the addition of any new pain medication, the substitution of one pain medication for another, the increase in dosage, or the elimination of a prescribed pain medication were identified by reviewing the daily medication records.
The percentage of individuals for which pain medication prescriptions had been completed in the acute care hospital was calculated according to group (no, mild-to-moderate, severe aphasia). A similar comparison across groups was performed using the prescription orders from the rehabilitation setting. The number of individuals for whom pain medication was both prescribed and used was analyzed according to group using χ2 analyses. Because it was hypothesized that the biggest differences in use between groups would exist early in the hospitalization, preliminary calculations focused on differences in dosage and numbers of individuals receiving pain medication during the first 7 days. Further analyses explored these variables in the first 21 days and again in the final 5 days of rehabilitation hospital stay. Finally, the total number of substitutions, dose increases, eliminations, or additions of pain medication according to group were calculated.
The characteristics of the group under study by severity of expressive aphasia at admission are shown in Table 1⇓.
The three groups were similar with respect to sex, age, and total number of comorbid conditions. As anticipated, the majority of the patients with aphasia had experienced a left-hemisphere stroke, whereas those without aphasia had experienced a right-hemisphere stroke. The length of stay for the two groups with aphasia was longer than for those without aphasia.
Table 2⇓ describes the number of individuals in each group for whom pain medication prescriptions had been completed in the acute care hospital. Across the three groups, χ2 analyses comparing the proportions of individuals in each group that received prn prescriptions for pain relief revealed no significant differences (χ2=1.18; P=.55, df=2). Similarly, when comparisons were made in prn pain medication upon admission to the rehabilitation hospital, there were no differences in the percentages of individuals for whom pain medications were ordered across the three groups (χ2=1.43; P=.49, df=2). When the number of individuals for whom acetaminophen was prescribed and used across the three groups in the first 21 days of rehabilitation hospitalization, a significant difference was found in the proportions of those prescribed and those who actually used acetaminophen across the three groups; the greatest proportion of use was in those without aphasia (88%), followed by those with aphasia mild-to-moderate (51%) and severe (55%) aphasia (χ2=10.79; P<.01, df=2). Only 4 of 34 people without aphasia for whom acetaminophen had been prescribed did not receive any during the first 21 days of hospitalization, while 15 of 33 individuals with severe aphasia did not receive any. In the last 5 days of rehabilitation hospitalization a trend was found that was similar to that of the earlier period of hospitalization, with the highest proportion of use in those without aphasia (56%), as compared with those with mild-to-moderate and those with severe aphasia, 29% and 27%, respectively (χ2=7.13; P<.05, df=2).
Fig 1⇓ details the number of individuals who received acetaminophen in the first 21 days of hospitalization according to severity of aphasia. Overall there were consistently more individuals without aphasia receiving acetaminophen. This difference between groups was most pronounced in the first few days of rehabilitation hospitalization. For example, on day 4, 4 individuals with severe aphasia and 5 with mild-to-moderate aphasia received acetaminophen as compared with 13 individuals without aphasia.
When the total daily dosage was compared over the first 21 days of hospitalization (Fig 2⇓), the group of those with severe aphasia received less acetaminophen on each of the days when compared with the group without aphasia. The dosage received by the group with mild-to-moderate aphasia was almost always lower than that received by the group without aphasia, and at times even lower than the dosage received by the group with severe aphasia. When the three groups were compared in terms of the number of individuals with a substitution, addition, increase, or elimination in pain medications during the entire hospital stay, no significant differences were found for these four variables.
This study compared pain medication use in those with intact communication and those with communication deficits after a stroke. Individuals with stroke often experience pain related to conditions such as arthritis, in addition to stroke-specific sequelae such as shoulder-hand syndrome1 2 and poststroke headache.3 4 5 6 Thus, it was anticipated that the need for pain medication among the entire study group would be high. Given that the main interest was in identifying whether stroke patients with aphasia could communicate their need for pain medication, we concentrated on prn analgesic medications that are commonly administered upon request of the client.
The findings of this study indicate that individuals with aphasia are receiving medication for pain that differs in frequency and quantity from that received by patients without aphasia. The Jewish Rehabilitation Hospital has an interdisciplinary team extensively trained in the treatment of stroke and annually admits a large number of individuals with stroke to its stroke unit. Thus, it is likely that the findings of differential pain medication use witnessed in this hospital would also be found in other similar settings.
A potential limitation of this study concerns the classification of the three groups according to level of aphasia. While it is highly unlikely, in a rehabilitation center where each individual is seen by numerous health professionals, that an individual with aphasia would have been classified as nonaphasic, it is possible, that within the group of those with aphasia there was some misclassification. This may in part explain why no large differences were seen in the dosage and frequency of prn pain medication use between the mild-to-moderate and severe groups, while statistically significant differences were found between those with and those without aphasia.
One of the unanswered questions of this study is whether those with aphasia suffered from less pain than that experienced by those without aphasia. If the answer to this question is yes, then it might explain why this group received less pain medication. However, if as a group they had pain experience similar to those without aphasia, then the plausible explanation is that the presence of aphasia limited their ability to request pain medication. The finding that the number of comorbidities was similar across the groups lends some support for the latter supposition. Those with aphasia did remain in the hospital longer than those without aphasia, which may imply that they were a “sicker” group. Yet, if this group had been sicker, they would potentially have needed more pain medication, not less.
This study has raised concern that individuals with aphasia may not be receiving proper management for pain because of our failure to correctly identify and assess their needs. On the basis of these findings, a second phase of this research has already been launched to assess the use of various nonverbal assessment scales to elicit information on pain severity from those with aphasia.
This study was supported by a grant from the Reseau de recherche en réadaptation de Montréal et de l’ouest du Québec (RRRMOQ) and was carried out under the continuous support of the JRH Foundation. We gratefully acknowledge the work of S. Rosenmeier, J. Tarasuk, P. Romiti, J. Bitensky, and L. Mestel at different stages of this study.
- Received March 24, 1997.
- Revision received June 18, 1997.
- Accepted June 18, 1997.
- Copyright © 1997 by American Heart Association
Kumral E, Bogusslavsky J, Van Melle, G Regli, F Pierre P. Headache at stroke onset: the Lauzanne Stroke Registry. J Neurol Neurosurg Psychiatry. 1995;58:490-492.
Jorgensen HS, Jerpersen HF, Nakayama H, Raaschou HO, Olset TS. Headache in stroke: The Copenhagen Stroke Study. Neurol. 1994;44:1793-1797.
Arboix A, Massons J, Oliveres M, Arribas MP, Titus F. Headache in acute cerebrovascular disease: a prospective clinical study in 240 patients. Cephalal. 1994;14:37-40.
Goodglass H, Kaplan E. The Assessment of Aphasia and Related Disorders. 2nd ed. Philadelphia, Pa: Lea & Febiger; 1983.
Kertesz A. Western Aphasia Battery. New York, NY: Academic Press; 1982.
Nespoulous JL, Lecours AR, Lafond D, Lemay A, Puel M, Joanette Y, Cot F, Rascol A. Montreal-Toulouse ‘M1-BETA’ Aphasia Battery; 1986.