| | Cognitively Impaired Stroke Patients Do Benefit From Admission to an Acute Rehabilitation UnitAbstract Rabadi MH, Rabadi FM, Edelstein L, Peterson M. Cognitively impaired stroke patients do benefit from admission to an acute rehabilitation unit. ObjectiveTo determine whether cognitively impaired stroke patients benefit (defined as having an improved level of functional independence and capable of being discharged home) from admission to an acute rehabilitation unit. DesignRetrospective analysis of data from a historical cohort of patients with acute stroke within the last 4 weeks or less. SettingAcute stroke rehabilitation unit. ParticipantsThe study sample was divided into 4 distinct groups based on admission Mini-Mental State Examination (MMSE) scores: cognitively intact (MMSE score range, ≥25 points), mild cognitive impairment (MMSE score range, 21–24), moderate cognitive impairment (MMSE score range, 10–20), and severe cognitive impairment (MMSE score range, ≤9 points). InterventionsNot applicable. Main Outcome MeasuresPrimary outcome measures were: change in total FIM instrument score, cognitive FIM subscore, length of stay (LOS), FIM efficiency, and discharge disposition (home vs not-to-home). ResultsBased on the MMSE cut scores, there were 233 cognitively intact patients and 435 cognitively impaired (mild, n=139; moderate, n=165; severe, n=131) patients. The cognitively intact and the 3 cognitively impaired groups were similar in age, sex, and ethnicity. The data show that the 3 cognitively impaired groups of patients had delayed onset to acute rehabilitation admission and greater stroke severity and disability. The change in FIM total score and FIM efficiency was similar between the cognitively intact and the 3 cognitively impaired groups (P=.058). There were, however, statistically significant changes in the FIM cognitive subscore favoring the cognitively impaired groups (P<.001). Similarly, patients in the cognitively intact group had a shorter LOS (P<.001) and more home discharges (P<.001). ConclusionsOur results suggest that despite severe neurologic impairment(s) and disability, cognitively impaired stroke patients make significant functional gains while undergoing rehabilitation and many can be discharged home. Based on these results, stroke patients with cognitive impairments benefit from rehabilitation and should be given the same access to acute rehabilitation services as stroke patients who are cognitively intact. COGNITIVE IMPAIRMENT OCCURS in 5% to 10% of the elderly population,1, 2 and in 12% to 56% of patients poststroke.3, 4 The growing elderly population has an increased risk for stroke and therefore is at an increased risk for cognitive impairment. Patients with cognitive impairment, which is a common consequence of stroke, are often restricted from, and even denied, access to rehabilitation services because they are considered less likely than cognitively intact patients to benefit from such services.5, 6, 7 Several studies have shown the impact of a stroke on cognition. In the Framingham Study,8 74 patients who had a stroke during a 13-year period were compared with 74 control subjects matched for age and sex. The study found that the stroke patients had a significantly lower mean Mini-Mental State Examination (MMSE) score ± standard error at prestroke baseline (27.28±0.34) compared with the control subjects (28.08±0.21). This difference was more pronounced after the stroke (23.57±0.92 vs 28.31±0.25, P<.001). Computed tomography (CT) head scans showed that this poststroke decline in cognitive function correlated with large, left-sided stroke. According to the Center for Epidemiologic Studies Depression scale, depressive symptoms were more frequent in these stroke patients than in the control subjects; the study also found that intellectual decline was independent of the presence of depression.8 Similarly Pohjasvaara et al,9 in the Helsinki Stroke Aging Memory Study of 486 consecutively admitted ischemic stroke patients aged 55 to 85 years, found cognitive decline in 61.7% of the patients, based on their MMSE scores. In the groups aged 55 to 64, 65 to 74, and 75 to 85 years, the frequency of any cognitive decline was 45.7%, 53.8%, and 74.1% (P<.001), respectively. Thus, these studies documented that cognitive impairment is a common consequence of stroke and is the most common mental impairment associated with ischemic lesions in comparison with depression, anxiety, and psychosis. The relation between cognitive impairment and depression after stroke is a complex one, often additionally affected by lesion location. Bolla-Wilson et al10 found that stroke patients with left-hemisphere lesions and depression performed significantly below nondepressed patients on 4 of 9 cognitive domains on a neuropsychologic test battery. Stroke patients with right-hemisphere lesions and depression, however, did not perform below nondepressed patients on any of the 9 domains. This differential effect of depression on cognitive performance between left- and right-hemisphere lesion groups could not be accounted for by demographic variables, neurologic symptoms, or lesion size. A longitudinal study of 103 patients with ischemic left cerebral hemisphere lesions found that cognitively impaired patients with depression had smaller lesion volumes on head CT compared with nondepressed, cognitively impaired patients. At 6 months, nondepressed patients had significant improvement of their cognitive impairment and depressed patients showed no improvement. Bolla-Wilson et al10 concluded that the degree of cognitive impairment was dependent on both depression and lesion volume. Recently, Spalletta et al,11 in a univariate analysis of variance, showed that MMSE scores ± standard deviation (SD) differed for depressed patients with left- versus right-sided stroke (12.3±9.0 vs 23.7±7.1, P<.001). Similarly MMSE scores were significantly lower in left-sided lesions in patients with major depression than the scores of those with minor depression or no depression (12.3±9.0 vs 18.9±8.5, P<.001). After a series of stepwise multiple regression analyses, Spalletta showed depression severity was a predictor of cognitive level in left-hemispheric stroke patients only. Fortunately, successful treatment of poststroke depression does improve cognitive function as measured by standard tests.12 Thus, the presence of concomitant depression with left-hemisphere damage makes cognitive impairment worse. Finally, this association between depression and cognitive impairment is most evident during the first year after stroke and is the strongest in the acute poststroke period.13 It has been hypothesized that both cognitive impairment and depression may be the result of a serotonergic dysfunction induced by left-hemisphere injury. The impact of cognitive impairment on functional outcomes has been extensively studied in elderly patients admitted to a geriatric rehabilitation unit14, 15, 16 and in stroke patients in community settings.17, 18, 19, 20, 21 All of these studies found significant improvement in functional outcomes in patients with cognitive impairment. The initial acute rehabilitation period has been identified as a period when maximum poststroke functional recovery occurs.22 The impact of cognitive impairment on functional outcomes during this period has not been reported. Stern et al23 evaluated predictors of stroke outcome in an acute rehabilitation setting and found that 62 stroke patients with severe motor weakness (hemiplegia) and hemisensory loss had poor functional outcomes, as measured by the Kenny Institute of Rehabilitation Self-care Evaluation Procedure. Similarly, in a prospective evaluation of 536 stroke patients admitted to a rehabilitation unit, Ween et al24 found that age (<55y), higher admission FIM scores (>80), lacunar strokes, right-hemisphere lesions, and a dedicated caregiver at home all facilitated discharge to home. Fong et al25 studied the relationships between motor and cognitive abilities and functional performance in 37 patients with first stroke admitted to a rehabilitation hospital and found that motor impairment, including balance and lower-limb ability, strongly correlated with functional recovery. Thus, in these functional outcome and discharge disposition studies in acute stroke rehabilitation settings, only physical impairments and disability have been prognostic factors. Discharge disposition is a valid measure with which to evaluate the effectiveness of rehabilitation strategies in achieving independence and reintegration into the community. Factors known to influence home discharge include: age, prior functional status, length of stay (LOS), and the social (family and community) support the patient had before the stroke.26 Only 1 study27 has examined the influence of cognitive impairment on home discharge disposition. Thus, the effects of physical impairments after stroke have been frequently studied in stroke outcome and in the care of stroke patients. We therefore decided to study whether cognitively impaired stroke patients could similarly benefit from admission to an acute rehabilitation unit. In our study, “benefit” was defined as an improved level of functional independence (based on FIM instrument total score) and capable of being discharged home. Methods  Participants Six hundred sixty-eight patients consecutively admitted to a designated acute stroke rehabilitation unit over a 24-month interval were studied retrospectively. Inclusion criteria were: recent ischemic or hemorrhagic stroke (≤4wk) confirmed by neuroimaging (CT and/or magnetic resonance imaging). The exclusion criteria were: brain tumor and sudden onset of clinical signs and symptoms due to a brain lesion without a vascular cause. The patients were screened for depression by using the criteria in Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, or by a patient showing behavioral features of depression such as denying being depressed yet refusing to participate in his/her daily rehabilitation therapies. No depressed patient was excluded from the study. The admitting physicians and the rehabilitation team members, who were unaware of the study’s hypothesis, recorded patient demographics, stroke type, site, risk factors, assessment of stroke severity, and functional outcome data in a computerized stroke database. Procedure The admitting physician administered the admission MMSE as a part of the neurologic examination. The MMSE is a standardized, widely used, easy to administer, reliable,28 and a valid29 screening tool used to measure cognitive function, to help quantify the severity of cognitive impairment, and to document cognitive changes occurring over time.30 It has also been widely used in both multicenter research studies and in clinical practice31 as a brief screening instrument for dementia, either alone or as a component of such examination protocols as the Consortium to Establish a Registry for Alzheimer’s Disease battery. The MMSE cannot by itself be used as a diagnostic tool to identify dementia.29, 32 The MMSE evaluates 5 distinct but related domains: concentration or working memory (serial sevens and spelling “world” backward); language and praxis (naming, following 3 commands, construction); orientation (time, place); memory (delayed recall of 3 items); and attention span (immediate recall of 3 items). The construct validity of the MMSE as a measure of cognitive mental state among community-dwelling older adults is well supported.32 It has a total score of 30 with a cut score of 25, above which the person is considered to be cognitively intact. The MMSE has good specificity but limited sensitivity (.96 and .63, respectively) when the conventional cutoff of 24 is applied.33 Kukull et al33 have recommended raising the MMSE cutoff to 26 or 27 to increase its sensitivity in cognitively impaired patients. The main limitations of the MMSE are that it is influenced by age, education, language, and cultural background, but not sex. Ethnicity does affect MMSE performance. For example, African Americans and Hispanics are more likely than European Americans to be erroneously identified as cognitively impaired or demented.34, 35 MMSE scores decrease with age and increase with education. This has been responsible for both floor (difficulty) and ceiling (easy) effect. The change in MMSE scores is not linear when using item response theory methods because of these ceiling and floor effects.36 Though MMSE has been found to be most effective in distinguishing patients with moderate or severe deficits from control subjects,30 it has been less effective in differentiating mildly affected patients from healthy subjects.37 Similarly, MMSE has been less effective in identifying cognitively impaired medical patients32; or identifying patients with focal or lateralized lesions.38 It has also been reported to be insensitive to cognitive impairments resulting from right-hemisphere dysfunction and milder forms of cognitive dysfunction of cortical origin.39, 40 Despite these limitations, the MMSE is a widely used tool to screen and assess cognitive impairment,41 and also has been used to predict important functional outcomes such as medication adherence in cognitively impaired patients,42 hospital and rehabilitation LOS, rehabilitation course and outcome, and risk of death.29, 43 We used admission MMSE scores to divide our study population into 4 groups: severe cognitive impairment (≤9 points), moderate cognitive impairment (10–20 points), mild cognitive impairment (21–24 points), and cognitively intact (≥25 points).44 Outcome Measures The dependent variables were: change in the FIM total score, change in cognitive FIM subscore, LOS, FIM efficiency (change in the FIM total score/LOS), and discharge disposition (home vs not-to-home). We used the FIM instrument to measure both the degree of disability and the progress patients made throughout their medical rehabilitation programs.45 The FIM instrument is a reliable46 and valid47 functional assessment measure widely used in rehabilitation settings.48 The FIM has 18 items and each item is scored on an ordinal scale ranging from 1 to 7. A FIM item score of 7 is categorized as “complete independence,” while a score of 1 is “total assist” (patient performs <25% of task). The possible total score, indicating the level of independence, ranges from 18 (lowest) to 126 (highest). The FIM has a cognitive subscale (5 items), and a motor subscale (13 items), resulting in a cognitive FIM score (range, 5–35) and a motor FIM score (range, 13–91). The FIM cognitive subscore is based on observations of patient behaviors and is, therefore, less affected by aphasia than the MMSE. Stroke rehabilitation team members trained and certified in the use of the FIM scored the admission and discharge FIM total, FIM cognitive, and FIM activities of daily living (ADL) subscores. FIM efficiency was used to measure patient’s rehabilitation progress. An accepted measure of adequate rehabilitation progress is 1 FIM point gain per day.49 All patients, including those with depression, admitted to our rehabilitation unit received a minimum of 3 hours of standard occupational, physical, and speech-language therapies daily. Therapies were tailored to each patient’s needs. We did not consider the effect of intensity of specific therapies for the components of cognitive impairment, that is, language, memory, or neglect. Data Analysis All variables of the prospectively collected data were retrospective analyzed. The statistical analysis compared cognitive impairment—the independent variable—to all of the dependent variables: change in the FIM total score, change in cognitive FIM subscore, LOS, FIM efficiency, and discharge disposition (home vs not-to-home). The differences of continuous, ordinal, and nominal variables between groups were analyzed by analysis of variance (ANOVA) with post hoc Bonferroni-adjusted comparisons, t tests, Mann-Whitney U tests, and chi-square tests, as appropriate. The analysis of covariance was used to include covariates shown to have statistically significant association with the continuous dependent variable in previous tests. We used stepwise linear regression with change in FIM total score as the dependent variable to assess the competing statistically significant associations of admission values on the final change in FIM total score. We used forward stepwise multiple logistic regression to assess the competing strengths of demographic variables that were found associated with change in function or home discharge at an α level of .05 or less. Several models were tested and the best fit is reported here. The effect sizes of the significant findings in functional outcome measures were analyzed using 1-way ANOVA with Bonferroni-adjusted post hoc comparisons. We used a significance level of P less than .05 for all analyses. Except in multivariate analyses, there was no adjustment for multiple comparisons. Statistical analyses were performed using SPSS.a Results In our sample of 668 patients, there were 233 cognitively intact patients (34.88%) and 435 cognitively impaired (65.12%) patients, as determined by the admission MMSE cut score (table 1). The mean age of the study sample ± SD was 70.30±12.61 years (range, 22–96y). The male/female ratio was 311/357. The average time from stroke onset to admission was 11.95±5.90 days. The mean admission FIM total and FIM cognitive scores were 60.14±19.16 and 22.41±6.01, respectively. The 4 groups were similar in age, sex, and ethnicity. Patients with cognitive impairment following stroke, however, were admitted later to our facility than cognitively intact patients (P<.001). Depression, as defined in this study, was present in 29.04% of the study population, with 23.17% of the cognitively intact patients having it and 40.45% of patients with severe cognitive impairment (P=.006) having it. Of all the stroke risk factors, atrial fibrillation was more prevalent in patients with moderate (21.21%) and severe (26.71%) cognitive impairment (P=.004). There were more current smokers in the cognitively impaired group of patients (P=.008). | | |  | Variable | Normal (n=233) | Mild (n=139) | Moderate (n=165) | Severe (n=131) | P | |
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| Patient characteristics | | | | | | | |  Age (y) | 69.14±13.04 | 69.58±13.29 | 71.32±12.04 | 71.73±11.66 | .160 | | | Sex (men/women)⁎ | 114/119 | 69/70 | 69/96 | 59/72 | .445 | | | Ethnicity (W/B/H/A)⁎ | 185/37/8/3 | 103/24/7/5 | 116/36/9/4 | 99/17/14/1 | .060 | | | Onset of stroke to admission (d) | 10.84±5.55 | 11.26±5.56 | 12.65±5.88 | 13.75±6.31 | <.001 | | | Risk factors⁎ | | | | | | | | Hypertension | 185(79.39) | 110(79.13) | 130(78.78) | 105(80.15) | .993 | | | Diabetes mellitus | 84(36.05) | 41(29.49) | 49(29.69) | 45(34.35) | .445 | | | Hyperlipidemia | 71(30.47) | 36(25.89) | 35(21.21) | 29(17.57) | .144 | | | Smoking | | | | | .008 | | | Current | 28(12.01) | 33(23.74) | 21(12.72) | 21(16.03) | | | | Prior (stopped ≥1y ago) | 93(39.91) | 43(30.93) | 58(35.15) | 44(33.58) | | | | Never smoked | 102(43.77) | 61(43.88) | 78(47.27) | 53(40.45) | | | | Not documented | 10(4.29) | 2(1.43) | 8(4.84) | 13(9.92) | | | | Atrial fibrillation | 30(12.87) | 20(14.38) | 35(21.21) | 35(26.71) | .004 | | | Congestive cardiac failure | 18(7.72) | 8(5.75) | 18(10.90) | 18(13.74) | .096 | | | Coronary heart disease (MI) | 26(11.15) | 14(10.07) | 23(13.9) | 25(19.08) | .107 | | | Depression | 54(23.17) | 40(28.77) | 47(28.48) | 53(40.45) | .006 | | | Stroke characteristics⁎ | | | | | | | | Stroke type | | | | | .006 | | | Hemorrhagic | 35(15.02) | 19(13.6) | 26(15.75) | 21(16.03) | | | | Ischemic | | | | | | | | Thrombotic | 153(65.66) | 100(71.94) | 96(58.18) | 64(48.85) | | | | Embolic | 33(14.16) | 15(10.79) | 40(24.24) | 39(29.77) | | | | Carotid occlusion with stroke | 9(3.86) | 3(2.15) | 3(1.81) | 6(4.58) | | | | Acute, ill defined | 3(1.28) | 2(1.43) | 0(0.00) | 1(0.76) | | | | Stroke site | | | | | <.001 | | | Left hemisphere | 50(21.45) | 39(28.05) | 53(32.12) | 94(71.75) | | | | Right hemisphere | 110(47.21) | 65(46.76) | 65(39.39) | 21(16.03) | | | | Bilateral hemisphere | 19(8.15) | 10(7.19) | 31(18.78) | 13(9.92) | | | | Brainstem: cerebellar | 44(18.88) | 19(13.66) | 12(7.27) | 2(1.52) | | | | Combined supra- and infratentorial | 7(3.00) | 4(2.87) | 3(1.81) | 1(0.76) | | | | Acute stroke ill defined | 3 | 2 | 1 | | | | | Stroke severity | | | | | | | | MMSE | 26.97±1.61 | 22.67±1.10 | 16.26±2.92 | 2.29±2.99 | <.001 | | | Visual field⁎ | | | | | <.001 | | | Normal | 201(86.26) | 100(71.94) | 94(56.96) | 57(43.51) | | | | Left homonymous hemianopsia | 16(6.86) | 26(18.70) | 37(22.42) | 10(7.63) | | | | Right homonymous hemianopsia | 4(1.71) | 2(1.43) | 22(13.33) | 51(38.93) | | | | Left visual neglect | 11(4.72) | 8(5.75) | 9(6.66) | 2(1.52) | | | | Right visual neglect | 0(0.00) | 3(2.15) | 2(1.21) | 8(6.10) | | | | Undetermined | 1(0.42) | 0(0.00) | 1(0.60) | 3(1.52) | | | | UE Motricity Index | 57.66±37.32 | 51.12±37.90 | 55.78±38.95 | 39.15±38.52 | <.001 | | | LE Motricity Index | 66.79±30.90 | 60.33±32.66 | 59.65±35.84 | 46.91±35.30 | <.001 | | | Limb placement task | 4.09±3.14 | 4.46±3.23 | 5.74±4.01 | 8.67±4.49 | <.001 | | | Impairments⁎ | | | | | <.001 | | | Motor only | 143(61.37) | 72(51.79) | 66(40.00) | 20(15.26) | | | | Motor + sensory | 19(8.15) | 11(7.91) | 10(6.06) | 34(25.95) | | | | Motor + vision | 15(6.43) | 21(15.10) | 24(14.54) | 21(16.03) | | | | Motor + sensory + vision | 15(6.43) | 13(9.35) | 41(24.84) | 48(36.64) | | | | Other | 5(2.14) | 4(2.87) | 7(3.03) | 8(6.10) | | | | Normal | 36(15.45) | 18(12.94) | 17(10.30) | 0(0.00) | | | | Functional history | | | | | | | | Admission FIM cognitive score | 26.73±3.59 | 24.62±3.75 | 20.63±4.47 | 14.59±4.35 | <.001 | | | Admission FIM total score | 69.98±15.19 | 64.84±16.82 | 55.03±18.40 | 43.73±15.84 | <.001 | | | | |
Cardioembolic stroke was more prevalent in patients with moderate (24.24%) and severe (29.77%) cognitive impairment compared with the cognitively intact group (14.16%) (P=.006). Similarly, left cerebral hemisphere involvement varied from 28.05% in the mild cognitively impaired group to 72% in the severe cognitively impaired group, compared with 21% in the cognitively intact group (P<.001). Patients with cognitive impairment had more severe strokes based on the degree of neurologic impairment(s) (motor, visual, sensory), both individually and collectively (P<.001). The primary outcome measures of the cognitively intact and the 3 cognitively impaired groups are presented in table 2. The change in FIM total score was similar across all 4 groups (P=.573); however, change in the FIM cognitive subscore was greatest in patients with severe cognitive impairment (3.06) and least in patients with mild cognitive impairment (1.20) and the cognitively intact group (1.38) (P<.001). The mean LOS was 22.62±11.07 days. LOS was longer in cognitively impaired patients compared with the cognitively intact patients; this was most obvious in patients with severe cognitive impairment (P<.001). FIM efficiency was higher in the cognitively intact compared with the 3 cognitively impaired groups of patients but was not statistically significant (P=.058). Patients in the 3 cognitively impaired groups made slower rehabilitation progress (<1 FIM point change per day) for the same intensity of rehabilitation therapy. Seventy-seven percent of cognitively intact patients were discharged home, as compared with discharges to home of 73% of the mildly cognitively impaired patients, 55% of the moderately impaired, and 45% of the severely impaired (P<.001). The numbers of patients who were discharged to a subacute facility or were transferred to acute care or assisted living were, respectively, as follows: cognitively intact (38/10/5), mild cognitive impairment (32/3/2), moderate cognitive impairment (61/12/0), and severe cognitive impairment (62/10/0). Linear regression analysis identified predictors of functional outcome measures. The change in FIM total score was affected by age (P<.001) and admission FIM total score (P<.001), but was not affected by the presence of depression (P=.46) or the admission MMSE score (P=.06). Similarly, younger age (≤69y), female sex (P=.001), and admission FIM total score (P<.001) were positively associated with home discharge. In 79% of the cases, admission FIM total score correctly predicted discharge disposition; however, when the model was rerun without admission FIM total score, 70% of the cases were correctly predicted (model correctly predicted 88% of the home discharges but only 37% of not-to-home discharges). Home discharge was negatively associated with older age (≥70y) and cortical involvement (P=.004), which meant that these patients were less likely to be discharged home. Similar sets of results were obtained for demographic variables and functional outcome measures in patients with ischemic stroke (n=567) when analyzed separately, and were comparable to the data set of all our stroke patients. For patients with hemorrhagic strokes (n=101), demographic variables such as smoking, presence of depression, and atrial fibrillation did not reach statistical significance. Similarly, changes in the FIM cognitive subscore and LOS were not statistically significant. The magnitude of the effect size for change in FIM cognitive subscores from admission to discharge post-treatment was −.46 for normal versus severe cognitive impairment, and −.54 for mild versus severe cognitively impaired patients. The effect size for change in FIM motor subscores was .27 for normal versus moderately cognitively impaired patients. The effect size for LOS was −.55 for normal versus severely cognitively impaired patients, −.41 for mildly versus severely cognitively impaired patients, and −.36 for moderately versus severely cognitively impaired patients. The effect size for discharge disposition was 32% in normal versus severely cognitively impaired patients. Thus, changes in the FIM cognitive subscores and LOS had the greatest effect size, greater than change in the FIM motor subscores and in discharge disposition. Discussion The principal finding of this study is that cognitively impaired patients benefit from admission to an acute rehabilitation stroke unit. Cognitively impaired patients achieved an improved level of functional independence (change in the FIM total score and FIM cognitive and motor subscores) and home discharge. The amount of change in FIM total score was similar between the cognitively intact and the 3 cognitively impaired patient groups. Those 3 groups, however, required a longer LOS to achieve the same benefit. FIM efficiency was therefore lower. Linear regression analysis of our data showed the change in FIM total score was influenced by age and admission FIM total score, but not by cognition on admission (MMSE score) or the presence of depression. Improvement in cognition was most marked in the moderately and severely cognitively impaired patient groups (change in FIM cognitive subscore). This finding is in agreement with those of other studies that used the MMSE-based cognitive evaluation.20, 50, 51 Home discharge was achieved by 78% of cognitively intact patients and by 73% of mildly impaired, 57% of moderately impaired, and 43% of severely impaired patients in our study. Age, admission FIM total score, and cortical involvement influenced discharge disposition. Patients older than 70 years with cortical involvement were less likely to be discharged home. Younger patients, especially females, with higher admission FIM total scores were more likely to be discharged home. In a recent study of 272 stroke patients admitted to 11 large-volume Veterans Affairs hospitals, Zinn et al52 found cognitively impaired patients performed poorly on instrumental daily living tasks at 6-month follow-up despite having equal access to, and the quality of, rehabilitative care. These results are less applicable to the general population because Zinn’s stroke patient population included mostly male veterans and lacked documentation of depression in more than 50% of the sample size; in addition, patients were excluded from their rehabilitation program if they had a severe stroke and cognitive impairment, defined as an inability to follow 2-step commands. Our study adds to the findings of Zinn’s study by being similar for age while incorporating both male and female stroke patients, and documents depression in all patients. In our study, 65% of the patients admitted with stroke had cognitive impairment. Ozdemir et al53 found that 79% of 45 poststroke patients had cognitive impairment, as determined by their MMSE scores. The fact that our patients with left-dominant hemisphere stroke tended to be more cognitively impaired could be due in part to the MMSE being language-based. Cardioembolism was the most frequent stroke type in the cognitively impaired group, often associated with atrial fibrillation. In this study, atrial fibrillation was the most common risk factor for the 3 cognitively impaired groups. One other study54 has shown a similar high incidence (73%) of cortical functional deficit in stroke patients due to cardioembolism. Cognitive impairment after stroke has more often been associated with small vessel ischemic disease and subcortical lacunar infarcts.17, 55, 56 Community-based studies of risk factors for cognitive impairment have shown an association with hypertension and diabetes.57, 58 In our rehabilitation hospital population, the rates for these risk factors were similar between the cognitively intact and the 3 cognitively impaired groups. Although the cognitively impaired groups had more physical impairments and disability compared with the cognitively intact group, there was no relation between the severity of cognitive impairment and severity of physical impairment in our study. Zinn et al59 found a similar lack of a relation between severity of cognitive impairment and physical impairment. Age, sex, and ethnicity were similar for the cognitively intact and the 3 cognitively impaired groups. Depression influences cognitive state. In this study, 29% of our patients were considered to be depressed during their inpatient stay. This percentage is similar to that in other poststroke depression studies in an acute rehabilitation unit.60 In our study, 23% of the cognitively intact patients had depression, compared with 28% in the moderately and 40% in the severely cognitively impaired groups. Depression, which has been increasingly associated with left-hemisphere lesions,61 was confirmed by this study. Involvement of left hemisphere−based language, praxis, and mood may explain this apparent link between cognitive impairment and depression. Study Limitations and Strengths This study has several limitations. First, we did not collect information about the premorbid cognitive status of the patients and consequently, baseline cognitive status was unknown. Second, less than 5% of the patients had recurrent strokes. It has been shown that cognitive impairment is more prevalent in recurrent than in initial stroke.62 Third, we did not address the variables known to influence home discharge, such as having a caregiver at home, or family and social support. Fourth, we did not classify specific domains of cognitive impairment, such as language, memory, or executive functions, nor did we focus on specific treatment modalities or the intensity of the therapies. Fifth, we are unable to ascertain whether improvement in the FIM cognitive score was the result of improvement in depression state or improvement in cognitive state because follow-up depression scores were not available. Finally, and this may also be an advantage, the data presented were collected prospectively by clinicians in the context of routine clinical care, and therefore reflect real-life practice. Strengths of this study are: a complete data set of a large sample size of all patients referred to an inpatient rehabilitation facility; recording of depression among inpatients; the assessment of cognitive impairment and its varying degree of severity; and the use of simple assessment scales, such as the MMSE and FIM, which are recognized to be of clinical relevance. Additionally, we have shown that cognitive impairment does not prevent stroke patients from benefiting from acute rehabilitation. Clinicians caring for acute stroke patients should routinely screen for cognitive impairment because it does have an impact on the level of independent functioning, irrespective of the presence or absence of physical impairments. The MMSE, despite its limitations, is an easy-to-administer and widely validated bedside screen for cognitive functioning. Conclusions Our results suggest that functional outcome and discharge disposition are not solely dependent on physical impairment(s) but also on cognitive impairment. Cognitively impaired patients, irrespective of the severity of the impairment, do benefit from rehabilitation programs and should have the same access to acute rehabilitation as do cognitively intact stroke patients. Supplier References 1. 1Luxenberg JS, Feigenbaum LZ. Cognitive impairment on a rehabilitation service. Arch Phys Med Rehabil. 1986;67:796–798. MEDLINE 2. 2Hamilton BB, Granger CV. Disability outcomes following inpatient rehabilitation for stroke. 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a Burke Rehabilitation Hospital, an affiliate of Weill Medical College of Cornell Medical College, White Plains, NY b Weill Medical College of Cornell University at the Hospital for Special Surgery, New York City, NY.  Reprint requests to Meheroz H. Rabadi, MD, MRCPI, Burke Rehabilitation Hospital, an affiliate of Weill Medical College of Cornell Medical College, 785 Mamaroneck Ave, White Plains, NY 10605
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated. PII: S0003-9993(07)01804-7 doi:10.1016/j.apmr.2007.11.014 © 2008 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved. | |
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