African Americans and Women have Lower Functional Gains during Acute Inpatient Rehabilitation after Hemorrhagic Stroke

Abstract

Objective

Intracerebral hemorrhage (ICH) can lead to significant long-term disability. While research in stroke rehabilitation has focused primarily on ischemic strokes, identifying factors that impact recovery in patients with ICH is necessary. Our purpose is to identify factors, including racial and sex disparities, associated with functional outcomes in ICH patients following inpatient rehabilitation.

Design

This was a retrospective analysis of consecutive patients with ICH admitted to an inpatient rehabilitation facility (IRF) at an academic tertiary facility in the Southeastern US from 2016–2019. Clinical characteristics, demographics, admission and discharge Functional Independence Measure (FIM) scores were collected.

Results

We evaluated 59 patients (54.4 ± 14.1 years, 39% females, 48.2% African American) with a median (IQR) ICH volume of 13.4 (4.2, 33.0), and a mean (SD) FIM efficiency of 1.8 ± 1.3. In multiple regression, being female was negatively associated with FIM efficiency (β=−1.13, p = 0.0037) when adjusting for race and ICH score. The FIM efficiency was lower in African Americans (β =−0.97, p = 0.0119) when adjusting for sex and ICH volume.

Conclusion

The results of our study indicate that FIM efficiency was worse for African Americans and female patients with ICH. Future research should consider these racial and sex disparities and focus on providing targeted rehabilitation therapy.

INTRODUCTION

Stroke, whether ischemic or hemorrhagic, can lead to significant clinical disabilities¹. Intracerebral hemorrhage (ICH) accounts for 15% of acute stroke in North America and Europe². For those who survive, ICH is associated with high morbidity, prolonged hospital stays and significant health care resource allocation³. A large proportion of these patients remain critically ill requiring ventriculostomy drain placement and mechanical ventilation, thus experiencing prolonged periods of bed rest making their rehabilitation particularly challenging.

Prior research has uncovered numerous predictors of poor functional outcome, including bowel and urinary incontinence, longer interval between stroke onset and hospital admission, more severe hemiparesis upon admission, visuospatial deficits and lower Functional Independence Measure (FIM) admission score¹. Many of these predictors can be determined prior to rehabilitation admission hence indicating that quality of life can be predicted earlier in a patient’s recovery course⁴. There have also been recent studies highlighting the association between gait function assessed during rehabilitation with 3-month functional outcomes after ischemic stroke⁵. Most of these studies identifying such predictors include both ischemic and hemorrhagic strokes and individual studies on ICH patients are limited. While there have been multiple studies on early rehabilitation^{6 7}, there is limited data on patient factors, including sex and racial differences associated with inpatient rehabilitation after ICH.

The aim of this present study was to determine what patient related factors impact progress in acute rehabilitation after ICH.

METHODS

Participants

This is a retrospective study of patients (≥18 years) who were consecutively admitted to a tertiary care center followed by inpatient rehabilitation facility (IRF) from December 2016 through December 2019 with primary diagnosis of ICH. All cases were confirmed on neuroimaging with CT or MRI. We excluded patients without neuroimaging, availability of rehabilitation measures, or stroke due to subarachnoid, subdural, or epidural hemorrhage or ischemic stroke (Supplemental Flow Diagram, Supplemental Digital Content 1, http://links.lww.com/PHM/B514). Institutional Review Board approval was obtained as a part of our Institutional Stroke Registry. No written informed consent was needed as this is a retrospective observational study. This study conforms to all STROBE guidelines and reports the required information accordingly (see Supplementary Checklist, Supplemental Digital Content 2, http://links.lww.com/PHM/B515).

ICH and hospital variables

We evaluated the following items in our patients with ICH: age, race, sex, pre-hospital living status, total number of inpatient days, duration of inpatient rehabilitation days, ICH score, and hematoma volume. The hematoma volume was calculated using the initial CT images on admission as follows: major axis of hematoma x minor axis x height x ½ (mL)⁸.

Outcome measures

Functional impairment was determined by an experienced physiatrist at the time of admission to the rehabilitation program and at discharge from hospital using the Functional Independence Measure (FIM) manual version 3.0, which contains 18 items divided into 6 domains covering activities of daily living, sphincter control, transfers, locomotion, communication and social cognition⁹. Each item is scored on an ordinal 7-point scale, where a score of 1 indicates total dependency and 7 indicates complete independence, The FIM total sum score ranges from 18 to 126 and can be divided into a motor (13 items) and a cognitive (5 items) subscore¹⁰. The FIM has proven content and construct validity, is responsive to small increments in functional status after stroke, and correlates highly with measures of neurologic impairment after stroke, such as the National Institutes of Health Stroke Scale¹¹. The FIM instrument was administered by certified and trained team members at admission and discharge. Functional gains were determined by comparing admission and discharge FIM scores. FIM Efficiency was defined as the change in functional status (total FIM) from admission to discharge divided by the duration of rehabilitation¹²; the shorter the duration for a given change in FIM rating, the higher the efficiency rating.

Duration of inpatient rehabilitation was defined as the number of days on which intensive rehabilitation was provided. Patients received at least 3 hours of rehabilitation therapies (occupational, physical, and speech) each day in an accredited program. Primary outcome measures were the patients’ change between admission and discharge FIM scores. Secondary outcome measures were FIM efficiency (FIM divided by number of days in rehabilitation), motor and cognitive subscores of FIM total score.

Statistical analysis

Baseline characteristics of the participants are described as means and standard deviations (SD) or medians and interquartile ranges (IQR) for continuous variables and frequencies for categorical variables. The difference in mean FIM score change as well as FIM efficiency was tested using two-sample t-tests. The association of predictors of interest with FIM efficiency was tested using multiple linear regression model. The predictors added into the model were decided a priori and included age, sex, race (African-American vs. non-African-American), location of ICH, hypertension as etiology (yes/no), and ICH volume. The β estimates and corresponding p-values under the significance level of α=0.05 are reported. All analyses were performed in SAS, version 9.4 (Cary, NC, USA).

RESULTS

The analysis included 59 patients who met the inclusion criteria. In this cohort, mean age was 54 years and 39% were females. The demographic and clinical characteristics of the study sample are shown in Tables 1. The cohort had a similar number of White and African-American patients with a small minority of ‘other’ patients which included Hispanics and Asians. The majority of our patients had deep subcortical (54.2%) ICH. The most common etiology for ICH was hypertension (62.7%). ICH volume was moderate sized with a mean of 13 ml. There were no significant differences among groups in relation to admission FIM scores or length of stay.

Table 1.

Participant characteristics

Variables	All participants
N	59
Age, mean ± SD	54.4 ± 14.1
Female, N(%)	23 (39.0%)
Race (missing=3)
White	26 (46.4%)
African-American	27 (48.2%)
Other	3 (5.4%)
Recurrent hemorrhage, N(%)	9 (15.3%)
Etiology, N(%)
Hypertension	37 (62.7%)
Vasculitis	1 (1.7%)
Mycotic aneurysm	4 (6.8%)
CAA	5 (8.5%)
Vascular malformation	7 (11.9%)
Trauma	1 (1.7%)
Coagulopathy	2 (3.4%)
CVST	2 (3.4%)
Location, N(%)
Deep	32 (54.2%)
Lobar	26 (44.1%)
Both	1 (1.7%)
ICH volume, median (IQR)	13.4 (4.2, 33.0)
Length of stay, days, median (IQR)	10.0 (7.0, 18.0)
Admission FIM	48.8 ± 15.8
Discharge FIM	73.7 ± 17.8
Change in FIM
Total	23.9 ± 13.7
Cognition	6.5 ± 5.1
Motor	14.2 ± 13.5
FIM efficiency	1.8 ± 1.3

FIM, functional independence measures; SD, standard deviation, HTN, hypertension; ICH, intracerebral hemorrhage; IQR, interquartile range; CAA, cerebral amyloid angiopathy; CVST, cerebral venous sinus thrombosis

Table 2 demonstrates the mean FIM change from admission to discharge and FIM efficiency for patient factors. Age was dichotomized to <50 and >=50 to identify stroke in the young population, however the differences were not statistically significant. Similarly, ICH location and etiology also did not show any differences. Mean FIM change and FIM efficiency were both lower for females when compared to males, with statistically significant p-values. In addition, FIM efficiency was also lower for African-American patients when compared to White patients.

Table 2.

Average change in functional independence measure (FIM) scores and average FIM efficiency by different participant characteristics

	Mean FIM change ± SD	p-value	Mean FIM efficiency ± SD	p-value
Age, n(%)
<50	24.2 ± 14.1	0.9075	2.0 ± 1.4	0.4389
≥50	23.8 ± 13.7		1.7 ± 1.3
Sex
Female	18.7 ± 15.4	0.0160	1.3 ± 0.9	0.0270
Male	27.5 ± 11.2		2.1 ± 1.5
Race
African-American	20.5 ± 13.7	0.0966	1.4 ± 0.9	0.0395
Non-AA	26.6 ± 13.3		2.1 ± 1.6
Location
Deep	24.9 ± 14.0	0.5070	1.7 ± 1.4	0.8289
Lobar	22.3 ± 13.5		1.9 ± 1.3
Botha	37.0		1.8
Etiology
Hypertensive	24.5 ± 12.8	0.7075	1.7 ± 1.3	0.3207
Non hypertensive	23.0 ± 15.3		2.0 ± 1.4

FIM, functional independence measures; SD, standard deviation; non-AA, non-African American

Statistical significance assessed using two-sample t-tests or ANOVA test for both outcomes

^aMean reported without SD because only one participant is in this category.

Multiple linear regression analysis with the β estimates and p-values for select predictors on FIM efficiency is displayed in Table 3. FIM efficiency was significantly lower in females compared to males when adjusting for other variables (β= −1.1320; p= 0.0037). In addition, FIM efficiency was significantly lower among African-Americans compared to non-African Americans when adjusting for other covariates. No significant differences were noted in FIM efficiency by age, ICH location, etiology, and ICH volume.

Table 3.

Effect of select predictors on FIM efficiency

Variables	β*	p-value
Intercept	4.9498	0.0001
Age	−0.0187	0.1306
Female	−1.1320	0.0037
African American	−0.9727	0.0119
Location	0.2072	0.6047
Hypertension as etiology	−0.2484	0.5888
ICH volume	−0.0102	0.1879

^*The β estimates and p-values obtained from multiple linear regression analysis

The referent is a non-AA male patient (age=0) with lesion location=deep and etiology other than hypertension and ICH volume=0

DISCUSSION

The main purpose of this study was to identify the patient-related characteristics that affect functional independence in patients diagnosed with ICH receiving care at an IRF. We found that sex and race were significant predictors of functional performance with female and African American patients having worse FIM efficiency during rehabilitation.

While there are multiple studies on rehabilitation after ischemic stroke; to our knowledge, there are no studies currently which highlight the differences in patient demographics that affect rehabilitation in patients with ICH alone. There is scant research on functional outcome differences in those with hemorrhagic versus ischemic strokes. The data is relatively mixed, however, it is generally believed that hemorrhagic stroke survivors have better neurological and functional prognoses than non-hemorrhagic stroke survivors¹. Previous studies suggest that within the first two months after stroke, spontaneous neurological recovery does occur¹³. There are also reports of an association between specific infarct lesion location volume and subsequent FIM scores assessed in inpatient rehabilitation¹⁴. In ICH particularly, with the alleviation of hematoma and edema, the brain can partially, or in rare cases fully, restore its function. However, the extent of functional recovery for most patients is limited and therefore intense rehabilitation and factors that affect this intervention can be important⁸. Petrushevichene et al. reported some factors, including male sex, young age, and hemorrhage as positive predictors of functional outcome in early rehabilitation¹⁵. Some other studies have identified longer length of stay and admission FIM cognitive score as predictors of total discharge FIM score recovery¹⁶. Because there are racial and ethnic differences in the incidence, type and severity of stroke, it is logical to presume that there may be racial and ethnic differences in post-acute care outcomes¹³.

There have been only a few studies identifying these racial disparities in this patient population. Bhandari et al. found that black ischemic stroke/ICH patients did not show as much functional gain from inpatient rehabilitation as whites yet were more likely to be discharged home¹⁷. Previous investigations of rehabilitation services with hip fracture found that black patients were more likely to receive lower intensities of physical and occupational therapy than nonblacks¹⁸. Another study by Burke et al concluded that black patients with ischemic stroke/ICH have 30% lower 30-day mortality than white patients with stroke, but greater short-term disability¹⁹. In this study, however, this cannot be compared as, to the best of our knowledge, all our patients received similar intensity of rehabilitation services.

There are several potential reasons why we see differences in FIM scores and FIM efficiency between racial and sex groups after controlling for ICH factors including volume, score, and location. While there have been studies demonstrating the impacts of socioeconomic status and educational level on rehabilitation²⁰, this would have little direct impact over a relatively short period of inpatient rehabilitation stay. There is limited research on this topic, with one investigation that reported variation in the type and amount of occupational and physical therapy provided to older adults based on racial grouping after controlling for level of disability and medical diagnosis²¹. This could point towards an implicit bias many physicians or therapists may hold in differentiating between African-Americans and other races. Other biological factors could also contribute towards this finding including comorbidities like obesity or end stage renal disease which would require the patient to spend many hours per week in dialysis. However, these variables were not collected and are beyond the scope of this study.

Sex is also a principal component. A Northern California study showed that women with a hemorrhagic stroke were less likely to receive inpatient rehabilitation and had more likelihood of being discharged to a skilled nursing facility²². Women experience increased difficulties with stroke recovery due to higher burden of pre-morbid disabilities and longer life-span which renders a more difficult recovery and increases their vulnerability for functional decline ²³. A previous study has also showed that hormonal changes, including a decline in estrogen and subsequent androgen excess make women more susceptible to the development of cardiovascular risk factors²⁴. In addition, women are more likely to report depression after a stroke, a factor that has a profound impact on the rate and quality of recovery²⁵. This study confirms that being female is a major factor in post-stroke FIM outcomes.

Other possible explanations include socio-behavioral factors such as attitudes toward health services, incentive to engage in the demanding activities associated with medical rehabilitation, and compliance with treatment programs and exercises²⁶. Assessing the independent effect of race on medical care also requires adjusting for differences in attitudes and beliefs regarding the efficacy of medical care²⁷. An important component of these beliefs is individuals’ perceived ‘health locus of control’, a construct from social learning theory that refers to whether health and health outcomes are under individuals’ personal control, or chance¹⁸. This study showed that blacks had stronger beliefs than whites regarding the importance of luck as a factor in health outcomes whereas internal locus of control has been identified as a predictor of rehabilitation motivation and treatment success²⁸.

Research on the clinical significance of FIM score changes have shown that each 1-point increase in the total FIM rating is associated with an average of between 3–6 minutes of daily help required from another person²⁹. If an average of 4 minutes per FIM point is considered, the difference at discharge of almost 9 FIM points between males and females translates to 4.2 hours per week of assistance provided by another person. Similarly, the difference of 6 FIM points between blacks and non-blacks translates to approximately 3 hours per week of additional help needed. Targeted interventions, including focusing on length of stay, type, duration, and intensity of therapy offered, and understanding the attitudes towards health services held by patients and their families, are needed to address these disparities. Another option could be discharge to a skilled nursing facility – potentially a short stay - prior to being discharged home. While this might be reviewed less favorably in this sociodemographic group, less intensive care in a SNF will contribute to the important post-stroke recovery in the subacute phase while ensuring patient safety and care.

Study limitations

There are several limitations to this study. This is a retrospective investigation of a large academic center in the Stroke Belt, and the ICH population would not reflect all centers. There is also potential selection bias as only those who could tolerate rehabilitation post-stroke were included. Thus, our small sample does not include patients with minor or severe impairments. The present study was comprised of a relatively young sample. In some studies, age was found to be a predictor of functional outcome after rehabilitation, particularly regarding activities of daily living³⁰; in the present study, patients might have exhibited better outcome overall due to younger age at the time of ICH. Also, while we do report the racial and sex disparities in our study, we did not identify the mechanisms by which observed disparities emerge. Variables like patient satisfaction, family support, and genetic differences were unmeasured, leading to possibility of confounding. Another limitation is the lack of data on follow-up services of this population – this would be useful to determine if this disparity in discharge setting persists over time or if there are differences in downstream institutional placement or hospitalization readmission across racial/ethnic groups¹⁶.

CONCLUSION

The results of this study indicate that females and African American patients with ICH have significantly less functional improvement after acute inpatient rehabilitation. While sexual and racial differences likely play a part in this difference, it is important to identify other modifiable factors like implicit bias by healthcare workers and socio-behavioral factors. Future research in understanding the mechanistic differences in functional outcomes among racial and sex differences are warranted. In addition, further research should also examine social support systems to determine the impact of social support on functional outcome in participants¹.

What is Known?

There are some studies on rehabilitation after ischemic stroke or mixed ischemic and intracranial hemorrhage strokes. There are only a few studies identifying racial and sexual disparities in rehabilitation after ischemic stroke.

What is New?

There are no prior studies to identify patient related characteristics that affect functional independence in patients with ICH who undergo acute rehabilitation at an inpatient rehab facility. There are also limited studies on FIM efficiency as an objective variable to determine these differences.