Incidence, risk factors, and outcomes of fecal incontinence after acute brain injury: Findings from the traumatic brain injury model systems national database

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Incidence, Risk Factors, and Outcomes of Fecal Incontinence After Acute Brain Injury: Findings from the Traumatic Brain Injury Model Systems National Database Amy Foxx-Orenstein, DO, Stephanie Kolakowsky-Hayner, MA, Jennifer H. Marwitz, MA, David X. Cifu, MD, Ann Dunbar, PT, MS, Jeffrey Englander, MD, Gerard Francisco, MD ABSTRACT. Foxx-Orenstein A, Kolakowsky-Hayner S, Marwitz JH, Cifu DX, Dunbar A, Englander J, Francisco G. Incidence, risk factors, and outcomes of fecal incontinence after acute brain injury: findings from the Traumatic Brain Injury Model Systems national database. Arch Phys Med Rehabil 2003;84:231-7. Objective: To investigate the incidence, risk factors, and outcome in patients with fecal incontinence after acute brain injury. Design: A retrospective study of the incidence of and risk factors contributing to fecal incontinence, and outcomes at admission to and discharge from inpatient rehabilitation and at 1-year follow-up. Setting: Medical centers in the federally sponsored Traumatic Brain Injury Model Systems (TBIMS). Participants: A total of 1013 consecutively enrolled rehabilitation inpatients from 17 TBIMS centers who were admitted to acute care within 24 hours of traumatic brain injury and seen at 1-year postinjury between 1990 and 2000. Interventions: Not applicable. Main Outcome Measures: Incidence of fecal incontinence, length of coma, length of posttraumatic amnesia (PTA), admission Glasgow Coma Scale (GCS) score, length of stay (LOS), FIM™ instrument scores, disposition at discharge and follow-up, and incidences of pelvic fracture, frontal contusion, and urinary tract infection (UTI). Results: The incidence of fecal incontinence was 68% at admission to inpatient rehabilitation, 12.4% at rehabilitation discharge, and 5.2% at 1-year follow-up. Analysis of variance and chi-square analyses revealed statistically significant associations between the incidence of fecal incontinence at rehabilitation admission and admission GCS score, length of coma and PTA, LOS, and incidence of UTI and frontal contusion. Fecal incontinence at rehabilitation discharge was significantly associated with several variables, including age, discharge disposition, admission GCS score, length of coma, PTA, LOS, FIM scores, and incidence of pelvic fracture and frontal contusion. Significant associations were also found between fecal incontinence at 1-year follow-up and age, discharge and cur-

From the Virginia Commonwealth University, Richmond, VA (Foxx-Orenstein, Kolakowsky-Hayner, Marwitz, Cifu, Dunbar); Santa Clara Valley Medical Center, San Jose, CA (Englander); and TIRR, Houston, TX (Francisco). Supported in part by the National Institute on Disability and Rehabilitation Research, US Department of Education (grant no. H133B80029) and the Irving I. and Felicia F. Rubin Family Brain Injury Research Fund. Data were contributed from the Traumatic Brain Injury Model Systems. 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 author(s) or upon any organization with which the author(s) is/are associated. Reprint requests to Jennifer H. Marwitz, MA, Dept of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Box 980542, Richmond, VA 23298-0542. 0003-9993/03/8402-7125$35.00/0 doi:10.1053/apmr.2003.50095

rent 1-year disposition, admission GCS score, length of coma, LOS, FIM scores, and incidence of UTI (P⬍.05). Although logistic regression analyses were significant (P⬍.001), and predicted continence with 100% accuracy, demographics, injury characteristics, medical complications, and functional outcomes did not predict incontinence at discharge and at 1-year follow-up. Conclusions: Fecal incontinence is a significant problem after brain injury. Certain factors may increase its likelihood. Further studies evaluating mechanisms of fecal incontinence and treatment or control interventions would be useful. Key Words: Brain injuries; Fecal incontinence; Incidence; Rehabilitation; Risk factors; Treatment outcome. © 2003 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation ECAL INCONTINENCE IS a silent disorder. The negative social stigmata that surround this condition leaves sufferers F and caretakers to cope quietly with their feelings of embarrassment, humiliation, and social isolation.1-3 The prevalence of the disorder is unknown because those affected are often unwilling or unable to speak of the problem, and physicians are unlikely to ask.4,5 Fecal incontinence is socially devastating, because when it happens, it is impossible to disguise. It is easier and more comfortable to avoid the potential incident. Incontinence is often overlooked or misinterpreted6 when, in fact, it may be associated with loose stool, normal stool consistency, or even constipation. This inadvertent loss of stool occurs because the normal continence mechanisms are overwhelmed and the ability to store material and selectively release gas or solid material is lost. Additionally, fecal incontinence has several medical consequences, including skin irritation, pressure ulcers, and skin infections. Limited literature exists on the incidence and risk factors for fecal incontinence in patients with brain injury. It is recognized early during hospitalization and is addressed by placing patients on bowel-management regimens that often include bulking and/or motility agents and timed elimination programs. Impaired cognition and neural control of evacuation contribute to fecal incontinence in the brain-injured patient. Its specific cause is not generally determined diagnostically, perhaps because bowel consistency is regimented soon after initial brain trauma, and factors contributing to incontinence may become less apparent. Incontinence in these patients may be exacerbated by various factors such as medications, diet, lack of access to bathroom facilities, lack of awareness of the need to defecate, and weak pelvic floor muscles. Incontinence may delay a patient’s discharge from an acute care facility and can substantially hinder a return to the home environment and a resumption of preinjury activities. To enhance representativeness, multicenter, longitudinal data collection methods were used7 at the National Institute on Disability and Rehabilitation Research (NIDRR) Traumatic Arch Phys Med Rehabil Vol 84, February 2003

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Brain Injury Model Systems (TBIMS) centers to address 3 primary objectives: (1) to identify the incidence of fecal incontinence after traumatic brain injury (TBI), (2) to identify the risk factors associated with fecal incontinence, and (3) to determine at 1-year postinjury the outcome in patients who have fecal incontinence. METHOD Participants and Data Source In 1987, NIDRR provided funding to establish the TBIMS, whose focus is on developing and showing a model system of care for persons with TBI and on maintaining a standardized national database for analyses of treatment and outcomes. For the purpose of the database, TBI is defined as injury to brain tissue caused by an external mechanical force, as evidenced by loss of consciousness from brain trauma, posttraumatic amnesia (PTA), skull fracture, or objective neurologic findings that can be reasonably attributed to TBI on physical or mental status examination. Criteria for inclusion in the database include (1) being at least 16 years old, (2) presentation to the emergency department of a TBIMS trauma center within 24 hours of injury, (3) receipt of acute care and inpatient rehabilitation at a participating center, and (4) consent to participate. Data were collected prospectively. The TBIMS database contains information on 1013 individuals who were consecutively enrolled in any of the 17 medical centers in the system. These centers represent geographically diverse regions of the United States, and each includes emergency medical services, intensive and acute medical care, inpatient rehabilitation, and a spectrum of community rehabilitation services. To improve sample representativeness, standardized protocols are used to provide for the inclusion of individuals with a previous brain injury, a preexisting neurologic condition, or a history of substance abuse. Demographic features of patients in the database are described elsewhere.7 Selected descriptive information about the present sample is reported in our Results section. Measures Measurement categories and evaluation protocols are described below. FIM™ instrument. The FIM™ instrument8 is an 18-item, 7-point scale on which higher values indicate greater levels of independence. The 18 items describe levels of self-care, continence, mobility, communication, and cognition.9-11 The following scores were calculated from the FIM: (1) FIM change: to determine absolute change, admission scores were subtracted from discharge scores, and admission and discharge scores were subtracted from 1-year follow-up scores, and (2) FIM efficiency: to control for variation in length of stay (LOS), FIM change was divided by LOS. Fecal incontinence. Fecal incontinence was defined as a score of less than 5 on the bowel-management subscale of the FIM instrument; this subscale indicates total, maximum, moderate, or minimum assistance needed. Bowel management includes intentional control of bowel movements and, if necessary, use of equipment or agents for bowel control.8 Glasgow Coma Scale. Glasgow Coma Scale (GCS) admission score (as recorded by a physician when the patient is admitted to the emergency department) was used as a measure of injury severity. To determine an accurate GCS score for subjects who were intubated, we used the conversion formula established by Choi et al.12 Duration of coma. Coma was defined as a GCS motor score of less than 6. Duration of coma was calculated based on Arch Phys Med Rehabil Vol 84, February 2003

the time elapsed between onset of injury and the time each patient was able consistently to follow commands (GCS motor score⫽6). Duration of PTA. The Galveston Orientation and Amnesia Test (GOAT) was used to assess orientation and PTA. Duration of PTA was measured by calculating the number of days that elapsed between the onset of injury and the date that the first of 2 consecutive GOAT scores was greater than 75. Disposition. This is a dichotomous classification that indicates whether patients were living at home or in institutional settings. Procedure A comprehensive program of inpatient rehabilitation was provided to patients, tailored to meet their needs and abilities. Within each center the following services were provided: nursing, occupational therapy, physiatry and related medical services, physical therapy, psychology and neuropsychology, recreation therapy, social services, and speech and language therapy. Admission decisions were based on the rehabilitation team’s perceptions of the patients’ rehabilitation needs, with approval from third-party payment sources. Information about medical aspects of the patients’ injuries was obtained from hospital records. Admission and discharge FIM scores were obtained within 24 hours of admission and 72 hours of discharge, respectively. Scores were determined by certified interdisciplinary team members by using the standard protocols established by the Uniform Data Set for Medical Rehabilitation.8 An annual follow-up interview is attempted with every person who entered data into the database. An in-person follow-up interview with the subject is the method of first choice. If this is not possible, a telephone interview is attempted; if this is unsuccessful, data are collected through a mail questionnaire and/or interview with a significant other or family member. Data Analysis Descriptive statistics were computed for all relevant variables. Data were examined based on incidence of fecal incontinence. Relationships between fecal incontinence and other variables were examined by using analyses of variance (ANOVAs). Where data were categoric, chi-square analyses were performed. Three forward-conditional stepwise multiple logistic regression analyses were conducted to predict patients’ continenceincontinence status: (1) admission variables predicting discharge incontinence, (2) admission variables predicting 1-year follow-up incontinence, and (3) discharge variables predicting 1-year follow-up incontinence. Variables were entered and removed from the model based on .05-entry and 1.0-removal criteria. Repeated execution of the estimation algorithms were terminated at iteration 9 for admission predicting discharge, 10 for admission predicting 1-year follow-up, and 8 for discharge predicting 1-year follow-up because the ⫺2Log likelihood values decreased by less than .01%. Significance was determined by using the Wald statistic. All categoric data were automatically recoded during the analyses by using the Helmert coding method. RESULTS Incidence and Risk Factors of Fecal Incontinence at Rehabilitation Admission On admission to inpatient rehabilitation, 68.3% of the sample presented with fecal incontinence. To determine the risk

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FECAL INCONTINENCE AFTER TBI, Foxx-Orenstein Table 1: Demographic Characteristics and Fecal Incontinence at Admission Variable

Incontinent

Mean age ⫾ SD (y) Gender, n (%) Male Female Ethnicity, n (%) Minority Nonminority Preinjury residence, n (%) Private Institution Homeless/hotel

Continent

35.8⫾16.3

35.1⫾14.6

498 (74.7) 169 (25.3)

240 (77.4) 70 (22.6)

289 (43.3) 978 (56.7)

140 (45.2) 170 (54.8)

643 (96.8) 8 (1.2) 13 (2.0)

303 (97.7) 1 (0.3) 6 (1.9)

NOTE. No significant differences were noted between groups. Abbreviation: SD, standard deviation.

factors of fecal incontinence on admission, demographics, injury characteristics, and medical complications were analyzed by incontinence group. Information about demographic characteristics for each incontinence group is provided in table 1. There were no significant differences between the 2 groups for age, gender, ethnicity, or preinjury residence. With regard to injury characteristics, ANOVAs revealed significant between-group differences for all variables analyzed (table 2), including admission GCS (F1,877⫽71.60, P⬍.001), duration of unconsciousness (F1,928⫽73.02, P⬍.001), duration of PTA (F1,660⫽71.64, P⬍.001), and admission FIM score (F1,923⫽998.75, P⬍.001). The incontinent group showed greater injury severity across all measures. Acute care LOS also differed significantly between the 2 groups (F1,976⫽77.26, P⬍.001) (table 2). On average, persons with fecal incontinence stayed 11 days longer in acute care than persons who were continent. Data were further examined to determine if relationships existed between incidence of comorbidities and conditions and fecal incontinence at rehabilitation admission. Incidence of pelvic fracture, frontal contusions to the brain, and urinary tract infections (UTIs) were included in analyses. With regard to admission fecal incontinence, chi-square analyses were statistically significant for frontal contusions (␹2⫽5.96, P⬍.05) and UTI (␹2⫽40.88, P⬍.001). Individuals who were incontinent at admission were more likely to have complications from frontal contusions (47% vs 36%) and UTI (33% vs 14%). The percentages of pelvic fractures were similar for persons who were continent (8%) or incontinent (10%) at admission. Incidence and Risk Factors of Fecal Incontinence at Rehabilitation Discharge At discharge, the percentage of patients with fecal incontinence decreased to 12.4%. Demographics, injury characteristics, and medical complications were examined to determine

their relation to incidence of fecal incontinence at rehabilitation discharge. Information about demographic characteristics for each rehabilitation discharge incontinence group is provided in table 3. Significant between-group differences were found in age (F1,973⫽5.42, P⬍.05) and residence at discharge (␹2⫽92.92, P⬍.001), but not in gender, ethnicity, or residence preinjury. Persons with fecal incontinence at discharge were, on average, 3.5 years older than persons who were continent at discharge. Further, persons who were continent were more likely to be discharged to a private residence than were persons who were incontinent. With regard to injury characteristics, ANOVAs revealed significant between-group differences for all variables analyzed (table 4), including admission GCS (F1,874⫽32.17, P⬍.001), duration of unconsciousness (F1,925⫽84.64, P⬍.001), duration of PTA (F1,662⫽28.89, P⬍.001), discharge FIM score (F1,947⫽1025.63, P⬍.001), FIM change from admission to discharge (F1,897⫽82.97, P⬍.001), and FIM efficiency (F1,897⫽139.39, P⬍.001). The incontinent group showed greater injury severity across all measures, as well as lower functional gains, and less efficiency. Also shown in table 4, acute care LOS (F1,973⫽206.74, P⬍.001) and rehabilitation LOS (F1,973⫽223.80, P⬍.001) differed significantly between the 2 groups. On average, persons with fecal incontinence at discharge stayed 24 more days in acute care, and 53 more days in inpatient rehabilitation than persons who were continent. The relation between incidence of medical complications and fecal incontinence at rehabilitation discharge was also examined (table 5). Incidence of pelvic fracture, frontal contusions to the brain, and UTIs were included in the analyses. With regard to discharge fecal incontinence, chi-square analyses were statistically significant for pelvic fractures (␹2⫽5.13, P⬍.05) and UTIs (␹2⫽40.38, P⬍.001). Individuals who were incontinent at rehabilitation discharge were more likely to have sustained a pelvic fracture or developed a UTI some time during their acute or rehabilitation LOS. Incidence and Risk Factors of Fecal Incontinence at 1-Year Follow-Up Incidence of fecal incontinence declined further at 1-year follow-up, to 5.2%. Demographics, injury characteristics, and medical complications were examined to determine their relation to incidence of fecal incontinence at 1-year follow-up. Table 6 lists the demographic characteristics for each incontinence group. Significant differences were found between the 2 groups in age (F1,877⫽71.60, P⬍.001), residence at discharge (␹2⫽5.96, P⬍.05), and residence at follow-up (␹2⫽40.88, P⬍.001). However, no significant differences were identified for gender, ethnicity, or residence preinjury. Persons with fecal incontinence at 1-year follow-up were, on average, 9 years older than persons who were continent. Persons who were continent at 1-year follow-up were more likely to have been discharged to a private residence rather than to an institution

Table 2: Injury Characteristics and Fecal Incontinence at Admission Variable

Incontinent (mean ⫾ SD)

Continent (mean ⫾ SD)

Significance

Admission GCS Duration of unconsciousness (d) Duration of PTA (d) Admission FIM Acute LOS (d)

8.0⫾4.0 13.8⫾25.1 39.9⫾28.3 40.5⫾18.4 26.2⫾21.1

10.4⫾3.8 3.8⫾5.9 20.3⫾29.0 80.4⫾16.7 15.1⫾10.3

F1,877⫽71.60, P⬍.001 F1,928⫽73.02, P⬍.001 F1,660⫽71.64, P⬍.001 F1,923⫽998.75, P⬍.001 F1,976⫽77.26, P⬍.001

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FECAL INCONTINENCE AFTER TBI, Foxx-Orenstein Table 3: Demographics, Discharge Disposition, and Fecal Incontinence at Rehabilitation Discharge Variable

Incontinent

Continent

Significance

Mean age ⫾ SD (y) Gender, n (%) Male Female Ethnicity, n (%) Minority Nonminority Residence preinjury, n (%) Private Institution Homeless/hotel Residence at discharge, n (%) Private Institution Homeless/hotel

38.6⫾17.5

35.1⫾15.4

F1,973⫽5.42, P⬍.05 NS

85 (70.2) 36 (29.8)

652 (76.4) 201 (23.6)

47 (38.8) 74 (61.2)

387 (45.4) 466 (54.6)

119 (98.4) 1 (0.8) 1 (0.8)

825 (97.1) 8 (0.9) 17 (2.0)

67 (55.4) 54 (44.6) 0 (0.0)

749 (88.6) 93 (11.0) 3 (0.4)

NS

NS

␹2⫽92.92, P⬍.001

Abbreviation: NS, not significant.

than were persons who were incontinent, and were more likely to live currently in a private residence. Concerning injury characteristics, ANOVAs revealed significant between-group differences for all variables analyzed (table 7), including admission GCS (F1,854⫽5.03, P⬍.05), duration of unconsciousness (F1,904⫽16.63, P⬍.001), follow-up FIM score (F1,904⫽1668.78, P⬍.001), FIM change from discharge to follow-up (F1,855⫽62.57, P⬍.001), and FIM change from admission to follow-up (F1,826⫽134.46, P⬍.001). A trend was also noted for duration of PTA (F1,650⫽3.70, P⬍.055). The incontinent group showed greater injury severity across all measures, as well as lower functional gains for both time periods. Acute care LOS (F1,952⫽112.04, P⬍.001) and rehabilitation LOS (F1,951⫽123.14, P⬍.001) differed significantly between the 2 groups (table 7). On average, persons with fecal incontinence at 1-year follow-up stayed 28 more days in acute care and 63 more days in inpatient rehabilitation than persons who were continent. Data were further examined to determine if relationships existed between incidence of medical complications and fecal incontinence at 1-year follow-up (table 8). Incidence of pelvic fracture, frontal contusions to the brain, and UTIs were included in the analyses. With regard to fecal incontinence, chi-square analyses were statistically significant only for UTI (␹2⫽29.41, P⬍.001). Individuals who were incontinent at follow-up were more likely to have contracted a UTI during their initial hospital stay.

Predicting Fecal Incontinence at Discharge and 1-Year Follow-Up Incontinence at discharge can be predicted by using the multivariate model that included acute LOS, rehabilitation LOS, admission GCS score, highest GCS score, lowest GCS score, length of coma, length of PTA, and Rancho Los Amigos Levels of Cognitive Functioning (RLA), whether a patient had frontal contusions, and whether a patient had a UTI (Wald statistic⫽145.01, P⬍.001). Overall, the percentage of persons who were correctly classified by the multivariate model was 92.8%. However, even though the correct prediction rate for continence was 100%, the prediction rate for incontinence was 0%. Similarly, the regression analysis predicting incontinence at 1-year follow-up from admission variables was significant using the same model described in the previous paragraph (Wald statistic⫽110.82, P⬍.001). Overall, the percentage of persons who were correctly classified by the multivariate model was 97.2%. Again, however, although the correct prediction rate for continence was 100%, the prediction rate for incontinence was 0%. The regression model predicting fecal incontinence from discharge variables at 1-year follow-up differed slightly in that it included age at injury and discharge residence. The results again indicate that the model (Wald statistic⫽109.99, P⬍.001) predicts the presence of incontinence at 1-year follow-up. Overall, the percentage of persons who were correctly classi-

Table 4: Injury Characteristics and Incontinence at Rehabilitation Discharge Variables

Incontinent (mean ⫾ SD)

Continent (mean ⫾ SD)

Significance

Admission GCS Duration of unconsciousness Duration of PTA Discharge FIM FIM change (discharge FIM ⫺ admission FIM) FIM efficiency (FIM change/rehabilitation LOS) Acute LOS Rehabilitation LOS

6.8⫾4.0 22.1⫾29.5 56.9⫾34.3 53.5⫾24.6 27.2⫾19.1 0.4⫾0.4 43.4⫾30.1 105.2⫾58.4

9.1⫾4.0 8.1⫾11.5 31.0⫾28.8 103.1⫾14.2 45.9⫾20.8 1.1⫾0.6 19.4⫾14.4 52.0⫾32.4

F1,874⫽32.17, P⬍.001 F1,925⫽84.64, P⬍.001 F1,662⫽28.89, P⬍.001 F1,947⫽1025.63, P⬍.001 F1,897⫽82.97, P⬍.001 F1,897⫽139.39, P⬍.001 F1,973⫽206.74, P⬍.001 F1,973⫽223.80, P⬍.001

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FECAL INCONTINENCE AFTER TBI, Foxx-Orenstein Table 5: Categoric Injury Characteristics and Fecal Incontinence at Discharge Incontinent, n (%)

Variable

Pelvic fractures Yes No Frontal contusions Yes No UTIs Yes No

Continent, n (%)

Significance

␹ ⫽5.13, P⬍.05 2

18 (15.0) 102 (85.0)

73 (8.6) 779 (91.4)

34 (41.0) 49 (59.0)

255 (43.7) 329 (56.3)

NS

␹2⫽40.38, P⬍.001 60 (49.6) 61 (50.4)

651 (76.9) 196 (23.1)

fied by the multivariate model was again 97.2%. However, as with the 2 previous analyses, although the correct prediction rate for continence was 100%, the prediction rate for incontinence was 0%. Although statistically significant, none of the 3 regression analyses were clinically significant. DISCUSSION In our study, more than two thirds of all individuals admitted to inpatient rehabilitation after TBI were bowel incontinent. This high incidence is not surprising given the significant cognitive and motor deficits that often result after moderate to severe TBI. In fact, the typical individual with TBI who is admitted to the TBIMS programs is functioning at an RLA level of between IV (agitated and confused) and V (confused and inappropriate), and requires assistance with even basic mobility skills, an indication of profound cognitive limitations.8 Fortunately, more than 82% of those incontinent at rehabilitation admission were able to regain continence by the time of rehabilitation discharge. Achievement of this goal is a basic foundation of any rehabilitation program. Similarly, by 1-year postinjury, an additional 60% of those incontinent at discharge progressed to continence. Although these dramatic improvements would be expected, considering the cognitive

and motor improvements noted after TBI, this study validates these assumptions. Not surprisingly, the only demographic feature associated with bowel incontinence was increased age. The associations noted between it and an increased incidence of bowel incontinence at rehabilitation discharge and 1-year follow-up may relate to several factors. Although physiologic changes from aging may influence gastrointestinal motility and continence, it is unlikely that the less than 10-year differences would have resulted in a clinically significant increase in incontinence. More likely, the greater cognitive and physical limitations in older adults after TBI would have contributed more directly to this finding. Other research13 has shown a greater degree of functional dependency in older adults after TBI associated with (1) the greater sensitivity of the older brain to injury, (2) the diminished functional reserve in the older adult, (3) an increase in concomitant illness with aging (eg, peripheral neuropathy), and (4) the predilection to greater medical complications (eg, UTIs) with increased age. Any or all of these factors may have influenced bowel incontinence. Additionally, an age bias may have existed, wherein it was more accepted that older adults would be bowel incontinent after TBI, therefore less intensive behavioral and functional interventions were carried out by care providers for older adults. As expected, indicators of increased severity of injury after TBI were associated with an increased incidence of bowel incontinence. Although there may be no direct relation between actual injury severity and continence, bowel continence is likely a functional deficit that reflects impaired cognitive and motor deficits. The association between injury severity and cognitive and motor functional deficits has been well defined.14,15 Thus, the increase in motor and cognitive deficits, seen with an increased injury severity, may explain persistent incontinence. Similarly, associations among acute and rehabilitation LOSs, functional deficits, functional improvement, functional improvement efficiency, and bowel incontinence may reflect injury severity and cognitive deficits. In short, bowel incontinence may be more of a marker of a significant brain injury.

Table 6: Demographics, Discharge Disposition, and Fecal Incontinence at 1-Year Follow-Up Variable

Incontinent

Continent

Significance

Mean age ⫾ SD (y) Gender, n (%) Male Female Ethnicity, n (%) Minority Nonminority Residence preinjury, n (%) Private Institution Homeless/hotel Residence at discharge, n (%) Private Institution Homeless/hotel Residence at follow-up, n (%) Private Institution Homeless/hotel

44.0⫾19.0 n% 37 (74.0) 13 (26.0)

35.0⫾15.3 n% 683 (75.6) 220 (24.4)

F1,877⫽71.60, P⬍.001 NS

22 (44.0) 28 (56.0)

339 (44.2) 504 (55.8)

49 (98.0) 1 (2.0) 0 (0.0)

875 (97.1) 8 (0.9) 18 (2.0)

26 (52.0) 24 (48.0) 0 (0.0)

771 (86.4) 119 (13.3) 2 (0.1)

28 (56.0) 22 (44.0) 0 (0.0)

834 (93.2) 58 (6.5) 3 (0.3)

NS

NS

␹2⫽5.96, P⬍.05

␹2⫽40.88, P⬍.001

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FECAL INCONTINENCE AFTER TBI, Foxx-Orenstein Table 7: Injury Characteristics and Incontinence at 1-Year Follow-Up Variables

Admission GCS Duration of unconsciousness (d) Duration of PTA (d) Follow-up FIM FIM change from discharge (follow-up FIM ⫺ discharge FIM) FIM change from admission (follow-up FIM ⫺ admission FIM) Acute LOS (d) Rehabilitation LOS (d)

Incontinent (mean ⫾ SD)

Continent (mean ⫾ SD)

Significance

7.5⫾4.2 19.3⫾30.7 49.5⫾28.4 41.4⫾24.3 ⫺3.8⫾26.2

8.9⫾4.0 9.5⫾14.4 32.6⫾30.2 117.7⫾10.9 17.8⫾16.5

F1,854⫽5.03, P⬍.05 F1,904⫽16.63, P⬍.001 F1,650⫽3.70, P⬍.055* F1,904⫽1668.78, P⬍.001 F1,855⫽62.57, P⬍.001

16.1⫾23.4

63.1⫾24.4

F1,826⫽134.46, P⬍.001

49.3⫾38.0 118.6⫾71.9

21.4⫾16.4 56.1⫾36.1

F1,952⫽112.04, P⬍.001 F1,951⫽123.14, P⬍.001

* Nonsignificant trend.

Although bowel incontinence after TBI may reflect global impairments associated with increased injury severity, rather than be directly caused by it, damage to the frontal lobes specifically could cause both increased injury severity and incontinence. Frontal lobe injuries, a common occurrence in TBI because of the relation between the skull and the predominance of frontward-occurring motor vehicle crashes, could result in a direct increase in the social control of bowel continence. The so-called “frontal defecation center” is believed to allow for voluntary (or social) control of defecation, providing an overriding pathway to monitor and control the need to defecate. Typically lacking in the infantile (poorly myelinated) and senile (demented) brain, this frontal lobe locus of continence is likely to be injured in many individuals with moderate or severe TBI, causing the noted high incidence of initial incontinence. It is not surprising, therefore, to find a significant association between increased frontal-lobe contusions and bowel incontinence. The improvement in almost all incontinent individuals attests to the extent and rapidity of recovery of this portion of frontal lobe functioning. The relationships noted among UTIs, pelvic fractures, and bowel incontinence may be related to overall injury severity or focal peripheral nerve injuries. Increased injury severity alone may result in all 3 conditions independently. Individuals with greater injury severity would be more likely to require indwelling Foley catheters, require longer intensive and acute care hospitalization stays, and receive antibiotics, all of which would increase their risk for UTIs. Similarly, fractures are more likely to occur in high speed and result in impact injuries of greater severity. Although these factors could occur independently, there may be direct associations. UTIs (and the factors that cause them) may predispose individuals to be Table 8: Categoric Injury Characteristics and Fecal Incontinence at 1-Year Follow-Up Variable

Pelvic fractures Yes No Frontal contusions Yes No UTIs Yes No

Incontinent, n (%)

Continent, n (%)

Significance

NS 6 (12.0) 44 (88.0)

81 (9.0) 820 (91.0)

14 (43.8) 18 (56.2)

270 (43.5) 350 (56.5)

30 (60.0) 20 (40.0)

225 (25.1) 673 (74.9)

NS

␹2⫽29.41, P⬍.001

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bowel incontinent, whether because of the gastrointestinal effects of the antibiotics used, or the increased perineal irritation associated with infection. Likewise, the pain associated with pelvic fractures and the effects of the pain medications used to treat the fractures (both the initial sedating effects and the long-term constipating effects) may result in bowel incontinence. Pelvic fractures can also result in lumbosacral plexus injuries that effect motor and sensory input to the pelvic floor muscles, which help to maintain continence. Bowel incontinence associated with an increased likelihood that patients will be placed in nursing homes.16,17 This study confirms a similar likelihood for TBI, both at rehabilitation discharge and 1-year postinjury. Again this relationship may reflect the notion that bowel incontinence is a marker for greater injury severity, but there may also be a direct causal relation. Bowel incontinence results in significant physical requirements of patients and caretakers, often necessitating full-time care and preventing involvement in community activities. This heavy family burden, plus the patient’s difficulty in resuming preinjury lifestyle, may necessitate placement in an institution. Given this type of burden, persistent incontinence may be among the consequences of injury severity that lead to increased acute rehabilitation LOS. Moreover, if bowel incontinence is not resolved sufficiently, it may be a main factor in discharging a patient to an institution, as opposed to a home. In fact, landmark research by Granger et al17 found bowel incontinence to be the strongest predictor of nursing home placement after stroke. CONCLUSION Bowel incontinence after TBI is a significant functional deficit, affecting both day-to-day care needs and the ability of an individual to return home. No published research exists that clearly identifies the incidence and degree of bowel incontinence in the TBI population. Despite the obvious importance of this information and the relative ease with which it can be acquired, the limited research into this critical function may reflect the discomfort felt by patients, families, clinicians, and researchers with an open discussion of bowel care and regulation. This study is the first comprehensive analysis of the incidence of bowel incontinence and associated factors in a large multicenter population after TBI. The inability of retrograde analyses to differentiate between individuals who would eventually be bowel incontinent versus continent necessitates early and aggressive management of bowel regulation after TBI. Although several factors in this study are associated with a greater likelihood of incontinence in the first year after injury, it is clear that none provides consis-

FECAL INCONTINENCE AFTER TBI, Foxx-Orenstein

tent evidence of concomitant bowel incontinence. This may reflect the multifactorial nature of continence, as well as the interrelationship of the numerous demographic, injury severity, and functional outcome factors after TBI. Further analysis, using well-controlled, prospective methodology with specific focus on standardizing bowel-management protocols and regulating secondary factors that may influence incontinence, is encouraged. References 1. Toglia MR. Pathophysiology of anorectal dysfunction. Obstet Gynecol Clin North Am 1998;25:771-81. 2. Haugen V, Moore A. “I will manage”: promoting continence through community education. J Wound Ostomy Continence Nurs 1995;22:291-5. 3. Gibson E. An exhibition to eradicate ignorance. Setting up a continence resource center. Prof Nurse 1990;6:38-41. 4. Francombe J, Carter PS, Hershman MJ. The aetiology and epidemiology of fecal incontinence. Hosp Med 2001;62:529-32. 5. Faltin DL, Sangalli MR, Curtin F, Morabia A, Weil A. Prevalence of anal incontinence and other anorectal symptoms in women. Int Urogynecol J Pelvic Floor Dysfunct 2001;12:117-20. 6. Jacquot JM, Finiels H, Fardjad S, Belhassen S, Leroux JL, Pelissier J. Neurological complications in insufficiency of the sacrum. Three case reports. Rev Rhum Engl Ed 1999;66:109-14. 7. Harrison-Felix C, Newton N, Hall K, Kreutzer J. Descriptive findings from the Traumatic Brain Injury Model Systems National Database. J Head Trauma Rehabil 1996;11(5):1-14.

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8. Guide for the Uniform Data Set for Medical Rehabilitation, version 5.0. Buffalo (NY): State Univ New York; 1996. 9. Forer S. Functional assessment instruments in medical rehabilitation. J Organization Rehabil Evaluators 1982;2:29-41. 10. Granger CV, Hamilton BB, Keith RA, Zielesny M, Sherwin FS. Advances in functional assessment for medical rehabilitation. Top Geriatr Rehabil 1986;1:59-74. 11. Hall KM, Johnston MV. Outcomes evaluation in traumatic brain injury rehabilitation. Part II: Measurement tools for a nationwide data system. Arch Phys Med Rehabil 1994;75:SC10-8. 12. Choi SC, Ward JD, Becker DP. Chart for outcome prediction in severe head injury. J Neurosurg 1983;59:294-7. 13. Cifu DX, Kreutzer JS, Marwitz JH, Rosenthal M, Englander J. Medical and functional characteristics of older adults with traumatic brain injury: a multicenter analysis. Arch Phys Med Rehabil 1996;77:883-8. 14. Hagen C. Language cognitive disorganization following closed head injury: a conceptualization. In: Trexler LE, editor. Cognitive rehabilitation: conceptualization and intervention. New York: Plenum Pr; 1982. p 131-51. 15. Malkmus D. Cognitive assessment and goal setting. In: Rehabilitation of the head injured adult: comprehensive management. Downey (CA): Rancho Los Amigos Hospital; 1979. 16. Cifu DX, Lorish T. Stroke rehabilitation: outcome. Arch Phys Med Rehabil 1994;75:S56-7. 17. Granger CV, Hamilton BB, Gresham GE, Kramer AA. The stroke outcome study. Part 2. Relative merits of the total Barthel Index score and a four-item subscore in predicting patient outcomes. Arch Phys Med Rehabil 1989;70:100-3.

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