SUBSTANCE ABUSE DISORDERS continue to be a major. The Magnitude and Correlates of Alcohol and Drug Use Before Traumatic Brain Injury

1765 The Magnitude and Correlates of Alcohol and Drug Use Before Traumatic Brain Injury Charles H. Bombardier, PhD, Carl T. Rimmele, PhD, Heather Zintel, BA ABSTRACT. Bombardier CH, Rimmele CT, Zintel H. The magnitude and correlates of alcohol and drug use before traumatic brain injury. Arch Phys Med Rehabil 2002;83:1765-73. Objective: To describe preinjury alcohol and drug use and opportunities for secondary prevention among persons with recent traumatic brain injury (TBI). Design: Survey. Setting: Acute inpatient rehabilitation program. Participants: A total of 142 (91%) of 156 consecutive admissions who met inclusion criteria and were screened. Interventions: Not applicable. Main Outcome Measures: Alcohol and drug use questionnaires, alcohol problem questions, toxicology results, readiness to change, and treatment preference questions. Results: Subjects were on average 37 years old, 80% were men, and 80% were white. Fifty-nine percent of the sample was considered at-risk drinkers and, as a group, subjects reported a high degree of preinjury alcohol-related problems. Thirtyfour percent reported recent illicit drug use, and 42 (37%) of 114 cases with toxicology results were positive for illicit drugs. Motivation to change alcohol use correlated positively with greater self-reported alcohol consumption and problem severity. Most at-risk drinkers wanted to change on their own, whereas a minority were interested in treatment or Alcoholics Anonymous. Conclusion: Both alcohol abuse and drug use are common before TBI. Inpatient brain injury rehabilitation represents an important opportunity to identify and intervene in substance abuse problems. Key Words: Brain injuries; Rehabilitation; Substance-related disorders. 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation SUBSTANCE ABUSE DISORDERS continue to be a major comorbid condition among persons with traumatic brain injury (TBI). Corrigan 1 published the most thorough examination of this somewhat piecemeal literature on rates of substance abuse among persons with TBI and concluded that one third to From the Department of Rehabilitation Medicine, University of Washington School of Medicine (Bombardier, Zintel); and the Department of Psychiatry and Behavioral Sciences and Seattle Veterans Administration Medical Center (Rimmele), Seattle, WA. Supported by the National Center for Injury Prevention and Control and the Disabilities Prevention Program, National Center for Environmental Health (grant no. R49/CCR011714-01). The contents of this article are solely the responsibility of the authors and do not necessarily represent the official views of the National Center of Injury Prevention and Control. 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. Correspondence to Charles Bombardier, PhD, Dept of Rehabilitation Medicine, Box 359740, Harborview Medical Ctr, 325 9th Ave, Seattle, WA 98104, e-mail: chb@u.washington.edu. Reprints are not available. 0003-9993/02/8312-6895$35.00/0 doi:10.1053/apmr.2002.36085 one half of persons hospitalized for TBI were intoxicated at the time of injury and that 50% to 66% also had a history of alcohol or other drug abuse. However, he noted that the literature in this area and the conclusions that could be drawn from it were limited by a number of methodologic weaknesses among existing studies. Few studies at the time of his review had been conducted on rehabilitation patients. There were few studies on unselected consecutive samples and fewer still with prospective designs. Only 3 studies 2-4 examined consecutive patients with TBI admitted to rehabilitation units. Two of these studies 3,4 used retrospective designs, and the single prospective study 2 used a clinical interview to document rates of drug and alcohol abuse. None of the rehabilitation studies collected both self-report and toxicology data to document alcohol use or abuse. Three studies 2,5,6 collected data on preinjury drug use, but there was a complete absence of data on the use of other drugs at the time of injury. Since Corrigan s review, the literature has been advanced by at least 3 major studies. Hibbard et al 7 used the Structured Clinical Interview, from the Diagnostic and Statistical Manual of Mental Disorders, 4th edition 8 (DSM-IV), to assess axis I psychiatric disorders in 100 community-residing persons with TBI. In the retrospective arm of their study, 40% of the sample met DSM-IV criteria for substance abuse or dependence before injury. Their study 7 showed that substance abuse was the most common preinjury psychiatric disorder among persons with TBI and the second most common disorder (28%) an average of almost 7 years after injury. In the second study, 9 a consecutive series of 197 hospitalized survivors of TBI were observed prospectively for 1 year. Alcohol use and associated problems were shown to decrease after TBI, but both were on the rise again by 1 year after injury. Alcohol consumption did not reach preinjury levels by 1 year after injury. More severe TBI (based on Glasgow Coma Scale [GCS] scores), higher blood alcohol level (BAL) measured in the emergency department, and older age (21 30y vs 15 20y) predicted greater decreases in drinking parameters. In the third study, 10 cross-sectional (n 322) and longitudinal (n 73) data were obtained on persons 1 to 4 years after TBI. The data showed that the proportion of moderate to heavy drinkers (22% 29%) was generally comparable to that of the general population. Abstinence rates were higher than in the general population; however, drinking rates varied over time, with a general trend toward increasing consumption. Taken together, these studies suggest that TBI reduces, but does not cure, preinjury alcohol problems. Although a large percentage abstain from alcohol after TBI, a substantial minority of persons are moderate to heavy drinkers. Moreover, there seems to be a trend toward increasing use over time. Despite these data, few rehabilitation centers have systematic screening, assessment, or treatment programs, and few viable treatment programs are even described in the literature. 1,11,12 Apparently, more needs to be done to document the magnitude and clinical significance of substance abuse problems in this population. This article will attempt to fill in some of these voids. First, we gathered information on preinjury alcohol use because smaller sample sizes and

1766 ALCOHOL AND DRUG USE, Bombardier Sample Characteristics Table 1: Demographic Characteristics for Total Sample and Subsamples Total Sample (n 142) At-Risk Drinkers (n 85) Not At Risk (n 57) Mean age SD (y) 37.4 12.6 36.5 11.0 38.7 14.8 NS Gender, n (%).001 Men 116 (81.7) 77 (66.4) 39 (33.6) Women 26 (18.3) 8 (30.8) 18 (69.2) Race, n (%) NA* White 114 (80.3) 67 (58.8) 47 (41.2) Black 14 (9.9) 7 (50.0) 7 (50.0) Native American 6 (4.2) 6 (100.0) 0 Hispanic 5 (3.5) 5 (100.0) 0 Asian American 3 (2.1) 0 3 (100.0) Marital status, n (%).000 Single 71 (50.0) 49 (70.0) 21 (30.0) Married/cohabiting 41 (29.6) 15 (35.7) 27 (64.3) Separated/divorced 25 (17.6) 19 (76.0) 6 (24.0) Employment status, n (%) NS Full-time 82 (59.0) 48 (58.5) 34 (41.5) Part-time 18 (12.9) 13 (72.2) 5 (27.8) Unemployed 22 (15.8) 16 (72.7) 6 (27.3) Education, n (%).011 Less than high school 33 (23.4) 23 (69.7) 10 (30.3) High school 57 (40.4) 39 (68.4) 18 (31.6) More than high school 51 (37.2) 22 (43.1) 29 (56.9) Abbreviations: NA, not available; NS, not significant; SD, standard deviation. * This relationship could not be assessed statistically due to the high proportion of small or empty cells. P nonconsecutive sampling have limited prior studies in rehabilitation populations. 1 There has been speculation that rates of alcohol abuse among patients with TBI sampled from rehabilitation units might actually be higher than among those hospitalized on general hospital wards. 1 Our setting permits us to compare the rates of alcohol problems among rehabilitation patients with TBI and among patients admitted for trauma generally. 13 Next, we collected data on selfreported use of other drugs and toxicology results because there are limited data on types and rates of drug use among persons with TBI. Moreover, the combination of alcohol and drug use may alter treatment planning and prognosis. 14 Finally, we wanted to provide data on patient variables that might be of use in judging prognosis and matching patients to treatment. Our intention to gather information on prognosis and treatment matching is consistent with the recommendations in the recently published National Institutes of Health Consensus Conference on Traumatic Brain Injury. 15 The panel made several recommendations that were directly or indirectly relevant to substance abuse. The conferees concluded that substance abuse evaluation and treatment should be a component of rehabilitation programs. 15(p980) This recommendation not only begins to recognize the prevalence of these problems, but is also consistent with national trends toward integrating substance abuse services into other health care settings. 16 The conference also articulated 2 other conclusions that are as relevant to substance abuse issues as they are to rehabilitation in general. They wrote, Rehabilitation services should be matched to the needs, strengths and competencies of each person and Persons with TBI and their families should play a central role in the development of individual rehabilitation programs and research endeavors. 15(p980) Toward this end, the goals of this study included describing the perceived needs and preferences of persons with alcohol problems. We asked patients whether they were interested in formal substance abuse treatment, attending Alcoholics Anonymous (AA), or changing their drinking on their own. We also asked patients questions regarding problem recognition, interest in making behavioral changes, or denial of alcohol-related problems. We predicted that findings from this consecutive sample would replicate previous research showing that patients with greater indications of alcohol problems report greater readiness to change their alcohol use. We used these data to emphasize the opportunity for substance abuse problems to be identified and addressed in the context of brain injury rehabilitation. METHOD Participants Subjects were drawn from 203 consecutive inpatients with recent TBI. One hundred fifty-six persons met our inclusion criteria. Forty-seven were excluded for the following reasons: too cognitively impaired (n 18), non English speaking (n 15), severe psychiatric disorder (n 6), younger than 18 years of age (n 3), not the initial rehabilitation admission (n 3), and discharged to homeless shelter or to prison (n 2). Of the 156 persons who met inclusion criteria, 144 (92%) were successfully screened, whereas 11 were discharged before screening and 1 person refused. Two more subjects were excluded due to unreliable responding, leaving a final sample of 142 persons. As can be seen in table 1, the final sample of subjects was on average 37.4 years old (median, 37y), approximately 80% were white, and 80% were men. More than two thirds of subjects were single, divorced, or separated; 72% worked full- or parttime; and 78% had at least a high school education.

ALCOHOL AND DRUG USE, Bombardier 1767 Procedures Patients were administered the questionnaires by a trained interviewer as a part of standard rehabilitation care. Measures were administered an average of 27.1 days after TBI (median, 29d) and 7.7 days after admission to the rehabilitation unit. To prevent potential reactivity effects of the alcoholism measure on the measures of readiness to change, the readiness to change instrument was always administered first. In addition, there were no systematic attempts to educate patients about or to intervene in alcohol-related problems before the study assessment. Relevant medical diagnostic and clinical information was obtained from the patient s chart. Our human subjects institutional review board approved all procedures for this study. To enhance participation and subject protection, we obtained a Certificate of Confidentiality from the National Institute on Alcoholism and Alcohol Abuse (NIAAA). This certificate affords investigators the right to refuse disclosure of any alcohol-related research information, even under subpoena, to local, state, or federal authorities. Measures Alcohol consumption and drug use. Drinking was assessed by asking how many times per month subjects drank any alcoholic beverage before injury, as well as how many drinks they typically consumed on each drinking occasion. Binge drinking was assessed by asking the number of times in the past month the patient had consumed 5 drinks on a single occasion. Subjects also were asked whether they had driven an automobile in the past month after having consumed 2 drinks. Finally, subjects were asked what illicit drugs they had used any time during the 3-month period before injury. Physical dependency. The Ph scale from the Brief Drinkers Profile 17 was administered as a measure of physical dependency on alcohol. Items included Are you always able to stop drinking when you want to? and Are you able to drink more now than you used to without feeling the same effect? Alcohol dependence scores on this scale range from 0 to 20, with the following qualitative ranges suggested by the authors: 1 to 4 (mild), 5 to 10 (definite and significant), 11 to 14 (substantial), and 15 to 20 (severe). Lifetime alcohol-related problems. The Short Michigan Alcoholism Screening Test 18 (SMAST) is a 13-item list of common signs and symptoms of alcoholism. The subjects indicate whether they have ever experienced each symptom of problem drinking during their lifetime. Examples of items include Does any member of your family (eg, wife, husband, parents) ever worry or complain about your drinking? and Have you ever gotten into trouble at work because of drinking? Item scores are equally weighted and summed to form a total score. The SMAST is used because it is brief and has shown reliability and validity in a number of populations. 19 The traditional cutoff of 3 was used to indicate a clinically significant history of alcohol problems. 19 Readiness to change. The Readiness to Change (RTC) Questionnaire was used to assess readiness to change preinjury drinking patterns. It is composed of statements reflecting thoughts and behaviors associated with the most common stages of change found among persons in health care settings (ie, precontemplation, contemplation, action) and was specifically developed for brief opportunistic assessments in medical settings. 20,21 Precontemplation items refer to the denial or nonendorsement of alcohol-related problems. Contemplation items refer to beliefs that alcohol may be a problem. Action items reflect behavior changes the person is already making to cut down or stop drinking. Participants rate the degree to which they agree or disagree with each item on a 5-point Likert-type scale. The RTC has shown reliability and validity and has been used to assess readiness to change drinking habits in acutely hospitalized patients with TBI and spinal cord injury. 22,23 For the heuristic value of stage assignment and for comparability to other studies, the original 12-item version of this measure was used to categorize each at-risk drinker into a specific stage of change. However, for other descriptive and correlational analyses, a revised version of the RTC was used. The RTC was reanalyzed to create a single continuous measure of readiness to change in people with TBI. 24 This rating scale analysis showed 2 misfitting items that were subsequently dropped. The remaining 10 items were rescored and rescaled to produce an interval level continuous measure of readiness to change. Preferred change strategies. Subjects were asked, At the present time are you interested in: Alcohol treatment? Trying AA? Making changes on your own? Subjects were asked to indicate yes or no for each change strategy. Blood alcohol and toxicology testing. Serum BAL (mg/ dl) and toxicology screens are measured as a routine part of the emergency room assessment of trauma patients in our medical center. In this sample, 130 (91.5%) cases had a BAL report, which we obtained from the medical record. For toxicology screens, 114 (80.2%) cases had results reported in the medical record. Attributions regarding the cause of injury. Subjects were asked to indicate the degree to which they thought they were responsible for the cause of their injury. Similarly, they were asked about the extent to which they thought alcohol or drug use was a cause of their injury. Ratings for both questions were made on a 0- to 2-point ordinal scale (not at all, somewhat, very much). RESULTS Definition of At-Risk Drinkers This research is part of an ongoing treatment study. The treatment study has specific inclusion criteria that were devised to identify persons whose preinjury drinking pattern might place them at risk for alcohol-related problems generally. 25 The inclusion criteria were as follows: (1) being a current drinker and scoring in the alcoholic range on the SMAST; (2) being intoxicated at the time of admission to the emergency room (BAL, 99mg/dL); or (3) having a recent history of risky drinking, including binge drinking ( 5 drinks per occasion), more than once in the month before injury or driving an automobile after having had 2 drinks at least once in the month before injury. On the basis of the previously mentioned criteria, 85 persons (59%) were classified as at-risk drinkers. Sixty-three persons (74.1%) met at-risk criteria on the basis of their SMAST score. Fourteen persons (16.5%) had normal SMAST scores, but were intoxicated at the time of their injury. Eight persons (9.4%) were considered at-risk drinkers on the basis of other recent risky drinking behaviors, such as binge drinking (n 4) or driving after having 2 drinks (n 4). Of the 57 persons not considered to be at risk, 5 (8.8%) were abstinent alcoholics. That is, they reported a significant history of alcohol problems on the SMAST but reported having abstained from alcohol for longer than 1 year at the time of injury. If one combines persons with past or present alcohol abuse, the total proportion of persons with a lifetime history of at-risk drinking was 64.7%.

1768 ALCOHOL AND DRUG USE, Bombardier Table 2: Drinking and Drinking Problems in the Total Sample and At-Risk Drinkers Drinking Characteristics Total Sample At-Risk Drinker BAL on admission (mg/dl) n 130 n 80 0 75 (57.7%) 27 (33.8%) 23 99 13 (10.0%) 11 (13.7%) 100 199 19 (14.6%) 19 (23.8%) 200 299 16 (12.3%) 16 (20.0%) 300 352 7 (5.4%) 7 (8.7%) Lifetime alcohol-related problems (SMAST) n 142 n 85 SMAST positive ( 3) 70 (49.3%) 63 (74.1%) Have attended AA 65 (45.8%) 54 (63.5%) Have gone for help about drinking 35 (24.6%) 32 (37.6%) Have been arrested for driving while intoxicated 44 (31.0%) 39 (45.9%) Have been arrested for other drunk behavior 27 (19.0%) 24 (28.2%) Preinjury alcohol use patterns n 137 n 82 Mean no. of drinking occasions per month SD 8.1 9.6 11.5 9.7 Mean no. of drinks consumed per occasion SD 3.7 4.2 5.6 4.5 Average no. of drinks per week SD 11.2 21.6 18.0 25.9 Drove after having 2 drinks 29 (20.4%) 29 (34.5%) Binge drinking ( 5 drinks per occasion) at least once 65 (47.4%) 60 (72.0%) Physical dependency n 142 n 85 None (0) 21 (14.8%) 2 (2.4%) Mild (1 4) 73 (51.1%) 41 (48.2%) Significant (5 10) 33 (23.1%) 27 (31.8%) Substantial (11 14) 13 (9.1%) 13 (15.3%) Severe (15 20) 2 (1.4%) 2 (2.4%) Demographics and At-Risk Status As can be seen in table 1, at-risk status is associated with some demographic factors. A significantly higher proportion of at-risk persons was found among men; persons who were single, separated, or divorced (vs married persons); and persons with less than a high school education. Due to the small number of subjects from minority ethnic backgrounds, the relationship between at-risk status and ethnicity could not be evaluated statistically. However, it is notable that no one from an Asian background met criteria for at-risk drinking, whereas 100% of the Native Americans and Hispanic persons were included in the at-risk category. Blood Alcohol Level BALs obtained on admission were available for 130 (92%) cases (table 2). Of these, 55 (42.3%) had a positive BAL and 42 (32.3%) were intoxicated (at or above the legal limit of 100mg/ dl). Higher BAL was associated with lower GCS scores at the time of admission (Spearman.32) but was not related to gender, age, or education. Of those who were intoxicated, 64.8% also scored in the alcoholic range on the SMAST, suggesting that they also had a history of more chronic alcohol problems. Of those who were not intoxicated, 36.8% scored in the alcoholic range on the SMAST. Alcohol Use Patterns One hundred nine persons (76.8%) reported drinking at least once in the month before injury. Fifteen persons reported having no alcohol for at least 1 year. On the basis of the total sample, subjects drank on average 8.1 9.6 times per month and 3.7 4.2 drinks per occasion. The average number of drinks per week (11.2) is at the 75th percentile for American males and in the 84th percentile overall. 26 Nearly half (47.4%) of the total sample reported binge drinking, and one fifth drove an automobile after having 2 drinks in the month before TBI. As a group, single, divorced, or separated persons drank more than married and cohabiting persons (13.3 vs 6.3 drinks per week, P.001). Weekly consumption did not vary, however, by gender or employment status. Drinks per week also was unrelated to age and years of education. Preinjury Alcohol-Related Problems As can be seen in table 2, the rates of self-reported alcohol problems in this population are quite high. Overall, nearly 50% of the total sample scored above the cutoff of 3 or more on the SMAST. Some of the most commonly endorsed SMAST items were: having attended 1 or more AA meetings (45.8%), having been arrested for driving while intoxicated (31%), having gone for help about drinking (24.6%), and having been arrested for other behavior associated with intoxication (19%). Drug Use Self-report data on drug use were obtained on 137 persons (96% of the sample) (table 3). Overall, 43 (31.4% of the sample) admitted using 1 illicit drugs, primarily marijuana, cocaine, and amphetamines, during the 3 months before injury. Cocaine and marijuana use was significantly more common among at-risk drinkers, whereas amphetamine and other drug use did not vary by drinking category. Eighty percent of the sample (n 114) had a toxicology screen performed, with 43 (37.7%) of the tested sample being positive for marijuana, cocaine, or amphetamines on admission (see table 3). Cocaine use was significantly higher among at-risk drinkers (odds ratio 6.1), whereas marijuana and amphetamine use was roughly equivalent among at-risk and notat-risk drinkers. The toxicology screens also included opiates and benzodiazepines, which were positive in 33.3% and 21.1% of all screened cases, respectively. However, it was impossible to determine exactly what proportion of the time these drugs were administered for therapeutic reasons by emergency med-

ALCOHOL AND DRUG USE, Bombardier 1769 Table 3: Rates of Self-Reported Drug Use and Admission Toxicology Results for the Total Sample and by At-Risk Drinking Source of Data Total Sample (n 137) At-Risk Drinkers (n 82) Not At-Risk Drinkers (n 55) OR (95% CI) Self-reported drug use Cocaine 14 (10.2%) 12 (14.6%) 2 (3.6%) 4.5 (0.9 21.2)* Marijuana 35 (25.5%) 28 (34.1%) 7 (12.7%) 3.6 (1.4 8.9) Amphetamines 10 (7.3%) 7 (8.5%) 3 (5.5%) 1.6 (0.4 10.9) Hallucinogens 2 (1.5%) 1 (1.2%) 1 (1.8%) 0.7 (0.4 10.9) Heroin 3 (2.2%) 3 (3.7%) 0 1.0 (1.0 1.0) Other 1 (0.7%) 1 (1.8%) 0 0.6 (0.5 0.7) No. of self-reported users 43 (31.4%) 34 (41.5%) 9 (16.4%) 3.6 (1.6 8.4) (n 114) (n 64) (n 50) Positive toxicology results Cocaine 15 (13.2) 13 (20.3%) 2 (4.0%) 6.1 (1.3 28.5)* Marijuana 27 (23.7) 19 (29.7%) 7 (14.0%) 2.2 (0.9 5.6) Amphetamine 10 (8.8) 5 (7.8%) 5 (10.0%) 0.8 (0.2 2.8) No. with positive screen 43 (37.7%) 32 (50.0%) 11 (22%) 3.5 (1.5 8.1) Abbreviations: CI, confidence interval; OR, odds ratio. * Significant association with at-risk drinking, P.05 (Pearson chi-square); P.01 (Pearson chi-square). ical technicians or staff from other hospitals. Therefore, these data were not analyzed further. Drug use screening by these 2 methods has notable similarities and differences. The same total number of drug users was identified by each method. However, a higher proportion of those on whom toxicology data were obtained was positive for illicit drug use compared with the proportion of positive screens for persons on whom self-report data were gathered. Conversely, a higher proportion of patients could be screened by self-report methods than by toxicology. Combining toxicology and self-report measures to identify drug users shows that 57 (40.1%) of the total sample either reported illicit drug use within the past 3 months or tested positive for some illicit drug. As implied previously, the agreement between these 2 indicators of drug usage is not perfect. The overall degree of agreement was moderate (.59). Of the 112 cases with both toxicology and self-reported data on drug use, there was agreement between the 2 methods in 91 (81.3%) of all cases. Of 76 people, 14 (18.4%) denied drug use but tested positive for 1 illicit drugs, whereas 7 persons admitted using drugs during the 3 months before injury but tested negative for drugs at the time of injury. Similarly, agreement between toxicology and selfreport within specific types of drugs was only fair ( range,.37.64). For example, toxicology and self-reported cocaine use indicators were both positive in only 6 cases. In 9 cases, the patients denied cocaine use, but their toxicology screens were positive for cocaine. In 6 cases, the patients admitted using cocaine in the past 3 months but did not test positive for cocaine at the time of injury. Similar issues with estimating drug use from only 1 parameter were noted with marijuana and amphetamines. Combined Alcohol and Drug Use Categories In figure 1, we summarize alcohol and drug use for the entire sample. Examining drug and alcohol use together shows several interesting facts. Of the 5 persons with a history of alcoholism who reported abstaining from alcohol for at least 1 year, 2 had positive toxicology screens for other illicit drugs. Therefore, there seemed to be only 3 persons in this subsample who were truly abstinent from alcohol and drugs. Next, although drug use was common, only 4 persons used drugs but not alcohol. Only 9 persons (6%) reported complete abstinence from alcohol for at least 1 year as well as no use of drugs for at least 3 months before injury. Of the 50 persons (37%) of the sample who used both alcohol and drugs, 70% had a history of significant alcohol-related problems on the SMAST. Finally, only 21% of the sample used alcohol safely, did not use drugs, and did not have a history of significant alcohol-related problems. Fig 1. Drinking and drug use categories for those subjects with or without lifetime alcohol-related problems (n 142). NOTE: White areas represent persons without significant lifetime alcohol-related problems (SMAST score <3). Within the white areas: No alcohol or drug use, no alcohol use within past year, no drug use; Normal alcohol use, alcohol use without repeated binge drinking, drinking and driving, or drug use; Risky alcohol use, self-reported binge drinking (>2) or driving after drinking, but no drug use; Drug use, drug use with no alcohol use in at least 1 year; Alcohol and drug, current alcohol and drug use. Shaded areas represent persons with significant lifetime alcohol-related impairments (SMAST score >3). Within the shaded areas: Alcohol and drug, current alcohol and drug use; Alcohol use, current alcohol use without current drug use; Alcoholism in recovery, no alcohol use within past year and no drug use; Abstinent alcoholic with current drug use, no alcohol use within past year, but current drug use.

1770 ALCOHOL AND DRUG USE, Bombardier Table 4: Stage of Change and Interest in Common Change Strategies Among At-Risk Drinkers Variable n (%) Proportion in each (highest) stage of change (n 84)* Precontemplation 19 (22.6) Contemplation 27 (32.1) Action 38 (45.2) Preferred change strategies (n 76) Want treatment 13 (17.1) Wanting to try AA 15 (19.7) Wanting to make changes on their own 53 (69.7) * One subject obtained equal scores on all 3 subscales and could not be assigned to a specific stage. Nine subjects (10%) did not answer these questions. Motivation to Change Alcohol Use On the basis of the original scoring of the RTC Questionnaire, we categorized all at-risk drinkers into 1 of 3 mutually exclusive stages of change. Nineteen (23%) were in the precontemplation phase, 27 (32%) were in the contemplation phase, and 39 (45%) were in the action phase (table 4). Although the largest fraction of the sample reported that they were currently making concrete changes in their drinking, almost a quarter reported that they did not drink too much or that they saw no need to change their alcohol consumption. Almost a third reported that they were only thinking about change. With the revised RTC, mean readiness to change was 17.3 5.1, and the 25th and 75th percentile scores were 14 and 20, respectively. We attempted to replicate previous findings that related alcohol problem severity to readiness to change. 23 To do this, we examined Pearson correlations between the revised RTC variable and alcohol problem indicators among at-risk drinkers. Greater readiness to change correlated positively with higher SMAST scores (r.39, P.01), higher levels of physical dependency (r.31, P.01), and total number of drinks per week (r.30, P.01), but not admission BAL (r.14). We were interested in the relationship of alcohol as a cause of injury to subsequent readiness to change. Because BAL is an imperfect indication of possible alcohol involvement in the person s injury, subjects were asked to rate the degree to which they thought they were responsible for their injury and the extent to which they thought alcohol or drugs were a cause of their injury. These ratings were correlated with revised readiness to change scores among at-risk drinkers. Attributing the cause of injury to oneself did not correlate significantly with readiness to change (Spearman.15). Attributing the cause of injury to alcohol or drugs, however, was correlated weakly with greater readiness to change (.27, P.02). Preferred Change Strategies Finally, we wanted to describe the sample in terms of what change strategies would be acceptable to at-risk drinkers. Data about treatment preferences were available on 77 (90.5%) of the at-risk drinkers. Fifteen percent reported wanting alcohol treatment, 17.6% wanted to attend AA, and 63.5% reported wanting to change their alcohol use on their own. Ten persons (13%) were interested in all 3 options. Fifty-five (71.4%) of at-risk drinkers endorsed interest in at least 1 of the 3 change strategies, leaving 22 (28.6%) who were interested in none. Those who wanted to try AA, treatment, or self-change all reported significantly more alcohol-related negative consequences over their lifetime (SMAST), greater physical dependency, and greater readiness to change (all P.05). People who wanted to change on their own reported significantly higher weekly alcohol consumption than those not wanting selfchange (P.001), but the same was not true of people wanting to attend AA or treatment (all P.10). By chi-square tests, persons who had attended AA in the past were more likely to want treatment, to attend AA, or to change on their own versus people who had never attended AA (all P.05). In fact, 45% of those who had ever attended AA in the past were interested in attending in the future, whereas not 1 person of those who had never attended an AA meeting was interested in attending AA in the future (P.05). A greater proportion of single, divorced, or separated persons (vs married or cohabiting) reported wanting to change on their own (P.01). Preferred change strategies were generally unrelated to age, years of education, employment status, and BAL. DISCUSSION The results of the present study are consistent with previous research on people who sustained TBI as well as on trauma survivors more generally. Both groups have high rates of alcohol use and alcohol-related problems before injury. In our sample, approximately one third were intoxicated at the time of injury. This rate of intoxication is slightly below the range reported in other studies of persons with TBI, that is, 36% to 51%. 1 Alternatively, it is quite similar to the rate of intoxication (36%) found in a sample of 2657 general trauma patients who were admitted to our institution nearly 10 years ago. 13 Potential reasons for the discrepancy between our data and previous TBI-related research include decreases in heavy drinking that have occurred throughout the United States 27 or perhaps the cumulative effects of drinking and driving prevention and law enforcement efforts. Because selective BAL measurements in emergency departments are likely to be biased toward persons who are intoxicated, obtaining toxicology and screening data on a high proportion of consecutive subjects, as we did, may also account for a lower rate of persons intoxicated. 28 The present study confirms previous findings that approximately half of all persons undergoing inpatient rehabilitation for TBI report a history of significant alcohol-related problems. The rate of significant self-reported alcohol-related problems on the SMAST (49%) is similar to what has been found among general trauma patients at our institution (44%), with the same measure. 13 In contrast, rates of lifetime alcohol-related problems reported by persons with TBI were much higher than rates found among community-residing men. The SMAST was administered to a community sample of 620 men in a small Midwestern town. 29 In the community sample, only 16% scored above 2 on the SMAST, compared with 49% in our sample. Individual items were endorsed from one third to one tenth as frequently in the community versus TBI sample. For example, only 4% had ever attended AA in the community versus 46% in our study. In the community sample, 7% had been arrested for driving while intoxicated versus 31% among patients with TBI. Three percent of community-residing men had gone for help for drinking, and 6% had been arrested for other behavior while intoxicated, whereas 25% of persons with TBI had gone for help and 19% had been arrested for other behavior while intoxicated. Although alcohol problems are common among persons who have sustained TBI, the modal rehabilitation patient with significant alcohol problems is not a stereotypical alcoholic. That is, they are not older men who drink every day, have a high physical dependence, and have many alcohol-related problems. In this sample, problem drinkers were characterized by episodic heavy drinking, mild alcohol-related impairment,

ALCOHOL AND DRUG USE, Bombardier 1771 and frequently engaging in high-risk behaviors such as drinking and driving. At-risk persons were more likely to be single, male, and have less than a high school education. We believe that the typical severity of alcohol problems and alcoholrelated dependence in this population is great enough to warrant intervention, but mild enough to justify alternative types of interventions. 16 We will expand on this point below. The present study also indicates high rates of concurrent drug use in this population. Forty percent of the sample had a positive toxicology screen for marijuana, cocaine, or amphetamines or reported using illicit drugs within 3 months of their injury. At-risk drinkers were more likely than those not at risk to report concurrent use of marijuana or cocaine. Marijuana use accounted for more than half of the drug use; however, cocaine and amphetamine use was evident in 17% to 22% of the sample. Drug use without the use of alcohol was relatively rare, occurring in only 2% of the sample. There were discrepancies between self-report and toxicology screens for drug use. Some subjects may have lied about their drug use, but memory impairment, especially retrograde amnesia, may also account for some of the cases in which subjects denied drug use in the context of having a positive toxicology screen. Furthermore, like any other test, toxicology assays can also produce false-positive results. In cases in which self-report detected drug users with negative toxicology screens, discrepancies are largely attributable to the fact that self-report questions inquired about drug use within the period of 3 months before injury, whereas detection of drug use via serum toxicology can be limited to a period of hours or days. Although there was imperfect agreement between these 2 screening methods, asking a simple drug use question seems to have much to recommend it. This question was answered by more than 95% of the sample, it identified as many drug users as the toxicology method, and the false-positive rate was only 18% (although there were likely cases that went undetected by both methods). The sheer magnitude of the rates of alcohol and other drug problems underscore the importance of routinely screening patients for both. There are, however, several other reasons why rehabilitation programs should screen every patient for a history of substance abuse problems. First, evidence indicates that, in a variety of clinical settings, clinicians do not detect significant alcohol problems. 30 From our experience, drug use is probably even harder to detect without systematic screening. Next, knowing whether survivors of TBI have a history of alcohol abuse can help predict important outcomes such as neuropsychologic function 8 and community integration. 1 Similar evidence is accumulating that using drugs such as marijuana and cocaine also can cause residual neuropsychologic impairment. 31-33 Third, knowing who had problems with alcohol or drugs before injury can probably help predict who is at risk for substance abuse problems after TBI. 34 Finally, knowing when there is both drug and alcohol abuse allows the clinician to anticipate additional risks, such as dangerous synergistic effects with other drugs or medications, 35 higher relapse rates, 14 and more negative outcomes in terms of social instability, work-related problems, psychosocial impairment, and substance use severity. 36,37 Undertaking screening for substance abuse merits careful consideration. Some clinicians may be tempted to use BALs to detect persons at risk. Although BAL may be useful to identify some problem drinkers, our data and those of others suggest that BAL lacks the sensitivity to detect persons with significant alcohol problems. 13 We found that 34% of at-risk drinkers had a BAL of 0%, and 48% were below the level of legal intoxication. Self-report measures are the other alternative. One of the best self-report screening measures, the 10-item Alcohol Use Disorders Screening Test (AUDIT), combines information on alcohol use, alcohol-related problems, and symptoms of dependence into a single risk score. 38 The AUDIT has been shown to be among the most sensitive and specific screening measures in primary care medical populations. 39 Optimally, both biologic and self-report measures should be used to maximize screening effectiveness. These data reemphasize the opportunity for secondary prevention that exists during inpatient rehabilitation for TBI. More than 70% of at-risk drinkers reported wanting to attend AA, to enter treatment, or to change on their own. In the approximately 20% of cases in which patients indicate an interest in AA or treatment, the challenge for the clinician is to know the AA and treatment resources in the community, how to make an effective referral, and how to help substance abuse treatment providers make appropriate accommodations for persons with TBI. Although making treatment referrals can be fraught with problems, there is a growing literature on improving referral adherence for the interested reader. 38 For patients who want to attend AA, outcomes also may be improved through parallel counseling designed to help the individual effectively use the 12-step program. A detailed therapy manual has been written for this purpose and is available free of charge through the NIAAA web page (http://www.niaaa.nih.gov). Finally, the majority of those who want to change their drinking prefer to do so on their own. Clinicians who are steeped in disease model traditions or who have only worked with persons who have more severe alcoholism may have difficulty accepting self-change as a legitimate patient preference. We believe that the literature on the effects of physician advice 38 and on unassisted recovery from alcoholism 40,41 gives clinicians an empirical basis for viewing self-change as a viable option for many persons. Clinicians may want to use one of several self-help guides that are available 42,43 including one written specifically for persons with TBI. 44 In addition, an excellent resource for giving advice has been developed for primary care physicians and can be obtained from the NIAAA (http://www.niaaa.nih.gov/publications/physicn.htm). Before concluding, several limitations of this study must be acknowledged. First, the study was conducted at a single facility, and results may not generalize to other settings. Next, many of the data presented here are based on self-report. People may doubt the reliability of self-reports about alcoholrelated behavior generally and especially when elicited from people soon after TBI. However, reviews of the literature conclude that persons with alcohol problems generally provide reliable and valid reports if interviewed in clinical settings when they are alcohol free, approached in a nonjudgmental manner, and given reassurance of confidentiality. 45,46 Each of these conditions was met in this study. Regarding potential unreliability due to TBI, precautions were taken to exclude persons with communication impairments as assessed by the staff speech pathologists. We also attempted to compensate for inattention or poor memory by using an interview format and by presenting the materials in both oral and large-print written formats. Research comparing self-reported alcohol use with collateral reports of alcohol use among persons with TBI has shown excellent correspondence between the 2, 47 although future studies should include testretest data and provide corroborating information from family or friends. The present results are also limited by the lack of a standardized diagnostic test for alcoholism. Although the SMAST is a widely used screening tool and likely served as a useful indication of problem drinking behavior, it does not specifi-

1772 ALCOHOL AND DRUG USE, Bombardier cally diagnose alcohol dependence or abuse as defined in DSM-IV. Future researchers may want to use a diagnostic measure such as a DSM-IV based structured interview for determining rates of alcohol dependence or abuse. The data on patient readiness to change should be interpreted cautiously. Rather than a stable disposition, readiness to change is probably a fluid state. This is especially true for persons in contemplation, which is by definition a state of waffling between action and stasis. Moreover, therapist behavior is believed to influence motivation. The fact that our research personnel were trained to use the principles of motivational interviewing (empathy, nonjudgmental attitude, rolling with resistance) when screening patients may have influenced our measures of readiness to change. We placed the RTC measure early in the interview to reduce such potential effects. Also, there is evidence that the original scoring of the RTC measure is not optimal psychometrically. 24 Because stage assignment is not possible with the revised scoring method, we chose the original scoring procedures to assign individuals to specific stages for this study. Finally, the concept of low readiness to change, or precontemplation, deserves special scrutiny in this sample. Precontemplation typically refers to persons with definite drinking problems who are not aware of or deny their problems. In this study, at-risk drinkers were defined broadly, and the sample includes people who would likely not meet criteria for substance abuse or dependence. Therefore, some precontemplators or those with low revised RTC scores in this sample might argue that they do not have significant problems with alcohol and that, therefore, their low readiness to change is justified. CONCLUSION The results of the present study highlight the need for universal screening for drug and alcohol problems in acute rehabilitation settings. The data also describe the opportunity that exists for secondary prevention programs. Surgeons and other trauma specialists are recognizing the need to address the fact that alcoholism is the most common health problem among those who sustain trauma. 30 Rehabilitation professionals are enjoined to recognize this silent epidemic as well and to consider creative intervention models. More research is needed on the course and consequences of alcohol and drug use after TBI. Controlled studies are needed on how to prevent a return to alcohol and substance abuse after TBI, especially for those who report no interest in attending AA or formal treatment. Acknowledgments: We thank Kristin Knight, for her help with data collection, as well as Susan Pilcher and the Harborview Trauma Registry. References 1. Corrigan JD. 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