| | Perceived and Actual Memory, Concentration, and Attention Problems After Whiplash-Associated Disorders (Grades I and II): Prevalence and PredictorsAbstract Robinson JP, Burwinkle T, Turk DC. Perceived and actual memory, concentration, and attention problems after whiplash-associated disorders (grades I and II): prevalence and predictors. ObjectivesTo evaluate neuropsychologic test performance of people with whiplash-associated disorders (WADs) and to compare the performance of those who report cognitive symptoms (CS+) with those who do not (CS−). DesignCross-sectional analysis of a convenience sample. SettingOutpatient research center. ParticipantsPeople with recent WADs (N=203) who responded to advertisements to participate in a treatment study. InterventionsNot applicable. Main Outcome MeasuresParticipants completed a history form including information about demographics, medical history, description of the collision, litigation status, a set of instruments designed to assess neck disability, pain severity, depressed mood, pain-related anxiety, and fear of potentially stressful neck movements and completed a generic 38-item symptom checklist that included items about memory and concentration problems. They also were administered the third revision of the Wechsler Memory Scale (WMS-III) and the Trail-Making Test (TMT). Participants were designated CS+ if they endorsed memory problems or concentration problems on the symptom checklist and CS− if they did not endorse either type of problem. ResultsCS+ and CS− participants performed equally well on the TMT and on all WMS-III indexes. Univariate analyses revealed that CS+ participants scored higher than CS− participants in neck disability, pain severity, depression, pain-related anxiety, and fear of neck movements. They also endorsed more items on the symptom checklist, including items (eg, skin rash) that had no obvious connection with WADs. In a multivariate analysis, CS+ versus CS− status was predicted only by the total number of items endorsed on the symptom checklist. ConclusionsReports of memory or concentration problems appear to be indicators of heightened somatic vigilance rather than indicators of actual neuropsychologic deficits. Our results suggest that it is reasonable for physicians to defer neuropsychologic testing or advanced imaging studies on WAD patients who report cognitive symptoms but no other indicators of brain injuries and instead to rely on reassurance and education about the normal aftermath of motor vehicle collisions. THE QUEBEC TASK FORCE on Whiplash-Associated Disorders (WADs) created a useful grading system of WADs associated with motor vehicle collisions (MVCs).1 This system distinguishes among people with neck pain but no physical findings (grade I), pain and musculoskeletal findings such as reduced cervical range of motion (grade II), neurologic injury (grade III), and major skeletal injury such as a fracture (grade IV). The present study focuses on people with grades I and II WADs. They comprise more than 90% of all WADs sustained in MVCs.2 When people with WADs symptoms undergo medical evaluations, they routinely complete checklists that ask about a broad range of symptoms that they might be experiencing. The examining physician also typically asks for information about the nature and severity of the MVC and the patient’s symptoms after the MVC. The information that patients provide in response to these queries reflects their recollections about their MVC and its aftermath and their perceptions about their current functioning. The information may or may not be completely accurate, but it forms an important portion of the dataset, which the physician considers as he/she formulates a plan for managing a patient.3 Cognitive problems such as impaired memory or impaired ability to concentrate are among the symptoms frequently reported by people with WAD grade I or II injuries.4, 5 Physicians treating such patients must decide whether to refer the patients for neuropsychologic testing to document the presence and severity of deficits in cognitive functioning or for imaging studies that might identify brain lesions. The appropriateness of making such referrals depends on 2 issues: (1) Are the reports of cognitive problems valid, namely, do people who report them actually show deficits in cognitive functioning? and (2) If so, are these deficits indicators of traumatic brain injury (TBI) or other processes such as emotional distress or distraction secondary to pain? The present study addresses the first question because research to date has not provided a definite answer. There is some evidence that people with WADs show deficits on neuropsychologic tests of attentional processes and perhaps memory,6, 7, 8, 9, 10, 11, 12 although findings have not been entirely consistent.13 When neuropsychologic deficits are found, some investigators attribute them to subtle brain injuries.14, 15 However, the more widely held view is that people with WAD perform poorly because of emotional dysfunction and the distracting effects of pain.7, 10, 13, 16 WAD patients in neuropsychologic studies have generally been examined in the aggregate, with no attempt to distinguish between ones with cognitive symptoms compared with ones without them. We are aware of only 1 study in which such a distinction has been made. Di Stefano and Radanov4 compared WAD patients with persistent neck pain and cognitive symptoms to patients with persistent neck pain but no cognitive symptoms. The 2 groups performed comparably on multiple tests of memory; however, participants with cognitive symptoms performed somewhat worse than ones without such symptoms on 3 of 6 tests designed to assess attention and concentration. The present study compared people with WADs grades I and II who reported cognitive symptoms to ones who did not report such symptoms. The 2 groups were compared on well-established neuropsychologic tests of memory and concentration that have been used in several previous studies of WAD patients, the Trail-Making Test (TMT) and the Wechsler Memory Scale, third revision (WMS-III) (described later). Based on the available literature, we hypothesized that (1) people with WADs who report cognitive symptoms (CS+) will perform worse than those who do not report such symptoms (CS−) on attention-concentration tasks (TMT and working memory index of the WMS-III) but not on the other WMS-III indices, and (2) performance differences between CS+ and CS− will be eliminated when statistical controls for depressed mood and pain intensity are introduced. Methods  Participants A convenience sample of people with a history of a WAD from an MVC (N=203) were evaluated 2 to 3 months after their MVC in preparation for participation in a treatment trial for persistent neck pain. Inclusion criteria were as follows: (1) neck pain attributed to an MVC in the past 2 to 3 months, (2) not hospitalized after MVC, (3) no indication of loss of consciousness, (4) no current substance abuse, and (5) ability to understand and read English. All participants met the Quebec Task Force classification of WADs, grades I or II.1 Demographic information and collision-related characteristics are enumerated in table 1. The study was approved by the Biomedical Institutional Review Board at the University of Washington. | ⁎ Rating range: 5, some college; 6, college degree. †Rating range: 4, family income of $30,000–$40,000; 5, family income of $40,000–$50,000. ‡Rating range from 1 (minor) to 4 (extremely serious). §Rating range from 1 (< $500) to 4 (>$2500). ∥Taken from MPI (range, 0–6). |
Procedures The WAD grade of each participant was confirmed by a physical examination to rule out neurologic injury and by anteroposterior and lateral cervical spine radiographs to rule out fracture or dislocation. Participants completed a background and history form and several self-report questionnaires (described later). In addition, a licensed neuropsychologist administered the WMS-III and the TMT. Measures Background and history form The background and history form included demographic information (eg, age, ethnicity, income, education level), information about the MVC (eg, amount of damage to their vehicle), the types of treatments received (eg, use of centrally acting medications, including opioids, antidepressants, anticonvulsants, muscle relaxers), and legal consultation after the MVC (see table 1). Symptom checklist Participants completed a generic symptom checklist on which they indicated the presence of any of 38 symptoms (table 2) that they may have noticed after their MVC. The symptom checklist consisted of symptoms frequently associated with WADs (eg, pain, tingling, numbness) and symptoms believed not to be specifically related to WADs (eg, gastrointestinal problems, shortness of breath). Two items on the symptom checklist addressed cognitive symptoms; specifically, they asked whether participants had experienced problems with memory or concentration since the MVC. Participants who endorsed the presence of either of these items were considered to be experiencing cognitive symptoms. | ⁎ Question asked to participants: “Have you noticed any of the following since your accident?” |
Self-report questionnaires All participants completed the following self-report instruments designed to assess: (1) neck disability (Neck Disability Index [NDI])17; (2) pain severity (pain severity subscale of the Multidimensional Pain Inventory [MPI])18; (3) depressed mood (Center for Epidemiological Studies−Depression Scale [CES-D])19; (4) catastrophizing (Pain Catastrophizing Scale [PCS])20; (5) generalized pain-related anxiety (Pain Anxiety Symptoms Scale [PASS])21; and (6) fear of specific neck movements (Pictorial Fear of Activities Scale [PFActS]).22, 23 The first 5 measures have been widely used in study with diverse samples of participants with persistent pain. They have all been shown to have good to excellent psychometric properties. The PFActS is an instrument that was designed by the current investigators to assess the extent to which people with recent WADs are fearful of engaging in activities that might stress their necks. The PFActS consists of 72 photographs of a model engaging in activities that stress the cervical spine to a greater or lesser extent. Neck position (ie, extension, flexion, rotation), extent of cervical movement (minimal, extreme), arm position (ie, side, shoulder height, above head), and loading (ie, presence or absence of a standard object) are manipulated in a factorial fashion in the PFActS. The PFActS has shown good reliability and validity in samples of patients who have sustained WADs.22, 23 Neuropsychologic Tests Wechsler Memory Scale−Third Edition The WMS-III is among the most widely used measures of memory and has been used in numerous studies examining TBI24 and WADs.4, 9, 25 Its 8 indices (ie, auditory immediate, visual immediate, immediate, auditory delayed, visual delayed, auditory recognition, general memory, working memory tasks) provide comprehensive information about several different memory functions, and the working memory index has been considered a measure of attention and concentration.26 Trail-Making Test The TMT is part of the Halstead-Reitan Neuropsychological Battery.27 It requires people to connect consecutively numbered circles (Part A [TMT-A]) and then alternating letters and numbers (Part B [TMT-B]). The score is the time to complete each task. The test has variously been described as a test of attentional capacity, sequencing, visuomotor speed, cognitive flexibility, and set shifting ability.28, 29 It has been used widely in the neuropsychologic assessment of TBI24 and WADs.4, 6, 9, 10 Statistical Methods For purposes of the primary analysis, composite WMS-III scores were derived by calculating each participant’s average score on the 8 WMS indices. Participants were subdivided into 2 groups: CS+ (endorsed memory problems, concentration problems, or both) and CS− (did not endorse either problem). The primary analysis consisted of a t test, with CS+ versus CS− status as the independent variable and composite WMS-III as the dependent variable. A power analysis revealed that with α set at .05, at least 63 participants per group would be needed in order to detect a difference of 0.5 standard deviations with power of 0.8. The actual sample sizes (93 for CS+; 110 for CS−) were substantially greater than this minimum. In further tests of associations between reported cognitive symptoms and actual neuropsychologic test performance, a series of t tests with Bonferroni adjustment were performed, in which CS+ and CS− participants were compared on the 8 WMS-III indices and on TMT-A and TMT-B. We then performed a series of univariate analyses to determine whether CS+ versus CS− status was related to demographic variables, accident variables, litigation status, use of centrally acting drugs, pain severity, emotional dysfunction, neck disability, and endorsement of symptoms on the symptom checklist. Variables found to be associated with CS+ versus CS− status were then entered into a multivariate logistic regression equation, with CS+ versus CS− as the dependent variable. To evaluate the possibility that cognitive symptoms might have been associated with neuropsychologic test performance among participants who were relatively severely impacted by their WAD, secondary analyses were performed, in which participants were divided into high and low subgroups with respect to pain intensity and neck disability. Relations between CS+ and CS− status and neuropsychologic test performance were examined within these subgroups. Results Sixty-six (32%) of the 203 participants reported memory problems, 84 (41%) reported problems concentrating, and 110 (54%) reported neither problems in memory or concentration. There was a strong association between reporting of the 2 symptoms; most participants reported either no cognitive symptoms or both memory and concentration problems (χ2 test=81.6, P<.001). For purposes of analysis, participants were divided into 2 groups: CS+ (endorsing 1 or 2 cognitive symptoms, n=93) and CS− (endorsing no cognitive symptoms, n=110). Differences Between Participants Who Endorsed the Presence of Cognitive Symptoms (CS+) and Those Who Did Not (CS−) We performed t tests and chi-square tests to determine whether CS+ and CS− participants differed in (1) demographic variables, (2) collision-related variables, (3) legal involvement, (4) use of centrally acting drugs, (5) pain intensity (MPI), (6) emotional functioning and coping (CES-D, PASS, PCS, PFActS), and (7) neck disability (NDI). Results are presented in table 1. Demographics, MVC-Related Variables, Legal Involvement, and Use of Centrally Acting Drugs There were no statistically significant associations between CS status and age, sex, education, income, perceived severity of the collision, estimated vehicle damage, consultation with an attorney, or use of centrally acting drugs (see table 1). Symptoms CS+ participants were significantly higher than those in the CS− group in pain severity (95% confidence interval [CI], 1.97– 2.45; P<.01), depressed mood (95% CI, 13.41–16.73; P<.001), pain anxiety (95% CI, 53.1–61.9; P<.01), catastrophizing (95% CI, 9.66–12.94; P<.01), fear of specific movements (95% CI, 1.20–1.85; P<.001), and perceived disability (95% CI, 9.32–11.68; P<.001) (see table 1). Neuropsychologic Deficits The t tests revealed that CS+ and CS− participants did not perform differently on the WMS-III composite score or on either the TMT-A or TMT-B. Furthermore, t tests on each of the 8 WMS-III index scores failed to show any significant differences between CS+ and CS− participants. Table 3 provides the performance means on the individual WMS-III indices and the TMT-A and TMT-B for CS+ and CS− participants combined, along with normative data for the tests reported in the literature. Study participants performed at least as well as normative samples on all of the measures, indicating that in the aggregate they were well within a normal range. To determine whether the high education level of our participants accounted for their good performance on the WMS-III and TMT, we performed follow-up analyses on the subset of our cohort (n=79) who had not completed college. The performance of these participants did not differ from that of normative samples on either the WMS-III indices or the TMT. | ⁎ Normative data for the WMS are in WAIS-III.26 Normative data for the TMT among people aged 35 to 44 years (n=39) are taken from Tombaugh.29 |
Endorsement of Physical Symptoms The 38-item symptom checklist is shown in table 2, along with the percentages of CS+ and CS− participants who endorsed each symptom. To assess the possibility that participants’ endorsement of the memory and concentration items reflected a general set to endorse the presence of symptoms, the first and third authors grouped selected items from the entire symptom checklist into 5 groups: (1) cognitive problems, (2) pain/neck: symptoms that suggested a cervical spine problem (eg, tingling in arms or hands), (3) pain/nonspecific: symptoms that were consistent with a persistent pain problem but were not specific to a cervical spine condition (eg, sleep disturbance), (4) pain/not neck: symptoms that suggested pain syndromes other than ones involving the cervical spine (eg, abdominal pain), and (5) not pain: symptoms that appeared to have nothing to do with pain (eg, shortness of breath). Twenty-five items could be reliably assigned to a group. Each participant received 5 scores indicating how many items within each of the 5 groups he/she had endorsed. Each participant also received a total symptoms score on the checklist, indicating how many of the 36 items excluding the ones dealing with memory or concentration he/she endorsed. The t tests revealed significant, Bonferroni adjustment, covariation between endorsement of cognitive items, and endorsement of other symptoms on the symptom checklist. Specifically, CS+ participants were significantly more likely than CS− participants to endorse pain/neck, pain/nonspecific, pain/not neck, and not pain items (all P<.001). They also had significantly higher total symptoms scores (P<.001). Predictors of CS+ Versus CS− Status: Multivariate Analysis A forward conditional logistic regression analysis was performed, with CS+ versus CS− as the dependent variable. Independent variables were the total symptoms score and all the variables (see table 1) that had been found to be associated with CS status in univariate analyses: namely, pain intensity (MPI), NDI, CES-D, PASS, PCS, and PFActS scores. In this multivariate analysis, only the total symptoms score was found to predict CS status (Wald χ2=45.69, P<.001). Secondary Analyses To evaluate the possibility that cognitive symptoms might have been related to neuropsychologic test performance among participants who were relatively severely impacted by their WAD, the association between CS+ versus CS− status and neuropsychologic performance was evaluated only for participants in the top third of the distribution of pain intensity scores. No statistically significant effects of CS+ versus CS− status were identified on either the WMS-III or the TMT. Comparable negative results occurred when participants in the top third of the distribution of NDI severity scores were selected. Discussion The finding that 46% of the participants reported memory and concentration problems is consistent with the high prevalence of these symptoms reported by other investigators.4 The hypothesis that cognitive symptoms would be associated with poor performance on specific neuropsychologic tests was not confirmed. Thus, the present study failed to replicate the findings reported by of Di Stefano and Radanov.4 The discrepancy between our results and those of Di Stefano and Radanov is not dramatic because they found performance differences between participants who reported cognitive problems and ones without such reports on only a small subset of the multiple neuropsychologic tests they administered. The discrepancy observed could be the result of several differences between the 2 studies, including the neuropsychologic tests selected, differences between the 2 cohorts in chronicity, and method of participant recruitment. Conclusions In the aggregate, participants in the present study performed at least as well as “normal” individuals. Thus, we did not find the deficits in neuropsychologic performance logical testing or advanced imaging studies designed to identify structural brain lesions. An appropriate alternative strategy would be one of watchful waiting combined with reassurance and education about the normal aftermath of an MVC to reduce the disability and distress of people with WADs grades I and II.30, 31 References 1. 1Spitzer WO, Skovron ML, Salmi LR, et al. Scientific monograph of the Quebec Task Force on Whiplash-Associated Disorders: redefining “whiplash” and its management. Spine. 1995;20(8 Suppl):1S–73S. MEDLINE 2. 2Quinlan KP, Annest JL, Myers B, Ryan G, Hill H. Neck strains and sprains among motor vehicle occupants-United States, 2000. Accid Anal Prev. 2004;36:21–27. MEDLINE |
CrossRef
3. 3Turk DC, Okifuji A. What factors affect physicians’ decisions to prescribe opioids for chronic noncancer pain patients?. Clin J Pain. 1997;13:330–336. MEDLINE |
CrossRef
4. 4Di Stefano G, Radanov BP. Quantitative and qualitative aspects of learning and memory in common whiplash patients: a 6-month follow-up study. Arch Clin Neuropsychol. 1996;11:661–676.
CrossRef
5. 5Ferrari R, Russell AS, Carroll LJ, Cassidy JD. A re-examination of the whiplash associated disorders (WAD) as a systemic illness. Ann Rheum Dis. 2005;64:1337–1342. MEDLINE |
CrossRef
6. 6Gimse R, Bjorgen IA, Tjell C, Tyssedal JS, Bo K. Reduced cognitive functions in a group of whiplash patients with demonstrated disturbances in the posture control system. J Clin Exp Neuropsychol. 1997;19:838–849. MEDLINE |
CrossRef
7. 7Radanov BP, Bicik I, Dvorak J, Antinnes J, von Schulthess GK, Buck A. Relation between neuropsychological and neuroimaging findings in patients with late whiplash syndrome. J Neurol Neurosurg Psychiatry. 1999;66:485–489. MEDLINE |
CrossRef
8. 8Radanov BP, Dvorak J. Impaired cognitive functioning after whiplash injury of the cervical spine. Spine. 1996;21:392–397. MEDLINE |
CrossRef
9. 9Di Stefano G, Radanov BP. Course of attention and memory after common whiplash: a two-years prospective study with age, education and gender pair-matched patients. Acta Neurol Scand. 1995;91:346–352. MEDLINE |
CrossRef
10. 10Bosma FK, Kessels RP. Cognitive impairments, psychological dysfunction, and coping styles in patients with chronic whiplash syndrome. Neuropsychiatry Neuropsychol Behav Neurol. 2002;15:56–65. 11. 11Kessels RP, Aleman A, Verhagen WI, van Luijtelaar EL. Cognitive functioning after whiplash injury: a meta-analysis. J Int Neuropsychol Soc. 2000;6:271–278. MEDLINE |
CrossRef
12. 12Kessels RP, Keyser A, Verhagen WI, van Luijtelaar EL. The whiplash syndrome: a psychophysiological and neuropsychological study towards attention. Acta Neurol Scand. 1998;97:188–193. MEDLINE |
CrossRef
13. 13Guez M, Brannstrom R, Nyberg L, Toolanen G, Hildingsson C. Neuropsychological functioning and MMPI-2 profiles in chronic neck pain: a comparison of whiplash and non-traumatic groups. J Clin Exp Neuropsychol. 2005;27:151–163. MEDLINE |
CrossRef
14. 14Henry GK, Gross HS, Herndon CA, Furst CJ. Nonimpact brain injury: neuropsychological and behavioral correlates with consideration of physiological findings. Appl Neuropsychol. 2000;7:65–75. MEDLINE |
CrossRef
15. 15Parker RS, Rosenblum A. IQ loss and emotional dysfunctions after mild head injury incurred in a motor vehicle accident. J Clin Psychol. 1996;52:32–43. MEDLINE |
CrossRef
16. 16Antepohl W, Kiviloog L, Andersson J, Gerdle B. Cognitive impairment in patients with chronic whiplash-associated disorder—a matched control study. NeuroRehabilitation. 2003;18:307–315. MEDLINE 17. 17Vernon H, Mior S. The Neck Disability Index: a study of reliability and validity. J Manipulative Physiol Ther. 1991;14:409–415. MEDLINE 18. 18Kerns RD, Turk DC, Rudy TE. The West Haven-Yale Multidimensional Pain Inventory (WHYMPI). Pain. 1985;23:345–356. Abstract |
Full-Text PDF (899 KB)
|
CrossRef
19. 19Radloff L. A self-report depression scale for research in the general population. Appl Psychol Meas. 1977;1:385–392. 20. 20Sullivan MJL, Bishop SR, Pivik J. The Pain Catastrophizing Scale: development and validation. Psychol Assess. 1993;7:524–532.
CrossRef
21. 21McCracken LM, Zayfert C, Gross RT. The Pain Anxiety Symptoms Scale: development and validation of a scale to measure fear of pain. Pain. 1992;50:67–73. Abstract |
Full-Text PDF (871 KB)
|
CrossRef
22. 22Robinson JP, Burwinkle T, Turk DC. Assessment of fear among patients with neck pain: a pictorial instrument vs. questionnaires. Seattle: IASP Pr; 2005;. 23. 23Burwinkle TN, Robinson JP, Turk DC. Psychometric properties of a pictorial instrument for assessing fear of activity – PFActS. Seattle: IASP Pr; 2005;. 24. 24Rabin LA, Barr WB, Burton LA. Assessment practices of clinical neuropsychologists in the United States and Canada: a survey of INS, NAN, and APA Division 40 members. Arch Clin Neuropsychol. 2005;20:33–65. MEDLINE |
CrossRef
25. 25Kischka U, Ettlin T, Heim S, Schmid G. Cerebral symptoms following whiplash injury. Eur Neurol. 1991;31:136–140. MEDLINE |
CrossRef
26. 26WAIS-III. WMS-III. Technical manual. San Antonio: The Psychological Corp; 2002;. 27. 27In: Lezak MD editors. Neuropsychological assessment. 4th ed.. New York: Oxford Univ Pr; 2004;. 28. 28Lange RT, Iverson GL, Zakrzewski MJ, Ethel-King PE, Franzen MD. Interpreting the trail making test following traumatic brain injury: comparison of traditional time scores and derived indices. J Clin Exp Neuropsychol. 2005;27:897–906. MEDLINE |
CrossRef
29. 29Tombaugh TN. Trail Making Test A and B: normative data stratified by age and education. Arch Clin Neuropsychol. 2004;19:203–214. MEDLINE |
CrossRef
30. 30McClune T, Burton AK, Waddell G. Evaluation of an evidence based patient educational booklet for management of whiplash associated disorders. Emerg Med J. 2003;20:514–517.
CrossRef
31. 31Schmand B, Lindeboom J, Schagen S, Heijt R, Koene T, Hamburger HL. Cognitive complaints in patients after whiplash injury: the impact of malingering. J Neurol Neurosurg Psychiatry. 1998;64:339–343. MEDLINE |
CrossRef
a Department of Physical Medicine and Rehabilitation, University of Washington, Seattle, WA b Department of Anesthesiology, University of Washington, Seattle, WA.  Reprint requests to Dennis C. Turk, PhD, Dept of Anesthesiology, Box 356540, University of Washington, Seattle, WA 98195
Supported in part by the National Institute of Arthritis and Musculoskeletal Diseases and Skin Diseases, National Institutes of Health (grant no. AR47298). 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. PII: S0003-9993(07)00197-9 doi:10.1016/j.apmr.2007.03.004 © 2007 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved. | |
|
FULL TEXT