Edwina L Picon1, David L Perez2, Matthew J Burke3, Chantel T Debert4, Grant L Iverson5, William J Panenka6, Noah D Silverberg7. 1. Department of Psychology, University of British Columbia, Canada. Electronic address: epicon@psych.ubc.ca. 2. Departments of Neurology and Psychiatry, Massachusetts General Hospital, Harvard Medical School; USA. Electronic address: dlperez@partners.org. 3. Neuropsychiatry Program, Department of Psychiatry and Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto; Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, USA. Electronic address: matthew.burke@sunnybrook.ca. 4. Physical Medicine and Rehabilitation, Department of Clinical Neurosciences, Cumming School of Medicine, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Canada. Electronic address: Chantel.Debert@albertahealthservices.ca. 5. Department of Physical Medicine and Rehabilitation, Harvard Medical School; Spaulding Rehabilitation Hospital and Spaulding Research Institute; MassGeneral Hospital for Children Sports Concussion Program; & Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, USA. Electronic address: giverson@mgh.harvard.edu. 6. Department of Psychiatry, University of British Columbia; BC Mental Health and Substance Use Research Institute; BC Neuropsychiatry Program, Canada. Electronic address: will.panenka@ubc.ca. 7. Department of Psychology, University of British Columbia Rehabilitation Research Program, Vancouver Coastal Health Research Institute, Canada. Electronic address: noah.silverberg@ubc.ca.
Abstract
OBJECTIVE: Reporting of unexpected symptoms after concussion might, in some people, reflect a Functional Neurological Disorder (FND), Somatic Symptom Disorder (SSD), or exaggeration (feigning). This study aimed to determine whether reporting unexpected symptoms after concussion was associated with risk factors for FND/SSD, exaggeration, or both. METHOD: Adults with persistent symptoms following concussion (N = 77; 61% women) rated the presence and severity of unexpected neurological symptoms (from the Screening for Somatoform Symptoms scale, e.g., paralysis) and somatic symptoms (from the Patient Health Questionnaire-15, e.g., stomach pain) that did not overlap with post-concussion symptom scale items. The independent variables were risk factors for exaggeration (neuropsychological performance validity test failure and personal injury litigation) and predisposing and perpetuating factors for developing FND and/or SSD (e.g., fear avoidance behavior). RESULTS: When adjusting for all covariates, fear avoidance behavior was most strongly related to unexpected neurological symptoms (B = 0.11, 95% confidence interval = 0.05-0.18, p < .001), while current anxiety scores were most strongly related to unexpected somatic symptoms (B = 0.34, 95% confidence interval = 0.15-0.52, p < .001). Performance validity test failure and litigation were not significant predictors in either model. CONCLUSION: Unexpected neurological and other somatic symptoms after concussion should not be dismissed as exaggeration. Psychological factors thought to perpetuate FND and SSD (e.g., fear avoidance behavior) may contribute to unexpected symptoms following concussion. More research is needed at the intersection of FND, SSD, and persistent post-concussive symptoms.
OBJECTIVE: Reporting of unexpected symptoms after concussion might, in some people, reflect a Functional Neurological Disorder (FND), Somatic Symptom Disorder (SSD), or exaggeration (feigning). This study aimed to determine whether reporting unexpected symptoms after concussion was associated with risk factors for FND/SSD, exaggeration, or both. METHOD: Adults with persistent symptoms following concussion (N = 77; 61% women) rated the presence and severity of unexpected neurological symptoms (from the Screening for Somatoform Symptoms scale, e.g., paralysis) and somatic symptoms (from the Patient Health Questionnaire-15, e.g., stomach pain) that did not overlap with post-concussion symptom scale items. The independent variables were risk factors for exaggeration (neuropsychological performance validity test failure and personal injury litigation) and predisposing and perpetuating factors for developing FND and/or SSD (e.g., fear avoidance behavior). RESULTS: When adjusting for all covariates, fear avoidance behavior was most strongly related to unexpected neurological symptoms (B = 0.11, 95% confidence interval = 0.05-0.18, p < .001), while current anxiety scores were most strongly related to unexpected somatic symptoms (B = 0.34, 95% confidence interval = 0.15-0.52, p < .001). Performance validity test failure and litigation were not significant predictors in either model. CONCLUSION: Unexpected neurological and other somatic symptoms after concussion should not be dismissed as exaggeration. Psychological factors thought to perpetuate FND and SSD (e.g., fear avoidance behavior) may contribute to unexpected symptoms following concussion. More research is needed at the intersection of FND, SSD, and persistent post-concussive symptoms.
Authors: Camilla N Clark; Mark J Edwards; Bee Eng Ong; Luke Goodliffe; Hena Ahmad; Michael D Dilley; Shai Betteridge; Colette Griffin; Peter O Jenkins Journal: Brain Date: 2022-06-30 Impact factor: 15.255