The Effect of Cognitive Rest as Part of Postconcussion Management for Adolescent Athletes: A Critically Appraised Topic

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1 Journal of Sport Rehabilitation, 2017, 26, Human Kinetics, Inc. CRITICALLY APPRAISED TOPIC The Effect of Cognitive Rest as Part of Postconcussion Management for Adolescent Athletes: A Critically Appraised Topic Rachel S. Johnson, Mia K. Provenzano, Larynn M. Shumaker, Tamara C. Valovich McLeod, and Cailee E. Welch Bacon Clinical Scenario: It is hypothesized that cognitive activity following a concussion may potentially hinder patient recovery. While the recommendation of cognitive rest is often maintained and rationalized, a causal relationship between cognitive activity and symptom duration has yet to be established. Clinical Question: Does the implementation of cognitive rest as part of the postconcussion management plan reduce the number of days until the concussed adolescent patient is symptom free compared to a postconcussion management plan that does not incorporate cognitive rest? Summary of Key Findings: A thorough literature search returned 7 possible studies; 5 studies met the inclusion criteria and were included. Three studies indicated that increased cognitive activity is associated with longer recovery from a concussion, and, therefore, supported the use of cognitive rest. One study indicated that the recommendation for cognitive rest was not significantly associated with time to concussion symptom resolution. One study indicated that strict rest, defined as 5 days of no school, work, or physical activity; might prolong symptom duration. Clinical Bottom Line: There is moderate evidence to support the prescription of moderate cognitive rest for concussed patients. Clinicians who intend on implementing cognitive rest in their concussion protocols should be aware of inconsistencies and be open-minded to alternative treatment progressions while taking into consideration each individual patient and maintaining adequate patient-centered care principles. Strength of Recommendation: Grade B evidence exists that prescription of moderate cognitive rest for concussed patients may be beneficial as a supplement to physical rest as treatment for symptom reduction in adolescents. Keywords: return-to-learn, return-to-play, post-concussion symptom scale, mild traumatic brain injury Clinical Scenario Following concussion, it is hypothesized that cognitive activity may potentially hinder patient recovery. This is based on the theory that cognitive activity alters the metabolism of the brain, which could potentially delay the healing process of a traumatic brain injury. 1 While the recommendation of cognitive rest is often maintained and rationalized, a causal relationship between cognitive activity and symptom duration has yet to be established. Symptom severity and duration is recorded and assessed using different outcome measurement tools such as the Post-Concussion Symptom Scale (PCSS). 2 Return-to-play protocols for concussions are often stringent and clear in terms of the patient s return to physical activity. However, there are many discrepancies when it comes to return-tolearn guidelines that include limiting cognitive activities such as concentrating in school, playing video games, and reading. Many practitioners suggest both physical and cognitive rest for concussed patients, but this is something The authors are with Athletic Training Programs, A.T. Still University, Mesa, AZ. McLeod and Welch Bacon are also with the School of Osteopathic Medicine in Arizona, A.T. Still University, Mesa, AZ. Welch Bacon (cwelch@atsu.edu) is corresponding author. that may be difficult to fully implement for school-aged individuals due to the pressure and expectation to keep on top of schoolwork. Furthermore, while prescribing cognitive rest appears to pose no risk to the patient, 3 concrete evidence of the benefits of doing so are lacking. Clinical Question Does the implementation of cognitive rest as part of the postconcussion management plan reduce the number of days until the concussed adolescent patient is symptom free compared with a postconcussion management plan that does not incorporate cognitive rest? Summary of Search, Best Evidence Appraised, and Key Findings The literature was searched for studies that implemented the use of cognitive rest as an intervention for concussed, adolescent athletes. The literature search returned 7 possible studies; 5 studies 2 6 met the inclusion criteria and were included (3 retrospective cohort, 1 prospective cohort, 1, 2 retrospective chart reviews). 437

2 438 Johnson et al While 3 studies 2,4,5 indicated that increased cognitive activity is associated with longer recovery from a concussion, only 1 study 2 showed evidence to support the use of cognitive rest to reduce the number of symptomatic days One study 3 indicated that the recommendation for cognitive rest was not significantly associated with time to concussion symptom resolution. One study 6 indicated that strict rest defined as 5 days of no school, work, or physical activity might prolong symptom duration. Clinical Bottom Line There is moderate evidence to support the prescription of moderate cognitive rest for concussed patients. However, the findings show discrepancies in regards to the timeframe in which cognitive rest is thought to be most effective. The difficulties as to how cognitive rest is categorized, quantified, and executed should also be noted. Some evidence suggests that cognitive rest may actually exacerbate physical and emotional symptoms due to various reasons such as falling behind in school and decreased social interaction. Despite the lack of tangible, empirical evidence supporting the recommendation for cognitive rest, it remains widely suggested. 7 9 Clinicians who intend on implementing cognitive rest in their concussion protocols should be aware of these inconsistencies and be open minded to alternative treatment progressions while taking into consideration each individual patient and maintaining adequate patient-centered care principles. Strength of Recommendation Grade B evidence exists that prescription of moderate cognitive rest for concussed patients may be beneficial as a supplement to physical rest as treatment for symptom reduction in adolescents. Search Strategy Terms Used to Guide Search Strategy Patient/Client Group: Secondary school athletes OR adolescent athletes Intervention (or Assessment): cognitive rest AND concussion Comparison: absence of cognitive rest as an intervention Outcome(s): symptom free AND reported using the Post-Concussion Symptom Scale (PCSS) Sources of Evidence Searched The Cochrane Library MEDLINE CINAHL PubMed Additional resources obtained via review of reference lists and hand search Inclusion and Exclusion Criteria Inclusion Criteria Level 3 evidence or higher Studies that investigated effect of cognitive rest on concussion symptoms Studies that used the PCSS as an outcomes measurement tool Limited to English Language Limited to the past 10 years ( ) Exclusion Criteria Studies that initiated cognitive rest for postconcussion syndrome Studies that included patients with neurodevelopmental problems such as ADD/ADHD or learning disabilities Results of Search Five relevant studies 2 6 were located and categorized as shown in Table 1 (based on Levels of Evidence, Centre for Evidence Based Medicine, 2011). Table 1 Summary of Study Designs of Articles Retrieved Level of evidence 1 Randomized controlled trial Number located Author (year) 1 2 Retrospective cohort 3 2 Prospective cohort 1

3 Cognitive Rest Critically Appraised Topic 439 Best Evidence The studies in Table 2 were identified as the best evidence and selected for inclusion in this critically appraised topic (CAT). These studies were selected because they were considered level 3 evidence or higher and investigated the use of cognitive rest as an intervention for concussed, adolescent athletes. Implications for Practice, Education, and Future Research All 5 studies 2 6 appraised in this CAT addressed the prescription of cognitive rest and concussion symptoms. While all 5 studies 2 6 recommended cognitive rest as an intervention for resolution of concussive symptoms, only 1 study 2 showed evidence to support the use of cognitive rest to reduce the number of symptomatic days. As it stands, the majority of substantiating evidence supporting the use of cognitive rest for concussed patients comes from clinical expertise and opinion. 7 9 Furthermore, surveys of secondary school medical personnel have reported that only 40% of concussions managed by athletic trainers 10 and close to 60% of injuries managed by school nurses 11 receive instructions for academic adjustments. Cognitive rest, which is prescribed to reduce mental exertion and associated neurometabolic stressors that accompany cognitive activities, 12 should be considered for all patients following a concussion. Since concussion symptoms may be exacerbated by cognitive activity, patients should be instructed to avoid or limit mental challenges during the acute recovery phase. 12 For adolescent patients, these restrictions may include scholastic stressors, such as modifying school attendance or activities, as well as reducing technology use (eg, texting, gaming, computer use). However, since strict cognitive rest may in fact exacerbate symptoms, 6 clinicians must use an individualized approach to establish a tolerable level of cognitive activity during the concussion recovery phases. In addition, since symptoms from a concussion vary among individual patients, clinicians must remember that cognitive rest should be prescribed on a case-by-case basis. For those prescribing cognitive rest to concussed patients, it should also be noted that too much rest may cause feelings of isolation and depression due to reasons including, falling behind in school and being separated from teammates and friends. 3,5,6 Patients may also experience mood disturbances and sleep abnormalities due to a change in activity level, which can contribute to undesirable outcomes such as prolonged or exacerbated emotional and physical symptoms. 6 It should also be pointed out that as practitioners, we do not look for correlations and trends where there are none; as 2 studies 3,4 proposed, patients reporting higher and more severe symptoms are more likely to reduce activity level through physician recommendation as well as voluntarily. While these patients often times have prolonged symptom duration, this may not correlate directly to their adherence to a program including cognitive rest but instead be due to natural variation. To help determine which types of cognitive activities should be reduced following a concussion, clinicians may consider using a tool, such as the PCSS, to monitor symptom severity throughout recovery. While there are a variety of tools available to assess postconcussion symptoms, the PCSS, 2 is a symptom reporting scale that was designed to assist in formally documenting the subjective nature of postconcussion symptoms in a more objective manner and allows clinicians to categorize symptoms into factors, including physical/somatic, cognitive, emotional, and sleep. 13 The scale uses a 7-point Likert scale, ranging from 0 (experiencing no symptoms) to 6 (experiencing severe symptoms), and assesses the severity of 22 different symptoms. Scores on the PCSS range from 0 to 132; the higher the score, the more severe the patient is experiencing symptoms. 2 The PCSS has been reported to have excellent internal consistency (α = 0.93) for concussed athletes and ranged from 0.88 to 0.94 over multiple populations. The primary benefit of using the PCSS is that it can be used frequently, as often as day-to-day, for retesting. 13 Thus, clinicians can use the PCSS to assess a patient s current symptoms and determine if particular cognitive activities should be minimized until symptoms are diminished. When investigating the effects of cognitive rest on symptom resolution in concussed adolescents, confounding factors such as sex, age, history of concussion, and sport may need to be taken into consideration. One study 6 demonstrated that females may be more likely to have a higher PCSS score than males. Another study 4 reported that females are more likely to suffer prolonged symptoms when compared with male athletes. It was also discussed in 1 study 4 that younger athletes tend to recover slower than their older counterparts. While it may be beneficial to look further into why this is, Thomas et al 6 proposed that this could be due to patients inability to accurately articulate their symptoms. While consistent evidence is lacking on the effect of prior history of concussion, determining whether a patient has suffered amnesia, as opposed to loss of consciousness, could be a reliable predictor of cognitive deficits. 4 The effects of cognitive rest on concussed patients should be further researched. To draw more concrete conclusions, cognitive rest should be more thoroughly defined in terms of length, degree and type. It is also recommended that patient compliance should ideally be monitored if possible. Neuroimaging and electrophysiological assessment tools may be used to better assist in the understanding of how different types of rest activate the brain. Other possible research studies could include comparing symptom resolution between patients following a standard concussion protocol and those following a multifaceted protocol as well as developing a graded return to cognitive activity. This CAT should be reviewed in 2 years or when additional information has

4 Table 2 Characteristics of Included Studies Participants 99 patients (11-22 yrs, 13.7 ± 1.3 yrs) 184 patients (8-26 yrs, 15 ± 3 yrs) 86 patients (Males 15.81± 1.35, females ± 1.32 yrs) Inclusion Criteria: (1) report to emergency department (ED) with mild traumatic brain injury (mtbi)/concussion (2) chief complaint of injury to the head including associated mechanism with the potential to have sustained a direct force or transmitted force to the head (3) years old Inclusion Criteria: (1) patients seen in the clinic and diagnosed with a sportrelated concussion who were symptom-free by the end of the study period (2) patients with injury mechanisms and forces similar to those observed in sports Inclusion Criteria: records needed to include (1) the patient s current academic status (2) information pertaining to post injury activity level in sufficient detail to accurately categorize the patient (3) the injury must have been sustained during sport participation and (4) data from at least 2 clinical follow up visits were available Exclusion Criteria: (1) non- English speaking and/or guardian could not consent in English (2) diagnosed with intellectual disability (IQ < 70) or a previous mental defect or diseases (attention deficit disorder, attention deficit hyperactivity disorder or learning disability) (3) diagnosed with intracranial injury (4) no legal guardian present (5) were being admitted (6) had conditions that interfered with valid assessment of signs and symptoms, neurocognitive testing, or balance testing (7) if the clinician was uncomfortable with the study procedures (8) if the patient lived >1 hour away from the hospital conducting the study Exclusion Criteria: (1) patient s with incomplete medical records, (2) patients in whom alternate diagnoses were being considered (3) patient s who were not recovered by the end of the study (4) those with more severe injury mechanisms and forces Exclusion Criteria: (1) patient s with a history of learning disability, seizure disorder or attention deficit disorder were not included in our study (2) patients who were taking any form of medication at the time of injury and subsequent clinical evaluations were also excluded 49 patients (14-23 yrs, 15 ± 2.5 yrs) Inclusion Criteria:(1)high school to college-aged individuals(2) who sustained a concussion and (3) were referred to the Sports Concussion Center of New Jersey (SCCNJ) for assessment and management between April 2010 and September 2011 Exclusion criteria: No exclusion criteria were given. 335 patients (8-23 yrs, mean 15 ± 2.6 yrs) Inclusion Criteria: (1) presented to the sports concussion clinic of Boston Children s Hospital (2) patients presented within 3 weeks of injury (3) completed the intake form (4) completed all follow-up forms (5) diagnosed with a sport-related concussion/concussion resulting from a similar mechanism Exclusion Criteria: (1) patients with incomplete medical records (2) patients with alternative diagnoses being considered (3) patients who had more severe injury mechanism (continued) 440

5 Table 2 (continued) Intervention investigated Patients who reported to the Children s Hospital of Wisconsin between May 2010 and December 2012 were eligible for this study if they fit the criteria. Patients were randomly assigned to the intervention (strict rest) or control (usual care) groups Strict Rest: maintain 5 days of strict rest at home, followed by a stepwise return to activity, ACE-ED care plan A chart review was performed of clinic patients evaluated for concussion during the 21 month period from November 1, 2007 to July 31, 2009 A chart review was performed through a university hospital system s sports medicine concussion program during the and academic years Cognitive rest was recommended to 85 athletes An activity intensity scale (AIS) was developed for the purpose of this study to categorize activity level between patients Cognitive rest was only considered recommended if it was explicitly mentioned in the medical record Return to play was a categorical variable scored as the athlete was returned to play (yes) or not returned to play (no) in the same event in which the concussion was sustained Patients were documented if they were referred to the SCCNJ for assessment and management between April 2010 and September 2011 Patients underwent the standard protocol of SCCNJ that included, in this order: (1) completion of intake forms and required paperwork (2) interview/clinical history exam of patients (3) completion of ImPACT postconcussion testing (4) explanation to patient/ parents of ImPACT results and prescription of cognitive and physical rest with verbal instructions, take home report, and instructional handouts and (5) follow-up examination, no sooner than 1 week later, that included the ImPACT postconcussion testing, clinical interview for update in status, and prescription for the next steps in the recovery process At first postconcussion assessment, patients were advised to engage in 1 full week of rest, before any follow-up examinations or retesting. At second postconcussion exam, a plan was formulated, depending on the patient s current level of symptoms, which may include more rest or a transition to part or full days of school with academic accommodations A was performed with patients who reported to the Sports Concussion Clinic within 3 weeks of injury between October 2009 to July The independent effect of cognitive activity on concussion symptom duration was assessed. (continued) 441

6 Table 2 (continued) Usual Care: treating attending physician was free to verbally recommend activity restrictions as they saw fit, ACE-ED care plan Outcome measure(s) (1) 3-Day Activity Diary (1) Duration of postconcussion symptoms was used as the primary outcome (1) Composite scores gathered from ImPACT testing were evaluated as individual outcome measures (2) 7-Day Activity Diary (2) Recovery was defined as: Symptom-free both at rest and with exertion after discontinuing any medication prescribed for postconcussion symptoms, computerized neurocognitive test scores at or above baseline values when available, and BESS scores at baseline values when available (2) Symptom status was recorded as a total symptom score and was assessed by PCSS testing performed at each follow-up visit (3) Post-Concussion Symptom Scale (PCSS) (3) Return to play was a categorical variable scored as the athlete was returned to play (yes) or not returned to play (no) in the same event in which the concussion was sustained (4) Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) computerized test battery (5) Paper ancillary neuropsychological test battery (Hopkins Verbal Learning Test, Trail Making Test Parts A & B, Symbol Digit Modalities Test, Letter-Number Sequencing from the Wechsler Scales, Controlled Oral Word Association Test (Verbal Fluency) (6) Balance Error Scoring System (BESS) (1) PCSS score (1) PCSS score (2) Immediate Post-Concussion Assessment (2) Cognitive Activity Scale (3) ImPACT composite scores (continued) 442

7 Table 2 (continued) Main findings Both groups had ~20% decrease in energy expenditure and physical activity in the first 5 days postinjury. Usual care group reported more total hours in high and moderate mental activity on days 2-5 than strict rest group (8.33 [C], 4.86 [I], P =.03). In both groups >60% of participants experienced symptom resolution during the follow-up period (67% [C] vs. 63% [I], P =.82). It took 3 days longer for 50% of patients in the strict rest group to report symptom resolution compared with the usual care group (P =.08). The strict rest group reported greater total PCSS scores over the course of the 10-day follow-up period (187.9 vs 131.9, P <.03). A higher proportion of patients younger than 15 years old received a recommendation for cognitive rest when compared with older athletes (58% vs.37%, P <.01) Adjusted symptom scores decreased over time at each interval, suggesting an improvement in the self-report of symptoms (P <.001) Mean symptom duration was significantly longer for athletes to whom cognitive rest was recommended (57% vs. 29%, P <.01) Neurocognitive scores demonstrated improvements over time (P.002) No independent relationship between the recommendation for cognitive rest and the duration of symptoms was found A trend between total symptom score and intensity of activity after concussion was established (P =.08) Despite limited published evidence, the recommendation of cognitive rest after a sportrelated concussion, particularly if initiated soon after injury, is likely beneficial Athletes with AIS = 3,4 were more impaired in visual memory than AIS = 2 (P.05) Removing student athletes from their normal routines and separating them from their friends and teammates further increases feelings of anxiety and isolation. A main effect was noted for AIS score on visual memory (P =.003) and reaction time P <.001) suggesting that athletes engaging in the highest activity levels (AIS = 4) had the worst visual memory (adjusted mean score = -2.22) scoring below the second percentile No differences with respect to age (P =.36), sex (P =.09), history of concussion (P =.11), or diagnosis of attention deficit disorder/learning disorder (P =.22) Participants showed significantly improved performance on the Immediate Post-Concussion Assessment and Cognitive Testing and decreased symptom reporting following prescribed cognitive and physical rest, regardless of the time between concussion and the onset of rest. With respect to change in symptom scores from posttest 1 and 2, there was no significant difference between the 3 groups in either symptom change scores from pretest to posttest time 2 (P =.96), or in symptom change scores from posttest 1 to posttest 2 (P =.44) The overall mean duration of symptoms was 43 ± 53 days The mean PCSS score at the initial clinical evaluation was 30 ± 26 days The mean difference in symptom duration did not differ significantly between school age (42 ± 39 days), junior high/high school (43 ± 55 days) age, or adults(39 ± 60 days) (P =.947). Patients in the highest quartile of cognitive activity days took statistically longer to recover than those in the first through third quartiles of cognitive activity days. Only total score on the PCSS at the initial visit and cognitive activity days were independently associated with duration of symptoms. (continued) 443

8 Table 2 (continued) No significant differences on ImPACT or BESS scores on days 3 or 10 between groups. The strict rest group performed better at day 3 (59.9 [C] vs 67.6 [I], P <.01) and worse at day 10 (71.5 [C] vs [I], P =.04) than the usual care group on the Symbol Digit Modalities Test. When the PCSS was analyzed by domain, assignment to the strict rest group contributed to higher physical symptom scores on days 2 and 3 and a trajectory of higher emotional symptoms throughout the follow-up. Female patients reported increased PCSS scores and decreased energy expenditure. Patients diagnosed with concussion based on postconcussion symptoms alone reported a higher PCSS at day 10 when randomized to strict rest (15.2 [I] vs. 7.7 [C], P =.04). Patients who presented to the ED with immediate signs of concussion trended toward lower PCSS scores at day 10 when randomized to strict rest (11.0 [I] vs [C], P =.22). Patients with a past medical history of concussion reported greater symptoms at day 10 when randomized to strict rest (15.1 [I] vs. 5.6 [C], P <.05). After an initial period of full cognitive rest, typically 2-7 days in duration, a gradual reemergence into schoolwork is recommended. Reaction times were the worst for AIS = 4 (adjusted mean score = 3.51) with performance below the first percentile, with reaction times slower than AIS = 2 The athletes who returned to play in the same contest performed better over time on visual memory subtests than those who did not return to play (P <.001) Age was associated with verbal memory (P =.02) and visual memory (P =.03) over time, with younger athletes performing more poorly on both composite scores Females performed worse on visual motor speed than males (P =.05) Analyses evaluating interactions among independent variables demonstrated an interrelationship among sex, return to play, and performance on visual memory tests (P <.001) Females who did not return to play had lower visual memory scores than those who did return to the event in which the concussion occurred (continued) 444

9 Table 2 (continued) Level of evidence Validity score* 6/10 NA NA NA NA Conclusion In the acute care setting, strict rest immediately after mtbi offers no benefit over the usual care. Clinicians should consider carefully the recommendations of prolonged absences from school to patients recovering from concussion The fact that only 2 ImPACT composite scores were sensitive to cognitive changes after concussion may be attributed to the fact that different cognitive domains are known to be served by different brain regions and systems The preliminary data from this study suggests that a period of cognitive and physical rest may be a useful tool of treating concussion-related symptoms; more research is to be done to specify the length of the prescribed rest period, and degree or nature of the prescribed rest. Those engaged in the highest levels of cognitive activity had the longest times to symptom resolution. Adolescents symptom reporting may be influenced by restricting activity. Clinicians should use a multifaceted approach to the evaluation and management of head injuries The incorporation of neuroimaging and electrophysiological assessment tools will better assist in understanding the mechanisms of rest and help identify the brain activation patterns associated with different kinds of rest. This article supports the use of cognitive rest. Further research is needed to determine the optimal ED discharge recommendations for adolescents after mtbi This article suggests that while limiting cognitive activity is associated with a shorter duration of symptoms, complete rest from cognitive activity may be unnecessary. *Validity scores were determined via the Physiotherapy Evidence Database (PEDro) scale. 445

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