Reduced Concussion Symptom Burden in Early Adolescent Athletes Using a Head-Neck Cooling Device.

OBJECTIVE: To determine whether an investigational head-neck cooling device, Pro2cool, can better reduce symptom severity compared with standard postconcussion care in early adolescent athletes after a sports-related concussion. DESIGN: Prospective, longitudinal, randomized trial design conducted over a 28-day period. SETTING: Six pediatric medical centers in Ohio and Michigan. PARTICIPANTS: The study enrolled 167 male and female 12- to 19-year-old athletes who experienced a sports-related concussion within 8 days of study enrollment and registering a Sports Concussion Assessment Tool 5 (SCAT5) composite score >7. INTERVENTIONS: Pro2cool, an investigational head-neck cooling therapy device, was applied at 2 postinjury time points compared with postconcussion standard of care only. MAIN OUTCOME MEASURES: Baseline SCAT5 composite symptom severity scores were determined for all subjects. Sports Concussion Assessment Tool 5 scores for concussed athletes receiving cooling treatment were analyzed across 6 independent postenrollment time points compared with subjects who did not receive cooling therapy and only standard care. Adverse reactions and participate demographics were also compared. RESULTS: Athletes who received Pro2cool cooling therapy (n = 79) experienced a 14.4% greater reduction in SCAT5 symptom severity scores at the initial visit posttreatment, a 25.5% greater reduction at the 72-hour visit posttreatment, and a 3.4% greater reduction at the 10-day visit compared with subjects receiving only standard care (n = 88). Overall, 36 adverse events (increased blood pressure, decreased pulse, and dizziness) were reported, with 13 events associated with the device, of which 3 were classified as moderate in severity. CONCLUSIONS: This study demonstrates the efficacy and safety of head and neck cooling for the management of concussion symptoms in adolescent athletes of an age group for which little to no prior data are available.

Interpreting Clinical Reaction Time Change and Recovery After Concussion: A Baseline Versus Norm-Based Cutoff Score Comparison.

CONTEXT: Preseason testing can be time intensive and cost prohibitive. Therefore, using normative data for postconcussion interpretation in lieu of preseason testing is desirable. OBJECTIVE: To establish the recovery trajectory for clinical reaction time (RTclin) and assess the usefulness of changes from baseline (comparison of postconcussion scores with individual baseline scores) and norm-based cutoff scores (comparison of postconcussion scores with a normative mean) for identifying impairments postconcussion. DESIGN: Case-control study. SETTING: Multisite clinical setting. PATIENTS OR OTHER PARTICIPANTS: An overlapping sample of 99 participants (age = 19.0 ± 1.1 years) evaluated within 6 hours postconcussion, 176 participants (age = 18.9 ± 1.1 years) evaluated at 24 to 48 hours postconcussion, and 214 participants (age = 18.9 ± 1.1 years) evaluated once they were cleared to begin a return-to-play progression were included. Participants with concussion were compared with 942 control participants (age = 19.0 ± 1.0 years) who did not sustain a concussion during the study period but completed preseason baseline testing at 2 points separated by 1 year (years 1 and 2). MAIN OUTCOME MEASURE(S): At each time point, follow-up RTclin (ie, postconcussion or year 2) was compared with the individual year 1 preseason baseline RTclin and normative baseline data (ie, sex and sport specific). Receiver operating characteristic curves were calculated to compare the sensitivity and specificity of RTclin change from baseline and norm-based cutoff scores. RESULTS: Clinical reaction time performance declined within 6 hours (18 milliseconds, 9.2% slower than baseline). The decline persisted at 24 to 48 hours (15 milliseconds, 7.6% slower than baseline), but performance recovered by the time of return-to-play initiation. Within 6 hours, a change from baseline of 16 milliseconds maximized combined sensitivity (52%) and specificity (79%, area under the curve [AUC] = 0.702), whereas a norm-based cutoff score of 19 milliseconds maximized combined sensitivity (46%) and specificity (86%, AUC = 0.700). At 24 to 48 hours, a change from baseline of 2 milliseconds maximized combined sensitivity (64%) and specificity (61%, AUC = 0.666), whereas a norm-based cutoff score of 0 milliseconds maximized combined sensitivity (63%) and specificity (62%, AUC = 0.647). CONCLUSIONS: Norm-based cutoff scores can be used for interpreting RTclin scores postconcussion in collegiate athletes when individual baseline data are not available, although low sensitivity and specificity limit the use of RTclin as a stand-alone test.

Clinical Reaction Time After Concussion: Change From Baseline Versus Normative-Based Cutoff Scores.

CONTEXT: Pre-season testing is often used to establish baseline scores for post-concussion interpretation. However, pre-season testing can be time-intensive and cost-prohibitive, in which case normative data may be used for post-injury interpretation. OBJECTIVE: To compare change from baseline and normative-based cutoff scores in interpreting clinical reaction time (RTclin) following concussion. DESIGN: Prospective case-control study. SETTING: Multi-site study with testing completed in university athletic training rooms. PATIENTS OR OTHER PARTICIPANTS: An overlapping sample of 99 participants (age=19.0±1.1 years) evaluated within 6 hours post injury, 176 participants (age 18.9±1.1 years) evaluated 24-48 hours post injury, and 214 participants (18.9±1.1 years) evaluated at the time they were cleared to begin a return-to-play progression. Concussion participants were compared to 942 control participants (age=19.0±1.0 years) who did not sustain a concussion during the study period but completed preseason baseline testing one year apart. MAIN OUTCOME MEASURES: At each time point, follow-up RTclin (i.e., post injury or year 2) was compared to individualized year 1 preseason baseline RTclin and to normative baseline data (i.e., sex- and sport-specific). Receiver operating characteristic curves were used to compare sensitivity and specificity of RTclin change from baseline and normative-based cutoff scores. RESULTS: Within 6h, change from baseline of 16ms maximized combined sensitivity (52%) and specificity (78%, AUC=0.702), while normative-based cutoff scores of 19ms maximized combined sensitivity (45%) and specificity (86%, AUC=0.700). At 24-48h, change from baseline of 2ms maximized combined sensitivity (64%) and specificity (61%, AUC=0.666), while normative-based cutoff scores of 0ms maximized combined sensitivity (63%) and specificity (62%, AUC=0.647). CONCLUSIONS: Normative-based cutoff scores can be used for interpreting RTclin scores following concussion when individualized baseline data is not available, although low sensitivity and specificity may limit clinical use as a stand-alone test.

Clinical Reaction-Time Performance Factors in Healthy Collegiate Athletes.

CONTEXT: In the absence of baseline testing, normative data may be used to interpret postconcussion scores on the clinical reaction-time test (RTclin). However, to provide normative data, we must understand the performance factors associated with baseline testing. OBJECTIVE: To explore performance factors associated with baseline RTclin from among candidate variables representing demographics, medical and concussion history, self-reported symptoms, sleep, and sport-related features. DESIGN: Cross-sectional study. SETTING: Clinical setting (eg, athletic training room). PATIENTS OR OTHER PARTICIPANTS: A total of 2584 National Collegiate Athletic Association student-athletes (n = 1206 females [47%], 1377 males [53%], and 1 unreported (<0.1%); mass = 76.7 ± 18.7 kg; height = 176.7 ± 11.3 cm; age = 19.0 ± 1.3 years) from 3 institutions participated in this study as part of the Concussion Assessment, Research and Education Consortium. MAIN OUTCOME MEASURE(S): Potential performance factors were sex; race; ethnicity; dominant hand; sport type; number of prior concussions; presence of anxiety, learning disability, attention-deficit disorder or attention-deficit/hyperactivity disorder, depression, or migraine headache; self-reported sleep the night before the test; mass; height; age; total number of symptoms; and total symptom burden at baseline. The primary study outcome measure was mean baseline RTclin. RESULTS: The overall RTclin was 202.0 ± 25.0 milliseconds. Female sex (parameter estimate [B] = 8.6 milliseconds, P < .001, Cohen d = 0.54 relative to male sex), black or African American race (B = 5.3 milliseconds, P = .001, Cohen d = 0.08 relative to white race), and limited-contact (B = 4.2 milliseconds, P < .001, Cohen d = 0.30 relative to contact) or noncontact (B = 5.9 milliseconds, P < .001, Cohen d = 0.38 relative to contact) sport participation were associated with slower RTclin. Being taller was associated with a faster RTclin, although this association was weak (B = -0.7 milliseconds, P < .001). No other predictors were significant. When adjustments are made for sex and sport type, the following normative data may be considered (mean ± standard deviation): female, noncontact (211.5 ± 25.8 milliseconds), limited contact (212.1 ± 24.3 milliseconds), contact (203.7 ± 21.5 milliseconds); male, noncontact (199.4 ± 26.7 milliseconds), limited contact (196.3 ± 23.9 milliseconds), contact (195.0 ± 23.8 milliseconds). CONCLUSIONS: Potentially clinically relevant differences existed in RTclin for sex and sport type. These results provide normative data adjusting for these performance factors.