A Within-Subjects Comparison of Clinical Outcomes for Patients' First and Second Concussions

Identifying the 'Miserable Minority' Among Pediatric Patients Following Concussion

OBJECTIVES

To investigate whether there are empirically-detectable subgroups of concussion severity and recovery across three consecutive concussions, as well as to define risk factor and clinical assessment differences across subgroups.

METHODS

The present study was a retrospective chart review of 202 adolescents 13.17 ± 1.99 years old who presented to a concussion specialty clinic within 30 days of injury for multiple injuries between 2019 and 2020. Participants included patients from a specialty clinic for two (n = 202) or three (n = 68) total concussions. Latent class analysis (LCA) was used to identify subgroups based upon concussion symptom severity and recovery time. Risk factors (sex, age at first injury, and histories of anxiety, depression, migraine, motion sickness, ocular dysfunction, and attention-deficit/hyperactivity disorder [ADHD] or learning disability [LD]) were compared across subgroups.

RESULTS

A two-class solution yielded one group of 163 participants characterized by lower symptoms and shorter recovery times (80.7%, "normal") and 39 participants (19.3%, "miserable minority") characterized by higher symptoms and longer recovery times. Only female sex (OR = 4.91, p = 0.005) was a significant predictor of class membership. The miserable group presented for treatment nearly 4 days later (9.41 days) compared to the normal group (5.74 days) for the first injury, and almost 2 days later for the second injury (7.33 vs 5.26 days).

CONCLUSIONS

Approximately 1 in 5 patients who presented to a concussion specialty clinic for a repeat concussion were classified in the miserable minority subgroup. This subgroup was characterized by markedly higher initial symptom burdens and over double the recovery time.

LEVEL OF EVIDENCE

Retrospective cohort study, Level III evidence.

Symptom resolution following a repeat concussion within the same athlete

INTRODUCTION

Repeat sport-related concussion (SRC) is anecdotally associated with prolonged recovery. Few studies have examined repeat concussion within the same athlete. We sought to explore differences in symptom burden and recovery outcomes in an individual athlete's initial and repeat SRC.

METHODS

A retrospective within-subject cohort study of athletes aged 12-23 years diagnosed with two separate SRCs from 11/2017-10/2020 was conducted. Primary outcomes were initial symptom severity and time-to-symptom-resolution. Secondary outcomes included return-to-learn (RTL) and return-to-play (RTP) duration.

RESULTS

Of 868 athletes seen, 47 athletes presented with repeat concussions. Median time between concussions was 244 days (IQR 136-395). Comparing initial to repeat concussion, no differences were observed in time-to-clinic (4.3 ± 7.3vs.3.7 ± 4.6 days, p = 0.56) or initial PCSS (26.2 ± 25.3 vs. 30.5 ± 24.1, p = 0.32). While a difference was observed in time-to-symptom resolution between initial/repeat concussion (21.2 ± 16.3 vs. 41.7 ± 86.0 days, p = 0.30), this did not reach statistical significance. No significant differences were observed in time-to-RTL (17.8 ± 60.6 vs. 6.0 ± 8.3 days, p = 0.26) and RTP (33.2 ± 44.1 vs. 29.4 ± 39.1 days, p = 0.75). Repeat concussion was not associated with symptom resolution on univariate (HR 1.64, 95% CI 0.96-2.78, p = 0.07) and multivariable (HR 0.85, 95% CI 0.49-1.46, p = 0.55) Cox regression.

CONCLUSION

No significant differences in symptom duration and RTP/RTL were seen between initial/repeat concussion.

Risk of Two Sport-Related Concussions in the Same Year: Is the Second Concussion Worse?

OBJECTIVES

1) Evaluate the frequency of same-year, repeat concussions; (2) assess predictors of sustaining a repeat concussion; and (3) compare outcomes of athletes with repeat concussions with athletes with single concussion.

DESIGN

A retrospective, case-control study.

SETTING

Regional sports concussion center.

PATIENTS

Adolescents sustaining a sport-related concussions (SRC) from November 2017 to October 2020.

INDEPENDENT VARIABLES

Participants were dichotomized into 2 groups: (1) athletes with a single concussion; and (2) athletes with repeat concussions.

MAIN OUTCOME MEASURES

Between group and within group analyses were completed to look for differences in demographics, personal and family history, concussion history, and recovery metrics between the 2 groups.

RESULTS

Of 834 athletes with an SRC, 56 (6.7%) sustained a repeat concussion and 778 (93.3%) had a single concussion. Between group: Personal history of migraines (19.6% vs 9.5%, χ 2 = 5.795, P = 0.02), family history of migraines (37.5% vs 24.5%, χ 2 = 4.621, P = 0.03), and family history of psychiatric disorders (25% vs 13.1%, χ 2 = 6.224, P = 0.01) were significant predictors of sustaining a repeat concussion. Within group: Among those with a repeat concussion, initial symptom severity was greater (Z = -2.422; P = 0.02) during the repeat concussion and amnesia was more common (χ 2 = 4.775, P = 0.03) after the initial concussion.

CONCLUSIONS

In a single-center study of 834 athletes, 6.7% suffered a same-year, repeat concussion. Risk factors included personal/family migraine history and family psychiatric history. For athletes with repeat concussions, initial symptom score was higher after the second concussion, yet amnesia was more common after the initial concussion.