Characteristics and Outcomes of Athletes With Slow Recovery From Sports-Related Concussion: A CARE Consortium Study

Abstract

Background and objectives: Some athletes experience a slow recovery after sport-related concussion (SRC). There is little agreement on what constitutes slow recovery, however, and minimal data on the prevalence, predictors, or prognosis for this group. The objectives of this study were to apply an operationalized definition of slow recovery and characterize predictors and long-term prognosis of these individuals.

Methods: This is a prospective multisite observational study of collegiate athletes. Participants underwent multimodal assessments preseason and 5 additional time points after SRC. Time from injury to initiation of return to play progression (asymptomatic timepoint) and from injury to return to play (RTP) were the primary markers of recovery.

Results: One thousand seven hundred fifty-one concussed male and female collegiate athletes were studied. Eighty percent of participants reached the asymptomatic and/or RTP time points by days 14 and 24, respectively. Slow recovery was thus defined as exceeding 1 or both of those intervals (n = 399). This group was statistically more likely to be female (41.1% vs 35.6%, p = 0.05), have higher initial postinjury SCAT symptom severity scores (mean [SD]: 36.6 [23.4] vs 25.4 [19.9], p < 0.001), lower postinjury Standardized Assessment of Concussion scores (mean [SD]:25.74 [2.98] vs 26.26 [2.85], p = 0.004), perform worse on the postinjury Balance Error Scoring System (mean [SD]: 17.8 [8.9] vs 15.9 [8.5], p < 0.01), have fewer assessments in the first 14 days after injury (mean [SD]: 48.8 [29.7] vs 67.9 [24.6], p < 0.01), and be injured in practice (70.7% vs 65.1%, p = 0.04). 77.6% of the slow recovery group returned to play within 60 days of injury, and 83.4% (n = 349) returned to play within 90 days of injury. Only 10.6% had not returned to play 6 months postinjury.

Discussion: This study suggests an overall favorable prognosis for slowly recovering athletes and provides data for athletes and medical teams to consider in calibrating RTP expectations and making decisions about medical disqualification vs ongoing engagement in their sport.

Figure 1. Cohort Consort Diagram

Figure 2. Kaplan-Meier Curve for the Probability of Return to Play for the Slow Recovery Group

Figure 2 shows the Kaplan-Meier curve (red line) for the probability of return to play for the slow recovery group (n = 399). The blue and green lines represent the 95% point-wise confidence intervals for the Kaplan-Meier curve.