Sport concussion and attention deficit hyperactivity disorder in student athletes: A cohort study

Abstract

Background: Attention deficit hyperactivity disorder (ADHD) is associated with impulsive behavior and inattention, making it a potential risk factor for sport-related concussion (SRC). The objectives of this study were to determine whether ADHD is an antecedent risk factor for SRC and whether ADHD complicates recovery from SRC in youth athletes.

Methods: Student athletes with a history of SRC were evaluated for the presence of ADHD using diagnostic interview and to determine whether ADHD symptoms began before or after SRC. Concussion-specific measures of concussive symptoms and cognitive function were compared in SRC + ADHD and SRC + No ADHD groups to assess SRC recovery between groups.

Results: ADHD was overrepresented in youth with SRC compared with population rates. ADHD was found to be an antecedent risk factor for SRC, with age at ADHD onset earlier than the date of SRC. Student athletes with SRC and ADHD reported more concussive symptoms compared with athletes without ADHD and were more likely to have a history of greater than one concussion.

Conclusions: The results of this study support our hypothesis that ADHD is an antecedent risk factor for SRC and may contribute to a more complicated course of recovery from SRC. Future research should focus on determining whether screening, diagnosis, and treating ADHD in youth athletes may prevent SRC. Providers that care for youth athletes with ADHD should be aware of the vulnerabilities of this population toward SRC and its complications.

Figures

Figure 1. Clinical correlates of SRC in student athletes with and without ADHD

(A) Rates of ADHD in the US population and the SRC patients from this study. (B) Mean age at onset of ADHD and SRC for student athletes with SRC + ADHD. (C) Percent of student athletes in the SRC + No ADHD and SRC + ADHD groups who have sustained more than one head injury. ADHD = attention deficit hyperactivity disorder; SRC = sport-related concussion.

Figure 2. Concussion symptoms and severity in SRC student athletes with and without ADHD

(A) Immediate postconcussion assessment and cognitive testing (ImPACT) and adapted British Columbia postconcussion symptom inventory (BC-PSI) results for student athletes with SRC + No ADHD and SRC + ADHD. Total symptom composite score on the ImPACT. (B) ImPACT and adapted BC-PSI results for student athletes with SRC + No ADHD and SRC + ADHD. Percent of patients with a total symptom composite score >5 on the ImPACT as determined by the median split. (C) ImPACT and adapted BC-PSI results for student athletes with SRC + No ADHD and SRC + ADHD. Percent of patients with >5 severe symptoms (severity >2) on the adapted version of the BC-PSI as determined by the median split. ADHD = attention deficit hyperactivity disorder; SRC = sport-related concussion.

Figure 3. Executive functioning in SRC student athletes with and without ADHD

Behavior rating inventory of executive functioning (BRIEF) subscale scores of student athletes with SRC + No ADHD and SRC + ADHD. Standardized mean difference (95% confidence interval) for each significant subscale: inhibit: −1.17 (−1.55 to −0.78); shift: −0.43 (−0.79 to −0.07); self-monitoring: −0.77 (−1.14 to −0.40); initiate: −0.77 (−1.14 to −0.04); working memory: −1.18 (−1.57 to −0.80); plan/organize: −0.94 (−1.32 to −0.57); organize materials: −0.88 (−1.25 to −0.50); MI: −1.05 (−1.43 to −0.67); BRI: −0.78 (−1.15 to −0.41); GEC: −1.07 (−1.45 to −0.69). ADHD = attention deficit hyperactivity disorder; BRI = Behavioral Regulation Index; GEC = Global Executive Composite; MI = Metacognition Index; SRC = sport related concussion.