Frequency of low ImPACT scores among adolescent and young adult student-athletes with attention-deficit/hyperactivity disorder and/or learning disorder

Introduction: Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by attention problems, excessive activity, and impulsivity - occurring in approximately 13% of children 12–17 years of age, and as many as 16% of older adolescents 18–22 years of age, with a greater prevalence in boys than girls. ADHD frequently co-occurs with specific learning disorder (LD), a neurodevelopmental disorder characterized by difficulties learning and using academic skills, such as reading, writing, and mathematics. Taken together, ADHD and/or LD are common among high school students and college students and can influence performance on computerized tests used in concussion management. However, normative data for widely used computer-based measures used in concussion management do not include reference samples with ADHD and/or LD. Previous research has documented the expected frequency of obtaining low scores on computer-based neuropsychological test measures among healthy, uninjured individuals, but few studies have examined the frequency of obtaining low scores in athletes with neurodevelopmental diagnoses, such as ADHD and/or LD. This study examined the frequency of low scores (i.e., multivariate base rates) on the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) for youth and young adults with self-reported ADHD and/or LD. Methods: The sample included 174,878 adolescent and young adult student-athletes who completed pre-season baseline neurocognitive assessments, who were assigned to the following independent groups: ADHD only (n = 45,215), LD only (n = 54,223), ADHD and LD (n = 45,737), No ADHD or LD (n = 47,684; “control athletes”). Results: Base rates of low scores were stratified by high school (e.g., 13–18) and collegiate age (e.g., 19–22) and sex. It was common for student athletes (all ages) with LD alone (i.e., 30–37%), or with both ADHD and LD (i.e., 24–31%), to obtain at least two low ImPACT composite scores, but not three low composite scores. However, it was relatively uncommon for control athletes (those without ADHD or LD) (i.e., 12–14%) or older athletes (ages 19–22) with ADHD (i.e., 14–15%) to obtain two (or more) low scores. Discussion: Having information relating to the base rates of low scores among uninjured athletes enhances the interpretation of ImPACT results among the broader population of student-athletes with and without neurodevelopmental disorders.