Objective To determine the association between baseline symptoms and symptom frequency and severity one day post-concussion in college and high school athletes.

Design Prospective cohort.

Setting USA colleges (n=26) and high schools (n=210).

Subjects Concussed individuals (n=375; 314 males; 61 females) recruited from a baseline cohort (N=8,905).

Intervention Baseline presence or absence for each of the 20 items on a Graded Symptom Checklist (GSC).

Outcome measures GSC symptom frequency and severity one day post-concussion.

Results Individuals with baseline headache (χ²(1)=10.98; P<0.001), fatigue (χ²(1)=6.06; P=0.014), sleeping more than usual (χ²(1)=16.90; P<0.001), blurred vision (χ²(1)=20.48; P<0.001), light/noise sensitivity (χ²(1)=4.67; P=0.031), and mental fogginess (χ²(1)=6.08; P=0.014) reported these symptoms at a higher frequency post-concussion. Subjects reporting the following baseline symptoms had greater severity of the same symptom post-concussion: headache (Presence: median=2; IQR=1–4; Absence: median=2, IQR=0–3; P=0.004), fatigue (Presence: median=1; IQR=0–3; Absence: median=0, IQR=0–2; P=0.017), sleeping more than usual (Presence: median=1, IQR=0–3; Absence: median=0, IQR=0–0; P<0.001), blurred vision (Presence: median=1; IQR=0–2; Absence: median=0, IQR=0–0; P<0.001), sensitivity to light and noise (Presence: median=1, IQR=0–3; Absence: median=0, IQR=0–1; P=0.010), and fogginess (Presence: median=2, IQR=0–3; Absence: median=0, IQR=0–1; P=0.002). No other symptoms at baseline were associated with post-concussion symptom frequency or severity (P>0.05).

Conclusions Athletes reporting baseline symptoms, particularly those in physical and sleep-related domains, were more likely to report a higher frequency and severity of these same symptoms one day post-concussion. Understanding factors influencing post-concussion symptom recovery may inform clinical decision-making and offer selection criteria for appropriate active recovery strategies.

Competing interests None.