- Former professional athletes who had experienced multiple concussions had cerebrospinal fluid (CSF) levels of total tau that were higher than those among healthy controls and lower than those among patients with Alzheimer’s disease (AD).
Why this matters
- Difficulty of predicting chronic traumatic encephalopathy, early diagnosis, differentiation from other neurologic disorders.
- Mean CSF total tau levels in former athletes:
- Higher vs healthy controls (349.3 vs 188.8 pg/mL; P=.003).
- Lower vs patients with AD (349.3 vs 857.0 pg/mL; P=.007).
- Former athletes vs patients with AD:
- Lower CSF phosphorylated tau181 (P=.001).
- Higher CSF β-amyloid (P<.001>
- 54.5% of former athletes had high CSF total tau (>300 pg/mL).
- Former athletes with high vs normal CSF total tau had:
- Lower fractional anisotropy values across all white matter tracts (P=.036).
- Lower t scores on Trail Making Test Part B (45.6 vs 62.3; P=.017).
- Cross-sectional cohort study:
- 22 former professional athletes sustaining multiple concussions.
- 5 healthy controls.
- 12 patients with AD.
- Main outcomes: CSF phosphorylated tau181, total tau, β-amyloid.
- Funding: Toronto General and Western Hospital Foundation; PSI Foundation; Canadian Institute of Health Research.
- Small sample size.
- Few female athletes.
- 2 MRI scanners used.
- Only single phosphorylated tau isoform studied.