Concussions and MS risk
A new retrospective study using linked administrative databases in Ontario, Canada, identified 97,965 adolescents (11 to 18 years old) who suffered a concussion at ⩾1 and presented to an emergency department between 1992 and 2011. Cases were matched 1:3 with people who had not suffered a concussion based on age, sex, address, and index date. The main outcome was the diagnosis of MS, using a validated definition of MS diagnosis: ⩾1 hospitalization or ⩾5 medical bills within 2 years.
A concussion during adolescence was associated with a significantly higher risk of MS (risk ratio (RR) = 1.29, p = 0.03). Gender-specific analysis revealed that only males who suffered a concussion in adolescence were at increased risk of MS (HR = 1.41, p = 0.04).
This study supports an association between adolescent concussions and future MS diagnoses, highlighting the potentially serious long-term effects of concussions.