Epilepsy linked to dementia diagnosed before age 65
In a French cohort, dementia before 65 developed in 2.20% with newly diagnosed epilepsy versus 0.21% without epilepsy over 10 years.
The French observational cohort included 12,901 adults with newly diagnosed epilepsy, 64,083 with existing epilepsy and 129,010 without epilepsy. Participants were aged 30–55 at entry; their mean age was 44, and 55.5% were female.
Over 10 years, dementia before age 65 developed in 2.20% with newly diagnosed epilepsy, 1.74% with existing epilepsy and 0.21% without epilepsy. The association weakened when researchers delayed the start of follow-up, but persisted beyond five years. Separate case-control studies compared 11,360 dementia cases with 113,600 matched controls in France and 16,433 cases with 164,330 controls in Sweden. The French cases were aged 40–64. Across both countries, epilepsy was associated with young-onset dementia.
Why it matters
For dementia developing before age 65, the findings support considering epilepsy when assessing risk, as the authors suggested.
Caveats
These observational studies cannot show that epilepsy caused dementia. The cohort findings concern adults aged 30–55 at entry and do not necessarily apply to other ages.
