Background and objectives: Previous research has demonstrated increased brain amyloid plaque load in individuals with childhood-onset epilepsy in late middle age. However, the trajectory of this process is not yet known. The aim of this study was to determine whether individuals with a history of childhood-onset epilepsy show progressive brain aging in amyloid accumulation in late adulthood (Turku Adult Childhood-Onset Epilepsy study, TACOE).

Methods: Adults from a prospective population-based cohort of individuals with childhood-onset epilepsy, originally recruited 1961-1964, together with matched controls, were scanned with [¹¹C]PIB PET twice: after at least 50 years (TACOE-50) and again after at least 55 years (TACOE-55) from the diagnosis.

Results: At TACOE-55, 31.4% (11/36, mean age 63.3 years, 52.8% female) of individuals from the epilepsy group and 11.4% (4/35, 63.1 year, 54.3%) of controls had a visually abnormal [¹¹C]PIB scan (p = 0.039). At TACOE-55, cortical brain [¹¹C]PIB uptakes were higher and increased more from TACOE-50 in the epilepsy compared with the control group (p < 0.05). In voxelwise whole-brain analyses, the epilepsy group showed significantly higher and more widespread brain amyloid accumulation (p_FWE < 0.05).

Discussion: The results demonstrate that childhood-onset epilepsy is associated with an earlier age at onset of amyloidosis and greater progressive amyloid accumulation in late adulthood.