The hidden link between late‐onset seizures and cerebral amyloid angiopathy: A case–control study

Objective Epileptic seizures occurring in late adulthood often remain of unknown origin. Sporadic cerebral amyloid angiopathy (CAA) is a cerebral small vessel disease characterized by intracerebral hemorrhage, microhemorrhage and superficial siderosis, occurring mostly in elderly. This observational case–control study aimed to assess the occurrence of CAA in patients experiencing their first seizure in late adulthood. Methods We enrolled consecutive patients aged ≥55 years presenting with late‐onset seizures (LOS) to the emergency departments or outpatient clinics of two Italian centers, from April 2021 to October 2022. Two age‐matched control subjects with neurological symptoms other than epileptic seizure were recruited for each enrolled case. All participants underwent brain MRI (1.5 Tesla) including blood‐sensitive sequences and were assessed for probable CAA diagnosis according to Boston criteria 2.0. Chi‐squared test was performed to evaluate group differences. Univariate logistic regression analysis tested the association between clinical variables and CAA. Results We included 65 patients with LOS (27 females; mean age 72.2 ± 8.9 years) and 130 controls (49 females; mean age 70.3 ± 8.9 years). Diagnosis of probable CAA was achieved in 10.8% (7/65) of LOS patients and 2.3% (3/130) controls, with a statistically significant difference (p = 0.011). The OR for CAA in the LOS group was 5.2 as compared to the control group (95% CI = 1.3–20.6, p = 0.02). Significance The frequency of CAA is significatively higher in patients with LOS as compared to other neurological diseases, suggesting that a portion of LOS of unknown or vascular origin are associated with CAA. Plain Language Summary Late‐onset seizures (LOS) are very frequent in the elderly and often have no clear cause. Cerebral amyloid angiopathy (CAA) is a condition where amyloid proteins build up in the blood vessels of the brain, causing them to become weak and prone to bleeding. In this study, we explored the occurrence of CAA in people with LOS. We found that people with LOS were more likely to have a diagnosis of CAA than controls (i.e., people with other neurological diseases).