Clinical profiles and prognostic factors in reflex epilepsy: Insights from a Taiwanese cohort

• Published in: Seizure (London, England) England), 2025-01, Vol.124, p.39-47
• Main Authors: Lin, Chih-Han, Cheng, Mei-Yun, Tseng, Wei-En Johnny, Chang, Chun-Wei, Lee, Chih-Hong, Wu, Tony, Chiang, Hsing-I, Liao, Ting-Wei, Lin, Wey-Ran, Liu, Chun-Jing, Chen, Po-Ru, Lim, Siew-Na
• Format: Article
• Language: English
• Subjects: Mah-Jong; Photosensitive; Reflex epilepsy; Reflex seizures; Seizure outcome; Spontaneous seizures
• ISSN: 1059-1311; 1532-2688; 1532-2688
• DOI: 10.1016/j.seizure.2024.11.013

•Patients with extrinsic reflex epilepsy (RE) had a significantly earlier onset of both spontaneous and reflex seizures compared to those with intrinsic RE.•Avoidance of seizure triggers was more frequent in intrinsic RE and correlated with better seizure control and prognosis.•Patients with extrinsic RE exhibited lower rates of stimulus avoidance, and 98 % of them were treated with ASM, highlighting the difficulty in avoiding environmental stimuli and the essential role of ASM in controlling seizures for these patients. To investigate the clinical characteristics, treatment, and prognosis of patients with reflex epilepsies in Taiwan. Patients with reflex epilepsies (RE) induced by specific trigger factors from July 2000 to May 2024, were recruited at Chang Gung Memorial Hospital, Linkou, Taiwan. All patients had at least 12 months of follow-up. Demographic data, antiseizure medication (ASM) treatment, stimulus avoidance, and seizure outcome were analyzed. We further divided the patients into extrinsic and intrinsic RE groups based on the nature of stimuli. We also categorized them into ongoing seizure and seizure-free groups based on their seizure control. Fisher's exact test and Independent-Samples Mann-Whitney U Test were used to evaluate associations between clinical factors and prognosis. Multivariate logistic regression analysis was further carried out to determine the predictors of seizure outcomes. In this study, 81 patients with reflex epilepsies (RE) were analyzed, focusing on those with extrinsic (photosensitive) and intrinsic (Mah-Jong-related) seizure triggers. Patients with extrinsic RE were significantly younger (mean age 40.4 years) than those with intrinsic RE (mean age 64.4 years, p < 0.001) and had a notably earlier onset of reflex seizures (21.9 years vs. 49.7 years, p < 0.001). A higher proportion of extrinsic RE patients experienced spontaneous seizures (98 %) compared to intrinsic RE (40 %). Abnormal EEG findings were more prevalent in the extrinsic group (94.1 %) than in the intrinsic group (66.7 %). Ninety-eight percent of patients with extrinsic RE were treated with antiseizure medications (ASMs), with an average of 2.2 ASMs per patient, compared to 73.3 % and 1.2 ASMs in patients with intrinsic RE. Furthermore, the rate of stimulus avoidance was significantly higher among those with intrinsic RE, at 43.3 % compared to 3.9 % in the extrinsic group (p < 0.001). Both groups achieved similar seizure-free outcomes (68.6 % in extrinsic