Abstracts

Rationale: As the legal use of medical cannabis expands across the United States, the prevalence of marijuana use in the adult population has doubled over the past decade, reaching 13.3% in 2014. When conventional treatments do not work to control seizures, as is the case for roughly 30% of people with epilepsy (PWE), some turn to various cannabis derived products. Our retrospective record review aimed to survey cannabis use among PWE under the care of a large community-based Comprehensive Epilepsy Center in Honolulu, Hawaii.  Methods: PWE with cannabis usage were identified from a cohort of 1131 patients at the Comprehensive Epilepsy Center, Hawaii Pacific Neurosciences over a four-year period (2014-2018). The patient's demographics such as age, sex, ethnicity, psychological disorders and substance abuse were recorded. Cannabis primary use was categorized as medical or recreational. The patients' seizure type, level of control, and number of anti-epileptic drugs (AED) were recorded. Data was analyzed through descriptive statistics.  Results: Of the patients included in this study (n=1131), 57 (5%) PWE readily admitted use of marijuana/cannabis related products during their clinic visits. 35 (61%) are males and 22 (39%) are females. The mean age is 43 years-old (range of 16-70 years of age). 24 (42%) are Caucasian, 19 (33%) Native Hawaiians/Pacific Islanders, 5 (9%) Asian and 9 (16%) others.Among 57 PWE, 18 (32%) admitted to using cannabidiol (CBD) for medical reasons, 39 (68%) admitted to using recreational marijuana (RM). Seizure control among the 18 PWE-CBD was noted as follows: 7 (39%) with none to one yearly seizure, 3 (17%) with 2 to 12 seizures a year, 6 (33%) with two or more monthly seizures, and 2 (11%) for whom the level of seizure control was not specified. Five are taking three or more AED's. The seizure-type was primarily focal (n=15, 83%). Eight among PWE-CBD users (44%) had a history of a psychiatric disorder; and alcohol abuse was noted in two patients (11%).Of the 39 PWE-RM, 20 (51%) experienced none to one yearly seizure, 5 (13%) with 2 to 12 seizures a year, 9 (23%) with two or more monthly seizures, and 5 (13%) were unspecified. Likewise, their seizure type was primarily focal (n=34, 87%). Only two (5%) are on three or more AEDs. The diagnosis of any psychiatric condition was present in 14 (36%) in PWE-RM and in contrast to PWE-CBD, alcohol abuse was noted in 10 patients (26%).  Conclusions: Surprisingly, the use of cannabinoids among PWE was lower than expected, considering Hawaii legalized medicinal marijuana in 2000. As this is a retrospective chart-review, limitations include the lack of reporting or recording of patients' cannabis use. The trends noted in PWE-CBD are higher seizures and AED burden; while PWE-RM have a higher risk of abusing alcohol. The results support the need to probe deeper into PWE use of cannabinoids with a potential to affect seizure threshold.  Funding: No funding