Abstracts

Rationale: Hemoglobin A1c (HbA1c) is a test that reflects the average extracellular glucose concentrations present in a two to three month timespan. Elevated HbA1c signifies poor blood glucose control. Hyperglycemic conditions are known to promote epileptiform activity and are also associated with poorer outcomes in acute stroke patients.^1,2 There is limited research on elevated HbA1c and its effect on seizure control in patients with epilepsy. We hypothesize that elevated HbA1c could play a role in the effectiveness of AEDs, leading to an increase in the number of AEDs required to control seizures in epileptic patients. Patients who fail to respond to at least two indicated and tolerated AEDs have worse outcomes in managing their epilepsy.  The study aims to investigate whether better control of HbA1c levels in epileptic patients could lead to fewer refractory cases and better patient outcomes.

Methods: In this retrospective study, we reviewed records from 480 patients aged 18 and older with epilepsy and HbA1c levels obtained on admission to the epilepsy monitoring unit (EMU). The dataset includes patients admitted between 2016-2019 to the EMU at INOVA Fairfax Hospital in Virginia. The number of AEDs vs. HbA1c level were analyzed for each patient using ANOVA and Chi-square.  An age-match analysis was also performed as a separate comparison variable.

Results: Of the 480 patients, 89 had a HbA1c in the diabetes range ( >6.5%), 93 were in the pre-diabetes range (5.7%-6.4%), and 298 were in the normal range (≤5.6%). The analysis was performed on two groups. The first group included patients with one AED prescribed for seizure control vs. the second group, which included patients prescribed 2 or more AEDs for seizure control. For this study, we categorized patients taking more than >1 AED as poor seizure control and this group may also include possible refractory epilepsy patients. After the EMU study 7% (N=34) of participants were not confirmed with a diagnosis of epilepsy and this population was excluded from the analysis. 45% (N=216) of participants had 1 AED prescribed, and 48% (N=230) of participants required 2 or more AEDs. The average HbA1c in the 1 AED group was 5.9 ± 1.3 vs. the 2 or more AED group with an average HbA1c of 5.8 ± 1.5 (p-value=0.5640). In comparing the age vs. AED number, the 1 AED group had an average age of 51.7 ± 18.6 vs. the two or more AED group with an average age of 49.5 ± 17.3 (p-value=0.1861).

Conclusions: Strict sugar control in epileptic patients could have a positive outcome similar to patients with acute stroke. We hypothesized that patients with elevated HbA1c are more likely to require a higher number of AEDs for seizure control. The results showed that the average HbA1c in the group with 1 AED vs. the group with 2 or more AEDs was similar, not be statistically significant (p=0.5640). It also did not show a significant association between age and corresponding number of AEDs (p=0.1861). As a retrospective study, other non-controllable factors could have impacted the results. We are designing a future prospective study with more controlled parameters and less associated bias.

Funding: None