There have been concerns that enzyme-inducing antiseizure medications, such as carbamazepine, could interact with drugs used in stroke prevention, possibly resulting in an increased risk of cardiovascular events. The researchers therefore "aimed to investigate if mortality varied with different antiseizure medications. Investigators assessed more than 2500 patients, most in their late seventies, using carbamazepine as a comparator.
Results showed that valproic acid, phenytoin, and oxcarbazepine had a significantly higher risk for all-cause and cardiovascular death compared with carbamazepine, while lamotrigine had a considerably lower risk for both adverse outcomes. Although levetiracetam was associated with a lower risk for cardiovascular death, it showed no significant difference in overall mortality.
The investigators drew on data from four large population-based registers consisting of all adults in Sweden with acute stroke from July 1, 2005, to December 31, 2010, and with subsequent onset of epilepsy prior to December 31, 2015 (n = 2577; 54% male; mean age, 78 years). Among the patients, 82% had experienced an acute ischemic stroke, most (70%) had hypertension, and most (82%) had lived unassisted prior to their stroke. After the stroke, only 44% were able to live unassisted. The researchers chose carbamazepine as the reference medication because it is frequently prescribed and has enzyme-inducing properties.
The research suggests that among antiseizure medications (ASMs) used as monotherapy in poststroke epilepsy (PSE), lamotrigine is associated with the lowest risk for mortality and valproic acid is associated with the highest risk.