LOS ANGELES — New research suggests that a large portion of stroke patients develop seizures and that the long-term risk for seizure after stroke is higher than after traumatic brain injury (TBI).
“As compared to TBI, a disease well known to predispose patients to having seizures, patients with stroke were significantly more likely to develop seizures,” Alexander E. Merkler, MD, study investigator from the Weill Cornell Medical Center, New York, told Neurology Advisor. “This result was surprising to us as TBI has for such a long time been used [as] a disease model to study seizures.”
In the study, which was presented at the 2016 International Stroke Conference, Dr Merkler and colleagues aimed to better understand the long-term risk for seizures after stroke, postulating that it would be similar to the rate observed in patients with TBI.
“Patients with stroke often ask about what type of problems they may expect in the future. As neurologists, we often warn our patients about the risk for recurrent stroke, infections, clots, eating difficulty, and depression,” Dr Merkler said. “Although seizures are a known complication of stroke, there was little data regarding the actual percentage of patients with stroke who develop seizures. Therefore, we sought to evaluate the long-term risk of seizures following stroke to better advise physicians and patients on the likelihood of developing seizures after suffering a stroke.”
The researchers utilized administrative claims data on all acute care hospitalizations and emergency department (ED) visits at nonfederal facilities in California, Florida, and New York between 2005 and 2012. They determined the patients who experienced a first documented stroke and compared them to a control group of patients who had a first documented TBI.
Stroke types included ischemic stroke, intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH).
An ED visit or hospitalization with a discharge diagnosis of seizure served as the primary outcome measure.
The study population included 568,659 patients with stroke and 270,796 patients with TBI.
During follow-up (2.5 ± 2.1 years), patients with stroke had a cumulative risk for seizure of 37.6% (95% confidence interval [CI], 37.3-37.8) compared with 29.9% (95% CI, 29.5-30) in patients with TBI. This resulted in a higher hazard for seizure in the stroke group after adjustment for demographic characteristics and comorbidities (hazard ratio=1.12; 95% CI, 1.11-1.13).
A sensitivity analysis, which limited the outcome to primary discharge diagnoses of seizure or diagnoses of status epilepticus, yielded similar findings.
In other data, the cumulative rates of any seizure were reported in the following subgroups: after SAH, 26.2% (95% CI, 25.6-26.9); after ischemic stroke, 33.6% (95% CI, 33.4-33.7); and after ICH, 35% (95% CI, 34.5-35.4).
“Patients who suffer from a stroke have a significant risk of developing seizures. In particular, patients with hemorrhagic stroke have a significant chance of developing seizures,” Dr Merkler concluded. “The rate of seizures after stroke is higher than the rate of seizures after TBI.”
Dr Merkler noted that both patients and physicians should be aware of the high long-term risk of seizures after stroke.
For more coverage of ISC 2016, go here.
Merkler AE, Dunn LE, Lerario MP, et al. Abstract 109. The Long-Term Risk of Seizures after Stroke. Presented at: International Stroke Conference; Feb. 16-19, 2016; Los Angeles.