Seizures Do Not Increase In-Hospital Mortality After Intracerebral Hemorrhage in the Nationwide Inpatient Sample

Background

Seizures are common after intracerebral hemorrhage (ICH) but their impact on outcome is uncertain and prophylactic anti-convulsant use is controversial. We hypothesized that seizures would not increase the risk of in-hospital mortality in a large administrative database.

Methods

The study population included patients in the 2006 Nationwide Inpatient Sample over the age of 18 with a principal diagnosis of ICH (ICD9 = 431). Subjects with a secondary diagnosis of aneurysm, arterio-venous malformation, brain tumor, or traumatic brain injury were excluded. Seizures were defined by ICD9 codes (345.0x–345.5x, 345.7x–345.9x, 780.39). Logistic regression was used to quantify the relationship between seizures and in-hospital mortality. Pre-specified subgroups included age strata, length of stay, and invasive procedures.

Results

13,033 subjects met all eligibility criteria, of which 1,430 (11.0 %) had a secondary diagnosis of seizure. Subjects with seizure were younger (64 vs. 70 years, p < 0.001), more likely to get craniectomy (2.1 vs. 1.2 %, p = 0.006), ventriculostomy (8.5 vs. 6.0 %, p < 0.001), intubation (32.2 vs. 25.9 %, p < 0.001), and tracheostomy (6.4 vs. 4.2 %, p < 0.001). Seizure patients had lower in-hospital mortality (24.3 vs. 28.0 %, p = 0.003). In a multivariable model incorporating patient and hospital level variables, seizures were associated with reduced odds of in-hospital death (OR = 0.62, 95 % CI 0.52–0.75).

Conclusions

A secondary diagnosis of seizure after ICH was not associated with increased in-hospital death overall or in any of the pre-specified subgroups; however, there may be residual confounding by severity. These findings do not support a need for routine prophylactic anti-epileptic drug use after ICH.