Seizure Risk After Sepsis Lasts for Years

— Far above rates seen in non-sepsis patients, especially at younger ages

MedicalToday

BOSTON -- Sepsis survivors continue to experience elevated rates of seizures long after discharge compared with other patients with histories of hospitalization, a researcher said here.

Analysis of some 850,000 discharges in three large states, with up to 8 years of follow-up, showed that individuals with sepsis had a five-fold increase in risk of seizures following discharge (HR 4.98, 95% CI 4.92-5.04), compared with a similarly-sized cohort of hospital patients without records of sepsis, reported Michael Reznik, MD, of Weill Cornell Medicine/Columbia University Medical Center in New York City.

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  • Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.

The increase in risk was confirmed in an analysis of Medicare records for individuals 65 and older, Reznik said during a platform session at the American Academy of Neurology annual meeting; the increased risk associated with previous sepsis in this age group was somewhat but still significant (incidence rate ratio 2.72, 95% CI 2.60-2.83).

Very similar results were found in the first dataset when stratified by age, Reznik added. This post-hoc analysis showed that, among individuals younger than 65, the risk increase was correspondingly greater, with an IRR of 10.33 (95% CI 10.17-10.49).

He emphasized that the absolute risk in older individuals was considerably higher than in younger people, presumably because the 65-plus age group has a greater burden of seizure risk factors.

Reznik began his presentation by explaining that an increased short-term risk for seizures was already well established for sepsis patients during their hospitalization for the condition. But the possible persistence of seizure risk had not been well studied, although there has been increasing recognition that sepsis survivors often show cognitive deficits and encephalopathy.

To examine the longer-term risk quantitatively, his group drew on data from the Healthcare Cost and Utilization Project (HCUP), which included detailed administrative claims for hospital discharges in California, New York, and Florida. The researchers focused on patients whose records indicated sepsis diagnostic codes during 2005-2013. They excluded those with previous histories of seizures and those who weren't residents of the three states (the latter to maximize the chances that follow-up hospitalizations would be captured in HCUP data).

For comparison, the researchers developed a cohort of other hospital discharges without sepsis codes in the HCUP data during the same period, matched to the sepsis patients for age, sex, race, insurance, and other factors.

Among the 842,735 discharges with sepsis codes, just over 30,000 had subsequent hospitalizations or emergency department visits for seizures during up to 8 years of follow-up.

The annual incidence of seizure was 1.29% among the sepsis survivors, versus 0.16% in the comparison group.

Reznik showed a Kaplan-Meier curve depicting cumulative seizure rates in the sepsis and comparison groups during follow-up, which demonstrated that sepsis survivors continued to face elevated seizure risk through the study period. The cumulative risks at the 8-year mark were 6.67% among sepsis patients versus 1.27% in controls.

Taken together, the findings along with previous literature point to sepsis as having significant potential to cause brain injury, Reznik said.

Future research should address the specific pathways and risk factors that lead to seizures following sepsis, and whether protective interventions or strategies could be developed, he added.

Reznik also acknowledged several limitations to the analysis: its reliance on administrative records, lack of detail about patients' sepsis episodes, the possible presence of other neuropathologies not noted in charts, and the potential for ascertainment bias (specifically, that recent sepsis patients may be monitored more closely than others and therefore seizures more likely to be noted).

Disclosures

Reznik disclosed no relevant relationships with industry.

Primary Source

American Academy of Neurology

Reznik M, et al "Long-Term Risk of Seizures in Survivors of Sepsis" AAN 2017; Abstract S5.003.