Association of outdoor air and noise pollution with unprovoked seizures and new onset epilepsy: A systematic review and meta-analysis.

Research has indicated that certain environmental exposures may increase the risk of unprovoked seizures and new onset epilepsy. This study aimed to synthesize the literature that has estimated the associations between short- and long-term exposure to outdoor air and noise pollution and the risk of unprovoked seizures and new onset epilepsy. We searched Embase, MEDLINE, Scopus, Web of Science, BIOSIS Previews, Latin American and Caribbean Health Sciences Literature, Proquest Dissertations and Theses, conference abstracts, and the gray literature and conducted citation tracing in June 2023. Observational and ecological studies assessing the associations of air and noise pollution with unprovoked seizures or new onset epilepsy were eligible. One reviewer extracted summary data. Using fixed and random effects models, we calculated the pooled risk ratios (RRs) for the studies assessing the associations between short-term exposure to air pollution and unprovoked seizures. Seventeen studies were included, 16 assessing the association of air pollution with seizures and one with epilepsy. Eight studies were pooled quantitatively. Ozone (O3; RR = .99, 95% confidence interval [CI] = .99-.99) and nitrogen dioxide (NO2) exposure adjusted for particulate matter (RR = 1.02, 95% CI = 1.01-1.02) on the same day, and carbon monoxide (CO) exposure 2 days prior (RR = 1.12, 95% CI = 1.02-1.22), were associated with seizure risk. A single study of air pollution and epilepsy did not report a significant association. The risk of bias and heterogeneity across studies was moderate or high. Short-term exposure to O3, NO2, and CO may affect the risk of seizures; however, the effect estimates for O3 and NO2 were minimal. Additional research should continue to explore these and the associations between outdoor air pollution and epilepsy and between noise pollution and seizures and epilepsy.

Incidence of First-Episode Status Epilepticus and Risk Factors in Ontario, Canada.

BACKGROUND: Status epilepticus (SE) is a neurological emergency characterized by prolonged seizures. However, the incidence of first-episode SE is unclear, as estimates vary greatly among studies. Additionally, SE risk factors have been insufficiently explored. Therefore, the objectives of this study were to estimate the incidence of first-episode SE in Ontario, Canada, and estimate the associations between potential sociodemographic and health-related risk factors and first-episode SE. METHODS: We conducted a population-based retrospective cohort study using linked health administrative datasets. We included individuals who completed Canada's 2006 Census long-form questionnaire, lived in Ontario, were between 18 and 105, and had no history of SE. A Cox proportional hazards regression model was used to estimate the hazard ratios for SE within three years associated with each potential risk factor. RESULTS: The final sample included 1,301,700 participants, 140 of whom were hospitalized or had an emergency department visit for first-episode SE during follow-up (3.5 per 100,000 person-years). Older age was the only significant sociodemographic SE risk factor (HR = 1.35, 95% CI = 1.33, 1.37), while health-related risk factors included alcohol or drug abuse (HR = 1.05, 95% CI = 1.02, 1.08), brain tumour or cancer (HR = 1.14, 95% CI = 1.12, 1.15), chronic kidney disease (HR = 1.32, 95% CI = 1.29, 1.36), dementia (HR = 1.42, 95% CI = 1.36, 1.48), diabetes (HR = 1.11, 95% CI = 1.09, 1.12), epilepsy or seizures (HR = 1.05, 95% CI = 1.01, 1.09) and stroke (HR = 1.08, 95% CI = 1.05, 1.11). CONCLUSION: The estimated incidence of SE in a sample of Ontario residents was 3.5 per 100,000 person-years. Older age and several comorbid conditions were associated with higher first-episode SE risk.

Epilepsy Surgery in Adult Stroke Survivors with New-Onset Drug-Resistant Epilepsy.

BACKGROUND: Despite its effectiveness, surgery for drug-resistant epilepsy is underutilized. However, whether epilepsy surgery is also underutilized among patients with stroke-related drug-resistant epilepsy is unclear. Therefore, our objectives were to estimate the rates of epilepsy surgery assessment and receipt among patients with stroke-related drug-resistant epilepsy and to identify factors associated with these outcomes. METHODS: We used linked health administrative databases to conduct a population-based retrospective cohort study of adult Ontario, Canada residents discharged from an Ontario acute care institution following the treatment of a stroke between January 1, 1997, and December 31, 2020, without prior evidence of seizures. We excluded patients who did not subsequently develop drug-resistant epilepsy and those with other epilepsy risk factors. We estimated the rates of epilepsy surgery assessment and receipt by March 31, 2021. We planned to use Fine-Gray subdistribution hazard models to identify covariates independently associated with our outcomes, controlling for the competing risk of death. RESULTS: We identified 265,081 patients who survived until discharge following inpatient stroke treatment, 1,902 (0.7%) of whom subsequently developed drug-resistant epilepsy (805 women; mean age: 67.0 ± 13.1 years). Fewer than six (≤0.3%) of these patients were assessed for or received epilepsy surgery before the end of follow-up (≤55.5 per 100,000 person-years). Given that few outcomes were identified, we could not proceed with the multivariable analyses. CONCLUSIONS: Patients with stroke-related drug-resistant epilepsy are infrequently considered for epilepsy surgery that could reduce morbidity and mortality.

Epilepsy Risk Following Bariatric Surgery for Weight Loss.

BACKGROUND AND OBJECTIVES: A previous study reported finding that epilepsy risk is elevated after bariatric surgery for weight loss; however, this association has not been adequately explored. Our objectives were to (1) estimate the risk of epilepsy after bariatric surgery for weight loss relative to a nonsurgical cohort of patients with an obesity diagnosis and (2) identify epilepsy risk factors among bariatric surgery recipients. METHODS: We conducted a population-based retrospective cohort study using linked health administrative databases in Ontario, Canada. Participants were accrued between July 1, 2010, and December 31, 2016, and followed until December 31, 2019. All Ontario residents aged 18 years and older who had bariatric surgery during the accrual period were eligible for inclusion in our exposed cohort. Patients hospitalized with a diagnosis of obesity and who did not have bariatric surgery during the accrual period were eligible for inclusion in our unexposed cohort. We excluded patients with a history of seizures, epilepsy, various seizure or epilepsy risk factors, psychiatric disorders, or drug or alcohol abuse/dependence. In our primary analysis, we used inverse probability of treatment weighting to control for confounding. A marginal Cox proportional hazards model was then used to estimate the risk of epilepsy associated with bariatric surgery. A Cox model was also used to identify epilepsy risk factors among exposed participants. RESULTS: The final sample included 16,958 exposed participants and 622,514 unexposed participants. After inverse probability of treatment weighting, the estimated rates of epilepsy were 50.1 and 34.1 per 100,000 person-years among those who did and did not have bariatric surgery, respectively. The hazard ratio for developing epilepsy after bariatric surgery was 1.45 (95% CI = 1.35, 1.56). Among participants who received bariatric surgery, stroke during follow-up increased epilepsy risk (HR = 14.03, 95% CI = 4.26, 46.25). DISCUSSION: In this study, we found that patients with a history of bariatric surgery were at increased risk of developing epilepsy. These findings suggest that epilepsy is a long-term risk associated with bariatric surgery for weight loss.

Depression and suicide after temporal lobe epilepsy surgery: A systematic review.

Psychiatric comorbidities, including depression and suicide, contribute substantially to the illness burden of patients with refractory temporal lobe epilepsy (TLE). The aim of this systematic review was to synthesize the existing literature assessing the effect of TLE surgery on (1) depression prevalence and (2) severity, and estimating the incidence of (3) de novo depression and (4) attempted and completed suicide following TLE surgery. A literature search was performed using Ovid Medline, Embase, Clarivate Web of Science, Cochrane Library, and ProQuest Dissertations and Theses. Studies of patients with TLE who underwent TLE surgery and reported estimates of at least one of the following outcomes were included: pre- and postoperative depression prevalence or severity, the incidence of postoperative de novo depression, or attempted or completed suicide. The search yielded 2,127 citations related to TLE surgery and postoperative depression or suicide. After a full-text review of 98 articles, 18 met the final eligibility criteria. Most studies reported a reduced or similar prevalence (n = 12) and severity of depression (n = 5) postoperatively, compared with the preoperative period. Eleven studies reported the incidence of postoperative de novo depression, which ranged from 0 % to 38 % over follow-up periods of three months to nine years. Four studies assessed the incidence of postoperative attempted or completed suicide, with completed suicide incidence ranging from 0 % to 3 % over follow-up periods of one to four years. Overall, the effect of TLE surgery on depression and suicide remains unclear, as many studies did not assess the statistical significance of depression prevalence or severity changes following TLE surgery. Therefore, timely psychosocial follow-up for patients after TLE surgery should be considered. Future longitudinal studies with consistent measures are needed to elucidate the effect of TLE surgery on the prevalence and severity of depression and estimate the incidence of de novo depression and suicide following surgery.

Epilepsy risk among survivors of intensive care unit hospitalization for sepsis.

OBJECTIVE: To determine whether survivors of intensive care unit (ICU) hospitalizations with sepsis experience higher epilepsy risk than survivors of ICU hospitalizations without sepsis, and to identify sepsis survivors at highest risk. METHODS: We used linked, administrative health care databases to conduct a population-based, retrospective matched cohort study of adult Ontario residents discharged from an ICU between January 1, 2010, and December 31, 2015, identified using the Discharge Abstract Database. We used propensity scores to match patients who experienced sepsis during their index ICU hospitalization with up to 4 patients who did not experience sepsis. We applied marginal Cox proportional hazards regression to estimate the risk of epilepsy within 2 years following the index ICU hospitalization. Among sepsis survivors, Cox proportional hazards regression was used to identify factors associated with epilepsy. RESULTS: A total of 143,892 patients were included, 32,252 (22.4%) of whom were exposed. Sepsis survivors were at significantly higher epilepsy risk (hazard ratio [HR] 1.44, 95% confidence interval [CI] 1.15-1.80). The risk of epilepsy marginally decreased with increasing age (HR 0.97, 95% CI 0.96-0.99); patients with chronic kidney disease (HR 2.25, 95% CI 1.48-3.43) were at highest risk. CONCLUSIONS: In this real-world analysis, sepsis survivors, particularly those who are younger and have chronic kidney disease, are at significantly higher epilepsy risk. These findings indicate that sepsis may be an unrecognized epilepsy risk factor.

The risk of new-onset epilepsy and refractory epilepsy in older adult stroke survivors.

OBJECTIVE: Our study objectives were to identify factors associated with new-onset epilepsy and refractory epilepsy among older adult stroke survivors and to evaluate the receipt of diagnostic care and mortality for participants who developed epilepsy. METHODS: We conducted a population-based, retrospective cohort study using linked, administrative health care databases. The Ontario Stroke Registry was used to identify patients 67 years and older who were hospitalized for a stroke at a designated stroke center in Ontario, Canada, between April 1, 2003, and March 31, 2009, and were previously free of epilepsy. Multivariable Fine-Gray hazard models were used to examine risk factors of epilepsy and refractory epilepsy, accounting for the competing risk of death. RESULTS: Among 19,138 older adults hospitalized for a stroke, 210 (1.1%) developed epilepsy and 27 (12.9%) became refractory to antiepileptic drugs. Within 1 year of epilepsy diagnosis, 24 (11.4%) patients were assessed with EEG and 19 (9.0%) with MRI. In multivariable analysis, younger age and thrombolysis receipt significantly increased epilepsy risk. Lesser stroke severity and anticoagulant medication receipt also significantly increased epilepsy risk; however, these effects decreased over time. Younger age and female sex were the only risk factors of refractory epilepsy. In the 5 years following epilepsy diagnosis, 97 (46.2%) participants died of any cause. CONCLUSIONS: Older adult stroke survivors are less likely to develop epilepsy and pharmacologically refractory epilepsy. An estimated 86.6% of deaths among older adult stroke survivors with new-onset epilepsy are attributed to causes other than stroke or epilepsy.