Epilepsy in immigrants and Swedish-born: A cohort study of all adults 18 years of age and older in Sweden

Per Wändell; Sten Fredrikson; Axel C Carlsson; Xinjun Li; Danijela Gasevic; Jan Sundquist; Kristina Sundquist

doi:10.1016/j.seizure.2020.02.005

Epilepsy in immigrants and Swedish-born: A cohort study of all adults 18 years of age and older in Sweden

Seizure. 2020 Feb 7:76:116-122. doi: 10.1016/j.seizure.2020.02.005. Online ahead of print.

Authors

Per Wändell¹, Sten Fredrikson², Axel C Carlsson³, Xinjun Li⁴, Danijela Gasevic⁵, Jan Sundquist⁶, Kristina Sundquist⁶

Affiliations

¹ Division of Family Medicine and Primary Care, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden. Electronic address: per.wandell@ki.se.
² Department of Clinical Neuroscience, Division of Neurology, Karolinska Institutet Huddinge, Stockholm, Sweden.
³ Division of Family Medicine and Primary Care, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden; Academic Primary Health Care Centre, Stockholm Region, Stockholm, Sweden.
⁴ Center for Primary Health Care Research, Lund University, Malmö, Sweden.
⁵ Usher Institute of Population Health Sciences and Informatics, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK; School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia.
⁶ Center for Primary Health Care Research, Lund University, Malmö, Sweden; Department of Family Medicine and Community Health, Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Center for Community-based Healthcare Research and Education (CoHRE), Department of Functional Pathology, School of Medicine, Matsue, Shimane University, Japan.

PMID: 32062322
DOI: 10.1016/j.seizure.2020.02.005

Abstract

Purpose: We aimed to study the association between country of birth and incident epilepsy in several immigrant groups using Swedish-born individuals as referents.

Method: The study population included all adults aged 18 years and older in Sweden, living and deceased, 6,690,598 in the first-generation and 6,683,125 in the second-generation sub-study. Epilepsy was defined as having at least one registered diagnosis of epilepsy in the National Patient Register. The incidence of epilepsy in different immigrant groups, using Swedish-born as referents, was assessed by Cox regression, expressed as hazard ratios (HRs) and 95 % confidence intervals (CI). The models were stratified by sex and adjusted for age, geographical residence in Sweden, educational level, marital status, and neighbourhood socioeconomic status.

Results: In the first-generation sub-study, totally 76,541 individuals had at least one registered diagnosis of epilepsy (1.14 % in total; men 1.22 % and women 1.07 %), and in the second-generation study 72,545 (1.09 %; men 1.18 % and women 0.99 %). After adjusting for confounders, in first-generation immigrants compared to their Swedish-born counterparts the incidence was somewhat lower among both men (HR 0.92, 0.90-0.96) and women (HR 0.93, 0.90-0.96), and in the second-generation immigrants among women (HR 0.95, 0.92-0.99) but not men (HR 0.99; 0.96-1.02). Among immigrant groups, a higher incidence of epilepsy was observed among first-generation women from Africa and Iraq, and second-generation men and women from Bosnia, and women from Finland.

Conclusions: Risk of epilepsy was lower in immigrants in general compared to the Swedish-born population; but with higher incidence in some specific groups.

Keywords: Epilepsy; Gender; Immigrants; Neighborhood; Socioeconomic status.