Kirstine Juul Christensen1,2, Julie W Dreier1, Line Skotte3, Bjarke Feenstra3, Jakob Grove4,5,6, Anders D Børglum4,5,6, Mitja Mitrovic7, Chris Cotsapas7, Jakob Christensen1,2,8. 1. Department of Economics and Business Economics, National Centre for Register-Based Research, Aarhus BSS, Aarhus University, Aarhus, Denmark. 2. Department of Neurology, Aarhus University Hospital, Aarhus, Denmark. 3. Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark. 4. Department of Biomedicine, Aarhus University, Aarhus, Denmark. 5. The Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH, Aarhus, Denmark. 6. Center for Genomics and Personalized Medicine, Aarhus, Denmark. 7. Department of Neurology, Yale School of Medicine, New Haven, Connecticut, USA. 8. Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
Abstract
INTRODUCTION: Onset of febrile seizures varies with calendar season. However, it has not previously been assessed, how season of birth interacts with age and peak risk of febrile seizures, and whether season of birth correlates with the cumulative risk of febrile seizures at 5 years of age (i.e., when children are no longer of risk of febrile seizures). METHODS: We identified all singleton children born in Denmark between 1977 and 2011 who were alive at 3 months of age (N = 2,103,232). We used the Danish Civil Registration System to identify age and sex of the children and the Danish National Patient Register to identify children hospitalized with febrile seizures from 3 months to 5 years of age. Follow-up ended on December 31, 2016, when all children had reached 5 years of age. RESULTS: The relative risk of admission with a first febrile seizure varied with calendar month; in February (a winter month in Denmark), the risk was more than doubled (hazard ratio: 2.10 [95% confidence interval [CI]: 2.03-2.18]) compared with August (a summer month in Denmark). The age-specific incidence of a first febrile seizure by birth month identified the highest peak incidence of a first febrile seizure among children born in November (reaching a peak incidence of 350 first admissions with a febrile seizure per 100,000 person months at age 16 months) as compared to children born in July (reaching a peak incidence of 200 first admissions with a febrile seizure per 100,000 person months at age 16 months). However, the cumulative incidence of any admission with febrile seizures before 5 years was not correlated with season of birth (3.69% [95% CI: 3.64-3.74%] for winter births, 3.57% [95% CI: 3.52-3.62%] for spring births, 3.55% [95% CI: 3.50-3.59%] for summer births, and 3.64% [95% CI: 3.59-3.69%] for fall births). DISCUSSION/ CONCLUSION: The study found a significant seasonal variation in onset of the first febrile seizure and in the age-specific peak incidence of febrile seizures. However, there was no correlation between season of birth and cumulative incidence of febrile seizures at 5 years of age suggesting that children who are predisposed to febrile seizures will eventually go on to experience a febrile seizure regardless of season of birth.
INTRODUCTION: Onset of febrile seizures varies with calendar season. However, it has not previously been assessed, how season of birth interacts with age and peak risk of febrile seizures, and whether season of birth correlates with the cumulative risk of febrile seizures at 5 years of age (i.e., when children are no longer of risk of febrile seizures). METHODS: We identified all singleton children born in Denmark between 1977 and 2011 who were alive at 3 months of age (N = 2,103,232). We used the Danish Civil Registration System to identify age and sex of the children and the Danish National Patient Register to identify children hospitalized with febrile seizures from 3 months to 5 years of age. Follow-up ended on December 31, 2016, when all children had reached 5 years of age. RESULTS: The relative risk of admission with a first febrile seizure varied with calendar month; in February (a winter month in Denmark), the risk was more than doubled (hazard ratio: 2.10 [95% confidence interval [CI]: 2.03-2.18]) compared with August (a summer month in Denmark). The age-specific incidence of a first febrile seizure by birth month identified the highest peak incidence of a first febrile seizure among children born in November (reaching a peak incidence of 350 first admissions with a febrile seizure per 100,000 person months at age 16 months) as compared to children born in July (reaching a peak incidence of 200 first admissions with a febrile seizure per 100,000 person months at age 16 months). However, the cumulative incidence of any admission with febrile seizures before 5 years was not correlated with season of birth (3.69% [95% CI: 3.64-3.74%] for winter births, 3.57% [95% CI: 3.52-3.62%] for spring births, 3.55% [95% CI: 3.50-3.59%] for summer births, and 3.64% [95% CI: 3.59-3.69%] for fall births). DISCUSSION/ CONCLUSION: The study found a significant seasonal variation in onset of the first febrile seizure and in the age-specific peak incidence of febrile seizures. However, there was no correlation between season of birth and cumulative incidence of febrile seizures at 5 years of age suggesting that children who are predisposed to febrile seizures will eventually go on to experience a febrile seizure regardless of season of birth.
Authors: A T Berg; S Shinnar; A S Darefsky; T R Holford; E D Shapiro; M E Salomon; E F Crain; A W Hauser Journal: Arch Pediatr Adolesc Med Date: 1997-04
Authors: Jakob Christensen; Mogens Vestergaard; Marianne G Pedersen; Carsten B Pedersen; Jørn Olsen; Per Sidenius Journal: Epilepsy Res Date: 2007-08-07 Impact factor: 3.045
Authors: Kirstine J Christensen; Julie W Dreier; Line Skotte; Bjarke Feenstra; Jakob Grove; Anders Børglum; Mitja Mitrovic; Chris Cotsapas; Jakob Christensen Journal: Acta Neurol Scand Date: 2021-04-06 Impact factor: 3.915
Authors: Do Hoon Han; Su Yeong Kim; Na Mi Lee; Dae Yong Yi; Sin Weon Yun; In Seok Lim; Soo Ahn Chae Journal: Seizure Date: 2019-10-18 Impact factor: 3.184