title: Seasonal patterns of birth in patients with glioblastoma.
abstract: Seasonal distribution of birth rates was only recently described in patients with high-grade gliomas. We analyzed 501 cases from the database of a Regional Cancer Center in Bavaria to assess annual periodicity in the birth dates of glioma patients. Prior to analysis, the number of births per month was normalized [number of births x 100,000/total number of births in Germany] to obtain birth rates per month. The approximation of the time series data by a one-year cosine model found that the glioblastoma birth rate exhibits a statistically significant annual variation, with the peak rate in January. Vitamin intake, infections, and other as-yet-unknown factors and exposures during pre- and perinatal early life may contribute to the seasonality of birth rate in patients with brain tumors.
authors.affiliation: Department of Neurology, University of Regensburg, Universitätsstrasse 84, 93053 Regensburg, Germany.
authors.forename: H J
authors.initials: HJ
authors.lastname: Koch
authors.forename: M
authors.initials: M
authors.lastname: Klinkhammer-Schalke
authors.forename: F
authors.initials: F
authors.lastname: Hofstädter
authors.forename: U
authors.initials: U
authors.lastname: Bogdahn
authors.forename: P
authors.initials: P
authors.lastname: Hau
mesh_terms: D001723:Birth Rate; D002940:Circadian Rhythm; D005260:Female; D005858:Germany / Q000453:epidemiology; D005909:Glioblastoma / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012621:Seasons