Risk of primary childhood brain tumors related to birth characteristics: a Norwegian prospective study.
Relations between birth characteristics and risk of primary brain tumor were explored in a prospective study of the 1,489,297 children born in Norway between 1967 and 1992. A total of 459 primary brain tumors, including 78 medulloblastomas and 168 astrocytomas, were diagnosed in the age interval 0-15 years. The overall risk of brain tumor depended on the season of birth (p = 0.01), with a higher risk for children born in winter than those born in spring [incidence rate ratio (IRR) = 1.52; 95% confidence interval (CI) 1.18-1.97]. An inverse association was observed with father's age at birth of child. The risk of medulloblastoma was positively associated with birth weight (IRR = 1.27/500 g; p = 0.05). Inverse relationships with length at birth were found for astrocytoma in the 0-1 and 5-10 year age intervals. Among 5-10-year-old children, birth weight was also inversely related to risk of astrocytoma. Our results suggest that risk factors may differ over age intervals and histological subgroups.
Section for Medical Statistics, University of Bergen, Norway. Jane.Heuch@smis.uib.no
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Kvåle
D000293:Adolescent; D000367:Age Factors; D001254:Astrocytoma / Q000453:epidemiology* / Q000473:pathology; D001724:Birth Weight; D001932:Brain Neoplasms / Q000453:epidemiology* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008527:Medulloblastoma / Q000453:epidemiology* / Q000473:pathology; D009664:Norway / Q000453:epidemiology; D011446:Prospective Studies; D012307:Risk Factors; D012621:Seasons; D012737:Sex Factors