title: Season of birth in valvular heart disease.
abstract: This study demonstrates seasonal variations of birth dates in children with congenital valvular heart disease and in adults dying from valvular heart disease. The findings are based on the 1989-98 Swiss EUROCAT data, and on 1969-94 Swiss mortality records. Seasonality was tested with aggregated monthly data using Edwards' procedure. Both data sets showed excesses between December and March, consistent in different forms of valvular disease and in both sexes. Despite the decline of rheumatic heart disease, risk factors causing season of birth effects remain relevant for congenital anomalies.
authors.affiliation: Institute of Social and Preventive Medicine, University of Zurich, Zurich, Switzerland.
authors.forename: Daniela
authors.initials: D
authors.lastname: Bosshardt
authors.forename: Vladeta
authors.initials: V
authors.lastname: Ajdacic-Gross
authors.forename: Phung
authors.initials: P
authors.lastname: Lang
authors.forename: Mathias
authors.initials: M
authors.lastname: Bosshardt
authors.forename: Matthias
authors.initials: M
authors.lastname: Bopp
authors.forename: Marie-Claude
authors.initials: MC
authors.lastname: Addor
authors.forename: Felix
authors.initials: F
authors.lastname: Gutzwiller
mesh_terms: D000328:Adult; D001021:Aortic Valve / Q000002:abnormalities; D005260:Female; D006349:Heart Valve Diseases / Q000151:congenital* / Q000401:mortality; D006801:Humans; D008297:Male; D008943:Mitral Valve / Q000002:abnormalities; D036801:Parturition; D011664:Pulmonary Valve / Q000002:abnormalities; D012307:Risk Factors; D012621:Seasons; D017678:Sex Distribution; D014261:Tricuspid Valve / Q000002:abnormalities