title: [The role of season in the incidence of deep venous thrombosis].
abstract: BACKGROUND
  The question of the role of season as a predisposing factor for development of venous thromboembolic disease still remains a matter of debate. Actually, most reports described a higher incidence of thrombotic disorders in winter, while a recent study showed no seasonal variation in the incidence of deep vein thrombosis (DVT). These data led us to study the seasonal distribution of all outpatients with DVT admitted to our Department over a period of 14 years.
  
  
  METHODS
  Retrospective review of the files of all outpatients with confirmed (venography or ultrasound) DVT of the legs admitted from Jan. 1st 1982 to Dec. 31st 1995 (n = 512; mean age 59.4 years; 49.4% women).
  
  
  RESULTS
  DVT occurred in spring in 135 (26.4%), in summer in 104 (20.3%), in autumn in 142 (27.7%) and in winter in 131 (25.6%) patients. This distribution appears to be similar to an expected uniform distribution [chi 2(3) df = 6.48; p = 0.090 (NS)].
  
  
  CONCLUSIONS
  In our study, by investigating retrospectively 512 outpatients with confirmed DVT, no correlation was found between season and development of thrombosis, suggesting that cold seasons do not represent a predisposing factor for DVT. Further large prospective studies are needed in order to validate our data and to investigate the clinical implications and the precise role of the season in the risk of occurrence of venous thrombosis.
authors.affiliation: Département de Pathologie Vasculaire, Hôpital Erasme, Université Libre de Bruxelles, Belgique.
authors.forename: C
authors.initials: C
authors.lastname: Galle
authors.forename: J C
authors.initials: JC
authors.lastname: Wautrecht
authors.forename: S
authors.initials: S
authors.lastname: Motte
authors.forename: T
authors.initials: T
authors.lastname: Le Minh
authors.forename: P
authors.initials: P
authors.lastname: Dehon
authors.forename: J
authors.initials: J
authors.lastname: Ferreira
authors.forename: M
authors.initials: M
authors.lastname: Dramaix
authors.forename: J P
authors.initials: JP
authors.lastname: Dereume
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015984:Causality; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012621:Seasons; D013924:Thrombophlebitis / Q000453:epidemiology*
vernacular_title: Rôle de la saison dans l'incidence de la thrombose veineuse profonde.