title: Seasonal variations in the onset and healing rates of venous leg ulcers.
abstract: OBJECTIVE
  As many vascular pathologies exhibit circannual fluctuation, the aim of this study was to assess the chronobiological features of venous ulcers.
  
  
  METHODS
  Based on a retrospective survey of the case histories of 391 venous ulcer patients, the rates of ulcer onset and healing in each month were analysed statistically; a time series was constructed to evaluate the seasonality.
  
  
  RESULTS
  There was a significantly higher frequency of ulcer onset during the warmer part of the year (April-October), and onset showed strong seasonality. Healing rates were also unequally and statistically significantly distributed throughout the year: ulcers that appeared or that were treated with specialized treatment in the winter or summer healed slower in comparison to ulcers that began in the spring or autumn.
  
  
  CONCLUSIONS
  Venous ulcers exhibit circannual fluctuations in their onset and healing rates. Hypothetically, in addition to exacerbation of chronic venous insufficiency, seasonal variations in immune system activity might potentially be responsible for this phenomenon.
authors.affiliation: Department of Angiology, Private Healthcare Institution SANA, Pszczyna, Poland. mariansimka@poczta.onet.pl
authors.forename: M
authors.initials: M
authors.lastname: Simka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002634:Chemotaxis, Leukocyte; D005260:Female; D006358:Hot Temperature; D006801:Humans; D007511:Ischemia / Q000150:complications; D007866:Leg / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D011044:Poland / Q000453:epidemiology; D012189:Retrospective Studies; D012621:Seasons; D014647:Varicose Ulcer / Q000453:epidemiology* / Q000276:immunology / Q000503:physiopathology; D014945:Wound Healing / Q000502:physiology*