title: Risks factors for recurrent neurological decompression sickness in recreational divers: a case-control study.
abstract: OBJECTIVE
  Individual or environmental factors that predispose to the recurrence of neurological decompression sickness (DCS) in scuba divers are not known and preventive measures designed to mitigate the risk of a subsequent episode remain empirical. The aim of this controlled study was to examine some potential risk factors predictive of recurrent DCS event that may lead to practical recommendations for divers who wish to continue diving after an initial episode.
  
  
  METHODS
  Age, gender, diving experience, presence of a large right-to-left shunt (RLS) and diving practice following post-DCS resumption were evaluated as potential predictors of a further DCS in recreational divers admitted in our hyperbaric facility over a period of 12 years.
  
  
  RESULTS
  Twenty-four recurrent cases and 50 divers treated for a single DCS episode which continued diving were recruited after review of medical forms and follow-up interview by telephone. After controlling for potential confounding variables between groups, multivariate analysis revealed that experienced divers (OR, 3.8; 95%CI, 1.1-14; P=0.03), the presence of large RLS (OR, 5.4; 95%CI, 1.5-19.7; P=0.006) and the lack of changes in the way of diving after prior DCS (OR, 8.4; 95%CI, 2.3-31.1; P=0.001) were independently associated with a repeated episode.
  
  
  CONCLUSIONS
  The findings highlight the importance for divers to adopt conservative dives profiles or to use preferentially oxygen-enriched breathing mixtures after an initial DCS. Closure of a documented RLS through a large patent foramen ovale as a secondary preventive procedure for individuals that cannot adapt their diving practice remains debatable.
authors.affiliation: Department of Hyperbaric and Diving Medicine, Sainte Anne's Military Hospital, Toulon, France. gempp@voila.fr
authors.forename: E
authors.initials: E
authors.lastname: Gempp
authors.forename: P
authors.initials: P
authors.lastname: Louge
authors.forename: J E
authors.initials: JE
authors.lastname: Blatteau
authors.forename: M
authors.initials: M
authors.lastname: Hugon
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D003665:Decompression Sickness / Q000209:etiology* / Q000628:therapy; D004242:Diving / Q000009:adverse effects*; D005260:Female; D054092:Foramen Ovale, Patent / Q000150:complications / Q000601:surgery; D005602:France / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D011998:Recreation; D012008:Recurrence; D012307:Risk Factors; D018709:Statistics, Nonparametric