title: An observational cross-sectional survey of rosacea: clinical associations and progression between subtypes.
abstract: BACKGROUND
  Few studies have evaluated differences between rosacea subtypes in epidemiological associations and clinical features. The natural history of rosacea is unknown and progression between subtypes has been implied but not formally evaluated.
  
  
  OBJECTIVE
  To assess associations between the four rosacea subtypes [erythematotelangiectatic (ETR), papulopustular (PPR), phymatous (PHY) and ocular], including quantitative and qualitative details on primary and secondary features of rosacea. A secondary objective was to evaluate for the potential of progression between subtypes.
  
  
  METHODS
  This cross-sectional study recruited subjects with rosacea from Northern Germany and comprised clinical evaluation by a dermatologist and a survey of demographics and onset of rosacea-associated signs and symptoms.
  
  
  RESULTS
  A total of 135 subjects with rosacea were enrolled. PHY was more frequently associated with PPR than ETR (P < 0·001). Compared with ETR, PPR was significantly associated with facial burning/stinging (P = 0·001), phymas (P < 0·001) and oedema (P < 0·001); and during flushing episodes, was more frequently associated with burning (P = 0·018), skin tension (P = 0·005) and itching (P = 0·027). ETR was more frequently associated with dry facial skin (P < 0·001). Flushing was reported by 66% and the site most frequently involved was the cheeks (100%). Papulopustules were evanescent in 42% and the sites most frequently involved were the cheeks (80%) and nose (67%). Of those fulfilling criteria for at least two subtypes, 66% developed ETR before PPR; 92% developed ETR before PHY; 83% developed PPR before PHY; and the majority developed cutaneous rosacea-associated features before ocular signs/symptoms.
  
  
  CONCLUSIONS
  Significant differences exist between ETR and PPR in rosacea-associated features and in subtype associations. A small proportion of subjects with rosacea may progress between subtypes.
authors.affiliation: Department of Medicine, University of Western Ontario, 1151 Richmond St, London, Ontario, N6A 3K6, Canada; Windsor Clinical Research Inc., 2224 Walker Road, Suite 300B, Windsor, Ontario, N8W5L7, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Tan
authors.forename: U
authors.initials: U
authors.lastname: Blume-Peytavi
authors.forename: J P
authors.initials: JP
authors.lastname: Ortonne
authors.forename: K
authors.initials: K
authors.lastname: Wilhelm
authors.forename: L
authors.initials: L
authors.lastname: Marticou
authors.forename: E
authors.initials: E
authors.lastname: Baltas
authors.forename: M
authors.initials: M
authors.lastname: Rivier
authors.forename: L
authors.initials: L
authors.lastname: Petit
authors.forename: P
authors.initials: P
authors.lastname: Martel
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012393:Rosacea / Q000145:classification* / Q000150:complications / Q000473:pathology; D011795:Surveys and Questionnaires; D055815:Young Adult