title: Rosacea is associated with chronic systemic diseases in a skin severity-dependent manner: results of a case-control study.
abstract: BACKGROUND
  Rosacea is a common chronic inflammatory dermatosis of unclear origin. It has been associated with systemic comorbidities, but methodical studies addressing this association are lacking.
  
  
  OBJECTIVE
  We evaluated: (1) the association between rosacea and systemic comorbidities; and (2) if the severity of rosacea is impacted by comorbidities.
  
  
  METHODS
  This was a case-control study: patients with rosacea were matched (1:1) to rosacea-free control subjects by age, sex, and race. Relative risk estimates were calculated using logistic regression as odds ratios with 95% confidence intervals.
  
  
  RESULTS
  Among 130 participants (65 patients/65 control subjects), we observed a significant association between rosacea and allergies (airborne, food), respiratory diseases, gastroesophageal reflux disease, other gastrointestinal diseases, hypertension, metabolic and urogenital diseases, and female hormone imbalance. Compared with mild rosacea, moderate to severe rosacea was significantly associated with hyperlipidemia, hypertension, metabolic diseases, cardiovascular diseases, and gastroesophageal reflux disease.
  
  
  CONCLUSIONS
  This was a case-control study with moderate sample size. Associated medical conditions were self-reported and could not always be confirmed by medication use and medical records.
  
  
  CONCLUSIONS
  Rosacea is associated with numerous systemic comorbid diseases in a skin severity-dependent manner. Physicians should be aware of these associations to provide comprehensive care to patients with rosacea, especially to those with more severe disease.
authors.affiliation: Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland. Electronic address: bm.rainer@gmail.com.
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Rainer
authors.affiliation: Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Alexander H
authors.initials: AH
authors.lastname: Fischer
authors.affiliation: Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Dimitre
authors.initials: D
authors.lastname: Luz Felipe da Silva
authors.affiliation: Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Sewon
authors.initials: S
authors.lastname: Kang
authors.affiliation: Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Anna L
authors.initials: AL
authors.lastname: Chien
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000453:epidemiology; D016022:Case-Control Studies; D015897:Comorbidity; D016001:Confidence Intervals; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D006949:Hyperlipidemias / Q000175:diagnosis / Q000453:epidemiology; D006973:Hypertension / Q000175:diagnosis / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008659:Metabolic Diseases / Q000175:diagnosis / Q000453:epidemiology; D008875:Middle Aged; D016017:Odds Ratio; D011379:Prognosis; D018570:Risk Assessment; D012393:Rosacea / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D012720:Severity of Illness Index; D012737:Sex Factors; D016896:Treatment Outcome; D055815:Young Adult
keywords: case-control study; comorbidity; rosacea; severity; systemic disease