title: Epidemiology and extracutaneous comorbidities of severe acne in adolescence: a U.S. population-based study.
abstract: BACKGROUND
  Little is known about the epidemiology of severe acne in the U.S.
  
  
  OBJECTIVE
  We sought to study the U.S. prevalence, determinants and comorbidities of severe acne in adolescence.
  
  
  METHODS
  We analysed data from the 2007 National Health Interview Survey, a cross-sectional questionnaire-based study of 9417 children ages 0-17 years. Prevalence of severe acne, demographics and comorbid disorders were determined.
  
  
  RESULTS
  The U.S. prevalence of severe acne was virtually nil in the first decade of life, but increased in a linear fashion from 11 years [1·7% (95% confidence interval (CI) 0·4-3·0%)] to 17 years of age [12·1% (95% CI 7·8-16·5%)] (Rao-Scott Chi-square, P < 0·0001). Severe acne was more common in Whites compared with other racial groups at age 14-15 years (P = 0·0004) and girls at age 11-13 (P = 0·02). Severe acne was associated with a number of comorbid disorders. Sinopulmonary disease included sinus infection (P = 0·0003), sore throat other than strep infection (P = 0·0003), asthma (P = 0·03) and nonasthmatic lung disease (P = 0·03). Upper gastrointestinal comorbidities included reflux/heartburn (P = 0·0003), abdominal pain (P = 0·03), nausea/vomiting (P = 0·0001) and food/digestive allergy (P = 0·01). Psychological comorbidities included depression (P = 0·02), anxiety (P < 0·0001), attention deficit disorder/attention deficit hyperactivity disorder (P = 0·01) and insomnia (P = 0·02).
  
  
  CONCLUSIONS
  In conclusion, severe acne was more prevalent in older age, Whites, female sex and higher socioeconomic status. Future studies are needed to confirm the associations with sinopulmonary, upper gastrointestinal and psychological disorders in adolescents.
authors.affiliation: Department of Dermatology, Northwestern University, Suite 1400, 680 Lakeshore Drive, Chicago, IL, 60611, U.S.A.
authors.forename: J I
authors.initials: JI
authors.lastname: Silverberg
authors.forename: N B
authors.initials: NB
authors.lastname: Silverberg
mesh_terms: D000152:Acne Vulgaris / Q000150:complications / Q000453:epidemiology*; D000293:Adolescent; D000367:Age Factors; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D005767:Gastrointestinal Diseases / Q000150:complications / Q000453:epidemiology; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000150:complications / Q000453:epidemiology; D015995:Prevalence; D012140:Respiratory Tract Diseases / Q000150:complications / Q000453:epidemiology; D012737:Sex Factors; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology