title: Prevalence of the chronic sinusitis diagnosis in Olmsted County, Minnesota.
abstract: BACKGROUND
  Commonly cited estimates from the National Health Interview Survey rank chronic sinusitis as one of the most prevalent chronic diseases in the United States. These data rely on patient self-reporting of the disease. However, chronic sinusitis is difficult to diagnose because its symptoms overlap those of many other disease processes. As such, these prevalence data may be unreliable.
  
  
  OBJECTIVE
  To provide an estimate of the prevalence of chronic sinusitis based on assigned International Classification of Diseases, Ninth Revision (ICD-9) codes for the year 2000 in a population-based sample. This study establishes the individual patient as the unit of measure vs previous ICD-9-based estimates that measured physician encounters.
  
  
  METHODS
  Using existing databases, we identified all residents of Olmsted County, Minnesota, who were assigned an ICD-9 diagnosis code for chronic sinusitis (473.x) in the year 2000.
  
  
  METHODS
  Primary care and referral center serving the general community.
  
  
  METHODS
  All residents of Olmsted County who provided research authorization were eligible.
  
  
  METHODS
  Age- and sex-specific prevalence of chronic sinusitis based on assigned ICD-9 diagnosis codes.
  
  
  RESULTS
  In the year 2000, 2405 residents of Olmsted County were given an ICD-9 diagnosis code for chronic sinusitis. Among these, 1627 (67.7%) were female and 778 (32.3%) were male. The overall age- and sex-adjusted prevalence per 100,000 was 1955 (1.96%). The mean (SD) age at the time of diagnosis was 39.4 (17.6) years (age range, 4.2 months to 94 years). Eighty-seven percent were diagnosed at Mayo Clinic, and the balance were from the Olmsted Medical Center. At Mayo, family practitioners and internists diagnosed most of the cases (70%); only 8% were diagnosed by the Department of Otolaryngology. The diagnosis code 473.9 for unspecified chronic sinusitis made up 95% of cases.
  
  
  CONCLUSIONS
  Current prevalence estimates of chronic sinusitis may be exaggerated. Chronic sinusitis has been reported to affect 14% to 16% of the US population according to a National Health Interview Survey. In Olmsted County, we found a much lower prevalence (1.96%) of chronic sinusitis using ICD-9 codes as an identifier.
authors.affiliation: Department of Otolaryngology, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Ron G
authors.initials: RG
authors.lastname: Shashy
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Moore
authors.forename: Amy
authors.initials: A
authors.lastname: Weaver
mesh_terms: D000328:Adult; D002908:Chronic Disease; D016208:Databases, Factual / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D038801:International Classification of Diseases; D008297:Male; D008910:Minnesota / Q000453:epidemiology; D015995:Prevalence; D012852:Sinusitis / Q000145:classification / Q000453:epidemiology*