title: Changes in prevalence of precancerous oral submucous fibrosis from 1996 to 2013 in Taiwan: A nationwide population-based retrospective study.
abstract: OBJECTIVE
  Oral submucous fibrosis (OSF) has been regarded as a precancerous condition. Research examining the prevalence of OSF could be the first step in preventing or reducing malignant transformation. In this study, we probed a nationwide registered database to assess the prevalence, gender distribution, age, income, and urbanization status of OSF patients in Taiwan.
  
  
  METHODS
  A retrospective study was conducted to analyze the registered database compiled by the National Health Insurance provided by the Ministry of Health and Welfare, Taiwan. We identified dental visit patients diagnosed with OSF during the period between January 1, 1996 and December 31, 2013. In addition, demographic characteristics were analyzed by multivariate Poisson regression.
  
  
  RESULTS
  The prevalence of OSF increased significantly from 8.3 (per 105) in 1996 to 16.2 (per 105) in 2013 (p < 0.0001). Men had a significantly higher OSF prevalence than women (p < 0.001). The mean age of patients with OSF increased from 1996 to 2013. Individuals living in rural areas had a higher risk of OSF compared with those living in urban areas [relative risk (RR), 1.10; 95% confidence interval (CI), 1.07-1.13]. The higher income group had a lower risk of OSF compared with the lower income group (RR, 0.76; 95% CI, 0.73-0.80).
  
  
  CONCLUSIONS
  This large-scale government-centered survey demonstrates that the prevalence of OSF in Taiwan significantly increased from 1996 to 2013. The prevalence was higher among men than among women.
authors.affiliation: Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan; Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan.
authors.forename: Shun-Fa
authors.initials: SF
authors.lastname: Yang
authors.affiliation: Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan.
authors.forename: Yu-Hsun
authors.initials: YH
authors.lastname: Wang
authors.affiliation: Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan.
authors.forename: Ni-Yu
authors.initials: NY
authors.lastname: Su
authors.affiliation: School of Dentistry, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: Hui-Chieh
authors.initials: HC
authors.lastname: Yu
authors.affiliation: School of Dentistry, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: Chia-Yi
authors.initials: CY
authors.lastname: Wei
authors.affiliation: School of Dentistry, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: Chuan-Hang
authors.initials: CH
authors.lastname: Yu
authors.affiliation: Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan; School of Dentistry, Chung Shan Medical University, Taichung, Taiwan. Electronic address: cyc@csmu.edu.tw.
authors.forename: Yu-Chao
authors.initials: YC
authors.lastname: Chang
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009313:National Health Programs; D009914:Oral Submucous Fibrosis / Q000453:epidemiology*; D011230:Precancerous Conditions / Q000453:epidemiology*; D015995:Prevalence; D012044:Regression Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D013624:Taiwan / Q000453:epidemiology; D055815:Young Adult
keywords: National Health Insurance; Taiwan; nationwide population; oral submucous fibrosis; prevalence