title: Corrective eyeglasses and medial canthal basal cell carcinoma: a case-control study.
abstract: BACKGROUND
  Corrective eyeglasses are frequently worn by adults, particularly at older ages. Their lenses and frames provide ultraviolet protection. Medial canthal basal cell carcinomas are infrequent (3-8%), and their relation with the use of corrective glasses was not yet investigated.
  
  
  OBJECTIVE
  To assess the prevalence of corrective eyeglasses use in individuals with medial canthal basal cell carcinoma.
  
  
  METHODS
  Case-control study using two controls matched by age, gender, and ethnicity for each case. Cases were patients with medial canthal basal cell carcinoma, and controls were patients with basal cell carcinoma elsewhere on the face. The prevalence of major risk variables was estimated and adjusted by conditional multiple logistic regression.
  
  
  RESULTS
  Fifty cases and 100 controls were assessed. The mean patient age was 69.7 years, and 54% of the subjects were females. No difference regarding the eyeglasses use or use duration was found between groups. However, when visual defects were separately evaluated, eyeglasses for myopia correction were independently associated with lower risk of medial canthal basal cell carcinoma development (OR=0.26; P=0.03), what can be related to long term local photoprotection.
  
  
  CONCLUSIONS
  The use of eyeglasses for myopia correction is associated with lower prevalence of medial cantal basal cell carcinoma. Risk-reducing mechanisms should be elucidated.
authors.affiliation: Departamento de Dermatologia, Faculdade de Medicina de Botucatu, UNESP-Univ Estadual Paulista, Botucatu-SP-Brazil.
authors.forename: M
authors.initials: M
authors.lastname: Resende
authors.forename: A C
authors.initials: AC
authors.lastname: Hercos
authors.forename: H A
authors.initials: HA
authors.lastname: Miot
mesh_terms: D000368:Aged; D001938:Brazil / Q000453:epidemiology; D002280:Basal Cell Carcinoma / Q000453:epidemiology*; D016022:Case-Control Studies; D005139:Eyeglasses; D005145:Face; D005260:Female; D006801:Humans; D008297:Male; D012878:Skin Neoplasms / Q000453:epidemiology*