title: [Variables related to the first presbyopia correction].
abstract: OBJECTIVE
  We carried out a prospective study based on variables related to the age of appearance of presbyopia (AAP): refraction defect, sex, iris color, profession and pupil diameter.
  
  
  METHODS
  Our sample population was made up of 179 persons who present consecutively for the first optical correction of presbyopia as sole reason, having a refractive defect equal to 1 diopter or less.
  
  
  RESULTS
  In our series the AAP was not influenced by the small refraction defect, neither by sex or iris color. Different professions showed a significant AAP difference later in life (farmers, x = 51.76 D.E. 5.47 years) or earlier (services workers, x = 46.15 D.E. 3.55 years) (p<0.000003, ANOVA), than other professions such as housewife (48.42 D.E. 4.71 years) and construction workers (47.54 D.E. 3.93 years). We found significant differences in AAP among subjects with intense miosis (<2,5 mm, x = 51 D.E. 5.39 years) and without miosis (3 to 7 mm, x = 47.47 D.E. 4.71 years) (p<0.02 t Student).
  
  
  CONCLUSIONS
  The variables which determine a significant delay in the AAP are: profession (farmer and housewife) and miosis, a 1 mm pupilar diameter reduction, in near vision, could contribute to a delay of 1.53 years in AAP.
authors.affiliation: Servicio de Oftalmología, Hospital Universitario, Granada, España.
authors.forename: J L
authors.initials: JL
authors.lastname: García Serrano
authors.forename: R
authors.initials: R
authors.lastname: López Raya
authors.forename: T
authors.initials: T
authors.lastname: Mylonopoulos Caripidis
mesh_terms: D000328:Adult; D000367:Age Factors; D005127:Eye Color; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009790:Occupations; D011305:Presbyopia / Q000453:epidemiology* / Q000503:physiopathology; D011446:Prospective Studies; D011680:Pupil / Q000502:physiology; D012029:Refraction, Ocular / Q000502:physiology; D012307:Risk Factors; D012737:Sex Factors