title: Factors in contact lens symptoms: evidence from a multistudy database.
abstract: OBJECTIVE
  This study aimed to examine the effects of demographic, lens performance, and ocular surface response measures on contact lens-related discomfort and dryness, using a large contact lens study database.
  
  
  METHODS
  A total of 4164 records were extracted from a database of 220 subjects participating in 46 silicone hydrogel contact lens studies. Subjects discontinued lens wear for 24 hours and were then fit with either comfilcon A or enfilcon A lenses. The fit and performance of the lenses, along with subjective comfort and dryness, were assessed on insertion and after 3 and 6 hours of wear. After 6 hours of wear, ocular surface health was also assessed by fluorescein slitlamp examination.
  
  
  RESULTS
  Decreased comfort at 3 hours after insertion was associated with excessive lens movement (p < 0.001), front surface deposits (p = 0.004), poor wettability (p = 0.014), and Asian ethnicity (p < 0.001). After 6 hours of wear, decreased comfort remained associated with greater lens movement (p = 0.032) and Asian ethnicity (p < 0.001), along with inferior corneal staining (p < 0.001). Dryness after 3 hours of wear was associated with greater lens movement (p < 0.001), Asian ethnicity (p < 0.001), increased deposits (p < 0.001), and poor wettability (p < 0.001). Dryness after 6 hours of wear remained associated with greater lens movement (p < 0.001) and Asian ethnicity (p < 0.001), along with inferior corneal staining (p < 0.001) and inferior lens decentration (p = 0.001).
  
  
  CONCLUSIONS
  Excessive lens movement, inferior lens decentration, poor surface wettability and deposits, inferior corneal staining, and Asian ethnicity are associated with discomfort and dryness. Clinicians should consider all these factors to achieve the most comfortable and successful contact lens fit.
authors: *OD, MPH †MA ‡OD, PhD, FAAO Clinical Research Center, School of Optometry, University of California, Berkeley, Berkeley, California (all authors).
authors: Tan N
authors: TN
authors: Truong
authors: Andrew D
authors: AD
authors: Graham
authors: Meng C
authors: MC
authors: Lin
mesh_terms: D000293:Adolescent; D000328:Adult; D003263:Contact Lenses, Hydrophilic / Q000009:adverse effects*; D016208:Databases, Factual; D015352:Dry Eye Syndromes / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D008297:Male; D017060:Patient Satisfaction; D017755:Prosthesis Fitting; D012828:Silicones; D013997:Time Factors; D014786:Vision Disorders / Q000209:etiology* / Q000503:physiopathology; D014785:Vision, Ocular / Q000502:physiology; D055815:Young Adult
chemical_list: D012828:Silicones; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate