title: Risk factors to develop ocular surface disease  in treated glaucoma or ocular hypertension patients.
abstract: OBJECTIVE
  To identify risk factors for developing ocular surface disease (OSD), to verify the prevalence of OSD, and to record efficacy of questionnaires in identifying symptoms' impact on patients' quality of life.
  
  
  METHODS
  . This was an observational, cross-sectional study of patients with topically treated glaucoma. Tear film break-up time (TFBUT) and punctate keratitis were evaluated; 2 quality-of-life questionnaires (National Eye Institute-Visual Function Questionnaire 25 and Glaucoma Symptom Scale) were submitted to all patients. Class of previous and current intraocular pressure (IOP)-lowering drugs, number of drugs, number of drops/day, and total and current benzalkonium chloride (BAK) exposure were collected.
  
  
  RESULTS
  . A total of 233 patients completed the study. TFBUT was abnormal in 71 (30.5%) eyes; punctate keratitis was present in 74 (31.7%). Keratitis was more frequent with increasing number of eyedrops (p=0.008) and number of instillations per day (p=0.009). Ocular surface disease was present in 97 (41.6%) patients and was statistically related to number of medications used (p=0.026). The univariate analysis pointed out that patients with OSD were older (p=0.04), had lower IOP values (p=0.03), were topically treated for more time (p<0.0001), had assumed more BAK (p<0.0001), and presented worst quality of life (p<0.01). The multivariate analysis found that OSD was related to number of medications used (p=0.002), prolonged use of preserved medications (p=0.005), and total BAK exposure (p<0.001).
  
  
  CONCLUSIONS
  There is clinical evidence that the number of medications, their prolonged use, and the total BAK exposure are risk factors to develop OSD in patients with glaucoma. To prevent OSD onset, BAK exposure and the number of topical medications should be reduced.
authors: University Eye Clinic, Fondazione IRCCS Policlinico S. Matteo, Piazzale Golgi 19, Pavia, Italy. gemma.rossi.md@gmail.com
authors: Gemma Caterina Maria
authors: GC
authors: Rossi
authors: Gian Maria
authors: GM
authors: Pasinetti
authors: Luigia
authors: L
authors: Scudeller
authors: Marta
authors: M
authors: Raimondi
authors: Sara
authors: S
authors: Lanteri
authors: Paolo Emilio
authors: PE
authors: Bianchi
mesh_terms: D000368:Aged; D000959:Antihypertensive Agents / Q000009:adverse effects*; D001548:Benzalkonium Compounds / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D005260:Female; D005901:Glaucoma / Q000175:diagnosis / Q000188:drug therapy* / Q000378:metabolism; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D007634:Keratitis / Q000139:chemically induced* / Q000175:diagnosis / Q000378:metabolism; D008297:Male; D009798:Ocular Hypertension / Q000175:diagnosis / Q000188:drug therapy / Q000378:metabolism; D011310:Preservatives, Pharmaceutical / Q000009:adverse effects*; D015995:Prevalence; D011788:Quality of Life; D012307:Risk Factors; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires; D013666:Tears / Q000378:metabolism*; D014065:Tonometry, Ocular
chemical_list: D000959:Antihypertensive Agents; D001548:Benzalkonium Compounds; D011310:Preservatives, Pharmaceutical