title: Incidence of and risk factors for glaucoma in lost-to-follow-up normal-tension glaucoma suspect patients.
abstract: BACKGROUND
  To investigate the incidence and risk factors of glaucoma in normal-tension glaucoma (NTG) suspect patients who had been lost-to-follow-up for at least 24 months.
  
  
  METHODS
  Seventy-two eyes of 72 NTG suspect patients who returned to the hospital after at least 24 months of follow-up loss were enrolled in this study between January 2009 and June 2013. The data were collected retrospectively. The incidence of glaucoma was investigated using a comprehensive glaucoma evaluation in lost-to-follow-up NTG suspect patients. The patients were classified into the glaucoma group, who developed glaucoma during the study period, and the glaucoma suspect group, who did not, to analyse the risk factors for glaucoma.
  
  
  RESULTS
  The number of patients who developed glaucoma was 7 (9.7 %) out of the 72 NTG suspect patients who had been mean lost-to-follow-up for 44 months. The rate of progression from suspected to glaucoma was 2.6 %/year. In the glaucoma group, the baseline intraocular pressure (IOP) was 18.43 ± 2.44 mmHg, and the average retinal nerve fiber layer (RNFL) thickness was 78.14 ± 7.60 μm; in the glaucoma suspect group, the baseline IOP was 14.95 ± 2.47 mmHg, and the average RNFL thickness was 92.55 ± 7.65 μm. The study results showed that the glaucoma group had higher baseline IOP and a thinner average RNFL (p = 0.003; p < 0.001). The results of the multivariable logistic regression analysis showed that the risk factors for glaucoma were high baseline IOP (OR = 1.63; p = 0.037) and a thin average RNFL (OR = 0.841; p = 0.004).
  
  
  CONCLUSIONS
  The incidence of glaucoma in the lost-to-follow-up NTG suspect patients was 9.7 % for approximately 44 months, at a rate of 2.6 %/year. The risk factors for glaucoma in these patients were high baseline IOP and a thin average RNFL.
authors.affiliation: 06198 Nune Eye Hospital, #404 Seolleung-ro, Gangnam-gu, Seoul, South Korea.
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Lim
authors.affiliation: 06198 Nune Eye Hospital, #404 Seolleung-ro, Gangnam-gu, Seoul, South Korea.
authors.forename: Jun Sang
authors.initials: JS
authors.lastname: Park
authors.affiliation: 06198 Nune Eye Hospital, #404 Seolleung-ro, Gangnam-gu, Seoul, South Korea.
authors.forename: So Yeon
authors.initials: SY
authors.lastname: Lee
authors.affiliation: 06198 Nune Eye Hospital, #404 Seolleung-ro, Gangnam-gu, Seoul, South Korea. youngjhong@gmail.com.
authors.forename: Young Jae
authors.initials: YJ
authors.lastname: Hong
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D007429:Intraocular Pressure / Q000502:physiology; D016015:Logistic Models; D059012:Lost to Follow-Up; D057066:Low Tension Glaucoma / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology; D012160:Retina / Q000473:pathology; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
keywords: Baseline IOP; Glaucoma suspect; Incidence; Loss to follow-up; Normal-tension glaucoma; Retinal nerve fiber layer; Risk factors