title: Demographic characteristics, patterns and risk factors for retinal vein occlusion in Nepal: a hospital-based case-control study.
abstract: OBJECTIVE
  Retinal vein occlusion (RVO) is an increasing problem leading to visual impairment in Nepal. Our study investigates the demographic characteristics, patterns and risk factors for RVO in this developing Asian country.
  
  
  METHODS
  This is a hospital-based case-control study conducted at the Tilganga Institute of Ophthalmology of Nepal during the period of January 2007 to January 2008. All consecutive new cases of RVO diagnosed at the Institute were included. Cases with intraocular inflammation or a prior history of intraocular injections, laser therapy or vitrectomy for RVO were excluded from the study. Age, sex and geographically matched subjects were recruited as a control group from patients who presented for regular eye examinations at the same hospital during the study period.
  
  
  RESULTS
  A total of 218 patients with RVO presented during the study period. The mean age of the patients was 61.1 + or - 12.3 years with more men (58.3%) than women. The mean age for control groups was 61.3 + or - 13.0 years. Seventy per cent of subjects had branch retinal vein occlusion, whereas central retinal vein occlusion was present in 26.6%. 63.9% of branch retinal vein occlusion was found in the superotemporal branch. Hypermetropia, primary open angle glaucoma, hypertension, mixed diabetes and hypertension, and heart disease were significantly higher in RVO cases as compared with the control group.
  
  
  CONCLUSIONS
  The demographic characteristics, patterns and risk factors of RVO in Nepal can help guide interventions against these blinding diseases in similar developing countries.
authors.affiliation: Tilganga Institute of Ophthalmology, Kathmandu, Nepal. rabathapa@live.com
authors.forename: Raba
authors.initials: R
authors.lastname: Thapa
authors.forename: Govinda
authors.initials: G
authors.lastname: Paudyal
authors.forename: Paul S
authors.initials: PS
authors.lastname: Bernstein
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003710:Demography; D003906:Developing Countries; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009390:Nepal / Q000453:epidemiology; D012170:Retinal Vein Occlusion / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology*; D012307:Risk Factors; D017678:Sex Distribution; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult