title: Prevalence and pattern of vitreo-retinal diseases in Nepal: the Bhaktapur glaucoma study.
abstract: BACKGROUND
  Vitreo-retinal diseases are among the leading causes of visual impairment and blindness worldwide. This study reports the prevalence and pattern of vitreo-retinal diseases in the Bhaktapur Glaucoma Study (BGS), a population based study conducted in Nepal.
  
  
  METHODS
  BGS was a population based cross-sectional study involving 4800 subjects aged 40 years and over from Bhaktapur district. Subjects were selected using a cluster sampling methodology and a door-to-door enumeration. All subjects underwent a detailed ocular examination at the base hospital which included log MAR visual acuity, refraction, applanation tonometry and a dilated fundus examination. Fundus photography, optical coherence tomography and fundus fluorescein angiography were performed where indicated.
  
  
  RESULTS
  Complete data was available for 3966 (82.62%) out of the total of 4800 enumerated subjects. The mean age was 55.08 years (SD 11.51). The overall prevalence of vitreo-retinal disorders was 5.35% (95% CI, 4.67 - 6.09). Increasing age was associated with a higher prevalence of vitreo-retinal disorders (P < 0.001). The prevalence of diabetes mellitus was 7.69% (95% CI, 6.88 - 8.56). Age-related macular degeneration (AMD) was the most common vitreo-retinal disorder with a prevalence of 1.50% (95% CI, 1.15 - 1.94), increasing significantly with age. The prevalence of diabetic retinopathy among the study population was 0.78% (95% CI, 0.53 - 1.11) and among the diabetic population 10.16% (95% CI, 7.01 - 14.12). The population prevalence of other retinal disorders were hypertensive retinopathy 0.88%, macular scar 0.37%, retinal vein occlusion 0.50%, macular hole 0.20%, retinitis pigmentosa 0.12%. and retinal detachment 0.10%.The prevalence of low vision and blindness due to vitreo-retinal disorders was 1.53% (95% CI, 1.18 - 1.97) and 0.65% (95% CI, 0.43 - 0.96), respectively. The prevalence of low vision and blindness was 28.77% (95% CI, 22.78-35.37) and 12.26% (95% CI, 8.17-17.45), respectively among cases with vitreo-retinal disorders. Blindness was observed to be unilateral in 19 cases (73%), and bilateral in 7 cases (27%).
  
  
  CONCLUSIONS
  The prevalence of vitreo-retinal disorders in this Nepalese population was 5.35%, which increased significantly with age. AMD was the predominant retinal condition followed by diabetic retinopathy. One fourth of the subjects with vitreo-retinal disorder had low vision. Taking into consideration the aging population and emerging systemic diseases such as diabetes mellitus and hypertension, vitreo-retinal disorders could be of future public health importance.
authors.affiliation: Nepal Glaucoma Eye Clinic, Tilganga Institute of Ophthalmology, Kathmandu, Nepal. suman.thapa@tilganga.org
authors.forename: Suman S
authors.initials: SS
authors.lastname: Thapa
authors.forename: Raba
authors.initials: R
authors.lastname: Thapa
authors.forename: Indira
authors.initials: I
authors.lastname: Paudyal
authors.forename: Shankar
authors.initials: S
authors.lastname: Khanal
authors.forename: Jaskirat
authors.initials: J
authors.lastname: Aujla
authors.forename: Govinda
authors.initials: G
authors.lastname: Paudyal
authors.forename: Ger van
authors.initials: Gv
authors.lastname: Rens
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001766:Blindness / Q000453:epidemiology / Q000209:etiology; D003430:Cross-Sectional Studies; D005128:Eye Diseases / Q000150:complications / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009390:Nepal / Q000453:epidemiology; D015995:Prevalence; D012164:Retinal Diseases / Q000453:epidemiology; D017678:Sex Distribution; D015354:Vision, Low / Q000453:epidemiology / Q000209:etiology; D014822:Vitreous Body; D014823:Vitreous Hemorrhage
references.citation: Bull World Health Organ. 2001;79(3):227-32
references.pmid: 11285667
references.citation: Am J Ophthalmol. 2006 Mar;141(3):589-91
references.pmid: 16490523
references.citation: Ophthalmology. 1995 Oct;102(10):1450-60
references.pmid: 9097791
references.citation: Indian Heart J. 2006 Jan-Feb;58(1):34-7
references.pmid: 18984928
references.citation: Trans Am Ophthalmol Soc. 2000;98:133-41; discussion 141-3
references.pmid: 11190017
references.citation: Invest Ophthalmol Vis Sci. 2007 Mar;48(3):1007-11
references.pmid: 17325139
references.citation: Ophthalmic Epidemiol. 2008 Jul-Aug;15(4):279-81
references.pmid: 18780262
references.citation: Bull World Health Organ. 2004 Nov;82(11):844-51
references.pmid: 15640920
references.citation: Arch Ophthalmol. 2004 Apr;122(4):552-63
references.pmid: 15078674
references.citation: Ophthalmology. 1992 Jun;99(6):933-43
references.pmid: 1630784
references.citation: Ophthalmology. 2009 Feb;116(2):311-8
references.pmid: 19084275
references.citation: Bull World Health Organ. 2001;79(3):244-8
references.pmid: 11285670
references.citation: Diabetes Care. 2004 May;27(5):1047-53
references.pmid: 15111519
references.citation: Acta Ophthalmol Scand. 2001 Oct;79(5):441-9
references.pmid: 11594976
references.citation: Clin Exp Ophthalmol. 2011 Dec;39(9):851-7
references.pmid: 21631676
references.citation: Ophthalmology. 2004 Jul;111(7):1288-97
references.pmid: 15234128
references.citation: Retina. 2008 May;28(5):755-62
references.pmid: 18463522
references.citation: World Health Stat Q. 1991;44(3):98-106
references.pmid: 1949887
references.citation: Arch Ophthalmol. 1998 May;116(5):653-8
references.pmid: 9596502
references.citation: Ophthalmic Epidemiol. 2010 Mar;17(2):82-9
references.pmid: 20302430
references.citation: Arch Ophthalmol. 1989 Jul;107(7):991-7
references.pmid: 2751471
references.citation: Nepal Med Coll J. 2008 Sep;10(3):160-3
references.pmid: 19253859
references.citation: Arch Ophthalmol. 1995 Jun;113(6):728-35
references.pmid: 7786213
references.citation: J Pak Med Assoc. 2011 Jun;61(6):544-9
references.pmid: 22204207
references.citation: Br J Ophthalmol. 2008 Oct;92(10):1316-9
references.pmid: 18684751
references.citation: Ophthalmology. 2009 Mar;116(3):461-7
references.pmid: 19168222
references.citation: Kathmandu Univ Med J (KUMJ). 2011 Jan-Mar;9(33):13-8
references.pmid: 22610802
references.citation: Arch Ophthalmol. 2004 Apr;122(4):564-72
references.pmid: 15078675
references.citation: Mol Vis. 1999 Nov 03;5:26
references.pmid: 10562650
references.citation: BMC Ophthalmol. 2011 Jan 21;11:2
references.pmid: 21255382
references.citation: Clin Exp Ophthalmol. 2008 Apr;36(3):257-60
references.pmid: 18412595
references.citation: Ophthalmology. 2007 Jun;114(6):1157-63
references.pmid: 17337063
references.citation: Jpn J Ophthalmol. 1987;31(3):349-67
references.pmid: 3430853
references.citation: Ophthalmology. 1991 May;98(5 Suppl):766-85
references.pmid: 2062512
references.citation: Ophthalmology. 2006 Aug;113(8):1354-62
references.pmid: 16877074
references.citation: Kathmandu Univ Med J (KUMJ). 2011 Jul-Sep;9(35):165-9
references.pmid: 22609500
references.citation: Clin Exp Ophthalmol. 2011 Mar;39(2):126-34
references.pmid: 21040314
references.citation: Lancet. 1998 May 2;351(9112):1312-6
references.pmid: 9643793
references.citation: Invest Ophthalmol Vis Sci. 2005 Dec;46(12):4442-9
references.pmid: 16303932
references.citation: Indian J Ophthalmol. 1998 Jun;46(2):65-6
references.pmid: 9847477
references.citation: Arch Ophthalmol. 2004 Apr;122(4):581-6
references.pmid: 15078677
references.citation: Arch Ophthalmol. 1996 Oct;114(10):1243-7
references.pmid: 8859084
references.citation: Ophthalmology. 2008 Nov;115(11):1965-72
references.pmid: 18684506
references.citation: Surv Ophthalmol. 1995 Mar-Apr;39(5):367-74
references.pmid: 7604360
references.citation: Ophthalmology. 2008 Nov;115(11):1869-75
references.pmid: 18584872
references.citation: Br J Ophthalmol. 2006 Apr;90(4):411-6
references.pmid: 16547315
references.citation: Invest Ophthalmol Vis Sci. 2010 Jun;51(6):3205-9
references.pmid: 20071683