Cargando…

Six-Year Incidence of Blindness and Visual Impairment in Kenya: The Nakuru Eye Disease Cohort Study

PURPOSE: To describe the cumulative 6-year incidence of visual impairment (VI) and blindness in an adult Kenyan population. The Nakuru Posterior Segment Eye Disease Study is a population-based sample of 4414 participants aged ≥50 years, enrolled in 2007–2008. Of these, 2170 (50%) were reexamined in...

Descripción completa

Detalles Bibliográficos
Autores principales: Bastawrous, Andrew, Mathenge, Wanjiku, Wing, Kevin, Rono, Hillary, Gichangi, Michael, Weiss, Helen A., Macleod, David, Foster, Allen, Burton, Matthew J., Kuper, Hannah
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Association for Research in Vision and Ophthalmology 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5102568/
https://www.ncbi.nlm.nih.gov/pubmed/27820953
http://dx.doi.org/10.1167/iovs.16-19835
_version_ 1782466445434683392
author Bastawrous, Andrew
Mathenge, Wanjiku
Wing, Kevin
Rono, Hillary
Gichangi, Michael
Weiss, Helen A.
Macleod, David
Foster, Allen
Burton, Matthew J.
Kuper, Hannah
author_facet Bastawrous, Andrew
Mathenge, Wanjiku
Wing, Kevin
Rono, Hillary
Gichangi, Michael
Weiss, Helen A.
Macleod, David
Foster, Allen
Burton, Matthew J.
Kuper, Hannah
author_sort Bastawrous, Andrew
collection PubMed
description PURPOSE: To describe the cumulative 6-year incidence of visual impairment (VI) and blindness in an adult Kenyan population. The Nakuru Posterior Segment Eye Disease Study is a population-based sample of 4414 participants aged ≥50 years, enrolled in 2007–2008. Of these, 2170 (50%) were reexamined in 2013–2014. METHODS: The World Health Organization (WHO) and US definitions were used to calculate presenting visual acuity classifications based on logMAR visual acuity tests at baseline and follow-up. Detailed ophthalmic and anthropometric examinations as well as a questionnaire, which included past medical and ophthalmic history, were used to assess risk factors for study participation and vision loss. Cumulative incidence of VI and blindness, and factors associated with these outcomes, were estimated. Inverse probability weighting was used to adjust for nonparticipation. RESULTS: Visual acuity measurements were available for 2164 (99.7%) participants. Using WHO definitions, the 6-year cumulative incidence of VI was 11.9% (95%CI [confidence interval]: 10.3–13.8%) and blindness was 1.51% (95%CI: 1.0–2.2%); using the US classification, the cumulative incidence of blindness was 2.70% (95%CI: 1.8–3.2%). Incidence of VI increased strongly with older age, and independently with being diabetic. There are an estimated 21 new cases of VI per year in people aged ≥50 years per 1000 people, of whom 3 are blind. Therefore in Kenya we estimate that there are 92,000 new cases of VI in people aged ≥50 years per year, of whom 11,600 are blind, out of a total population of approximately 4.3 million people aged 50 and above. CONCLUSIONS: The incidence of VI and blindness in this older Kenyan population was considerably higher than in comparable studies worldwide. A continued effort to strengthen the eye health system is necessary to support the growing unmet need in an aging and growing population.
format Online
Article
Text
id pubmed-5102568
institution National Center for Biotechnology Information
language English
publishDate 2016
publisher The Association for Research in Vision and Ophthalmology
record_format MEDLINE/PubMed
spelling pubmed-51025682016-11-10 Six-Year Incidence of Blindness and Visual Impairment in Kenya: The Nakuru Eye Disease Cohort Study Bastawrous, Andrew Mathenge, Wanjiku Wing, Kevin Rono, Hillary Gichangi, Michael Weiss, Helen A. Macleod, David Foster, Allen Burton, Matthew J. Kuper, Hannah Invest Ophthalmol Vis Sci Clinical and Epidemiologic Research PURPOSE: To describe the cumulative 6-year incidence of visual impairment (VI) and blindness in an adult Kenyan population. The Nakuru Posterior Segment Eye Disease Study is a population-based sample of 4414 participants aged ≥50 years, enrolled in 2007–2008. Of these, 2170 (50%) were reexamined in 2013–2014. METHODS: The World Health Organization (WHO) and US definitions were used to calculate presenting visual acuity classifications based on logMAR visual acuity tests at baseline and follow-up. Detailed ophthalmic and anthropometric examinations as well as a questionnaire, which included past medical and ophthalmic history, were used to assess risk factors for study participation and vision loss. Cumulative incidence of VI and blindness, and factors associated with these outcomes, were estimated. Inverse probability weighting was used to adjust for nonparticipation. RESULTS: Visual acuity measurements were available for 2164 (99.7%) participants. Using WHO definitions, the 6-year cumulative incidence of VI was 11.9% (95%CI [confidence interval]: 10.3–13.8%) and blindness was 1.51% (95%CI: 1.0–2.2%); using the US classification, the cumulative incidence of blindness was 2.70% (95%CI: 1.8–3.2%). Incidence of VI increased strongly with older age, and independently with being diabetic. There are an estimated 21 new cases of VI per year in people aged ≥50 years per 1000 people, of whom 3 are blind. Therefore in Kenya we estimate that there are 92,000 new cases of VI in people aged ≥50 years per year, of whom 11,600 are blind, out of a total population of approximately 4.3 million people aged 50 and above. CONCLUSIONS: The incidence of VI and blindness in this older Kenyan population was considerably higher than in comparable studies worldwide. A continued effort to strengthen the eye health system is necessary to support the growing unmet need in an aging and growing population. The Association for Research in Vision and Ophthalmology 2016-11 /pmc/articles/PMC5102568/ /pubmed/27820953 http://dx.doi.org/10.1167/iovs.16-19835 Text en http://creativecommons.org/licenses/by/4.0/ This work is licensed under a Creative Commons Attribution 4.0 International License.
spellingShingle Clinical and Epidemiologic Research
Bastawrous, Andrew
Mathenge, Wanjiku
Wing, Kevin
Rono, Hillary
Gichangi, Michael
Weiss, Helen A.
Macleod, David
Foster, Allen
Burton, Matthew J.
Kuper, Hannah
Six-Year Incidence of Blindness and Visual Impairment in Kenya: The Nakuru Eye Disease Cohort Study
title Six-Year Incidence of Blindness and Visual Impairment in Kenya: The Nakuru Eye Disease Cohort Study
title_full Six-Year Incidence of Blindness and Visual Impairment in Kenya: The Nakuru Eye Disease Cohort Study
title_fullStr Six-Year Incidence of Blindness and Visual Impairment in Kenya: The Nakuru Eye Disease Cohort Study
title_full_unstemmed Six-Year Incidence of Blindness and Visual Impairment in Kenya: The Nakuru Eye Disease Cohort Study
title_short Six-Year Incidence of Blindness and Visual Impairment in Kenya: The Nakuru Eye Disease Cohort Study
title_sort six-year incidence of blindness and visual impairment in kenya: the nakuru eye disease cohort study
topic Clinical and Epidemiologic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5102568/
https://www.ncbi.nlm.nih.gov/pubmed/27820953
http://dx.doi.org/10.1167/iovs.16-19835
work_keys_str_mv AT bastawrousandrew sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy
AT mathengewanjiku sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy
AT wingkevin sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy
AT ronohillary sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy
AT gichangimichael sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy
AT weisshelena sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy
AT macleoddavid sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy
AT fosterallen sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy
AT burtonmatthewj sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy
AT kuperhannah sixyearincidenceofblindnessandvisualimpairmentinkenyathenakurueyediseasecohortstudy