Original Article Cataract Blindness in Osun State, Nigeria: Results of A
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[Downloaded free from http://www.meajo.org on Tuesday, January 13, 2015, IP: 41.234.9.9] || Click here to download free Android application for this journal Original Article Cataract Blindness in Osun State, Nigeria: Results of a Survey Olubayo U. Kolawole, Adeyinka O. Ashaye1, Abdulraheem O. Mahmoud2, Caroline O. Adeoti ABSTRACT Access this article online Website: Purpose: To estimate the burden of blindness and visual impairment due to cataract in www.meajo.org Egbedore Local Government Area of Osun State, Nigeria. DOI: Materials and Methods: Twenty clusters of 60 individuals who were 50 years or older were 10.4103/0974-9233.102741 selected by systematic random sampling from the entire community. A total of 1,183 persons Quick Response Code: were examined. Results: The age- and sex-adjusted prevalence of bilateral cataract-related blindness (visual acuity (VA) < 3/60) in people of 50 years and older was 2.0% (95% confidence interval (CI): 1.6–2.4%). The Cataract Surgical Coverage (CSC) (persons) was 12.1% and Couching Coverage (persons) was 11.8%. The age- and sex-adjusted prevalence of bilateral operable cataract (VA < 6/60) in people of 50 years and older was 2.7% (95% CI: 2.3–3.1%). In this last group, the cataract intervention (surgery + couching) coverage was 22.2%. The proportion of patients who could not attain 6/60 vision after surgery were 12.5, 87.5, and 92.9%, respectively, for patients who underwent intraocular lens (IOL) implantation, cataract surgery without IOL implantation and those who underwent couching. “Lack of awareness” (30.4%), “no need for surgery” (17.6%), cost (14.6%), fear (10.2%), “waiting for cataract to mature” (8.8%), AND “surgical services not available” (5.8%) were reasons why individuals with operable cataract did not undergo cataract surgery. Conclusions: Over 600 operable cataracts exist in this region of Nigeria. There is an urgent need for an effective, affordable, and accessible cataract outreach program. Sustained efforts have to be made to increase the number of IOL surgeries, by making IOL surgery available locally at an affordable cost, if not completely free. Key words: Barriers, Cataract Blindness, Nigeria, Prevalence, Surgery INTRODUCTION countries.7 In developed and even some developing countries, declining total fertility rate and increased life expectancy result ataract blindness presents an enormous problem in terms in sharp increase in the number of people aged 60 and above.8 Cof magnitude,1 functional disability, loss of self-esteem,2,3 In many of these countries, as the mean and median ages of the considerable economic loss, and social burden.4-6 It has been population increase, the prevalence of cataract and other age- estimated that cataract accounted for 47.8% of the 37 million related causes of blindness will increase, resulting in an increase people who were blind worldwide in 2002.1 Age-related demand for cataract surgery.9 cataract constitutes more than 80% of all cataracts, and a large proportion of the burden is borne by elderly people who live The results from the recent national blindness and visual in remote underserved rural communities of most developing impairment survey revealed that 1.8% of adult Nigerians Department of Ophthalmology, College of Health Sciences, Ladoke Akintola University of Technology, Osogbo, Osun State, 1Department of Ophthalmology, University College Hospital, Ibadan, 2Department of Ophthalmology, University of Ilorin Teaching Hospital, Ilorin, Nigeria Corresponding Author: Dr. Olubayo U. Kolawole, Department of Ophthalmology, College of Health Sciences, Ladoke Akintola University of Technology, Osogbo, Osun State, Nigeria. E-mail: [email protected] 364 Middle East African Journal of Ophthalmology, Volume 19, Number 4, October - December 2012 [Downloaded free from http://www.meajo.org on Tuesday, January 13, 2015, IP: 41.234.9.9] || Click here to download free Android application for this journal Kolawole, et al.: Cataract Blindness, Prevalence, Surgery, Barriers aged 40 and above had cataract-related blindness.10 However, caused by cataract. Thus, the prevalence of cataract blindness surveys conducted earlier showed that the prevalence of cataract in Egbedore LGA would be 0.56%. Assuming that cataract blindness among people aged 50 and above ranged between 2.1 blindness in individuals younger than 50 years is negligible, the and 3.8% in Northern Nigeria11-13 and 4.1% in the Niger Delta.14 prevalence of bilateral cataract blindness in people aged 50 and It was 0.84% in South-Western Nigeria.15 older is expected to be 0.56/9.31% = 6.01%. Egbedore is one of the 30 Local Government Areas (LGAs) in We allowed for a precision of ±30% of the likely prevalence Osun State, Nigeria. It is located in the South-Western part of bilateral cataract blindness, i.e., worst acceptable prevalence of Nigeria between Latitudes 07° 40″ and 07° 55″ N; and of 4.21% with a probability of 95%. For logistic reasons, we Longitudes 04° 20″ and 04° 35″ E. It covers an area of about selected a cluster size of 60 with design effect of 1.7 for cluster 102 km2. It shares borders with Irepodun (north), Ede North random sampling. Thus, the calculated sample size using the LGA (south), Ejigbo LGA (west), and Olorunda/Osogbo LGAs sample size menu of Epi-info 6.04 (Centers for Disease Control (east). Awo, the headquarters of the LGA, is about 5 km from and Prevention, Atlanta, GA, USA) was 1,017. Allowing for a Osogbo, the Osun State capital. While other settlements such 10% non-response rate, the minimum sample size was 1,130. as Okinni, Ido-Osun, Ofatedo, and Olorunsogo are near to Thus, 20 clusters of 60 eligible subjects each were randomly Osogbo and are peri-urban, the remaining settlements are selected from the community. essentially rural. The vegetation is that of the southern lowlands and tropical rain forest. The climate is mainly tropical with Clusters were selected from a census list of all settlements in the long wet season stretching from March to November.16 the entire Egbedore LGA and their respective populations. A Ophthalmic services for the LGA are provided mainly by five column with the cumulative population was added from which consultant ophthalmologists who work at Osogbo. Four of 20 clusters were selected through systematic random sampling. these ophthalmologists work at Ladoke Akintola University of Following this procedure, clusters were selected with a probability Technology Teaching Hospital (LTH), Osogbo; one works at the proportional to the size of the population. The sampling method General Hospital, Osogbo. All the ophthalmologists perform was designed to provide reliable estimates for the entire LGA. No cataract surgeries, even though only LTH is well equipped for stratification was made between rural and peri-urban settlements microsurgery. All the five ophthalmologists performed fewer because there was homogeneity of the study population with than 100 cataract surgeries in 2005. A surgical eye camp has respect to the risk of developing age-related cataract. never been held in the LGA. In each cluster, the starting point was selected randomly by The aim of this study was to estimate the contribution of spinning a bottle in the middle of the community and moving in cataract to the burden of blindness and visual impairment in the direction of the tip of the fallen bottle. All eligible subjects Egbedore LGA of Osun State in order to provide baseline data in all the households along that direction were enrolled until for developing and conducting viable cataract surgical services the required 60 persons had been registered. In each cluster, for the area. the local guide ensured that persons who were not members of selected households were not enrolled. Such persons were MATERIALS AND METHODS examined but were not included in the study. In clusters where fewer than 60 subjects were registered, eligible subjects were This was a population-based cross-sectional survey that was enrolled and examined from the nearest settlements to make conducted in the months of May, June, and October 2005. Persons up the required number. aged 50 years and above who had resided in the LGA for at least 6 months at the time of this study formed the target population. Ethical approval for the study was obtained from the Research and Ethical Committee of LTH. According to the 1991 population census data,17 the total population of Egbedore LGA was 40,293 and the annual growth The field work was carried out by a team which consisted of an rate was 3%. Although census data by sex and age group were not ophthalmologist, three assistants (secondary school leavers) who available for the LGA, from the national population estimates, were trained to register the subjects, measure and record VA, and 9.31% of the Nigerian population represented people aged 50 record the general information section on the survey form, and a and above.18 Thus, the 2005 projected population of the LGA local guide for each settlement who was a member of the community. was 59,823 people, of whom 5,570 were adults aged 50 and older. The results of a population-based survey19 conducted in Oral informed consent was obtained from each subject before data Egbedore LGA in 1998 indicated that 1.18% of the examined collection. A standard survey record form developed for Rapid population of all age groups were bilaterally blind with visual Assessment of Cataract Surgical Services (RACSS)20 by the WHO acuity (VA) of less than 3/60. Of all blindness, 47.4% was Prevention of Blindness and Deafness Programme was modified Middle East African Journal of Ophthalmology, Volume 19, Number 4, October - December 2012 365 [Downloaded free from http://www.meajo.org on Tuesday, January 13, 2015, IP: 41.234.9.9] || Click here to download free Android application for this journal Kolawole, et al.: Cataract Blindness, Prevalence, Surgery, Barriers and completed for each participant.