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Annals of African Medicine
Annals of African Medicine Society
ISSN: 1596-3519
Vol. 4, Num. 2, 2005, pp. 52-57
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Annals of African Medicine, Vol. 4, No. 2, June, 2005, pp. 52-57
RAPID
ASSESSMENT OF CATARACT BLINDNESS AMONG UGHELLI CLAN IN AN
URBAN/RURAL DISTRICT OF DELTA STATE, NIGERIA
1G. Patrick-Ferife, 2A. O. Ashaye and 2O.
O. Osuntokun
1Marierie
MemorialCentralHospital, UghelliDeltaState and 2Department
of Ophthalmology, College of Medicine, University of Ibadan, Ibadan, Nigeria
Reprint requests to: Dr.
A. O. Ashaye, Department of Ophthalmology, College of Medicine, University of
Ibadan, Ibadan, Nigeria
Code Number: am05014
Abstract
Background: A population based, rapid
assessment for cataract blindness was conducted in Ughelli North local
government area of DeltaState, an
urban/rural area of Nigeria between June and July 2001 with the aim
of establishing baseline data for developing cataract intervention services for
the area.
Method: A cluster random sampling
method was used based on the guidelines for the Rapid Assessment for Cataract
Surgery. A total of 8 clusters of 90 persons were randomly selected from the
8
communities that make up the Ughelli clan. Only people of 50 years and above
who had been resident in the area for up to six months were included. A total
of 684 persons were examined (91.2% coverage) using a designed survey form. The
barriers to the uptake of cataract surgery were also identified during the
survey. The WHO definitions of blindness and visual impairment according to
visual acuity were used as criteria for classification of visual blindness and
visual impairment.
Results: The prevalence
of bilateral cataract blindness (cataract causing visual acuity of less than 3/60 in
the better eye) for people of 50 years and above was 4.1% (95% CI: 2.96 to 5.24%)
with cataract accounting for 41.2% of all the blindness in this age
group. Prevalence of cataract blindness was higher in females than in males
(5.0% versus 3.6%) About 80% of the cataract blindness occurs in people of 70
years and above. The cataract surgical coverage for eyes was 4.5%; cataract
surgical coverage for couching was 18.2%. The major barriers to the uptake of
cataract surgical services were lack of awareness of eye care services in
nearby district (71.0%), the imagined high cost of the services (17.9%) the
perception of women that their health problems are not of immediate importance
(7.1%).
Conclusion:At the time of study
about 2000 person required immediate cataract surgery in the area. With an
estimated incidence of 400 new cases per year, there is a need to set up
cataract surgical services in the Ughelli North local government area. Special
attention should be given to reduction of cataract blindness in females.
Key words: Cataract, blindness, rapid assessment
Résumé
Introduction : Evaluation
rapide, basée sur une population de la cécité provoquée par une cataracte a été
effectuée dans ladministration locale du nord dUghelli de lÉtat de Delta,
une zone urbaine/rurale du Nigéria entre juin et juillet 2001 dans le but
détablir des données de base pour le développement du service dintervention
chirurgicale de la cataracte pour la région.
Méthode : Une méthode dun groupe déchantillonage au hasard a
été utilisée basée sur des directives pour lEvaluation Rapide pour
lintervention chirurgicale de la Cataracte. Un nombre total de 8 groupes
composés de 90 personnes ont été sélectionnés au hasard parmi les 8 communautés
dont le clan dUghelli est composé. Un nombre total de 684 personnes ont
été examinées soit 91,2% traitement à travers
lutilisation dun formulaire conçu pour faire un sondage.
Résultats : La
fréquence de la cécité de la cataracte bilatérale (la cataracte qui provoque
une acuité visuelle de moins de 3/60 dans le meilleur oeil) pour des peuples de
50 ans et plus était 4,1% soit 95% CL : 2,96 au 5,24%) dont la cataracte
constitue 41,2% de toute les cécités dans cette tranche dâge. La fréquence de
la cécité de la cataracte était élevée chez le sexe féminin plus que chez le
sexe masculin (5,0% contre 3,6%) Environ 80% de la cécité de la cataracte
arrivent chez des gens âgés de 70 ans et plus. Les traitements à travers
lintervention chirurgicale de la cataracte pour des yeux était 4,5%. Les
traitements pour lintervention chirurgicale pour le couching contitue 18,2%.
Les barrières principales contre les services dintervention chirurgicale de la
cataracte étaient manque de lopinion publique sur la conscience de services de
soins des yeux dans la région dà côté (71,0%), le soi-disant services à grands
frais, (17,9%), la conception des femmes que les problèmes rélatifs à leurs
santé nest pas durgence (7,1%).
Conclusion : Pendant
cette étude, environ 2000 personnes avaient besoin de lintervention
chirurgicale de la cataracte durgence dans cette région. Avec une fréquence
denviron 400 nouveaux cas chaque année, cest nécessaire de créer un service
dIntervention Chirurgicale de la Cataracte dans ladministration locale du
nord dUghelli. Une attention particulière devrait être portée sur la
reduction de la cécité de la cataracte chez des femmes.
Mots clés : cataracte, aveuglement, evaluation rapide
Introduction
Cataract
is the most common cause of blindness in most developing countries of which
Nigeria is one, accounting for more than 50% of blindness. The estimated
prevalence of cataract blindness varied widely in the different populations
ranging from 0.3 to 1.3%.1, 2 Studies on prevalence of cataract
blindness are few. 3-5 Most authors report the prevalence of
cataract blindness in blindness surveys. 6-8 Even then the reported
prevalence of blindness due to cataract vary.
Rapid assessment for cataract blindness is a
relatively easy and fast epidemiological method that enables eye health
personnel to collect data and develop a plan of action for cataract
intervention based on community needs. 9 It allows rational use of
scarce resources for data collation where funds for survey are not available.
This method was used in this study.
Neither planned national nor have district surveys
been conducted in Nigeria. Such exercises are major and the resources needed to
conduct such surveys are not available. Besides in Nigeria, large
variations in socio-economic conditions, age, gender and resource availability
is expected to cause variations in prevalence results between districts. The
study aims at the rapid assessment of cataract blindness in the population aged
50 years and above to make possible an estimation of the burden of cataract
blindness and implement cataract surgical services for the Ughelli North Local
Government area.
Patients and Methods
Delta State
Delta
state has a population of 3,372,080 (projections from 1991 national census)
with a growth rate of 3% per annum. With the adoption of the Primary HealthCare
(PHC) system for the national health policy, the overall responsibility of the
health care services of the state is maintained by the state ministry of
health. The management of the hospitals is directly under the state hospital
management board. Apart from government, private and missionary hospitals,
provides health care services in the state. There are 36 government state
hospitals, which fall under 10 medical zones. There are also several health
centers located in the local government area and managed by the local
government council.
Study location and population
The
Ughelli North local government area is one of the 25 local government areas of
the state. It has a total population of approximately 248,800 (Projected
figures 2000 the National Population Commission). It is estimated that people
of 50 years and above make up 20% of the population. It is made up of 7 clans
with Ughelli being the local government headquarters.
Ughelli clan, which is both urban and rural areas,
comprise of eight communities, which make up the two electoral wards. These
villages are Iwreko (presently referred to as UghelliTownship),
Ekiugbo, Otovwodo, Afisere, Ofoma, Ododegho, Eruemokouarien and Oteri clans.
The total population of these clans is approximately 99,404. These communities
are fairly homogenous in many ways.
The state government maintains a central hospital
located in UghelliTownship, which serves as a referral centre for the health
centers run by the local government councils. There are also several privately
owned health care facilities in the area. None of the latter hospital offered
eye care surgical services at the time of this study.
The States central hospital has a recently
established eye department, which offered optical services only; there were
also several private optical shops.
These health facilities were only able to offer limited eye care to its
population.
Sampling design
A cluster random sampling method as recommended
for rapid assessment of cataract blindness was done. For the purpose of
determining the sample size, we estimated the prevalence of cataract blindness
(< 3/60) to be 4.3% for adults 50 years and over. A
design effect of 1.0% was assumed for cluster sampling, a confidence interval
of 95% and a non-response rate of 10% were assumed. The target population was
20,000. This led a sample size of approximately 750 persons of 50 years and
above.
Four communities were randomly selected from the 8
communities. These are Ofoma, Afisere, Ugwru-Ughelli and UghelliTownship.
Based on the available population figures, the communities were divided into 8
clusters of 90 persons to attain the sample size of 750. In each cluster, all
persons of 50 years and above who consented to be included in the study were
examined.
In each cluster, the starting point was randomly
selected and beginning from there, the nearest door rule (i.e. the first house,
whose door is nearest to the door of the current house) was used for locating
the subjects.
The survey form was pretested amongst patients
presenting to the eye clinic of the central hospital, Ughelli and amendment
done before commencement of the survey.
Visits were made to the
National population commission office in the local government area to collect
information on the population and distribution in the area. The local
government council was also visited. Meetings were held with the leader of the
council, the supervising councilor on health and two other councilors of the
local government area, acquainting them with the planned survey and soliciting
for their support in mobilizing their various constituencies.
A tour of the study area was also undertaken; the
numbering of the houses has recently been concluded in some of the community.
The survey team
comprised of a team manager/researcher and five assistants (secondary school
leavers) who were fluent in the local language were recruited. They were
trained for three days on filling or survey forms, measuring and recording of
visual acuity.
Announcements about the
survey were made by the town criers in each community. The people were informed
of the target age group and that no payments were involved. The people were
reminded a day before the actual visit.
Field work
Consent
was sought from each subject. Those who refused been included were not coded.
The assistants filled the address and demographic data. For subjects who could
not remember their ages, the age was calculated from the estimated age at the
time of the eclipse in 1947, the visit of Queen Elizabeth in 1952, and also
from their position in the family. History and date of cataract surgery if
done, were also recorded.
Examination included a
visual acuity, a measurement using the Snellens chart or illiterate E chart
as appropriate at 6 metres. Individuals with visual acuity better than 6/18
were noted and allowed to go. Those with visual acuity less than 6/18
but better than 3/60 were referred to the central
hospital and those with visual acuity less than 3/60 were
further examined using the torch light and Ophthalmoscope. Dilated fundoscopy
was done when indicated. All identified bilateral/cataract blind individuals
were further interviewed on the reason for not seeking medical treatment. The
first volunteered answer was then recorded as a barrier for the uptake of
cataract surgical service. Results of the examination were recorded on the
survey forms. All subjects absent or unavailable at the time of the survey were
not revisited due to time constraints.
All minor ocular problems were treated in the field
and diagnosed cases and those with presbyopic symptoms were referred. At the
end of the day all forms were crosschecked by the researcher for errors and
corrected accordingly.
All data were included
on epinfo version 6.0 software and univariate analysis was done to assess the
prevalence of cataract blindness and cataract surgical coverage for eyes was
also calculated. Chi-square and odds ratio were calculated for the variables.
Results
A total of 684 persons aged > 50 years
were examined and 15 others did not consent to be included in the study. Thus
the overall coverage was 91.2%.
Of all persons examined,
persons who were 50-59 years made up 42.1% of the sample (Table 1). There were
more men than women in all age groups. Of the 15 others who did not give
consent to be studied, 10 were males and 5 were females. Their ages could not
be ascertained.
Farming was the most common occupation in the people
of this age group, being the occupation in 55% (376) of study subjects. The
other occupations of the subjects were trading, 19% (128). Others include
teaching, civil service and retirees (11%) and a group of artisan (15%) which includes
mechanics, drivers.
The prevalence of blindness (visual acuity less than 3/60
in the better eye) in persons 50 years and above was 9.9%.
Twenty eight out of the
68 blind subjects were blind from cataract, thus cataract accounted for 41.2%
of all blindness in people of 50 years and above. The prevalence of cataract
blindness in the persons 50 years and older studied was 4.1% (95% CI 2.96% to
5.24%) (Table 2). Other causes of blindness identified include uncorrected
aphakia (23.5%), glaucoma and posterior segment disorders. The prevalence of
cataract blindness was higher in females (5.0%) than in males (3.6%).
Ninety two persons (13.4%) were found to be unilaterally
blind (with visual acuity in the worse eye of less than 3/60). Out of these,
32
were due to cataract, thus accounting for 34.7% of all unilateral blindness.
Another major cause of unilateral blindness in this age group was
disorganized/phthysical globe.
Twenty eyes of 20 subjects had undergone cataract
surgery. 16 eyes (80%) of those were done by couching, 4 eyes had intracapsular
cataract extraction, only one of those subjects had spectacle correction but in
that subject, corrected visual acuity was less than 3/60. The Cataract Surgical
Coverage (CSC) eyes for visual acuity less than 3/60 was
therefore 4.5%, and the CSC for couching was 18.2%.
Out of the 28 cataract blinds, 20(71%) were not aware
of the availability of cataract surgical services in nearby districts. 5
subjects knew cataract to be the cause of blindness but expected the cost of
hospital services to be out of their reach. 2 others who were females realized
they needed to seek help but could not because of their family situation since
there was no one to look after their families in their absence. Thus the major
barriers to uptake of available services was lack of knowledge about the
services (71%) cost (17.9%) and domestic responsibilities (7.1%) and poor
outcome (4%).
Table
1: Age and sex of the study population
Age (years)
|
F (%)
|
M (%)
|
Total (%)
|
50 59
|
132 (45.2)
|
156(54.4)
|
288(42.1)
|
60 69
|
60 (38.5)
|
96 (61.5)
|
156 (22.8)
|
≥70
|
48 (20.0)
|
192 (80.0)
|
240 (35.1)
|
Total
|
240 (35.1)
|
444 (64.9)
|
684 (100)
|
Table 2: Age and sex of
patients with cataract blindness
Age (years)
|
F
|
|
M
|
|
Total
|
|
|
n
|
No. blind
|
n
|
No. blind
|
n
|
No. blind
|
50 59
|
132
|
0 (0)
|
156
|
0 (0)
|
288
|
0 (0)
|
60 69
|
60
|
4 (6.7)
|
96
|
0 (0)
|
156
|
4 (2.6)
|
≥70
|
48
|
8 (16.7)
|
192
|
16 (8.3)
|
240
|
24 (1.0)
|
Total
|
240
|
12 (5.0)
|
444
|
16 (3.6)
|
684
|
28 (4.1)
|
Discussions
This
was the first eye survey to be conducted among the Ughelli clan of Delta State, Nigeria. The
inhabitants were very co-operative and hospitable. One of the communities
visited requested that a similar test be conducted for the youths. The overall
coverage of 91% attests to this. Although the coverage was high, the expected
90 persons per cluster was not achieved as some subjects were absent and
revisits were not done because of cost constraints.
The Rapid Assessment of Cataract Surgical Services
(RACSS) survey has been scientifically designed and tested in several states
and districts in India for its methodology and validity. 4 The
RACSS was designed for easy assessment of cataract blindness by health workers,
who on identifying such cases refer them to the examination centre for
confirmation of diagnosis.
In this study all
eligible subjects had a complete visual acuity testing using the Snellens
chart as opposed to the RACSS vision testing which starts the visual acuity
testing at 6/18. This modification was included, as these people have never had
their eyes tested before. This created a lot of awareness and demand and need
for eye care service as most of the referred subjects later presented at the
eye clinic of the central hospital.
The RACSS was applied to Ughelli clan of DeltaState, a
homogenous group of people, as an initial step to conducting the same study
among the less homogenous groups of people in Ughelli local government areas.
The findings here only apply to the group examined.
The prevalence of bilateral blindness (9.9%) in those
50 years and above among the Ughelli clan was much higher than the estimate for
the region. 1,2,10 The prevalence of cataract blindness in those 50
years and above among the Ughelli clan in Ughelli North local government area
was 4.1% accounting for 41.2% of all blindness. Cataract blindness was two
times higher than estimated for Ughelli area and is much higher than the 2.4%
reported by Ezepue in adjacent EnuguState but compares with the reported prevalence of 4.93% in
the KarmatakaState of India. 11
Enugu is more urban than Ughelli and has more eye-care
facilities, although it is a neighbouring state, its eye care services were
remote to the people of Ughelli, and this may account for the differences
observed between the two neighbouring districts and states. Variations of
results within states may also reflect large variations in demographical and
socioeconomic conditions even among neighbouring states or districts. This
justifies the
use of RACSS as a rapid
assessment tool with moderate cost to provide information needed to plan at
district level. State or National figures may not be valid for individual
districts.
Unlike other settings in
developing countries men outnumbered women, this unusual age-sex reversal could
not be adequately explained but this reversal was found in Ethiopia. 11 Despite
this reversal of ratio between men and women, the rate of cataract blindness in
women were more presumably because of the lower chances of intervention. These
women specifically need eye care services directed to them.
As in most developing countries, persons who are 70 years and above are
increasing as people are living longer; the high rate of cataract blindness in subjects
70 years of age found in this study suggests that efforts are needed to promote
blindness prevention and treatment as a programme for the most elderly.
Of the subjects who were aphakic identified in this
study, only 4 subjects had intracapsular cataract extraction. The other 3
persons had no aphakic correction. The subject who had aphakic correction had a
corrected visual acuity less than 3/60 depicting a poor visual outcome. The
subject had optic atrophy from onchocerciasis.
Couching was the main form of cataract intervention
available in the area. These couchers reside amongst the people and therefore
their services are readily available. Correction of the ensuing refractive
error is not priority for these couchers hence the high prevalence of
uncorrected aphakia. The prevalence of uncorrected aphakia is also high in
patients who had intracapsular cataract extraction (ICCE). The difficulties in
adjusting to aphakic glasses, the loss of the spectacles prevent them from
using such spectacles. The occupation of most of these people farming is also a
hindrance to the wearing of aphakic spectacles.
It is possible that the subject with poor visual
outcome became an aphakic demotivator. Proper screening of patients for
cataract surgery could eliminate problems of aphakic demotivators.
The Cataract Surgical Coverage (CSC) though an
indicator to measure the impact of cataract intervention programmes, also shows
clearly the extent to which the problem of cataract blindness has been reduced.
This study found a Cataract Surgical Coverage (CSC) (eyes) in this urban/rural
community to be only 4.5% while CSC (eyes) for couching was 18.2%. This figure
is lower than 16% reported for a rural community in Northern Nigeria.
12 Low CSC is expected in a grossly underserved area. The poor level
of awareness of eye care in the neighbouring community, the presence of aphakic
demotivator found in areas such as this community and even where there are eye
services are frequent findings in developing countries. 3-8 In
contrast, the CSC calculated from a population based surveys of 19 rural
districts found a range of 42% - 68% for persons and 22%-45% for eyes. 9
Over 70% of the cataract blinds in this survey were
not aware of available services located in neighbouring States. High cost of
surgery was the expectation of subjects. This could have resulted from the high
cost the subjects pay for other health services. Commitments of women to their
families were other barriers to uptake of surgery identified in this study.
Presence of aphakic demotivators may explain the high prevalence of cataract
blindness in the persons studied. These are similar to barriers found in some
African developing countries where there is maldistribution of services and
lack of expertise, and lack of organized eye care. 11
In this study, 28
bilateral and 32 unilateral cataract blinds were identified. A total of 60
(8.8%) persons needed cataract surgery. With approximately 20,000 persons
expected to be 50 years and above, it is estimated that 1,760 persons require
immediate surgery. The cataract surgical service, to be planned has to deliver
cataract surgery through a primary health/eye care approach, thus making the service
acceptable, accessible, affordable and using scientifically sound methods. It
would also involve the community at all levels and other intersectoral inputs
essential for the successful outcome of such a programme.
When no information is available on the distribution
of the different causes of blindness in the general population, it is difficult
to have an effective, preventive and curative eye care programme.
This survey has assessed the magnitude of cataract
blindness in people who were 50 years and above among the Ughelli clan an
urban/rural community in the Ughelli North local government area of Delta
State, concludes that the prevalence of cataract blindness was much higher than
a neghbouring district, was more in older age groups and in females. There may
be a large variation of blindness rates in different parts of Nigeria.
National survey will have to take this unto consideration. The major barriers
against the utilization of eye care facilities is a challenge and needs to be
tackled so as to reduce the burden of blindness in this underserved community.
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