ABSTRACT
UmP/h@8 Purpose: To quantify the prevalence of cataract, the outcomes
G5BfN
U of cataract surgery and the factors related to
,q`\\d unoperated cataract in Australia.
hn
GZ= Methods: Participants were recruited from the Visual
2`K=Hby Impairment Project: a cluster, stratified sample of more than
]m3HF& 5000 Victorians aged 40 years and over. At examination
*w`sM%]Rq sites interviews, clinical examinations and lens photography
z\W64^'"Z were performed. Cataract was defined in participants who
Wa
Rw05r had: had previous cataract surgery, cortical cataract greater
i>`%TW:g than 4/16, nuclear greater than Wilmer standard 2, or
/hR&8 `\\ posterior subcapsular greater than 1 mm2.
+5*95-;0 Results: The participant group comprised 3271 Melbourne
E<Y$>uKA residents, 403 Melbourne nursing home residents and 1473
(mpNcOY<D rural residents.The weighted rate of any cataract in Victoria
"%w u2%i was 21.5%. The overall weighted rate of prior cataract
P/eeC" surgery was 3.79%. Two hundred and forty-nine eyes had
IFL*kB had prior cataract surgery. Of these 249 procedures, 49
)mT<MkP (20%) were aphakic, 6 (2.4%) had anterior chamber
b2Fe<~S{ intraocular lenses and 194 (78%) had posterior chamber
(y~TL*B intraocular lenses.Two hundred and eleven of these operated
1.GQau~ eyes (85%) had best-corrected visual acuity of 6/12 or
`*R:gE= better, the legal requirement for a driver’s license.Twentyseven
rq].UCj (11%) had visual acuity of less than 6/18 (moderate
I+!0 O vision impairment). Complications of cataract surgery
![=yi
tB caused reduced vision in four of the 27 eyes (15%), or 1.9%
+I|vzz`ZVr of operated eyes. Three of these four eyes had undergone
hL{KRRf> intracapsular cataract extraction and the fourth eye had an
[RhO$c$[\ opaque posterior capsule. No one had bilateral vision
VlsnL8DV impairment as a result of cataract surgery. Surprisingly, no
+a+Om73B2 particular demographic factors (such as age, gender, rural
1>h]{%I residence, occupation, employment status, health insurance
zRr*7G status, ethnicity) were related to the presence of unoperated
]{@-HTt cataract.
p_%Rt"! Conclusions: Although the overall prevalence of cataract is
2fd{hJDq;5 quite high, no particular subgroup is systematically underserviced
$'M!HJxb in terms of cataract surgery. Overall, the results of
T(Eugl" cataract surgery are very good, with the majority of eyes
"+G8d'%YV achieving driving vision following cataract extraction.
W^l-Y%a/o Key words: cataract extraction, health planning, health
!%c\N8<>GD services accessibility, prevalence
oUU1+F- INTRODUCTION
H* *Xu;/5@ Cataract is the leading cause of blindness worldwide and, in
aqk!T%fg Australia, cataract extractions account for the majority of all
kt:!
7 ophthalmic procedures.1 Over the period 1985–94, the rate
@\#td5' of cataract surgery in Australia was twice as high as would be
}o`76rDN expected from the growth in the elderly population.1
&Z%?!.4j@ Although there have been a number of studies reporting
L4nYXW0y the prevalence of cataract in various populations,2–6 there is
ZD{LXJ{Vm little information about determinants of cataract surgery in
0 kW,I the population. A previous survey of Australian ophthalmologists
C~/a- showed that patient concern and lifestyle, rather
.?$gpM?i than visual acuity itself, are the primary factors for referral
%EB/b for cataract surgery.7 This supports prior research which has
4Fr
shown that visual acuity is not a strong predictor of need for
ep{FpB cataract surgery.8,9 Elsewhere, socioeconomic status has
eJ-nKkg~a been shown to be related to cataract surgery rates.10
4o[{>gW
To appropriately plan health care services, information is
\dah^mw" needed about the prevalence of age-related cataract in the
IH+|}z4N?> community as well as the factors associated with cataract
Z,PPu&lmE/ surgery. The purpose of this study is to quantify the prevalence
tKXI
k9e of any cataract in Australia, to describe the factors
7@W>E;go related to unoperated cataract in the community and to
9hyn`u. describe the visual outcomes of cataract surgery.
qJ-/7-$ ^ METHODS
b&
U62iq Study population
y?3;06y| Details about the study methodology for the Visual
'LDQgC*% Impairment Project have been published previously.11
wUJcmM; Briefly, cluster sampling within three strata was employed to
"" EQE>d recruit subjects aged 40 years and over to participate.
zfdl
45 Within the Melbourne Statistical Division, nine pairs of
]6j{@z?{ census collector districts were randomly selected. Fourteen
.T`%tJ-Em nursing homes within a 5 km radius of these nine test sites
<F'\lA9 were randomly chosen to recruit nursing home residents.
cU Clinical and Experimental Ophthalmology (2000) 28, 77–82
CTmT@A{ Original Article
{M)Nnst"~ Operated and unoperated cataract in Australia
h{qgEIk& Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
#<xm. Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
g
RzxLf`K n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
[V`r^ Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au C,eu9wOT 78 McCarty et al.
.6J$,.Ig Finally, four pairs of census collector districts in four rural
F"mmLao Victorian communities were randomly selected to recruit rural
|uJ%5y# residents. A household census was conducted to identify
~$J2g
eligible residents aged 40 years and over who had been a
Iga0
24KR resident at that address for at least 6 months. At the time of
~VB1OLgv#. the household census, basic information about age, sex,
G!yPw:X country of birth, language spoken at home, education, use of
Ho]su? corrective spectacles and use of eye care services was collected.
19] E 5'AI Eligible residents were then invited to attend a local
xyxy`qR A examination site for a more detailed interview and examination.
n&!-9:0 The study protocol was approved by the Royal Victorian
9tnD=A<PS Eye and Ear Hospital Human Research Ethics Committee.
u1.BN>G Assessment of cataract
eJX#@`K A standardized ophthalmic examination was performed after
VtohL+ pupil dilatation with one drop of 10% phenylephrine
uw8f ~:LT hydrochloride. Lens opacities were graded clinically at the
ajpXL time of the examination and subsequently from photos using
(-co. the Wilmer cataract photo-grading system.12 Cortical and
e#q}F>/L posterior subcapsular (PSC) opacities were assessed on
D/' dTrR retroillumination and measured as the proportion (in 1/16)
ss-D(K" of pupil circumference occupied by opacity. For this analysis,
yh=N@Z*zP cortical cataract was defined as 4/16 or greater opacity,
q cno^8R PSC cataract was defined as opacity equal to or greater than
P93@;{c( 1 mm2 and nuclear cataract was defined as opacity equal to
{ xB3S_,8 or greater than Wilmer standard 2,12 independent of visual
Ir]\|t acuity. Examples of the minimum opacities defined as cortical,
?h2}#wg nuclear and PSC cataract are presented in Figure 1.
Y9|!+,
Bilateral congenital cataracts or cataracts secondary to
M^I(OuRMeI intraocular inflammation or trauma were excluded from the
;wD)hNLAvR analysis. Two cases of bilateral secondary cataract and eight
x)VJFuqy cases of bilateral congenital cataract were excluded from the
i mM_H;-X analyses.
tnIX:6 A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
.e5Mnd%$M Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
.
]M"#
\
height set to an incident angle of 30° was used for examinations.
WPDyu
.QD Ektachrome® 200 ASA colour slide film (Eastman
=w^M{W.w Kodak Company, Rochester, NY, USA) was used to photograph
I2DpRMy the nuclear opacities. The cortical opacities were
YbLW/E\T photographed with an Oxford® retroillumination camera
y?!"6t7& (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
J^/p
( film (Eastman Kodak). Photographs were graded separately
Rva$IX^] by two research assistants and discrepancies were adjudicated
eiOW#_"\ by an independent reviewer. Any discrepancies
"ITIhnE between the clinical grades and the photograph grades were
6zn5UW#q resolved. Except in cases where photographs were missing,
Qci]i)s$js the photograph grades were used in the analyses. Photograph
MY/}-*| grades were available for 4301 (84%) for cortical
iR0y"Cii cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
1&$ nVQ for PSC cataract. Cataract status was classified according to
c"xK`%e the severity of the opacity in the worse eye.
E!AE4B1bd Assessment of risk factors
u2[w# A standardized questionnaire was used to obtain information
d5l UGRg about education, employment and ethnic background.11
W'.m'3#z Specific information was elicited on the occurrence, duration
wdZ/Xp9
] and treatment of a number of medical conditions,
Lh<).<S including ocular trauma, arthritis, diabetes, gout, hypertension
b u"!jHPB and mental illness. Information about the use, dose and
~v"L!=~G;a duration of tobacco, alcohol, analgesics and steriods were
o?
$.fhD
collected, and a food frequency questionnaire was used to
JMM W determine current consumption of dietary sources of antioxidants
'Z |mQZN and use of vitamin supplements.
8sCv]|cn Data management and statistical analysis
{}Za_(Y,] Data were collected either by direct computer entry with a
b_):MQ1{ questionnaire programmed in Paradox© (Carel Corporation,
OUXR Ottawa, Canada) with internal consistency checks, or
DFTyMB1H on self-coding forms. Open-ended responses were coded at
)F2OT<]m, a later time. Data that were entered on the self-coded forms
BF <ikilR were entered into a computer with double data entry and
@ry_nKr9 reconciliation of any inconsistencies. Data range and consistency
*WT`o> checks were performed on the entire data set.
C>w|a SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
B93+BwN>95 employed for statistical analyses.
w1DV\Ap* Ninety-five per cent confidence limits around the agespecific
?I@W:#>o rates were calculated according to Cochran13 to
>e"#'K0?\ account for the effect of the cluster sampling. Ninety-five
VM,]X. per cent confidence limits around age-standardized rates
&JI8]JmU) were calculated according to Breslow and Day.14 The strataspecific
6i~WcAs data were weighted according to the 1996
|H+Wed| Australian Bureau of Statistics census data15 to reflect the
*`RkTcG cataract prevalence in the entire Victorian population.
n=ux5M Univariate analyses with Student’s t-tests and chi-squared
,WB{i^TD tests were first employed to evaluate risk factors for unoperated
ox (%5c)b| cataract. Any factors with P < 0.10 were then fitted
{,~3.5u into a backwards stepwise logistic regression model. For the
& 9
?\b7 Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
KyQX!,rV final multivariate models, P < 0.05 was considered statistically
)TH@#
1 significant. Design effect was assessed through the use
*ppffz of cluster-specific models and multivariate models. The
"!%l/_p? design effect was assumed to be additive and an adjustment
hFl^\$Re made in the variance by adding the variance associated with
1HZO9cXJ the design effect prior to constructing the 95% confidence
'(L7;+E limits.
q(2'\ _`u RESULTS
QW(Mz Hg Study population
V /V9B2.$ A total of 3271 (83%) of the Melbourne residents, 403
?oHpFlj (90%) Melbourne nursing home residents, and 1473 (92%)
<3C*Z"aQ>| rural residents participated. In general, non-participants did
Y#P%6Fy not differ from participants.16 The study population was
v<( representative of the Victorian population and Australia as
.+A+|yR a whole.
&AbNWtCV+G The Melbourne residents ranged in age from 40 to
8&`LYdzt 98 years (mean = 59) and 1511 (46%) were male. The
pohp&Tc
m Melbourne nursing home residents ranged in age from 46 to
S2VA{9:m 101 years (mean = 82) and 85 (21%) were men. The rural
V/I<g residents ranged in age from 40 to 103 years (mean = 60)
S2GxV/E and 701 (47.5%) were men.
9H`XeQ. Prevalence of cataract and prior cataract surgery
0*D$R`$ As would be expected, the rate of any cataract increases
GM f
`A,> dramatically with age (Table 1). The weighted rate of any
Lhb35;\ cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
U7}yi$WT Although the rates varied somewhat between the three
70tH:Z)" strata, they were not significantly different as the 95% confidence
~^fZx5 limits overlapped. The per cent of cataractous eyes
Jgd'1'FOs with best-corrected visual acuity of less than 6/12 was 12.5%
+V046goX W (65/520) for cortical cataract, 18% for nuclear cataract
tm RXgTS (97/534) and 14.4% (27/187) for PSC cataract. Cataract
X296tA>C` surgery also rose dramatically with age. The overall
,,Q O^j]4~ weighted rate of prior cataract surgery in Victoria was
EPM-df!= 3.79% (95% CL 2.97, 4.60) (Table 2).
^sEYOX\ Risk factors for unoperated cataract
{~"/Y@&]R Cases of cataract that had not been removed were classified
]e>w}L(gV as unoperated cataract. Risk factor analyses for unoperated
KD7dye cataract were not performed with the nursing home residents
O6a<`]F as information about risk factor exposure was not
$f=J2&D,Cz available for this cohort. The following factors were assessed
s.N/2F&*W in relation to unoperated cataract: age, sex, residence
tla
5B_ (urban/rural), language spoken at home (a measure of ethnic
# 0Q]dO integration), country of birth, parents’ country of birth (a
)SRefW
.v measure of ethnicity), years since migration, education, use
L<-_1!wh of ophthalmic services, use of optometric services, private
%w
vdn health insurance status, duration of distance glasses use,
Ln<`E|[29 glaucoma, age-related maculopathy and employment status.
Yi+wC}
In this cross sectional study it was not possible to assess the
" H&W}N level of visual acuity that would predict a patient’s having
5Y'qaIFR cataract surgery, as visual acuity data prior to cataract
xH(lm2kvT surgery were not available.
O%zU-_|* The significant risk factors for unoperated cataract in univariate
+wvWwie analyses were related to: whether a participant had
2U\u4NO{ ever seen an optometrist, seen an ophthalmologist or been
mPN@{.(j
diagnosed with glaucoma; and participants’ employment
wQH<gJE/: status (currently employed) and age. These significant
[.'|_l factors were placed in a backwards stepwise logistic regression
3<Zq ]jk?n model. The factors that remained significantly related
1 s2>C!\ to unoperated cataract were whether participants had ever
# 448-8x seen an ophthalmologist, seen an optometrist and been
'}JhzKNj diagnosed with glaucoma. None of the demographic factors
qL&[K>2z were associated with unoperated cataract in the multivariate
W*4-.*U8a model.
rEnQYz The per cent of participants with unoperated cataract
9T}pT{~V who said that they were dissatisfied or very dissatisfied with
X_ cV%# Operated and unoperated cataract in Australia 79
3yY}04[9< Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
/-ch`u md Age group Sex Urban Rural Nursing home Weighted total
{3p4:
*} (years) (%) (%) (%)
1N^[.= 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
ICoHI Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
=wHVsdNCN 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
t#/YN.@r Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
P[#e/qnXu| 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
Ic:(Gi- % Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
}DEg-j,F 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
Gg3,:A_ w Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
Co_A/ 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
[0[i5'K: Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
u+e{Mim 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
v
~?qz5:K~ Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
cAqLE\h Age-standardized
2dcV"lY (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
+z\^t_"f aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
S6M}WR^, their current vision was 30% (290/683), compared with 27%
n;Q7X>-f8` (26/95) of participants with prior cataract surgery (chisquared,
4*#18<u5 1 d.f. = 0.25, P = 0.62).
J+DDh=% Outcomes of cataract surgery
+wU@ynw Two hundred and forty-nine eyes had undergone prior
b:m88AG cataract surgery. Of these 249 operated eyes, 49 (20%) were
[{,T.;'<j left aphakic, 6 (2.4%) had anterior chamber intraocular
L>NL:68yN lenses and 194 (78%) had posterior chamber intraocular
x8\?}UnB lenses. The rate of capsulotomy in the eyes with intact
=sU<S,a* posterior capsules was 36% (73/202). Fifteen per cent of
f4b/NG| eyes (17/114) with a clear posterior capsule had bestcorrected
J T7nG.9 visual acuity of less than 6/12 compared with 43%
0c]/bs{} of eyes (6/14) with opaque capsules, and 15% of eyes
,vawzq[oSy (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
a=1@*ID P = 0.027).
=.U[$~3q% The percentage of eyes with best-corrected visual acuity
Zw9FJ/Zn@ of 6/12 or better was 96% (302/314) for eyes without
beGa#JH, cataract, 88% (1417/1609) for eyes with prevalent cataract
P [ck84F/ and 85% (211/249) for eyes with operated cataract (chisquared,
E \EsWb 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
~2N"#b&J operated eyes (11%) had visual acuities of less than 6/18
8z`G,qh (moderate vision impairment) (Fig. 2). A cause of this
(Q!}9K3 moderate visual impairment (but not the only cause) in four
'n]w"]| (15%) eyes was secondary to cataract surgery. Three of these
F6|]4H.3Q four eyes had undergone intracapsular cataract extraction
EU;9*W< and the fourth eye had an opaque posterior capsule. No one
1{.|+S Z! had bilateral vision impairment as a result of their cataract
!zpRrx_ surgery.
)[IC?U:5I DISCUSSION
XJ\DVZ To our knowledge, this is the first paper to systematically
vWv" assess the prevalence of current cataract, previous cataract
g2ixx+`?|: surgery, predictors of unoperated cataract and the outcomes
hEH?[>9 of cataract surgery in a population-based sample. The Visual
`25yE/ Impairment Project is unique in that the sampling frame and
Vwf$JdK%&l high response rate have ensured that the study population is
H@>` F representative of Australians aged 40 years and over. Therefore,
O+]ZyHnB these data can be used to plan age-related cataract
'KL0@l services throughout Australia.
%OCb:s We found the rate of any cataract in those over the age
ie95rZp of 40 years to be 22%. Although relatively high, this rate is
P|E| $)m significantly less than was reported in a number of previous
FVbb2Y?R studies,2,4,6 with the exception of the Casteldaccia Eye
s^9Voi.y Study.5 However, it is difficult to compare rates of cataract
G~[x
3L' between studies because of different methodologies and
7S:\"A7 cataract definitions employed in the various studies, as well
xm~`7~nFR as the different age structures of the study populations.
\?-<4Bc@ Other studies have used less conservative definitions of
yx[/|nZDC4 cataract, thus leading to higher rates of cataract as defined.
X`K<>0.N In most large epidemiologic studies of cataract, visual acuity
? :%@vM has not been included in the definition of cataract.
}R2u@%n{ Therefore, the prevalence of cataract may not reflect the
!9e=_mY actual need for cataract surgery in the community.
'JE`(xD 80 McCarty et al.
_;y9$"A Table 2. Prevalence of previous cataract by age, gender and cohort
LonxT&"!D Age group Gender Urban Rural Nursing home Weighted total
,[KD,)3y (years) (%) (%) (%)
&r/Mi% 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
V f&zL
Sgr Female 0.00 0.00 0.00 0.00 (
s ll\g 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
'H>^2C iM Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
$a]`nLUa 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
M7~2iU<# Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
8TKnL\aar 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
q3!bky\ Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
.`eN8Dl1 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
T!#GW/? Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
r l% 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
W{+2/P Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
#c!lS<z Age-standardized
$6 f3F?y7 (95% CL) Combined 3.31 (2.70, 3.93) 4.36 (2.67, 6.06) 2.26 (0.82, 3.70) 3.79 (2.97, 4.60)
{!L~@r Figure 2. Visual acuity in eyes that had undergone cataract
_B<X`L
= surgery, n = 249. h, Presenting; j, best-corrected.
n_A3#d<9 Operated and unoperated cataract in Australia 81
H1./x6Hr The weighted prevalence of prior cataract surgery in the
8nV+e~-w Visual Impairment Project (3.6%) was similar to the crude
T8$y[W-c rate in the Beaver Dam Eye Study4 (3.1%), but less than the
g) jYFfGfH crude rate in the Blue Mountains Eye Study6 (6.0%).
)ez9"# MH' However, the age-standardized rate in the Blue Mountains
)Aqtew+A& Eye Study (standardized to the age distribution of the urban
#\m<Sz5Gp# Visual Impairment Project cohort) was found to be less than
ON(kt3.h the Visual Impairment Project (standardized rate = 1.36%,
li.;IWb0+) 95% CL 1.25, 1.47). The incidence of cataract surgery in
q/,O\, Australia has exceeded population growth.1 This is due,
"chDg(jMZ perhaps, to advances in surgical techniques and lens
f-Z/tfC implants that have changed the risk–benefit ratio.
b]KBgZ The Global Initiative for the Elimination of Avoidable
XSLFPTDEc Blindness, sponsored by the World Health Organization,
j#ab_3xH states that cataract surgical services should be provided that
KZf+MSq?
B ‘have a high success rate in terms of visual outcome and
y
m1Y4, improved quality of life’,17 although the ‘high success rate’ is
P*j|.63 not defined. Population- and clinic-based studies conducted
Q=$2c[Uk in the United States have demonstrated marked improvement
3JR+O<3D in visual acuity following cataract surgery.18–20 We
p`qgrI` found that 85% of eyes that had undergone cataract extraction
f!X[c?Xy" had visual acuity of 6/12 or better. Previously, we have
ox.F%)eQ shown that participants with prevalent cataract in this
h<QY5=SF cohort are more likely to express dissatisfaction with their
@6-jgw>W2 current vision than participants without cataract or participants
fk-RV>yr with prior cataract surgery.21 In a national study in the
>vsqG=x United States, researchers found that the change in patients’
:ShT|n7 ratings of their vision difficulties and satisfaction with their
8
z\xrY vision after cataract surgery were more highly related to
#/37V2E their change in visual functioning score than to their change
YS_;OFsd in visual acuity.19 Furthermore, improvement in visual function
WNc0W>*NE1 has been shown to be associated with improvement in
Xch~
1K overall quality of life.22
!;'=iNOYR A recent review found that the incidence of visually
u ^RxD^=L significant posterior capsule opacification following
GC'O[q+ cataract surgery to be greater than 25%.23 We found 36%
[2cD:JL capsulotomy in our population and that this was associated
q5S9C%b with visual acuity similar to that of eyes with a clear
Znv,9- capsule, but significantly better than that of eyes with an
,hmL/K0"(5 opaque capsule.
&%Tj/ Qx A number of studies have shown that the demand and
93
hxSRw timing of cataract surgery vary according to visual acuity,
\73ch degree of handicap and socioeconomic factors.8–10,24,25 We
u]@['
7 have also shown previously that ophthalmologists are more
kcxAd likely to refer a patient for cataract surgery if the patient is
hpk7 Anp employed and less likely to refer a nursing home resident.7
i!Ga5 v8n: In the Visual Impairment Project, we did not find that any
QmIBaMI# particular subgroup of the population was at greater risk of
U/BR*Zn]* having unoperated cataract. Universal access to health care
zdH
kG_PT in Australia may explain the fact that people without
rrv%~giU Medicare are more likely to delay cataract operations in the
rVsJ`+L USA,8 but not having private health insurance is not associated
Y6d@h? ht with unoperated cataract in Australia.
LreP4dRe In summary, cataract is a significant public health problem
BsJC0I( in that one in four people in their 80s will have had cataract
SX-iAS[< surgery. The importance of age-related cataract surgery will
W@!S%Y9 increase further with the ageing of the population: the
Q NVa?'0"Y number of people over age 60 years is expected to double in
wlmRe`R the next 20 years. Cataract surgery services are well
X\F|Tk3_ accessed by the Victorian population and the visual outcomes
~e.L.,4QZ8 of cataract surgery have been shown to be very good.
_wL BA^d^ These data can be used to plan for age-related cataract
lb1Xsgm{ surgical services in Australia in the future as the need for
2GStN74X r cataract extractions increases.
6S\8$ ACKNOWLEDGEMENTS
>@AB<$A The Visual Impairment Project was funded in part by grants
7v_8_K from the Victorian Health Promotion Foundation, the
G
vlS% National Health and Medical Research Council, the Ansell
76` .Y Ophthalmology Foundation, the Dorothy Edols Estate and
5
rUdv}. the Jack Brockhoff Foundation. Dr McCarty is the recipient
o%*xvH*A of a Wagstaff Fellowship in Ophthalmology from the Royal
9]@!S|1 Victorian Eye and Ear Hospital.
1g~R/*Jo REFERENCES
^y4Z+Gu[ 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
.XhrCiZ Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
FNId
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