ABSTRACT
Af~$TyX Purpose: To quantify the prevalence of cataract, the outcomes
kYP#SH/ of cataract surgery and the factors related to
Wq D4YGN unoperated cataract in Australia.
d=$Mim Methods: Participants were recruited from the Visual
`!3SF|x& Impairment Project: a cluster, stratified sample of more than
hn7#
L
5000 Victorians aged 40 years and over. At examination
+/4
A sites interviews, clinical examinations and lens photography
}1L4"}L. were performed. Cataract was defined in participants who
38Mv
25N had: had previous cataract surgery, cortical cataract greater
^,lIK+#Elz than 4/16, nuclear greater than Wilmer standard 2, or
Q",t3i4 posterior subcapsular greater than 1 mm2.
.O5Z8 p Results: The participant group comprised 3271 Melbourne
jh?H.;** residents, 403 Melbourne nursing home residents and 1473
:DK {Vg6 rural residents.The weighted rate of any cataract in Victoria
!]A was 21.5%. The overall weighted rate of prior cataract
^&9zw\x;z surgery was 3.79%. Two hundred and forty-nine eyes had
xk9%F?) had prior cataract surgery. Of these 249 procedures, 49
j1Y~_ (20%) were aphakic, 6 (2.4%) had anterior chamber
XFVE>/H intraocular lenses and 194 (78%) had posterior chamber
y;m| intraocular lenses.Two hundred and eleven of these operated
B{n,t}z eyes (85%) had best-corrected visual acuity of 6/12 or
v ,i%Q$ better, the legal requirement for a driver’s license.Twentyseven
W]$w@.oW[ (11%) had visual acuity of less than 6/18 (moderate
7y'RFD9@{ vision impairment). Complications of cataract surgery
F>SRs=_ caused reduced vision in four of the 27 eyes (15%), or 1.9%
%?1ew of operated eyes. Three of these four eyes had undergone
nmee 'oEw intracapsular cataract extraction and the fourth eye had an
W<h)HhyG opaque posterior capsule. No one had bilateral vision
`z}?"BW| impairment as a result of cataract surgery. Surprisingly, no
ydEoC$?0 particular demographic factors (such as age, gender, rural
rET\n(AJ residence, occupation, employment status, health insurance
7(1|xYCx$ status, ethnicity) were related to the presence of unoperated
MVpGWTH@F cataract.
EgEa1l!NSQ Conclusions: Although the overall prevalence of cataract is
pHGYQ;:L quite high, no particular subgroup is systematically underserviced
~f2z]JLr: in terms of cataract surgery. Overall, the results of
Qab>|eSm cataract surgery are very good, with the majority of eyes
J'6PmPzY| achieving driving vision following cataract extraction.
s2p\]|5 Key words: cataract extraction, health planning, health
5;Czu(iH$ services accessibility, prevalence
+%z>H"J. INTRODUCTION
(Bb5?fw Cataract is the leading cause of blindness worldwide and, in
AG
nxYV"p Australia, cataract extractions account for the majority of all
|u% )gk ophthalmic procedures.1 Over the period 1985–94, the rate
Rxt^v+ ,$ of cataract surgery in Australia was twice as high as would be
F}yW/ expected from the growth in the elderly population.1
[-1^-bb Although there have been a number of studies reporting
h%na>G
the prevalence of cataract in various populations,2–6 there is
&GO}|W little information about determinants of cataract surgery in
<Xhm`rH the population. A previous survey of Australian ophthalmologists
[o#oak{U showed that patient concern and lifestyle, rather
S/hQZHZHg, than visual acuity itself, are the primary factors for referral
`6(S^P for cataract surgery.7 This supports prior research which has
BN5[,J shown that visual acuity is not a strong predictor of need for
h|9L5 cataract surgery.8,9 Elsewhere, socioeconomic status has
\[i1JG been shown to be related to cataract surgery rates.10
CT<7mi! To appropriately plan health care services, information is
fCn^=8KOZ needed about the prevalence of age-related cataract in the
hp
50J community as well as the factors associated with cataract
A0s ZOCky surgery. The purpose of this study is to quantify the prevalence
mfn,Gjt3O of any cataract in Australia, to describe the factors
./Zk`-OBT related to unoperated cataract in the community and to
T@B/xAq5! describe the visual outcomes of cataract surgery.
=%K;X\NB METHODS
:gibfk]C Study population
Y;M|D'y+ Details about the study methodology for the Visual
?pmHFlx Impairment Project have been published previously.11
X=&ET)8-Y Briefly, cluster sampling within three strata was employed to
'3tCH)s recruit subjects aged 40 years and over to participate.
(*'f+R`$ Within the Melbourne Statistical Division, nine pairs of
;(Or`u]Dr census collector districts were randomly selected. Fourteen
DU'`ewLL7 nursing homes within a 5 km radius of these nine test sites
(NU
NHxi5B were randomly chosen to recruit nursing home residents.
Qx#"q'
2 Clinical and Experimental Ophthalmology (2000) 28, 77–82
%p=M; Original Article
~rKrpb]ow Operated and unoperated cataract in Australia
sY Qk Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
j{A y\n( Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
7(8;to6( n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
\'D0'\:vz Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au mR:uj2* 78 McCarty et al.
ZhaP2pC%4 Finally, four pairs of census collector districts in four rural
}q`S$P; Victorian communities were randomly selected to recruit rural
,m:.-iy? residents. A household census was conducted to identify
)9`qG:b' eligible residents aged 40 years and over who had been a
AJ`h9%B resident at that address for at least 6 months. At the time of
vJ[^K the household census, basic information about age, sex,
?M9=yA country of birth, language spoken at home, education, use of
W+?4jwqw corrective spectacles and use of eye care services was collected.
<uw9DU7G Eligible residents were then invited to attend a local
u0c1:Uv#~e examination site for a more detailed interview and examination.
<)c)%'v The study protocol was approved by the Royal Victorian
;))+>%SGCt Eye and Ear Hospital Human Research Ethics Committee.
K!Y71_# Assessment of cataract
y
I A standardized ophthalmic examination was performed after
9F;>
W ET pupil dilatation with one drop of 10% phenylephrine
37.S\gO] hydrochloride. Lens opacities were graded clinically at the
f+)L#>Gl? time of the examination and subsequently from photos using
H3=qe I the Wilmer cataract photo-grading system.12 Cortical and
CXMLt posterior subcapsular (PSC) opacities were assessed on
g@!V3V retroillumination and measured as the proportion (in 1/16)
/{n-Y/jp of pupil circumference occupied by opacity. For this analysis,
aSQ#k;T[ cortical cataract was defined as 4/16 or greater opacity,
LCKV>3+_# PSC cataract was defined as opacity equal to or greater than
PB*&a
YLU 1 mm2 and nuclear cataract was defined as opacity equal to
Ka
V8[|Gn, or greater than Wilmer standard 2,12 independent of visual
16(QR- acuity. Examples of the minimum opacities defined as cortical,
wc4{)qDE nuclear and PSC cataract are presented in Figure 1.
rw JIx|( Bilateral congenital cataracts or cataracts secondary to
flbd0NB intraocular inflammation or trauma were excluded from the
Wt-GjxGi analysis. Two cases of bilateral secondary cataract and eight
iz PDd{[ cases of bilateral congenital cataract were excluded from the
K
Z91- analyses.
/7F:T[ A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
xY(*.T
9K Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
>}i E( height set to an incident angle of 30° was used for examinations.
e6$WQd`O Ektachrome® 200 ASA colour slide film (Eastman
h3
}OX{k Kodak Company, Rochester, NY, USA) was used to photograph
B
W*rIn<?G the nuclear opacities. The cortical opacities were
+iRh photographed with an Oxford® retroillumination camera
JL{VD
/f (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
VuZuS6~#J film (Eastman Kodak). Photographs were graded separately
FWgpnI\X|{ by two research assistants and discrepancies were adjudicated
#.)0xfGW)n by an independent reviewer. Any discrepancies
<R=Zs[9M1 between the clinical grades and the photograph grades were
s9DYi~/, resolved. Except in cases where photographs were missing,
-gX1-,dE the photograph grades were used in the analyses. Photograph
tFOhL9T grades were available for 4301 (84%) for cortical
00~mOK;1 cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
}N6.Uu5zI for PSC cataract. Cataract status was classified according to
cU!vsdR3 the severity of the opacity in the worse eye.
RQ"
,3.R== Assessment of risk factors
^o&. fQ* A standardized questionnaire was used to obtain information
z5*'{t) about education, employment and ethnic background.11
BuXqd[;K% Specific information was elicited on the occurrence, duration
Ne1$ee.NE and treatment of a number of medical conditions,
E""bTz@ including ocular trauma, arthritis, diabetes, gout, hypertension
*#+An<iT ; and mental illness. Information about the use, dose and
3{sVVq5Y duration of tobacco, alcohol, analgesics and steriods were
a~y'RyA collected, and a food frequency questionnaire was used to
G
mA<
g determine current consumption of dietary sources of antioxidants
CryBwm and use of vitamin supplements.
|z^^.d~a0 Data management and statistical analysis
z1X`o Data were collected either by direct computer entry with a
Ok=hT|}Y questionnaire programmed in Paradox© (Carel Corporation,
R.yvjPwJ Ottawa, Canada) with internal consistency checks, or
88wa7i* on self-coding forms. Open-ended responses were coded at
1\I}2; a later time. Data that were entered on the self-coded forms
V1B5w_^>h' were entered into a computer with double data entry and
<x>Mo reconciliation of any inconsistencies. Data range and consistency
Z=vU}S>r|v checks were performed on the entire data set.
FXkM#}RgNm SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
)bscBj@ employed for statistical analyses.
X
UuN )i Ninety-five per cent confidence limits around the agespecific
B
\2SH%\ rates were calculated according to Cochran13 to
GC}==
^1 account for the effect of the cluster sampling. Ninety-five
.3Oap*X per cent confidence limits around age-standardized rates
[Y|t]^M were calculated according to Breslow and Day.14 The strataspecific
2`=7_v data were weighted according to the 1996
dDLeSz$b Australian Bureau of Statistics census data15 to reflect the
ye5&)d"fa( cataract prevalence in the entire Victorian population.
t;\Y{` Univariate analyses with Student’s t-tests and chi-squared
ePo}y])2 tests were first employed to evaluate risk factors for unoperated
O3kA;[f; cataract. Any factors with P < 0.10 were then fitted
X45%e! into a backwards stepwise logistic regression model. For the
8FY?!C Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
-e:`|(Mo final multivariate models, P < 0.05 was considered statistically
6(ol1
(U significant. Design effect was assessed through the use
cSV aI of cluster-specific models and multivariate models. The
s!$7(Q86R design effect was assumed to be additive and an adjustment
f._ua>v,f made in the variance by adding the variance associated with
p0vVkdd the design effect prior to constructing the 95% confidence
:"/d|i`T limits.
97!;.f- RESULTS
-nV9:opD Study population
*0=j?~& A total of 3271 (83%) of the Melbourne residents, 403
/%io+94 (90%) Melbourne nursing home residents, and 1473 (92%)
~Z'?LV<t rural residents participated. In general, non-participants did
qlPT Ll not differ from participants.16 The study population was
[/8%3 representative of the Victorian population and Australia as
0<@
@?G a whole.
g[4WzDF* The Melbourne residents ranged in age from 40 to
kE1TP]| 98 years (mean = 59) and 1511 (46%) were male. The
ncT&Gr Melbourne nursing home residents ranged in age from 46 to
IW] rb/H 101 years (mean = 82) and 85 (21%) were men. The rural
lL0APT; residents ranged in age from 40 to 103 years (mean = 60)
LZxNAua and 701 (47.5%) were men.
7HYwLG:\~ Prevalence of cataract and prior cataract surgery
%d9uTm; As would be expected, the rate of any cataract increases
O?#7N[7 dramatically with age (Table 1). The weighted rate of any
^} >w<'0 cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
ysnx3(+| Although the rates varied somewhat between the three
'i|YlMFIg strata, they were not significantly different as the 95% confidence
M x"\5i limits overlapped. The per cent of cataractous eyes
^E>3|du]O with best-corrected visual acuity of less than 6/12 was 12.5%
+G>\-tjSD (65/520) for cortical cataract, 18% for nuclear cataract
S~G]~g
t (97/534) and 14.4% (27/187) for PSC cataract. Cataract
>9Vn.S surgery also rose dramatically with age. The overall
]7c=PC weighted rate of prior cataract surgery in Victoria was
:NTO03F7v 3.79% (95% CL 2.97, 4.60) (Table 2).
gf\oC> N Risk factors for unoperated cataract
1s;Saq+ Cases of cataract that had not been removed were classified
]A_`0"m.U as unoperated cataract. Risk factor analyses for unoperated
X1_5KH cataract were not performed with the nursing home residents
vtJJ#8a]
as information about risk factor exposure was not
{?7Uj available for this cohort. The following factors were assessed
0JujesUw( in relation to unoperated cataract: age, sex, residence
\o3gKoL% (urban/rural), language spoken at home (a measure of ethnic
KwVbbC3 integration), country of birth, parents’ country of birth (a
V>3X\)qu measure of ethnicity), years since migration, education, use
ChQxa of ophthalmic services, use of optometric services, private
_DEjF)S health insurance status, duration of distance glasses use,
7F.4Ga; glaucoma, age-related maculopathy and employment status.
ql
~J8G9 In this cross sectional study it was not possible to assess the
>y+B level of visual acuity that would predict a patient’s having
fI|$K)K cataract surgery, as visual acuity data prior to cataract
bW+:C5' surgery were not available.
GTxk%
The significant risk factors for unoperated cataract in univariate
9;If&uM analyses were related to: whether a participant had
,<X9Y
2B ever seen an optometrist, seen an ophthalmologist or been
+aAc9'k diagnosed with glaucoma; and participants’ employment
Vi|#@tC' status (currently employed) and age. These significant
EKN~H$. factors were placed in a backwards stepwise logistic regression
uHNCSzH( model. The factors that remained significantly related
MnHNjsO# to unoperated cataract were whether participants had ever
/g.U&oI]D seen an ophthalmologist, seen an optometrist and been
,`sv1xwd diagnosed with glaucoma. None of the demographic factors
$<OD31T were associated with unoperated cataract in the multivariate
)O6>*wq model.
!dT4 The per cent of participants with unoperated cataract
lNv|M)I who said that they were dissatisfied or very dissatisfied with
=i3n42M# Operated and unoperated cataract in Australia 79
{2gwk8 Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
.X;K%J2 Age group Sex Urban Rural Nursing home Weighted total
YchH~m| (years) (%) (%) (%)
[<TrS/,)> 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
f)<6 Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
e~(5%CO>#j 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
o;RI*I Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
,]/X\t5]D 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
:MDKC /mC Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
/<BI46B\ 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
d0 /#nz Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
.o}v#W+st 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
.tr!(O],h Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
#Rr%:\* 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
q75s#[<ap Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
|gY^)9ei Age-standardized
wUM0M?_p[ (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
Q=dy<kg'] aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
ijU*|8n{> their current vision was 30% (290/683), compared with 27%
M"To&?OI (26/95) of participants with prior cataract surgery (chisquared,
rU(+T0t?I 1 d.f. = 0.25, P = 0.62).
'}#9)}x! Outcomes of cataract surgery
UR5`ue ; Two hundred and forty-nine eyes had undergone prior
=H]@n|$( cataract surgery. Of these 249 operated eyes, 49 (20%) were
pI<f) r left aphakic, 6 (2.4%) had anterior chamber intraocular
1yY0dOoLG) lenses and 194 (78%) had posterior chamber intraocular
,9
a lenses. The rate of capsulotomy in the eyes with intact
*DhiN posterior capsules was 36% (73/202). Fifteen per cent of
}SCM I4\ eyes (17/114) with a clear posterior capsule had bestcorrected
Wh{tZ~c visual acuity of less than 6/12 compared with 43%
bi;1s'Y<D of eyes (6/14) with opaque capsules, and 15% of eyes
ht}wEvv (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
DLNbo2C P = 0.027).
~4cC/"q$X The percentage of eyes with best-corrected visual acuity
o*hF<D$Y of 6/12 or better was 96% (302/314) for eyes without
K\c#ig cataract, 88% (1417/1609) for eyes with prevalent cataract
;i+#fQO7Q and 85% (211/249) for eyes with operated cataract (chisquared,
%ULr8)R;
2 d.f. = 22.3), P < 0.001). Twenty-seven of the
SMK_6?MZ operated eyes (11%) had visual acuities of less than 6/18
<p"iY}x[H (moderate vision impairment) (Fig. 2). A cause of this
0_t!T'jr7 moderate visual impairment (but not the only cause) in four
qJUK_6|3 (15%) eyes was secondary to cataract surgery. Three of these
;,e2e
gC' four eyes had undergone intracapsular cataract extraction
DM>eVS3} and the fourth eye had an opaque posterior capsule. No one
c~
V*:$F had bilateral vision impairment as a result of their cataract
u,4eCxYE$ surgery.
JqiP>4Uwm^ DISCUSSION
jW@Uo=I[ To our knowledge, this is the first paper to systematically
$iz|\m assess the prevalence of current cataract, previous cataract
{Y9q[D'g. surgery, predictors of unoperated cataract and the outcomes
lHX72s|V of cataract surgery in a population-based sample. The Visual
AYx{U?0p
Impairment Project is unique in that the sampling frame and
]z9=}=If high response rate have ensured that the study population is
?6Y?a2 | representative of Australians aged 40 years and over. Therefore,
HHsmLo c4 these data can be used to plan age-related cataract
0lR5<^B services throughout Australia.
n.0fVV-A We found the rate of any cataract in those over the age
o"#\
> of 40 years to be 22%. Although relatively high, this rate is
[ibu/W$ significantly less than was reported in a number of previous
wAW5
Z0D studies,2,4,6 with the exception of the Casteldaccia Eye
%bfQ$a: Study.5 However, it is difficult to compare rates of cataract
'."ed%=MC between studies because of different methodologies and
ySDH"|0 cataract definitions employed in the various studies, as well
^r,=vO as the different age structures of the study populations.
)+2hl Other studies have used less conservative definitions of
d-dEQKI?; cataract, thus leading to higher rates of cataract as defined.
e**qF=HCw In most large epidemiologic studies of cataract, visual acuity
|#
2.Q:& has not been included in the definition of cataract.
/
s}}&u/ Therefore, the prevalence of cataract may not reflect the
~M4; actual need for cataract surgery in the community.
6V01F8&w 80 McCarty et al.
;;N9>M?b Table 2. Prevalence of previous cataract by age, gender and cohort
AkQ~k0i}b Age group Gender Urban Rural Nursing home Weighted total
V33T+P~j (years) (%) (%) (%)
N[
Og43Y 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
q5)O%l! Female 0.00 0.00 0.00 0.00 (
[K0(RDV)% 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
YteO6A;
Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
OYTkV}tG 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
^,T(mKS Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
-C?ZB}` 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
bB3powy9 Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
Gu\q%'I 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
7! INkH] Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
{[?(9u7R 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
^sLdAC Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
VQ9/Gxdeo Age-standardized
5uj?#)N (95% CL) Combined 3.31 (2.70, 3.93) 4.36 (2.67, 6.06) 2.26 (0.82, 3.70) 3.79 (2.97, 4.60)
*mvlb
(' & Figure 2. Visual acuity in eyes that had undergone cataract
E92KP?i surgery, n = 249. h, Presenting; j, best-corrected.
ok\vQs(a Operated and unoperated cataract in Australia 81
UJ')I`zuI The weighted prevalence of prior cataract surgery in the
@YTaSz$L Visual Impairment Project (3.6%) was similar to the crude
ML56k~"BL rate in the Beaver Dam Eye Study4 (3.1%), but less than the
^Q? crude rate in the Blue Mountains Eye Study6 (6.0%).
w-L=LWL\ However, the age-standardized rate in the Blue Mountains
3kp+<$ Eye Study (standardized to the age distribution of the urban
;RPx^X~ Visual Impairment Project cohort) was found to be less than
^KT Y? the Visual Impairment Project (standardized rate = 1.36%,
[MM~H0=s 95% CL 1.25, 1.47). The incidence of cataract surgery in
7CURhDdk Australia has exceeded population growth.1 This is due,
e)?
.r9pA; perhaps, to advances in surgical techniques and lens
,Ae6/D$h/ implants that have changed the risk–benefit ratio.
wc^tgE The Global Initiative for the Elimination of Avoidable
0)e\`Bv Blindness, sponsored by the World Health Organization,
~/iKh11 states that cataract surgical services should be provided that
1FL~ndJs ‘have a high success rate in terms of visual outcome and
>7T'OC improved quality of life’,17 although the ‘high success rate’ is
0#Y5_i|p not defined. Population- and clinic-based studies conducted
K)|G0n*qS in the United States have demonstrated marked improvement
i^Y+?Sx in visual acuity following cataract surgery.18–20 We
A>;bHf@ found that 85% of eyes that had undergone cataract extraction
&>W$6>@ had visual acuity of 6/12 or better. Previously, we have
)e=D(qd shown that participants with prevalent cataract in this
' ;FnIZ cohort are more likely to express dissatisfaction with their
E`usknf>l current vision than participants without cataract or participants
_P 3G with prior cataract surgery.21 In a national study in the
SaAFz&WRl United States, researchers found that the change in patients’
3-qr)h ratings of their vision difficulties and satisfaction with their
Ru!iR#s)! vision after cataract surgery were more highly related to
x$.^"l-vX their change in visual functioning score than to their change
U!?_W=? in visual acuity.19 Furthermore, improvement in visual function
6"5A%{J has been shown to be associated with improvement in
qHplJ " overall quality of life.22
S\YTX%Xm} A recent review found that the incidence of visually
%G/hD significant posterior capsule opacification following
lH x^D;m6 cataract surgery to be greater than 25%.23 We found 36%
t?-n*9,#S capsulotomy in our population and that this was associated
j<99FW"@e with visual acuity similar to that of eyes with a clear
BxWPC#5
capsule, but significantly better than that of eyes with an
7cT~oV !G_ opaque capsule.
F^t DL: A number of studies have shown that the demand and
2~1SQ.Q<RY timing of cataract surgery vary according to visual acuity,
oim9<_ degree of handicap and socioeconomic factors.8–10,24,25 We
wOEj)fp. have also shown previously that ophthalmologists are more
3G)#5Lf< likely to refer a patient for cataract surgery if the patient is
RXp
w! employed and less likely to refer a nursing home resident.7
'EEJU/"u In the Visual Impairment Project, we did not find that any
7$vYo
_ particular subgroup of the population was at greater risk of
:0j?oY~e having unoperated cataract. Universal access to health care
['X]R:3h in Australia may explain the fact that people without
x=hiQ>BIO0 Medicare are more likely to delay cataract operations in the
I {S;L USA,8 but not having private health insurance is not associated
G C),N\@Q with unoperated cataract in Australia.
?cBwPetp In summary, cataract is a significant public health problem
av}k)ZT_ in that one in four people in their 80s will have had cataract
SO|NaqWa surgery. The importance of age-related cataract surgery will
@Q
]=\N: increase further with the ageing of the population: the
UqFO|r"M number of people over age 60 years is expected to double in
E"\<s3 the next 20 years. Cataract surgery services are well
-LoZs
ru accessed by the Victorian population and the visual outcomes
rxgbV.tx of cataract surgery have been shown to be very good.
|C;=-| These data can be used to plan for age-related cataract
(Ft+uuG surgical services in Australia in the future as the need for
~drS} V cataract extractions increases.
jH5
k ACKNOWLEDGEMENTS
?mwt~_s9 The Visual Impairment Project was funded in part by grants
-j#2}[J7 from the Victorian Health Promotion Foundation, the
8\@m
- E!{ National Health and Medical Research Council, the Ansell
'%s.^kn Ophthalmology Foundation, the Dorothy Edols Estate and
[i21FX the Jack Brockhoff Foundation. Dr McCarty is the recipient
0rQMLx of a Wagstaff Fellowship in Ophthalmology from the Royal
<.x{|p Victorian Eye and Ear Hospital.
#vz7y(v REFERENCES
y|C(X 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
er("wtM Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
2@n{yYwy 2. Sperduto RD, Hiller R. The prevalence of nuclear, cortical,
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