ABSTRACT
8r|LFuI Purpose: To quantify the prevalence of cataract, the outcomes
9e=*jRs]l^ of cataract surgery and the factors related to
k@Tt,.]; unoperated cataract in Australia.
*=Fcu@ Methods: Participants were recruited from the Visual
;PHnv5 x@f Impairment Project: a cluster, stratified sample of more than
5cADC`q 5000 Victorians aged 40 years and over. At examination
us cR/d
sites interviews, clinical examinations and lens photography
:U*[s$ were performed. Cataract was defined in participants who
]@P*&FRcZ had: had previous cataract surgery, cortical cataract greater
t}tKm than 4/16, nuclear greater than Wilmer standard 2, or
Mm;)O'XDE posterior subcapsular greater than 1 mm2.
~4^e a Results: The participant group comprised 3271 Melbourne
?4Lo"igAA residents, 403 Melbourne nursing home residents and 1473
4
5lg&oO rural residents.The weighted rate of any cataract in Victoria
+{I\r| was 21.5%. The overall weighted rate of prior cataract
op*+fJHD surgery was 3.79%. Two hundred and forty-nine eyes had
J$Q-1fjj had prior cataract surgery. Of these 249 procedures, 49
)yP>}ME (20%) were aphakic, 6 (2.4%) had anterior chamber
f+6l0@K2 intraocular lenses and 194 (78%) had posterior chamber
m&q;.|W intraocular lenses.Two hundred and eleven of these operated
Cg
Sdyg@ eyes (85%) had best-corrected visual acuity of 6/12 or
xD=D *W better, the legal requirement for a driver’s license.Twentyseven
{dwV-qz (11%) had visual acuity of less than 6/18 (moderate
Lk9>7xY vision impairment). Complications of cataract surgery
6`C27 caused reduced vision in four of the 27 eyes (15%), or 1.9%
WI6E3,ejB1 of operated eyes. Three of these four eyes had undergone
*eP4dGe& intracapsular cataract extraction and the fourth eye had an
]SL&x:/- opaque posterior capsule. No one had bilateral vision
A 5 X+Z impairment as a result of cataract surgery. Surprisingly, no
h+UscdUl particular demographic factors (such as age, gender, rural
`<zb residence, occupation, employment status, health insurance
uKy*N*} status, ethnicity) were related to the presence of unoperated
x]oQl^F cataract.
\6hL W_q1 Conclusions: Although the overall prevalence of cataract is
F9\Ot^~ quite high, no particular subgroup is systematically underserviced
(NdgF+'= in terms of cataract surgery. Overall, the results of
<6C9R> cataract surgery are very good, with the majority of eyes
?+5{HFx achieving driving vision following cataract extraction.
rcx;3Vne Key words: cataract extraction, health planning, health
P|4E1O services accessibility, prevalence
7omGg~!k( INTRODUCTION
0>
=) Cataract is the leading cause of blindness worldwide and, in
?d<:V.1U@ Australia, cataract extractions account for the majority of all
@$d\5Q(G ophthalmic procedures.1 Over the period 1985–94, the rate
"g%:#'5 of cataract surgery in Australia was twice as high as would be
O'-Zn]@.] expected from the growth in the elderly population.1
9K46>_TyH Although there have been a number of studies reporting
F/*fQAa" the prevalence of cataract in various populations,2–6 there is
:ECK
$Cu little information about determinants of cataract surgery in
+){a[@S@x the population. A previous survey of Australian ophthalmologists
;b?+:L showed that patient concern and lifestyle, rather
P9"D[uz than visual acuity itself, are the primary factors for referral
0ITA3v8{ for cataract surgery.7 This supports prior research which has
@P"`=BU& shown that visual acuity is not a strong predictor of need for
5**5b9bj-9 cataract surgery.8,9 Elsewhere, socioeconomic status has
*{dD'9Bg been shown to be related to cataract surgery rates.10
1mn$Rh&dO To appropriately plan health care services, information is
n5k^v$' needed about the prevalence of age-related cataract in the
:+
9Ft> community as well as the factors associated with cataract
,eeL5V surgery. The purpose of this study is to quantify the prevalence
?PE1aB+{: of any cataract in Australia, to describe the factors
;}eEG{`Y related to unoperated cataract in the community and to
m0A@jWgd describe the visual outcomes of cataract surgery.
K~Au?\{
METHODS
J;=aIiN]R Study population
}8V;s-1 Details about the study methodology for the Visual
W|H4i;u Impairment Project have been published previously.11
FJjF*2. Briefly, cluster sampling within three strata was employed to
;h-G3>Il recruit subjects aged 40 years and over to participate.
O5TK&j Within the Melbourne Statistical Division, nine pairs of
)1Ma~8Y%r census collector districts were randomly selected. Fourteen
lYZ@a4TA nursing homes within a 5 km radius of these nine test sites
j |'#5H` were randomly chosen to recruit nursing home residents.
mU?&\w=v$ Clinical and Experimental Ophthalmology (2000) 28, 77–82
UOLTCp?M;J Original Article
E%k ]cZ Operated and unoperated cataract in Australia
yA!3XUi Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
1(:b{Bl Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
p9&gEW n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
G {pP} Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au 7dufY
}} 78 McCarty et al.
mq{$9@3 Finally, four pairs of census collector districts in four rural
6"7:44O;G Victorian communities were randomly selected to recruit rural
zfP[1 residents. A household census was conducted to identify
m0BG9~p| eligible residents aged 40 years and over who had been a
A{
i][1N resident at that address for at least 6 months. At the time of
aR="5{en{: the household census, basic information about age, sex,
, `[Z`SUk` country of birth, language spoken at home, education, use of
_o&, corrective spectacles and use of eye care services was collected.
XDP6T"h Eligible residents were then invited to attend a local
m0%iw1OsH% examination site for a more detailed interview and examination.
w
L/p.@ The study protocol was approved by the Royal Victorian
zH=/.31Q Eye and Ear Hospital Human Research Ethics Committee.
_ bXVg3oDt Assessment of cataract
Yn IM- A standardized ophthalmic examination was performed after
!~lVv&YO pupil dilatation with one drop of 10% phenylephrine
AMh37Xo hydrochloride. Lens opacities were graded clinically at the
AQnJxIL: time of the examination and subsequently from photos using
<?>I\ the Wilmer cataract photo-grading system.12 Cortical and
=RW*
%8C posterior subcapsular (PSC) opacities were assessed on
lQp89*b?=U retroillumination and measured as the proportion (in 1/16)
QoW(tM of pupil circumference occupied by opacity. For this analysis,
27Kc-rcB cortical cataract was defined as 4/16 or greater opacity,
3i]"#wK PSC cataract was defined as opacity equal to or greater than
wE,=%?" 1 mm2 and nuclear cataract was defined as opacity equal to
i$`|Y* or greater than Wilmer standard 2,12 independent of visual
WX%h4)z* acuity. Examples of the minimum opacities defined as cortical,
26\HV nuclear and PSC cataract are presented in Figure 1.
L?3VyBE Bilateral congenital cataracts or cataracts secondary to
lF;ziF intraocular inflammation or trauma were excluded from the
T8,k77 analysis. Two cases of bilateral secondary cataract and eight
'\ph
`Run cases of bilateral congenital cataract were excluded from the
|uQn|"U4 analyses.
!7:EE,W~ A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
q=P
f^Xp Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
S
KB@ height set to an incident angle of 30° was used for examinations.
%-h7Z3YcN Ektachrome® 200 ASA colour slide film (Eastman
D 7Gd% Kodak Company, Rochester, NY, USA) was used to photograph
$Qn&jI38 the nuclear opacities. The cortical opacities were
B8bvp:Ho| photographed with an Oxford® retroillumination camera
w;N{>)hv
(Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
lSZ"y
Q+ film (Eastman Kodak). Photographs were graded separately
K%Usjezv& by two research assistants and discrepancies were adjudicated
.Lr`j8 by an independent reviewer. Any discrepancies
QT`fix{ between the clinical grades and the photograph grades were
#D!$~h&i resolved. Except in cases where photographs were missing,
b*lKT]D, the photograph grades were used in the analyses. Photograph
}U2[? grades were available for 4301 (84%) for cortical
'bLP~ cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
pWMiCXnW for PSC cataract. Cataract status was classified according to
@Djs[Cs<* the severity of the opacity in the worse eye.
PfVEv * Assessment of risk factors
b cC\ A standardized questionnaire was used to obtain information
kFS0i%Sr about education, employment and ethnic background.11
cNdu.c[@ Specific information was elicited on the occurrence, duration
^bF}_CSE and treatment of a number of medical conditions,
M#=Y~PU including ocular trauma, arthritis, diabetes, gout, hypertension
$`^H:Djr and mental illness. Information about the use, dose and
B#J{F duration of tobacco, alcohol, analgesics and steriods were
Bfbl#ZkyL collected, and a food frequency questionnaire was used to
j1'\R+4U determine current consumption of dietary sources of antioxidants
Q]!6uA$A and use of vitamin supplements.
wG_4$kyj Data management and statistical analysis
cB{%u
' Data were collected either by direct computer entry with a
|__d 8a questionnaire programmed in Paradox© (Carel Corporation,
0 9tikj1 Ottawa, Canada) with internal consistency checks, or
!&Z*yH on self-coding forms. Open-ended responses were coded at
A3xbT\xdg a later time. Data that were entered on the self-coded forms
bSQ_" were entered into a computer with double data entry and
"_t4F4z reconciliation of any inconsistencies. Data range and consistency
cvxIp#FbW checks were performed on the entire data set.
',DeP>'%> SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
TV?
^c?{5 employed for statistical analyses.
XnD0eua# Ninety-five per cent confidence limits around the agespecific
%?@x]B9Y8E rates were calculated according to Cochran13 to
yj>){NcX account for the effect of the cluster sampling. Ninety-five
9_eS`,' per cent confidence limits around age-standardized rates
0"hiCGm' were calculated according to Breslow and Day.14 The strataspecific
.Xi2G@D data were weighted according to the 1996
sbzeY1 Australian Bureau of Statistics census data15 to reflect the
n>n"{!
cataract prevalence in the entire Victorian population.
miPmpu! Univariate analyses with Student’s t-tests and chi-squared
P?xA$_+ tests were first employed to evaluate risk factors for unoperated
;jF%bE3 cataract. Any factors with P < 0.10 were then fitted
r9<V%PHv into a backwards stepwise logistic regression model. For the
o94PI*. Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
(:JjQ`i final multivariate models, P < 0.05 was considered statistically
ej<`CQ significant. Design effect was assessed through the use
}N@n{bu+ of cluster-specific models and multivariate models. The
M'YJ" design effect was assumed to be additive and an adjustment
6I"C~&dt made in the variance by adding the variance associated with
Mg+4huT the design effect prior to constructing the 95% confidence
N_0pO<<cs limits.
*aI~W^N3 RESULTS
1}`2\3, Study population
(,shiK[5f A total of 3271 (83%) of the Melbourne residents, 403
Gj)uyjct (90%) Melbourne nursing home residents, and 1473 (92%)
Y^yG/F rural residents participated. In general, non-participants did
yYg not differ from participants.16 The study population was
>C:If0S4X representative of the Victorian population and Australia as
M= atls a whole.
CPVmF$A- The Melbourne residents ranged in age from 40 to
@\!ww/QT 98 years (mean = 59) and 1511 (46%) were male. The
kwOeHdV^ Melbourne nursing home residents ranged in age from 46 to
BK*z 4m 101 years (mean = 82) and 85 (21%) were men. The rural
a/:]"`) residents ranged in age from 40 to 103 years (mean = 60)
;sCU[4 and 701 (47.5%) were men.
0_Lm#fE U Prevalence of cataract and prior cataract surgery
Rh[Ibm56 As would be expected, the rate of any cataract increases
>GmN~"iJ dramatically with age (Table 1). The weighted rate of any
",T`\8&@e cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
>J>>\Y(p Although the rates varied somewhat between the three
i0iez9B
strata, they were not significantly different as the 95% confidence
V'C-'Ythwf limits overlapped. The per cent of cataractous eyes
x_k S
g with best-corrected visual acuity of less than 6/12 was 12.5%
@R UP
$ (65/520) for cortical cataract, 18% for nuclear cataract
J$rJd9t (97/534) and 14.4% (27/187) for PSC cataract. Cataract
R2CQXhiJ surgery also rose dramatically with age. The overall
Fav
^^vf*1 weighted rate of prior cataract surgery in Victoria was
=tnTdp0F 3.79% (95% CL 2.97, 4.60) (Table 2).
m9woredS, Risk factors for unoperated cataract
}I]W'<jY Cases of cataract that had not been removed were classified
GZ"&L?ti as unoperated cataract. Risk factor analyses for unoperated
mbGcDG[HQ cataract were not performed with the nursing home residents
l=xt;c! as information about risk factor exposure was not
bs
BZE available for this cohort. The following factors were assessed
Gnk|^i;t in relation to unoperated cataract: age, sex, residence
>J@egIKzP (urban/rural), language spoken at home (a measure of ethnic
$
o"
L;j integration), country of birth, parents’ country of birth (a
d@Q][7 measure of ethnicity), years since migration, education, use
E23w *'] of ophthalmic services, use of optometric services, private
C38%H health insurance status, duration of distance glasses use,
XGhwrI^ glaucoma, age-related maculopathy and employment status.
St2Q7K5s{ In this cross sectional study it was not possible to assess the
~{P:sjs
U level of visual acuity that would predict a patient’s having
Y1WHy*s? cataract surgery, as visual acuity data prior to cataract
<wa(xDBw surgery were not available.
{@45?L(' The significant risk factors for unoperated cataract in univariate
+9C;<f analyses were related to: whether a participant had
PtqGX=u ever seen an optometrist, seen an ophthalmologist or been
`s%QeAde diagnosed with glaucoma; and participants’ employment
ABZ06S/ status (currently employed) and age. These significant
,VWGq@o% factors were placed in a backwards stepwise logistic regression
O|7yP30?M model. The factors that remained significantly related
ZV(
w to unoperated cataract were whether participants had ever
sUbFRq seen an ophthalmologist, seen an optometrist and been
>XnO&hW diagnosed with glaucoma. None of the demographic factors
8YKQItK were associated with unoperated cataract in the multivariate
K$ AB} Fvc model.
:".w{0l@ The per cent of participants with unoperated cataract
|xeE3,8 who said that they were dissatisfied or very dissatisfied with
uREu2T2 Operated and unoperated cataract in Australia 79
Pr/]0<s Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
S(w\ZC Age group Sex Urban Rural Nursing home Weighted total
<xqba4O (years) (%) (%) (%)
>0T
Za 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
o\goE^,aeR Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
$H;+}VQ 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
gc,Ps Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
!M^\f
N1 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
7kd|K
b( Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
u(2BQO7 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
@ae>b Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
qd8pF!u|# 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
?wCs&tM Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
*<q4S(l 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
Y`^o7'Z2^P Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
h'!V8'}O? Age-standardized
u]bz42] (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)
ET+'Pj3 aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
RUX8qT(Z their current vision was 30% (290/683), compared with 27%
s5AgsMq (26/95) of participants with prior cataract surgery (chisquared,
h[Mdr 1 d.f. = 0.25, P = 0.62).
vi|Zit Outcomes of cataract surgery
n_P(k-^U* Two hundred and forty-nine eyes had undergone prior
+'%\Pr( cataract surgery. Of these 249 operated eyes, 49 (20%) were
GA@ Ue9 left aphakic, 6 (2.4%) had anterior chamber intraocular
wko2M[ lenses and 194 (78%) had posterior chamber intraocular
9-93aC.|} lenses. The rate of capsulotomy in the eyes with intact
GX5W^//} posterior capsules was 36% (73/202). Fifteen per cent of
T V;BNCg eyes (17/114) with a clear posterior capsule had bestcorrected
+?V0:Kz] visual acuity of less than 6/12 compared with 43%
\ 3G*j` of eyes (6/14) with opaque capsules, and 15% of eyes
2d~LNy (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
BKZ v9 P = 0.027).
:kN5?t= The percentage of eyes with best-corrected visual acuity
ETm]o
of 6/12 or better was 96% (302/314) for eyes without
WW6yFriuW cataract, 88% (1417/1609) for eyes with prevalent cataract
yQwVQUW8B and 85% (211/249) for eyes with operated cataract (chisquared,
~p^7X2% ! 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
pL)xqKj operated eyes (11%) had visual acuities of less than 6/18
9[sG1eP! (moderate vision impairment) (Fig. 2). A cause of this
1J'pB;.]s moderate visual impairment (but not the only cause) in four
6w!e?B2/% (15%) eyes was secondary to cataract surgery. Three of these
a2X h>{ four eyes had undergone intracapsular cataract extraction
`j:M)2:*y and the fourth eye had an opaque posterior capsule. No one
}$:#+
(17 had bilateral vision impairment as a result of their cataract
j6og3.H- surgery.
1LyT7h DISCUSSION
Y%h}U<y To our knowledge, this is the first paper to systematically
OHhs y|W assess the prevalence of current cataract, previous cataract
$+TYvA'N surgery, predictors of unoperated cataract and the outcomes
u}m.}Mws of cataract surgery in a population-based sample. The Visual
>b43%^yii Impairment Project is unique in that the sampling frame and
_uJVuCc high response rate have ensured that the study population is
pUhc3L representative of Australians aged 40 years and over. Therefore,
C#$6O8O these data can be used to plan age-related cataract
yZ~b+=UM services throughout Australia.
QPV@'.2m We found the rate of any cataract in those over the age
48k7/w\ of 40 years to be 22%. Although relatively high, this rate is
gDv$DB8- significantly less than was reported in a number of previous
7t3X`db studies,2,4,6 with the exception of the Casteldaccia Eye
N33AcV!*8 Study.5 However, it is difficult to compare rates of cataract
.HCaXFW between studies because of different methodologies and
JaFUcpZk$ cataract definitions employed in the various studies, as well
zHqhl} as the different age structures of the study populations.
FW5}oD(H Other studies have used less conservative definitions of
>|(%2Zl cataract, thus leading to higher rates of cataract as defined.
@`Wt4< In most large epidemiologic studies of cataract, visual acuity
,
02w@we5 has not been included in the definition of cataract.
Oa1'oYIHg Therefore, the prevalence of cataract may not reflect the
Otxa<M+" actual need for cataract surgery in the community.
}+_9"Y
Q: 80 McCarty et al.
hMWo\qM Table 2. Prevalence of previous cataract by age, gender and cohort
-~}
tq] Age group Gender Urban Rural Nursing home Weighted total
o"\{OX (years) (%) (%) (%)
2md.S$V$, 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
MISE C[/ Female 0.00 0.00 0.00 0.00 (
TwUsVM(~ 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
M2L0c? Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
5v+L';wx[T 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
~M; gM]r; Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
vU{jda$$# 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
a-:pJE.'p Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
@'Q%Jc( 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
cPJ7E Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
{IrJLlq
90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
4/f[`].#W Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
5Fh8*8u6hL Age-standardized
SKW;MVC (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)
^7<[}u;qF Figure 2. Visual acuity in eyes that had undergone cataract
l:x_j\ surgery, n = 249. h, Presenting; j, best-corrected.
g/!Otgfu Operated and unoperated cataract in Australia 81
mgxz1d The weighted prevalence of prior cataract surgery in the
v/x*]c!"` Visual Impairment Project (3.6%) was similar to the crude
u,\xok" rate in the Beaver Dam Eye Study4 (3.1%), but less than the
RpjSTV8Tkm crude rate in the Blue Mountains Eye Study6 (6.0%).
&%}bRPUl However, the age-standardized rate in the Blue Mountains
v23TL Eye Study (standardized to the age distribution of the urban
_En]@xK3& Visual Impairment Project cohort) was found to be less than
kv/(rKLp* the Visual Impairment Project (standardized rate = 1.36%,
K/~Y!?:Jr 95% CL 1.25, 1.47). The incidence of cataract surgery in
GgT=t)}wu Australia has exceeded population growth.1 This is due,
6S)$3Is perhaps, to advances in surgical techniques and lens
f7S^yA[[ implants that have changed the risk–benefit ratio.
|^Ur The Global Initiative for the Elimination of Avoidable
tjt=N\; Blindness, sponsored by the World Health Organization,
`9:v*KuM#R states that cataract surgical services should be provided that
KzIt ‘have a high success rate in terms of visual outcome and
yB|]LYh improved quality of life’,17 although the ‘high success rate’ is
p
FXd4* not defined. Population- and clinic-based studies conducted
)ynA:LXx in the United States have demonstrated marked improvement
ocq2 in visual acuity following cataract surgery.18–20 We
Y7*'QKz2 found that 85% of eyes that had undergone cataract extraction
xu`d`!Tx had visual acuity of 6/12 or better. Previously, we have
S[ws0Y60 shown that participants with prevalent cataract in this
DS.39NY cohort are more likely to express dissatisfaction with their
2lX[hFa5 current vision than participants without cataract or participants
\YjB+[. with prior cataract surgery.21 In a national study in the
S.qk%NTTD United States, researchers found that the change in patients’
=%:JjgKc*t ratings of their vision difficulties and satisfaction with their
i=,B88ko vision after cataract surgery were more highly related to
p,3go[9X:R their change in visual functioning score than to their change
B:.;,@r] in visual acuity.19 Furthermore, improvement in visual function
>OF:"_fh has been shown to be associated with improvement in
olUqBQ&ol overall quality of life.22
S7@ZtFf A recent review found that the incidence of visually
j+z' significant posterior capsule opacification following
o06A=4I cataract surgery to be greater than 25%.23 We found 36%
AH"g^ gw~T capsulotomy in our population and that this was associated
HV#?6,U} with visual acuity similar to that of eyes with a clear
Pu/-Qpqh capsule, but significantly better than that of eyes with an
yVu^
> opaque capsule.
0KWy?6 X A number of studies have shown that the demand and
F^/~@^{P timing of cataract surgery vary according to visual acuity,
[R@q]S/ degree of handicap and socioeconomic factors.8–10,24,25 We
GU;TK'Yy? have also shown previously that ophthalmologists are more
*il]$i likely to refer a patient for cataract surgery if the patient is
\N'hbT= employed and less likely to refer a nursing home resident.7
ZmYa.4'L In the Visual Impairment Project, we did not find that any
F3H:I"4 particular subgroup of the population was at greater risk of
:N+K^gI) having unoperated cataract. Universal access to health care
!ch[I#&J- in Australia may explain the fact that people without
#XYLVee, Medicare are more likely to delay cataract operations in the
: .FfE USA,8 but not having private health insurance is not associated
[Ls2k&)0 with unoperated cataract in Australia.
2>_brz|7:| In summary, cataract is a significant public health problem
qxg7cj2 in that one in four people in their 80s will have had cataract
Uy_}@50"l surgery. The importance of age-related cataract surgery will
3;-@<9 increase further with the ageing of the population: the
&t9XK8S number of people over age 60 years is expected to double in
+r#=n7t the next 20 years. Cataract surgery services are well
#1,>Qnl accessed by the Victorian population and the visual outcomes
!4b;>y=m of cataract surgery have been shown to be very good.
cfy/*| These data can be used to plan for age-related cataract
5,=B
1 surgical services in Australia in the future as the need for
#:Sy`G6!? cataract extractions increases.
!lt\2A
e ACKNOWLEDGEMENTS
|=h)efo} The Visual Impairment Project was funded in part by grants
M~g~LhsF from the Victorian Health Promotion Foundation, the
fjK]m.w National Health and Medical Research Council, the Ansell
7}iewtdy, Ophthalmology Foundation, the Dorothy Edols Estate and
5LhJ8$W the Jack Brockhoff Foundation. Dr McCarty is the recipient
9B?t3: of a Wagstaff Fellowship in Ophthalmology from the Royal
BF1O|Q|d6 Victorian Eye and Ear Hospital.
#G4~]Qml REFERENCES
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D0E"YEo\nv Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
>Wr 2. Sperduto RD, Hiller R. The prevalence of nuclear, cortical,
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