ABSTRACT
Lc<eRVNd, Purpose: To quantify the prevalence of cataract, the outcomes
[ neXFp}S of cataract surgery and the factors related to
J
NC unoperated cataract in Australia.
Wv!<bT8r Methods: Participants were recruited from the Visual
"`A :(<x Impairment Project: a cluster, stratified sample of more than
4ZT A> 5000 Victorians aged 40 years and over. At examination
1xnLB>jP# sites interviews, clinical examinations and lens photography
l{P\No were performed. Cataract was defined in participants who
h5|.Et had: had previous cataract surgery, cortical cataract greater
F5gObIJtuY than 4/16, nuclear greater than Wilmer standard 2, or
>
s*Drf X6 posterior subcapsular greater than 1 mm2.
<64HveJ Results: The participant group comprised 3271 Melbourne
BOf1J1 residents, 403 Melbourne nursing home residents and 1473
5 HV)[us rural residents.The weighted rate of any cataract in Victoria
w#G2-?aj was 21.5%. The overall weighted rate of prior cataract
kpfwqHT surgery was 3.79%. Two hundred and forty-nine eyes had
[JTto!Ih$ had prior cataract surgery. Of these 249 procedures, 49
Uhh
l3%p (20%) were aphakic, 6 (2.4%) had anterior chamber
^9"KTZc-* intraocular lenses and 194 (78%) had posterior chamber
>tRHNB_ intraocular lenses.Two hundred and eleven of these operated
00vBpsZj2; eyes (85%) had best-corrected visual acuity of 6/12 or
qFRdg V>8 better, the legal requirement for a driver’s license.Twentyseven
,ul5,ygA (11%) had visual acuity of less than 6/18 (moderate
M<8ML!N0;t vision impairment). Complications of cataract surgery
{_ V0 caused reduced vision in four of the 27 eyes (15%), or 1.9%
u@ N~1@RT| of operated eyes. Three of these four eyes had undergone
(L69{n intracapsular cataract extraction and the fourth eye had an
u>cC O'q opaque posterior capsule. No one had bilateral vision
vahoSc;sw impairment as a result of cataract surgery. Surprisingly, no
p6 xPheD particular demographic factors (such as age, gender, rural
|w)5;uQ&\ residence, occupation, employment status, health insurance
!G=>v
e status, ethnicity) were related to the presence of unoperated
<O857j cataract.
V7<eQ0;m
Conclusions: Although the overall prevalence of cataract is
k
'zat3#f quite high, no particular subgroup is systematically underserviced
\aSz2lxEHn in terms of cataract surgery. Overall, the results of
T |"`8mG cataract surgery are very good, with the majority of eyes
juno.$
6 achieving driving vision following cataract extraction.
cx(2jk}6 Key words: cataract extraction, health planning, health
$B _Nc*_e services accessibility, prevalence
fGu!M9qN4 INTRODUCTION
8$~3r a Cataract is the leading cause of blindness worldwide and, in
<f%/px%1 Australia, cataract extractions account for the majority of all
W);W.:F ophthalmic procedures.1 Over the period 1985–94, the rate
ePA;:8)_j of cataract surgery in Australia was twice as high as would be
P/aDd@j expected from the growth in the elderly population.1
zl)&U=4l Although there have been a number of studies reporting
ba&o;BLUy the prevalence of cataract in various populations,2–6 there is
$%He$t little information about determinants of cataract surgery in
p {C9`wi) the population. A previous survey of Australian ophthalmologists
>h7$v~nra showed that patient concern and lifestyle, rather
Bcaw~WD than visual acuity itself, are the primary factors for referral
AN10U;p/O for cataract surgery.7 This supports prior research which has
U"x~Jb3]O shown that visual acuity is not a strong predictor of need for
qy9i9$8 cataract surgery.8,9 Elsewhere, socioeconomic status has
b`]M|C [5 been shown to be related to cataract surgery rates.10
eBvW#Hzp To appropriately plan health care services, information is
k`@w(HhS needed about the prevalence of age-related cataract in the
?#ihJt, community as well as the factors associated with cataract
)k~1, surgery. The purpose of this study is to quantify the prevalence
@LC~*_y of any cataract in Australia, to describe the factors
`,m7xJZ?y related to unoperated cataract in the community and to
MiD describe the visual outcomes of cataract surgery.
J!<#Nc METHODS
O\JD, w Study population
w`-$-4i Details about the study methodology for the Visual
TU-c9"7M~ Impairment Project have been published previously.11
%^U"Spv; Briefly, cluster sampling within three strata was employed to
oVEAlBm^v recruit subjects aged 40 years and over to participate.
x
Ty7lfSe Within the Melbourne Statistical Division, nine pairs of
qAORWc census collector districts were randomly selected. Fourteen
xv&S[=Dt nursing homes within a 5 km radius of these nine test sites
##2`5i-x were randomly chosen to recruit nursing home residents.
i :EO(` Clinical and Experimental Ophthalmology (2000) 28, 77–82
R(GmU4 Original Article
j $0zD:ppW Operated and unoperated cataract in Australia
? KF=W Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
6~3jn+K$1 Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
*LEu=3lp%> n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
XK3!V|y` Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au -B,c B 78 McCarty et al.
{9Xm<}%u]] Finally, four pairs of census collector districts in four rural
)*Vj3Jx Victorian communities were randomly selected to recruit rural
J$#D:KaU:N residents. A household census was conducted to identify
niQ+EAD eligible residents aged 40 years and over who had been a
eL_^: - resident at that address for at least 6 months. At the time of
"B~WcC the household census, basic information about age, sex,
4 *H(sq country of birth, language spoken at home, education, use of
G~`'E&/ corrective spectacles and use of eye care services was collected.
@OY1`EuO Eligible residents were then invited to attend a local
i'Wcf1I-= examination site for a more detailed interview and examination.
K_Z+]]$# The study protocol was approved by the Royal Victorian
7t`E@dm Eye and Ear Hospital Human Research Ethics Committee.
(y
3~[ Assessment of cataract
F68},N>vr@ A standardized ophthalmic examination was performed after
:ao^/&HZ pupil dilatation with one drop of 10% phenylephrine
HE@-uh hydrochloride. Lens opacities were graded clinically at the
}+*w.X
}L time of the examination and subsequently from photos using
SQKi2\8w the Wilmer cataract photo-grading system.12 Cortical and
u"*J[M~ posterior subcapsular (PSC) opacities were assessed on
=A$Lgk>| retroillumination and measured as the proportion (in 1/16)
V/@[%w= of pupil circumference occupied by opacity. For this analysis,
@
;g`+:= cortical cataract was defined as 4/16 or greater opacity,
=kwb`
Z/a PSC cataract was defined as opacity equal to or greater than
3L?WTS6(u 1 mm2 and nuclear cataract was defined as opacity equal to
CQj/e+eE4 or greater than Wilmer standard 2,12 independent of visual
F1 9;RaP+ acuity. Examples of the minimum opacities defined as cortical,
CM`x>J nuclear and PSC cataract are presented in Figure 1.
OY+!aG@. Bilateral congenital cataracts or cataracts secondary to
2;dM:FHLhO intraocular inflammation or trauma were excluded from the
@gs26jX~2} analysis. Two cases of bilateral secondary cataract and eight
UEN YJ*tnP cases of bilateral congenital cataract were excluded from the
rat=)n)"t analyses.
BT&rp%NO6l A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
M|1eqR%x-? Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
s'R~r height set to an incident angle of 30° was used for examinations.
9` OG Ektachrome® 200 ASA colour slide film (Eastman
jK&
Nkp Kodak Company, Rochester, NY, USA) was used to photograph
.a
~s_E the nuclear opacities. The cortical opacities were
e@='Q H photographed with an Oxford® retroillumination camera
_Jf J%YXy (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
$ iX^p4v film (Eastman Kodak). Photographs were graded separately
OI)&vQ5k by two research assistants and discrepancies were adjudicated
Ej;Vr~Wi by an independent reviewer. Any discrepancies
d)`nxnbMeM between the clinical grades and the photograph grades were
trID#DT~ resolved. Except in cases where photographs were missing,
>VpP/Qf the photograph grades were used in the analyses. Photograph
c@0l-R{q grades were available for 4301 (84%) for cortical
q$e
T!'x cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
dbf^A1HI for PSC cataract. Cataract status was classified according to
!Ei Ze.K the severity of the opacity in the worse eye.
44Seq Assessment of risk factors
T
{5
M1r A standardized questionnaire was used to obtain information
@c.11nfn` about education, employment and ethnic background.11
YHwVj?6W Specific information was elicited on the occurrence, duration
umq$4}T'$ and treatment of a number of medical conditions,
T>AI
0R3 including ocular trauma, arthritis, diabetes, gout, hypertension
,*9#c*'S and mental illness. Information about the use, dose and
<MI$Nl duration of tobacco, alcohol, analgesics and steriods were
r9p?@P\:[ collected, and a food frequency questionnaire was used to
LH?gJ8` determine current consumption of dietary sources of antioxidants
+iZ@.LI and use of vitamin supplements.
.HH,l Data management and statistical analysis
yKX:Z4I/ Data were collected either by direct computer entry with a
s5_1}KKCs questionnaire programmed in Paradox© (Carel Corporation,
g/n"N>L Ottawa, Canada) with internal consistency checks, or
8ESk
G on self-coding forms. Open-ended responses were coded at
-7C=- \]
a later time. Data that were entered on the self-coded forms
Z.cG`Km* were entered into a computer with double data entry and
y$;zTH_6j reconciliation of any inconsistencies. Data range and consistency
b_)QBE9 checks were performed on the entire data set.
0*]<RM SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
<+mO$0h"r employed for statistical analyses.
U3VsMV*Y Ninety-five per cent confidence limits around the agespecific
6i?kkULBS rates were calculated according to Cochran13 to
unbcz{&Hb[ account for the effect of the cluster sampling. Ninety-five
R, (+NT$ per cent confidence limits around age-standardized rates
CM@"lV_ were calculated according to Breslow and Day.14 The strataspecific
ni 02N3R data were weighted according to the 1996
O7L6Htya Australian Bureau of Statistics census data15 to reflect the
:` !mCW`Q- cataract prevalence in the entire Victorian population.
G1n>@Y'j'' Univariate analyses with Student’s t-tests and chi-squared
O+3D
5* tests were first employed to evaluate risk factors for unoperated
'E4(!H,k cataract. Any factors with P < 0.10 were then fitted
@?($j)9} into a backwards stepwise logistic regression model. For the
0 ^-b} Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
"p_[A final multivariate models, P < 0.05 was considered statistically
E Zu significant. Design effect was assessed through the use
s
$=B~l of cluster-specific models and multivariate models. The
v*T@<]f3j design effect was assumed to be additive and an adjustment
h^3Vd K, made in the variance by adding the variance associated with
T=)L5 Vuq< the design effect prior to constructing the 95% confidence
H6+st`{ limits.
Yh!\:9@( RESULTS
M. UUA?d<' Study population
{UjIxV(J A total of 3271 (83%) of the Melbourne residents, 403
Q0oDl8~ (90%) Melbourne nursing home residents, and 1473 (92%)
s9)8{z rural residents participated. In general, non-participants did
:O2v0Kx not differ from participants.16 The study population was
?2
O-EiWjZ representative of the Victorian population and Australia as
,HjHt\!~< a whole.
z8MpE The Melbourne residents ranged in age from 40 to
m~\m"zJ4 98 years (mean = 59) and 1511 (46%) were male. The
-1Ki7|0, Melbourne nursing home residents ranged in age from 46 to
SZ1pf#w! 101 years (mean = 82) and 85 (21%) were men. The rural
4?6'~G$k residents ranged in age from 40 to 103 years (mean = 60)
pRfHbPV? and 701 (47.5%) were men.
.m
% x-i Prevalence of cataract and prior cataract surgery
n$VPh/ As would be expected, the rate of any cataract increases
NhaeAD
$e dramatically with age (Table 1). The weighted rate of any
9hi(P*%q cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
>Sl:Z ,g; Although the rates varied somewhat between the three
y#SD-#I- strata, they were not significantly different as the 95% confidence
N,'qMoNf limits overlapped. The per cent of cataractous eyes
5EZr"[8M with best-corrected visual acuity of less than 6/12 was 12.5%
qv >( (65/520) for cortical cataract, 18% for nuclear cataract
vnT
(97/534) and 14.4% (27/187) for PSC cataract. Cataract
?@7|Q/ surgery also rose dramatically with age. The overall
o ML
K!]a weighted rate of prior cataract surgery in Victoria was
hQrsZv:Q
3.79% (95% CL 2.97, 4.60) (Table 2).
5^R#e(mr Risk factors for unoperated cataract
mCP +7q7 Cases of cataract that had not been removed were classified
eh#
(}v as unoperated cataract. Risk factor analyses for unoperated
i}12mjF cataract were not performed with the nursing home residents
xH.q as information about risk factor exposure was not
*fyEw\`a available for this cohort. The following factors were assessed
E8
V\J in relation to unoperated cataract: age, sex, residence
}E]&13>r (urban/rural), language spoken at home (a measure of ethnic
mr\L q~*c integration), country of birth, parents’ country of birth (a
Nd!=3W5? measure of ethnicity), years since migration, education, use
8&iI+\lCy of ophthalmic services, use of optometric services, private
Yl3PZ*#@ Q health insurance status, duration of distance glasses use,
/-9+( glaucoma, age-related maculopathy and employment status.
@Pg@ltUd
In this cross sectional study it was not possible to assess the
H s 3*OhK\ level of visual acuity that would predict a patient’s having
6>^k9cJp cataract surgery, as visual acuity data prior to cataract
H%jIjf surgery were not available.
x@l~*6!K The significant risk factors for unoperated cataract in univariate
$CV'p/^En analyses were related to: whether a participant had
n Fn`>kQ ever seen an optometrist, seen an ophthalmologist or been
8xz7S diagnosed with glaucoma; and participants’ employment
s: .XF|e{ status (currently employed) and age. These significant
{; ~i
q factors were placed in a backwards stepwise logistic regression
u $^`hzfI model. The factors that remained significantly related
c.> (/ to unoperated cataract were whether participants had ever
ZOsn,nF seen an ophthalmologist, seen an optometrist and been
C\h<02 diagnosed with glaucoma. None of the demographic factors
NGzqiu"J were associated with unoperated cataract in the multivariate
!~kzxY model.
Kt0Tuj@CY The per cent of participants with unoperated cataract
BGj
Ta.& who said that they were dissatisfied or very dissatisfied with
nA
j2k Operated and unoperated cataract in Australia 79
&g {_.n, Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
p-Btbhv Age group Sex Urban Rural Nursing home Weighted total
N#ObxOE6T" (years) (%) (%) (%)
VG7#6)sQoK 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
h}_q Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
Xqw7lj;K 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
bS6Yi)p Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
vRs5-T 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
C_)>VP
D Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
u{z{3fW_ 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
oPBjsQ Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
xnO
lV 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
&o.SmkJI Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
|SleSgS<# 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
kMXl
{ Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
bS<p dOX_ Age-standardized
@9a=D<'> (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)
h='=uj8o5 aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
4r&~=up] their current vision was 30% (290/683), compared with 27%
89bKnsV (26/95) of participants with prior cataract surgery (chisquared,
^eii
4 1 d.f. = 0.25, P = 0.62).
IgL8u Outcomes of cataract surgery
"
cg>g/ Two hundred and forty-nine eyes had undergone prior
K%;yFEZ cataract surgery. Of these 249 operated eyes, 49 (20%) were
Is[0ri left aphakic, 6 (2.4%) had anterior chamber intraocular
%b9M\ lenses and 194 (78%) had posterior chamber intraocular
aT #|mk=\ lenses. The rate of capsulotomy in the eyes with intact
3OlY Ml posterior capsules was 36% (73/202). Fifteen per cent of
rv:O|wZ eyes (17/114) with a clear posterior capsule had bestcorrected
b
v "S( visual acuity of less than 6/12 compared with 43%
c
lNP9{ of eyes (6/14) with opaque capsules, and 15% of eyes
QR4o j (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
Tx_LH"8 P = 0.027).
V5+a[`] The percentage of eyes with best-corrected visual acuity
`u-Y 5mY of 6/12 or better was 96% (302/314) for eyes without
6%-2G@
6d cataract, 88% (1417/1609) for eyes with prevalent cataract
rH,N.H#] and 85% (211/249) for eyes with operated cataract (chisquared,
Yi`.zm 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
566EMy|
operated eyes (11%) had visual acuities of less than 6/18
&n|gPp77$ (moderate vision impairment) (Fig. 2). A cause of this
jk
@]d5 moderate visual impairment (but not the only cause) in four
^_uzr}LE` (15%) eyes was secondary to cataract surgery. Three of these
]CjODa four eyes had undergone intracapsular cataract extraction
$)3/N&GXR and the fourth eye had an opaque posterior capsule. No one
?jbam!A had bilateral vision impairment as a result of their cataract
R[QE:#hT surgery.
0W)_5f& DISCUSSION
sdLFBiR To our knowledge, this is the first paper to systematically
6x 0>E^~ assess the prevalence of current cataract, previous cataract
;
OsN^ surgery, predictors of unoperated cataract and the outcomes
(ZYOm of cataract surgery in a population-based sample. The Visual
ag6S"IXh Impairment Project is unique in that the sampling frame and
zv41Yv!x} high response rate have ensured that the study population is
/bWV`* representative of Australians aged 40 years and over. Therefore,
08Q:1 ' these data can be used to plan age-related cataract
0*q:p`OLw* services throughout Australia.
.#X0P= We found the rate of any cataract in those over the age
[7bY( of 40 years to be 22%. Although relatively high, this rate is
2}NfR8
N significantly less than was reported in a number of previous
A)xI.Q6 studies,2,4,6 with the exception of the Casteldaccia Eye
q9OIw1xQr* Study.5 However, it is difficult to compare rates of cataract
xsfq[}eH< between studies because of different methodologies and
hm&~6rB cataract definitions employed in the various studies, as well
_Qv4;a as the different age structures of the study populations.
;j$84o{ Other studies have used less conservative definitions of
E_++yK^= cataract, thus leading to higher rates of cataract as defined.
vjHbg#0 % In most large epidemiologic studies of cataract, visual acuity
RR"#z'zQ has not been included in the definition of cataract.
p'H5yg3h Therefore, the prevalence of cataract may not reflect the
xe5>)\18- actual need for cataract surgery in the community.
? f%@8%px 80 McCarty et al.
3}"VUS0wh Table 2. Prevalence of previous cataract by age, gender and cohort
U9JqZ! Age group Gender Urban Rural Nursing home Weighted total
b^ v.FK46G (years) (%) (%) (%)
3LEN~N} 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
l!oU9 Female 0.00 0.00 0.00 0.00 (
Cnn,$R=/s 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
"MyYu}AD Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
* 6uiOtH 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
&oT]ycz% Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
mk[n3oE1 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
y_\d[ Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
Ngg (<ZN 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
d~.#K S Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
3 iY`
kf 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
#*~#t4S- Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
r>
NgJf, Age-standardized
`AYHCn (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)
zhFGMF1 Figure 2. Visual acuity in eyes that had undergone cataract
Wt_@ vs@.O surgery, n = 249. h, Presenting; j, best-corrected.
6Z
7{|B5}Y Operated and unoperated cataract in Australia 81
dD#A.C,Rz The weighted prevalence of prior cataract surgery in the
42Z2Mjtk Visual Impairment Project (3.6%) was similar to the crude
XWK A0 rate in the Beaver Dam Eye Study4 (3.1%), but less than the
Y@Ty_j~ crude rate in the Blue Mountains Eye Study6 (6.0%).
\vKMNk;kz However, the age-standardized rate in the Blue Mountains
[03Aej Eye Study (standardized to the age distribution of the urban
|',MgA Visual Impairment Project cohort) was found to be less than
xaejG/'iK the Visual Impairment Project (standardized rate = 1.36%,
{D$#m 95% CL 1.25, 1.47). The incidence of cataract surgery in
$n!saPpxS Australia has exceeded population growth.1 This is due,
"4|D"|w
I) perhaps, to advances in surgical techniques and lens
X&pK#= implants that have changed the risk–benefit ratio.
d_]zX;_ The Global Initiative for the Elimination of Avoidable
3
`$- Blindness, sponsored by the World Health Organization,
)mS
Aog< states that cataract surgical services should be provided that
YR^J7b\ ‘have a high success rate in terms of visual outcome and
N
vQN improved quality of life’,17 although the ‘high success rate’ is
GeD^-.^ not defined. Population- and clinic-based studies conducted
)u`q41! in the United States have demonstrated marked improvement
iO~3rWQ in visual acuity following cataract surgery.18–20 We
0ERA(=w5 found that 85% of eyes that had undergone cataract extraction
*xI0hFJIM had visual acuity of 6/12 or better. Previously, we have
|1uyJ?%B shown that participants with prevalent cataract in this
s sUWr=mD cohort are more likely to express dissatisfaction with their
7='lu;=, current vision than participants without cataract or participants
^
9UKsy/q with prior cataract surgery.21 In a national study in the
Tq,Kel United States, researchers found that the change in patients’
ozy~`$;c ratings of their vision difficulties and satisfaction with their
fucG 9B vision after cataract surgery were more highly related to
6w|s1!Bl their change in visual functioning score than to their change
W_8N?coM in visual acuity.19 Furthermore, improvement in visual function
b*&AIiT has been shown to be associated with improvement in
XvETys@d overall quality of life.22
-|YG**i/ A recent review found that the incidence of visually
n** W significant posterior capsule opacification following
LVP2jTz cataract surgery to be greater than 25%.23 We found 36%
DybuLB$f capsulotomy in our population and that this was associated
~-ZquJ- with visual acuity similar to that of eyes with a clear
p8,Rr{ capsule, but significantly better than that of eyes with an
5+Fr/C opaque capsule.
^h\& l{e
A number of studies have shown that the demand and
v"ZNS timing of cataract surgery vary according to visual acuity,
i[_B~/_ degree of handicap and socioeconomic factors.8–10,24,25 We
[ @
>}
have also shown previously that ophthalmologists are more
a|S6r-_;s likely to refer a patient for cataract surgery if the patient is
v,]-;V
~< employed and less likely to refer a nursing home resident.7
F#NuZ'U In the Visual Impairment Project, we did not find that any
NhJ]X cfP8 particular subgroup of the population was at greater risk of
;GQCq@)- having unoperated cataract. Universal access to health care
F/
p/&9 in Australia may explain the fact that people without
,^wjtA3j8 Medicare are more likely to delay cataract operations in the
hvW FzT5 USA,8 but not having private health insurance is not associated
8_$[SV$q with unoperated cataract in Australia.
JX!z,X?r4 In summary, cataract is a significant public health problem
b:B+x6M in that one in four people in their 80s will have had cataract
cPunMHD surgery. The importance of age-related cataract surgery will
zD^*->`p increase further with the ageing of the population: the
D*=.;Rq number of people over age 60 years is expected to double in
'k'"+ the next 20 years. Cataract surgery services are well
J(>T&G; accessed by the Victorian population and the visual outcomes
^k J>4 of cataract surgery have been shown to be very good.
Yw(O}U 5e These data can be used to plan for age-related cataract
kF]sy8u]
surgical services in Australia in the future as the need for
,{6Vf|? cataract extractions increases.
<S ae:m4 ACKNOWLEDGEMENTS
Uv
) B The Visual Impairment Project was funded in part by grants
qt{lZ_$ from the Victorian Health Promotion Foundation, the
G22{',#r8 National Health and Medical Research Council, the Ansell
8&Md=ZvK` Ophthalmology Foundation, the Dorothy Edols Estate and
*q&^tn b the Jack Brockhoff Foundation. Dr McCarty is the recipient
]A&pXAM of a Wagstaff Fellowship in Ophthalmology from the Royal
+-r ~-b s Victorian Eye and Ear Hospital.
N?EeT}m _ REFERENCES
gWD46+A){ 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
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