ABSTRACT
`T9<}&=! Purpose: To quantify the prevalence of cataract, the outcomes
Iz{AA- of cataract surgery and the factors related to
z|P& 8#txM unoperated cataract in Australia.
~[9 ]M)=O0 Methods: Participants were recruited from the Visual
5o~Z> Impairment Project: a cluster, stratified sample of more than
jv0e&rt 5000 Victorians aged 40 years and over. At examination
Eun%uah6c sites interviews, clinical examinations and lens photography
<1jiU%!w were performed. Cataract was defined in participants who
j#p3c had: had previous cataract surgery, cortical cataract greater
nj9hRiLn than 4/16, nuclear greater than Wilmer standard 2, or
&(.ZHF posterior subcapsular greater than 1 mm2.
9) YG)A~< Results: The participant group comprised 3271 Melbourne
v5$zz w residents, 403 Melbourne nursing home residents and 1473
E>V8|Hz; rural residents.The weighted rate of any cataract in Victoria
&FanD
was 21.5%. The overall weighted rate of prior cataract
ng 6G<
hi surgery was 3.79%. Two hundred and forty-nine eyes had
0^[$0]Mt[ had prior cataract surgery. Of these 249 procedures, 49
cA
Lu (20%) were aphakic, 6 (2.4%) had anterior chamber
ja>T nfu intraocular lenses and 194 (78%) had posterior chamber
Lq&xlW
j intraocular lenses.Two hundred and eleven of these operated
l/I W"A eyes (85%) had best-corrected visual acuity of 6/12 or
p' gv5\u[w better, the legal requirement for a driver’s license.Twentyseven
D>1Dao (11%) had visual acuity of less than 6/18 (moderate
0s4j> vision impairment). Complications of cataract surgery
Z2 @&4_P caused reduced vision in four of the 27 eyes (15%), or 1.9%
~|!lC}!IKL of operated eyes. Three of these four eyes had undergone
"{:*fI;! intracapsular cataract extraction and the fourth eye had an
C'$U1%:
j opaque posterior capsule. No one had bilateral vision
u@|yw) impairment as a result of cataract surgery. Surprisingly, no
'\;tmD"N5# particular demographic factors (such as age, gender, rural
[zfGDMG& residence, occupation, employment status, health insurance
1GNAx\( status, ethnicity) were related to the presence of unoperated
s6
^JgdW cataract.
i}YnJ Conclusions: Although the overall prevalence of cataract is
YJ0[BcZ quite high, no particular subgroup is systematically underserviced
> w'6ZDA*X in terms of cataract surgery. Overall, the results of
$pKS['J0 cataract surgery are very good, with the majority of eyes
'F~u \m=E achieving driving vision following cataract extraction.
4H:WpW*r Key words: cataract extraction, health planning, health
e?7paJ services accessibility, prevalence
+1y#=iM{ INTRODUCTION
^Ve^}|qPc Cataract is the leading cause of blindness worldwide and, in
Ob6vg^# Australia, cataract extractions account for the majority of all
~:@H6Ke[ ophthalmic procedures.1 Over the period 1985–94, the rate
f0F$*"#G of cataract surgery in Australia was twice as high as would be
cQR1v-Xt expected from the growth in the elderly population.1
Cr
`
0C Although there have been a number of studies reporting
Vh<`MS0X the prevalence of cataract in various populations,2–6 there is
@K/Ia!
Lw little information about determinants of cataract surgery in
d.Z]R&X08 the population. A previous survey of Australian ophthalmologists
cm]]9z_< showed that patient concern and lifestyle, rather
s*IfXv than visual acuity itself, are the primary factors for referral
jz)H?UuDY for cataract surgery.7 This supports prior research which has
,uv$oP- shown that visual acuity is not a strong predictor of need for
g{%'; cataract surgery.8,9 Elsewhere, socioeconomic status has
@
2mP been shown to be related to cataract surgery rates.10
AUC<
m. To appropriately plan health care services, information is
<%z/6I
Af| needed about the prevalence of age-related cataract in the
>=V+X"\Z community as well as the factors associated with cataract
<} %ir,8 surgery. The purpose of this study is to quantify the prevalence
nR7\ o(! of any cataract in Australia, to describe the factors
a5-\=0L~ related to unoperated cataract in the community and to
MjpJAV/84 describe the visual outcomes of cataract surgery.
Al|7Y/ METHODS
yShHFlO= Study population
R%%`wm
G)" Details about the study methodology for the Visual
}>0
Kc= Impairment Project have been published previously.11
/>C~a]} Briefly, cluster sampling within three strata was employed to
^aXBt recruit subjects aged 40 years and over to participate.
8|({
_Z Within the Melbourne Statistical Division, nine pairs of
PlZiTP census collector districts were randomly selected. Fourteen
yr>bL"!CA nursing homes within a 5 km radius of these nine test sites
Q(UGwd1 were randomly chosen to recruit nursing home residents.
X}(0y
Clinical and Experimental Ophthalmology (2000) 28, 77–82
NJ>p8P`_k Original Article
pr txE&- Operated and unoperated cataract in Australia
H|UL5<:]D Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
$)Yo g]} Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
Db(_T8sU n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
"ILWIzf.] Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au au|^V^m 78 McCarty et al.
Hc]1mM Finally, four pairs of census collector districts in four rural
vLuQe0l{ Victorian communities were randomly selected to recruit rural
@@83PJFid residents. A household census was conducted to identify
%i8>w:@NW eligible residents aged 40 years and over who had been a
,g_onfY resident at that address for at least 6 months. At the time of
</gp3WQ. the household census, basic information about age, sex,
iIaT1i4t. country of birth, language spoken at home, education, use of
^Pd37&B4V corrective spectacles and use of eye care services was collected.
c1kxKxE Eligible residents were then invited to attend a local
A&c@8 examination site for a more detailed interview and examination.
\bm6/fhA: The study protocol was approved by the Royal Victorian
eJw=" Eye and Ear Hospital Human Research Ethics Committee.
`u
h@iD'KI Assessment of cataract
`QdQ?9x{F A standardized ophthalmic examination was performed after
zN+*R;Ds pupil dilatation with one drop of 10% phenylephrine
Pzp+I} hydrochloride. Lens opacities were graded clinically at the
GrR0RwnH)? time of the examination and subsequently from photos using
x$GsDV
the Wilmer cataract photo-grading system.12 Cortical and
yW^IN8fm posterior subcapsular (PSC) opacities were assessed on
o
L Vtu5 retroillumination and measured as the proportion (in 1/16)
R
pI<]1 of pupil circumference occupied by opacity. For this analysis,
\c~{o+UD- cortical cataract was defined as 4/16 or greater opacity,
ouVjZF@kS PSC cataract was defined as opacity equal to or greater than
s!ZW'`4!z 1 mm2 and nuclear cataract was defined as opacity equal to
5 n+
e or greater than Wilmer standard 2,12 independent of visual
ml.;wB| acuity. Examples of the minimum opacities defined as cortical,
eKVALUw nuclear and PSC cataract are presented in Figure 1.
(X(1kj3 Bilateral congenital cataracts or cataracts secondary to
;DD>k bd intraocular inflammation or trauma were excluded from the
pAil]f6 analysis. Two cases of bilateral secondary cataract and eight
d"I28PIS" cases of bilateral congenital cataract were excluded from the
g TXW2S analyses.
a1G9wC:e A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
h zZ-$IX X Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
iog #
, height set to an incident angle of 30° was used for examinations.
:YqQlr\ Ektachrome® 200 ASA colour slide film (Eastman
/z1p/RiX Kodak Company, Rochester, NY, USA) was used to photograph
b+IOh| the nuclear opacities. The cortical opacities were
`u#;MUg photographed with an Oxford® retroillumination camera
*O+R|Cdp/ (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
CYt jY~
film (Eastman Kodak). Photographs were graded separately
Yz=h"Zr by two research assistants and discrepancies were adjudicated
=Y&9
qt by an independent reviewer. Any discrepancies
V)0[`zJ between the clinical grades and the photograph grades were
(@)2PO/ resolved. Except in cases where photographs were missing,
C}mYt/ the photograph grades were used in the analyses. Photograph
Y^R?Q' grades were available for 4301 (84%) for cortical
&so-O90 cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
j-J(C[[9 for PSC cataract. Cataract status was classified according to
|*^8~u3J" the severity of the opacity in the worse eye.
4>4V-m\ Assessment of risk factors
e9CP802#2 A standardized questionnaire was used to obtain information
0A#*4ap about education, employment and ethnic background.11
n1QEu"~Zj Specific information was elicited on the occurrence, duration
R=-+YBw7/ and treatment of a number of medical conditions,
>u=%Lz"J including ocular trauma, arthritis, diabetes, gout, hypertension
I&L.;~ and mental illness. Information about the use, dose and
^Xs%.`Gv/ duration of tobacco, alcohol, analgesics and steriods were
X=v~^8M7% collected, and a food frequency questionnaire was used to
4|[<e-W determine current consumption of dietary sources of antioxidants
NWEhAj<w and use of vitamin supplements.
SQ}S4r Data management and statistical analysis
DH5bpg&T Data were collected either by direct computer entry with a
JOBz{;:R{ questionnaire programmed in Paradox© (Carel Corporation,
!*&4<
_ Ottawa, Canada) with internal consistency checks, or
wJ6_I$> on self-coding forms. Open-ended responses were coded at
-i#J[>=w{C a later time. Data that were entered on the self-coded forms
(tepmcf were entered into a computer with double data entry and
0|g[o:;fl_ reconciliation of any inconsistencies. Data range and consistency
>Q;
g0\
I_ checks were performed on the entire data set.
R7lYu\mA SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
E
W`W~h[ employed for statistical analyses.
Di:{er(p Ninety-five per cent confidence limits around the agespecific
o&~dGG4J rates were calculated according to Cochran13 to
8qn 9| account for the effect of the cluster sampling. Ninety-five
elu=9d];@ per cent confidence limits around age-standardized rates
H"eS<eT were calculated according to Breslow and Day.14 The strataspecific
Hb+X}7c$ data were weighted according to the 1996
j1/+\8Y Australian Bureau of Statistics census data15 to reflect the
/0(%(2jIWl cataract prevalence in the entire Victorian population.
vm8$:W2 } Univariate analyses with Student’s t-tests and chi-squared
vv+km + tests were first employed to evaluate risk factors for unoperated
S_6g~PHsr cataract. Any factors with P < 0.10 were then fitted
9TC)
w| into a backwards stepwise logistic regression model. For the
ioxbf6{ Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
H9U.lb final multivariate models, P < 0.05 was considered statistically
Q^L)
Vp" significant. Design effect was assessed through the use
[
7g>< of cluster-specific models and multivariate models. The
5Tedo~v design effect was assumed to be additive and an adjustment
e4DMO*6 made in the variance by adding the variance associated with
M7rIi\4K4 the design effect prior to constructing the 95% confidence
wjrG7*_Y4v limits.
c
;9.KCpwx RESULTS
sef]>q Study population
yrnv!moc%t A total of 3271 (83%) of the Melbourne residents, 403
X3
',vey (90%) Melbourne nursing home residents, and 1473 (92%)
?F_)- rural residents participated. In general, non-participants did
!J3UqS not differ from participants.16 The study population was
3#c3IZ-; representative of the Victorian population and Australia as
xR?V,uV'$& a whole.
D
<>@
%"% The Melbourne residents ranged in age from 40 to
Be2lMC 98 years (mean = 59) and 1511 (46%) were male. The
MLr-,
"gs Melbourne nursing home residents ranged in age from 46 to
0J9D"3T) 101 years (mean = 82) and 85 (21%) were men. The rural
@ }&_Dvf residents ranged in age from 40 to 103 years (mean = 60)
O6X"RsI} and 701 (47.5%) were men.
=^tA_AxVw Prevalence of cataract and prior cataract surgery
UG](go't As would be expected, the rate of any cataract increases
.X'p q5 dramatically with age (Table 1). The weighted rate of any
JeCg|@ cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
D d,2;#_ Although the rates varied somewhat between the three
w!&
~??&=} strata, they were not significantly different as the 95% confidence
sOpep limits overlapped. The per cent of cataractous eyes
jQ+sn/ROp with best-corrected visual acuity of less than 6/12 was 12.5%
n}?wVfEy (65/520) for cortical cataract, 18% for nuclear cataract
R[jEvyD>( (97/534) and 14.4% (27/187) for PSC cataract. Cataract
%JyXbv3m, surgery also rose dramatically with age. The overall
(V?: ] weighted rate of prior cataract surgery in Victoria was
h@ ) 3.79% (95% CL 2.97, 4.60) (Table 2).
Ii&7rdoxe Risk factors for unoperated cataract
j Ux
z Cases of cataract that had not been removed were classified
gckI.[!b as unoperated cataract. Risk factor analyses for unoperated
`5~3G2T cataract were not performed with the nursing home residents
t#i,1a
HA as information about risk factor exposure was not
~Z'w)!h available for this cohort. The following factors were assessed
3W_PE+:Kr in relation to unoperated cataract: age, sex, residence
om h{0jA0 (urban/rural), language spoken at home (a measure of ethnic
?OlV"zK integration), country of birth, parents’ country of birth (a
>>{FzR measure of ethnicity), years since migration, education, use
.iD*>M:W of ophthalmic services, use of optometric services, private
x1&W^~ health insurance status, duration of distance glasses use,
{0"YOS`3AX glaucoma, age-related maculopathy and employment status.
H1n1-!%d In this cross sectional study it was not possible to assess the
jPZaD>! level of visual acuity that would predict a patient’s having
Xx:F)A8O cataract surgery, as visual acuity data prior to cataract
~@.%m"<. surgery were not available.
f"1>bW>R+ The significant risk factors for unoperated cataract in univariate
%ru;;h analyses were related to: whether a participant had
R:Q0=PzDi# ever seen an optometrist, seen an ophthalmologist or been
4k-+?L!/G diagnosed with glaucoma; and participants’ employment
4;`oUt
'. status (currently employed) and age. These significant
1K,1X(0rL8 factors were placed in a backwards stepwise logistic regression
G)v
#+4 model. The factors that remained significantly related
10!wqyj& to unoperated cataract were whether participants had ever
QTX8
L seen an ophthalmologist, seen an optometrist and been
h\v
'9 diagnosed with glaucoma. None of the demographic factors
I$N8tn+E were associated with unoperated cataract in the multivariate
o*U]v
model.
M" ^PW,k The per cent of participants with unoperated cataract
W@
|6nPm who said that they were dissatisfied or very dissatisfied with
tyaA\F57 Operated and unoperated cataract in Australia 79
;4
N;D Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
-46C!6a Age group Sex Urban Rural Nursing home Weighted total
7$h#OV*@, (years) (%) (%) (%)
4jD2FFG-
G 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
E4m` Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
_uc
hU= 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
g1t0l%_7^ Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
9]q:[zm^ 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
#>Zzf Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
>4t+:Ut: 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
/cU<hApK Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
HRB<Y
mP@ 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
\hCH>*x< Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
As>_J=8} 3 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
w*R$o Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
N<~ku<nAU Age-standardized
S~|T4q( (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
KEWTBBg aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
_4g.j their current vision was 30% (290/683), compared with 27%
K'GBMnjD (26/95) of participants with prior cataract surgery (chisquared,
%n*-VAfE\ 1 d.f. = 0.25, P = 0.62).
yj\Nkh Outcomes of cataract surgery
Qjb:WC7he Two hundred and forty-nine eyes had undergone prior
b9!FC$^J cataract surgery. Of these 249 operated eyes, 49 (20%) were
NU0g07" left aphakic, 6 (2.4%) had anterior chamber intraocular
[sW3l:^ lenses and 194 (78%) had posterior chamber intraocular
A,a.8!*}vd lenses. The rate of capsulotomy in the eyes with intact
"me
n posterior capsules was 36% (73/202). Fifteen per cent of
%\:[ o eyes (17/114) with a clear posterior capsule had bestcorrected
6V7B;tB visual acuity of less than 6/12 compared with 43%
3v1iy/ / of eyes (6/14) with opaque capsules, and 15% of eyes
.N
,3od@ (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
)mF5Vw" P = 0.027).
mjW8Q\D The percentage of eyes with best-corrected visual acuity
4b98KsYg of 6/12 or better was 96% (302/314) for eyes without
J4fi' cataract, 88% (1417/1609) for eyes with prevalent cataract
NTYg[VTr and 85% (211/249) for eyes with operated cataract (chisquared,
m}7iTDJR9 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
X:vghOt? operated eyes (11%) had visual acuities of less than 6/18
P\1L7%*lU (moderate vision impairment) (Fig. 2). A cause of this
^hZ0IM moderate visual impairment (but not the only cause) in four
H|3:6x (15%) eyes was secondary to cataract surgery. Three of these
Vex{.Vh," four eyes had undergone intracapsular cataract extraction
x!5'`A!W% and the fourth eye had an opaque posterior capsule. No one
Rh_np had bilateral vision impairment as a result of their cataract
|}=acc/ surgery.
UQ?XqgUM DISCUSSION
f4 P
8Oz To our knowledge, this is the first paper to systematically
|}BLF assess the prevalence of current cataract, previous cataract
4T|b
Cs?e surgery, predictors of unoperated cataract and the outcomes
Q(wx nm of cataract surgery in a population-based sample. The Visual
p<2L.\6" Impairment Project is unique in that the sampling frame and
gQ Fjr_IS# high response rate have ensured that the study population is
,|y:" s representative of Australians aged 40 years and over. Therefore,
,(qRc(Ho these data can be used to plan age-related cataract
)dbB=OZ services throughout Australia.
j*so9M6|c We found the rate of any cataract in those over the age
ObVGV of 40 years to be 22%. Although relatively high, this rate is
7}f}$1
significantly less than was reported in a number of previous
]zE;Tw.S studies,2,4,6 with the exception of the Casteldaccia Eye
#@YPic"n7` Study.5 However, it is difficult to compare rates of cataract
l{I6&^!KS between studies because of different methodologies and
}vxw*8d? cataract definitions employed in the various studies, as well
q rJ`1 as the different age structures of the study populations.
q
E&v ; Other studies have used less conservative definitions of
dP#|$1 cataract, thus leading to higher rates of cataract as defined.
q)X$^oE!6 In most large epidemiologic studies of cataract, visual acuity
adCU61t has not been included in the definition of cataract.
K28+]qy[ Therefore, the prevalence of cataract may not reflect the
D!{Y$; actual need for cataract surgery in the community.
z>58dA@f 80 McCarty et al.
ciBP7>':: Table 2. Prevalence of previous cataract by age, gender and cohort
Y-kt.X/Z- Age group Gender Urban Rural Nursing home Weighted total
;&<{ey (years) (%) (%) (%)
Oft-w)cYz, 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
7!@-*/|!S9 Female 0.00 0.00 0.00 0.00 (
e@Fo^#ImDx 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
Yw4n-0g Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
D^yRaP*|7 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
0Vlk;fIh Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
ah+~y,Gl 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
zMj#KA1 Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
nxUJN1b!N 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
^T*? >%` Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
jr)1(**
90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
.
<jr0,i Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
|v \_@09= Age-standardized
1n=lqn/ (95% CL) Combined 3.31 (2.70, 3.93) 4.36 (2.67, 6.06) 2.26 (0.82, 3.70) 3.79 (2.97, 4.60)
n!YKz"$ Figure 2. Visual acuity in eyes that had undergone cataract
sF|5XjQ surgery, n = 249. h, Presenting; j, best-corrected.
{K+icTL3 Operated and unoperated cataract in Australia 81
?3nR The weighted prevalence of prior cataract surgery in the
d ^^bke$~ Visual Impairment Project (3.6%) was similar to the crude
kh
{p%<r{ rate in the Beaver Dam Eye Study4 (3.1%), but less than the
HBy[FYa4 crude rate in the Blue Mountains Eye Study6 (6.0%).
NG--6\ However, the age-standardized rate in the Blue Mountains
p2ogn}` Eye Study (standardized to the age distribution of the urban
M$y+q
^ Visual Impairment Project cohort) was found to be less than
uD}2<$PP the Visual Impairment Project (standardized rate = 1.36%,
@OV|]u 95% CL 1.25, 1.47). The incidence of cataract surgery in
tXoWwQD;Y Australia has exceeded population growth.1 This is due,
4i6q{BeHn perhaps, to advances in surgical techniques and lens
rX4j*u2u implants that have changed the risk–benefit ratio.
U7K,AflK?M The Global Initiative for the Elimination of Avoidable
G'oG</A Blindness, sponsored by the World Health Organization,
",
^Mxm{ states that cataract surgical services should be provided that
I%r{]-Obr- ‘have a high success rate in terms of visual outcome and
.LZwuJ^; improved quality of life’,17 although the ‘high success rate’ is
M^O2\G#B not defined. Population- and clinic-based studies conducted
nH`Q#ZFz]? in the United States have demonstrated marked improvement
fI{E SXU in visual acuity following cataract surgery.18–20 We
RZHd9v$ found that 85% of eyes that had undergone cataract extraction
HW=C),*]cR had visual acuity of 6/12 or better. Previously, we have
Ka[t75~; shown that participants with prevalent cataract in this
wj,:"ESb4 cohort are more likely to express dissatisfaction with their
[#l*
_0 current vision than participants without cataract or participants
3
^>l\, with prior cataract surgery.21 In a national study in the
R$q;
! United States, researchers found that the change in patients’
M@`;JjtSA ratings of their vision difficulties and satisfaction with their
ex::m& vision after cataract surgery were more highly related to
+_; l|uhT; their change in visual functioning score than to their change
I,0q4 in visual acuity.19 Furthermore, improvement in visual function
}])oM|fgO has been shown to be associated with improvement in
t/cY=Wp overall quality of life.22
I(V!Mv8j A recent review found that the incidence of visually
S<VSn}vn significant posterior capsule opacification following
^su<uG<R cataract surgery to be greater than 25%.23 We found 36%
z2g3FUTX)b capsulotomy in our population and that this was associated
4Uphfzv3D with visual acuity similar to that of eyes with a clear
r[BVvX/,F capsule, but significantly better than that of eyes with an
H,DM1Z9rz opaque capsule.
]^lw*724'> A number of studies have shown that the demand and
PmK
eF
} timing of cataract surgery vary according to visual acuity,
0\[Chja degree of handicap and socioeconomic factors.8–10,24,25 We
i.3=!6z have also shown previously that ophthalmologists are more
hp#W9@NR likely to refer a patient for cataract surgery if the patient is
7JEbH?lEN employed and less likely to refer a nursing home resident.7
;$smH=I In the Visual Impairment Project, we did not find that any
,q}MLTSi particular subgroup of the population was at greater risk of
sE:M@`2L having unoperated cataract. Universal access to health care
t5y;CxL in Australia may explain the fact that people without
lu<xv Medicare are more likely to delay cataract operations in the
q35f&O; USA,8 but not having private health insurance is not associated
bn!HUM, with unoperated cataract in Australia.
fh](K'P#^ In summary, cataract is a significant public health problem
555XCWyrC in that one in four people in their 80s will have had cataract
sg$rzT-S4 surgery. The importance of age-related cataract surgery will
A-ZN F4 increase further with the ageing of the population: the
gP0LCK> number of people over age 60 years is expected to double in
gBC@38|6) the next 20 years. Cataract surgery services are well
c_vqL$Dl accessed by the Victorian population and the visual outcomes
?d{Na=O\ of cataract surgery have been shown to be very good.
XCU7xi$d These data can be used to plan for age-related cataract
1Cgso` surgical services in Australia in the future as the need for
X!9 B2w cataract extractions increases.
FB{KH . ACKNOWLEDGEMENTS
3'cE\u The Visual Impairment Project was funded in part by grants
s'%R from the Victorian Health Promotion Foundation, the
FVaQEMZ^ National Health and Medical Research Council, the Ansell
L.S;J[a; Ophthalmology Foundation, the Dorothy Edols Estate and
;[=8B\? the Jack Brockhoff Foundation. Dr McCarty is the recipient
{<R2UI5m5 of a Wagstaff Fellowship in Ophthalmology from the Royal
VQ7
*Z5[1 Victorian Eye and Ear Hospital.
j4|N-: REFERENCES
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