ABSTRACT
xB(:d'1| Purpose: To quantify the prevalence of cataract, the outcomes
K|G$s of cataract surgery and the factors related to
YP<]f>SBt unoperated cataract in Australia.
%-l:_A Methods: Participants were recruited from the Visual
"AouiZkh Impairment Project: a cluster, stratified sample of more than
WO-WoPO 5000 Victorians aged 40 years and over. At examination
!7)ID7d sites interviews, clinical examinations and lens photography
u =kSs were performed. Cataract was defined in participants who
ge?-^s4M had: had previous cataract surgery, cortical cataract greater
l~YNmmv _ than 4/16, nuclear greater than Wilmer standard 2, or
Z]TVH8%|k posterior subcapsular greater than 1 mm2.
? SP7v
Q/ Results: The participant group comprised 3271 Melbourne
*'YNRM\} residents, 403 Melbourne nursing home residents and 1473
23$hwr&G\ rural residents.The weighted rate of any cataract in Victoria
0juIkN# was 21.5%. The overall weighted rate of prior cataract
)95yV;n surgery was 3.79%. Two hundred and forty-nine eyes had
+g6j=% had prior cataract surgery. Of these 249 procedures, 49
o:DBOpS (20%) were aphakic, 6 (2.4%) had anterior chamber
0t/y~TrBY intraocular lenses and 194 (78%) had posterior chamber
rg^\BUa-W, intraocular lenses.Two hundred and eleven of these operated
Gd6 ;'ZCmY eyes (85%) had best-corrected visual acuity of 6/12 or
,DuZMGg better, the legal requirement for a driver’s license.Twentyseven
M(zY[O (11%) had visual acuity of less than 6/18 (moderate
ilp;@O6 vision impairment). Complications of cataract surgery
d)1sP0Z_@ caused reduced vision in four of the 27 eyes (15%), or 1.9%
/Np"J of operated eyes. Three of these four eyes had undergone
O;BMwg_7 intracapsular cataract extraction and the fourth eye had an
K'5sn|) opaque posterior capsule. No one had bilateral vision
{9.~]dI|L impairment as a result of cataract surgery. Surprisingly, no
Ed&,[rC particular demographic factors (such as age, gender, rural
'"]>`=R residence, occupation, employment status, health insurance
Q`p}X&^a status, ethnicity) were related to the presence of unoperated
?sf2h:\N cataract.
wdcryejCkr Conclusions: Although the overall prevalence of cataract is
z@l!\m- quite high, no particular subgroup is systematically underserviced
\LoSUl
i in terms of cataract surgery. Overall, the results of
a[P>SqT4` cataract surgery are very good, with the majority of eyes
Q$.V:# achieving driving vision following cataract extraction.
llaZP(pJ Key words: cataract extraction, health planning, health
wO_pcNYZ8 services accessibility, prevalence
iVpA@p INTRODUCTION
kf^-m/ Cataract is the leading cause of blindness worldwide and, in
f}lT|.)?VD Australia, cataract extractions account for the majority of all
{GX
&)c4 ophthalmic procedures.1 Over the period 1985–94, the rate
?`T6CRZhr of cataract surgery in Australia was twice as high as would be
}W@#S_-e8 expected from the growth in the elderly population.1
lNA'M& Although there have been a number of studies reporting
ND e[2 the prevalence of cataract in various populations,2–6 there is
N.5KPAvg% little information about determinants of cataract surgery in
s`B
e#v the population. A previous survey of Australian ophthalmologists
6cQeL$,SQ showed that patient concern and lifestyle, rather
j:v~MrQ7| than visual acuity itself, are the primary factors for referral
y?*[}S for cataract surgery.7 This supports prior research which has
<@U. shown that visual acuity is not a strong predictor of need for
9*-pden
l cataract surgery.8,9 Elsewhere, socioeconomic status has
=qV4Sje|q been shown to be related to cataract surgery rates.10
;<bj{#mMv To appropriately plan health care services, information is
"q9~C needed about the prevalence of age-related cataract in the
>}dTO/ community as well as the factors associated with cataract
hapB! ~M? surgery. The purpose of this study is to quantify the prevalence
w&wA >q>& of any cataract in Australia, to describe the factors
;PfeP;z related to unoperated cataract in the community and to
SZim
>@R describe the visual outcomes of cataract surgery.
?Kx6Sf<i METHODS
_"?c9 Study population
TRs[ ~K)n Details about the study methodology for the Visual
`DgaO-Dg3 Impairment Project have been published previously.11
Fe_::NVvk Briefly, cluster sampling within three strata was employed to
_L&n
&y1+% recruit subjects aged 40 years and over to participate.
it
qQ)\W Within the Melbourne Statistical Division, nine pairs of
763E 6,7 census collector districts were randomly selected. Fourteen
#d}0}7ue nursing homes within a 5 km radius of these nine test sites
4)3g!o? were randomly chosen to recruit nursing home residents.
b\SXZN)Be Clinical and Experimental Ophthalmology (2000) 28, 77–82
/M0l
p Original Article
~mN g[] Operated and unoperated cataract in Australia
r5f^WZ$- Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
R<0Fy =z Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
k-{yu8*'; n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
Jy]FrSm^ Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au >}-~rZ 78 McCarty et al.
%)zk..K{l Finally, four pairs of census collector districts in four rural
U8 Z~Y}29 Victorian communities were randomly selected to recruit rural
Q{H17]W residents. A household census was conducted to identify
$-m@KB eligible residents aged 40 years and over who had been a
}BA9Ka#% resident at that address for at least 6 months. At the time of
KjO-0VMN3 the household census, basic information about age, sex,
+2-
qlU country of birth, language spoken at home, education, use of
}$^]dn@ corrective spectacles and use of eye care services was collected.
9Tqo LX Eligible residents were then invited to attend a local
pI
&o?n examination site for a more detailed interview and examination.
!A~d[</]m The study protocol was approved by the Royal Victorian
66/Z\H^d Eye and Ear Hospital Human Research Ethics Committee.
<#zwKTmK1 Assessment of cataract
`tX@8| A standardized ophthalmic examination was performed after
L{!ihJr pupil dilatation with one drop of 10% phenylephrine
PXa5g5! hydrochloride. Lens opacities were graded clinically at the
nlaG<L# time of the examination and subsequently from photos using
:=y0'f
V(@ the Wilmer cataract photo-grading system.12 Cortical and
R_7
6W& posterior subcapsular (PSC) opacities were assessed on
vuXS/ d retroillumination and measured as the proportion (in 1/16)
>o#ERNf of pupil circumference occupied by opacity. For this analysis,
[ne"
T cortical cataract was defined as 4/16 or greater opacity,
Np$z%ewK. PSC cataract was defined as opacity equal to or greater than
?<!
n
m&~ 1 mm2 and nuclear cataract was defined as opacity equal to
>'N!dM.+9 or greater than Wilmer standard 2,12 independent of visual
C>4UbU acuity. Examples of the minimum opacities defined as cortical,
-/zp&*0gcx nuclear and PSC cataract are presented in Figure 1.
IJ0#iA. T Bilateral congenital cataracts or cataracts secondary to
MA$Xv`6I\ intraocular inflammation or trauma were excluded from the
oKRFd_r +
analysis. Two cases of bilateral secondary cataract and eight
%MbyKz:X cases of bilateral congenital cataract were excluded from the
D;
jK/2 analyses.
@ ICbKg: A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
Y87XLvig} Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
}a ^|L"
height set to an incident angle of 30° was used for examinations.
x/xb1" Ektachrome® 200 ASA colour slide film (Eastman
~,gLplpG0 Kodak Company, Rochester, NY, USA) was used to photograph
LQqfi
~ the nuclear opacities. The cortical opacities were
3{e'YD~hP photographed with an Oxford® retroillumination camera
w4,]2Ccn. (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
+I@cO&CY| film (Eastman Kodak). Photographs were graded separately
U-g9C. by two research assistants and discrepancies were adjudicated
@\jQoaLT$_ by an independent reviewer. Any discrepancies
4H-j
.|e between the clinical grades and the photograph grades were
.,M;huRg resolved. Except in cases where photographs were missing,
c+2sT3).D the photograph grades were used in the analyses. Photograph
DsGI/c grades were available for 4301 (84%) for cortical
g<a<*)& cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
8W -@N for PSC cataract. Cataract status was classified according to
pj;
I)-d/ the severity of the opacity in the worse eye.
]Ik%#l.G_ Assessment of risk factors
X#ZgS!Mn A standardized questionnaire was used to obtain information
7ZsA5%s=, about education, employment and ethnic background.11
3?`" Specific information was elicited on the occurrence, duration
,2,5Odrz and treatment of a number of medical conditions,
S
GM!#K including ocular trauma, arthritis, diabetes, gout, hypertension
B4Lx{uno and mental illness. Information about the use, dose and
8\#
^k#X duration of tobacco, alcohol, analgesics and steriods were
H~o <AmE0! collected, and a food frequency questionnaire was used to
~pz FZ7n4 determine current consumption of dietary sources of antioxidants
_~M^ uW^l and use of vitamin supplements.
2"&)
W dm Data management and statistical analysis
Ik
~1:D]f Data were collected either by direct computer entry with a
zwr\:Hu4 questionnaire programmed in Paradox© (Carel Corporation,
n:4uA`Vg Ottawa, Canada) with internal consistency checks, or
>EP(~G3u on self-coding forms. Open-ended responses were coded at
=SBBvnPLI a later time. Data that were entered on the self-coded forms
,Z~;U were entered into a computer with double data entry and
Uyx&E?SlEq reconciliation of any inconsistencies. Data range and consistency
2UadV_s+s checks were performed on the entire data set.
1-VT}J( SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
Em^(
employed for statistical analyses.
_[K#O,D, Ninety-five per cent confidence limits around the agespecific
'2nqHX
D rates were calculated according to Cochran13 to
ziEz.Wn" account for the effect of the cluster sampling. Ninety-five
Y(6Sp'0 per cent confidence limits around age-standardized rates
0 f/.>1M= were calculated according to Breslow and Day.14 The strataspecific
RBGX_v? data were weighted according to the 1996
G/?~\
}:s
Australian Bureau of Statistics census data15 to reflect the
-?a<qa?$ cataract prevalence in the entire Victorian population.
P?ep] Univariate analyses with Student’s t-tests and chi-squared
e@]Wh)
tests were first employed to evaluate risk factors for unoperated
K_BPZ5w cataract. Any factors with P < 0.10 were then fitted
Mz=!w]qDH into a backwards stepwise logistic regression model. For the
m7qqY
Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
=zg:aTMti final multivariate models, P < 0.05 was considered statistically
0b|zk < significant. Design effect was assessed through the use
u{f*
M,k of cluster-specific models and multivariate models. The
wts:65~ design effect was assumed to be additive and an adjustment
k#JQxLy# made in the variance by adding the variance associated with
2#5,MP~r the design effect prior to constructing the 95% confidence
}
:?.># limits.
wz
/GB8P RESULTS
i+vsp@d Study population
\gO,hST A total of 3271 (83%) of the Melbourne residents, 403
@,H9zrjVFZ (90%) Melbourne nursing home residents, and 1473 (92%)
JBX[bx52<r rural residents participated. In general, non-participants did
(
(3}LQ not differ from participants.16 The study population was
1yqoA* representative of the Victorian population and Australia as
2y GOzc a whole.
f@V3\Z/6E The Melbourne residents ranged in age from 40 to
3smM,fi 98 years (mean = 59) and 1511 (46%) were male. The
P9Q2gVGAO{ Melbourne nursing home residents ranged in age from 46 to
^>$P)=O:v 101 years (mean = 82) and 85 (21%) were men. The rural
t-e5ld~a residents ranged in age from 40 to 103 years (mean = 60)
'\ DSTr:N and 701 (47.5%) were men.
&<x@1, Prevalence of cataract and prior cataract surgery
pxINw>
\Qv As would be expected, the rate of any cataract increases
`k{& /] dramatically with age (Table 1). The weighted rate of any
$.mQ7XDA9 cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
R4's7k Although the rates varied somewhat between the three
||B;o- strata, they were not significantly different as the 95% confidence
-7]Xjb5 limits overlapped. The per cent of cataractous eyes
OyG"1F with best-corrected visual acuity of less than 6/12 was 12.5%
hP@(6X," (65/520) for cortical cataract, 18% for nuclear cataract
jFG0`n}I (97/534) and 14.4% (27/187) for PSC cataract. Cataract
!>^JSHR4t surgery also rose dramatically with age. The overall
vP-M,4c weighted rate of prior cataract surgery in Victoria was
/uqu32;o 3.79% (95% CL 2.97, 4.60) (Table 2).
}OShT+xeX Risk factors for unoperated cataract
Bstk{&ew Cases of cataract that had not been removed were classified
3ha|0[r9 as unoperated cataract. Risk factor analyses for unoperated
_sHK*&W{CT cataract were not performed with the nursing home residents
ZFh+x@ as information about risk factor exposure was not
r8M Zvm2 available for this cohort. The following factors were assessed
wVK*P
-C in relation to unoperated cataract: age, sex, residence
'md0] R| (urban/rural), language spoken at home (a measure of ethnic
),^eA integration), country of birth, parents’ country of birth (a
1' w:`/_ measure of ethnicity), years since migration, education, use
|?m` xO of ophthalmic services, use of optometric services, private
/)|X.D health insurance status, duration of distance glasses use,
Eh8Pwt7C@ glaucoma, age-related maculopathy and employment status.
>%b\yl%0 In this cross sectional study it was not possible to assess the
jB$SUO`* level of visual acuity that would predict a patient’s having
1cN')" cataract surgery, as visual acuity data prior to cataract
"u^EleE! surgery were not available.
8}p8r|d!ls The significant risk factors for unoperated cataract in univariate
Rhgj&4 analyses were related to: whether a participant had
.#6MQJ]OH ever seen an optometrist, seen an ophthalmologist or been
'%iPVHK7 diagnosed with glaucoma; and participants’ employment
|WQ9a' ' status (currently employed) and age. These significant
".2K9j7$ factors were placed in a backwards stepwise logistic regression
=jAFgwP\ model. The factors that remained significantly related
2OBfHO~D to unoperated cataract were whether participants had ever
eb:A1f4L seen an ophthalmologist, seen an optometrist and been
BR_TykP diagnosed with glaucoma. None of the demographic factors
S\C*iGeqJ were associated with unoperated cataract in the multivariate
)najO*n model.
Pe7e?79 The per cent of participants with unoperated cataract
1i
|.h who said that they were dissatisfied or very dissatisfied with
v"6 \=@ Operated and unoperated cataract in Australia 79
S'i;xL> Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
P_4DGW Age group Sex Urban Rural Nursing home Weighted total
v"lf-c
(years) (%) (%) (%)
ur%$aX) 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
440FhDMj Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
Fz"ff4Bx [ 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
:[7lTp
Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
ocA]M=3~k 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
:hqZPajE Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
a|qsQ'1,; 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
<4X
?EYaTq Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
nB@UKX 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
! q6hC Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
g`Md80*Zfk 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
"dCzWFet Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
4O$2]D.\ Age-standardized
*8A6Q9YT (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
BQrL7y aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
-Zy)5NB-tZ their current vision was 30% (290/683), compared with 27%
"sbBe73 m (26/95) of participants with prior cataract surgery (chisquared,
L(o#4YH}>J 1 d.f. = 0.25, P = 0.62).
qu{mqkfN> Outcomes of cataract surgery
3 wt Two hundred and forty-nine eyes had undergone prior
~"7J}[i5 cataract surgery. Of these 249 operated eyes, 49 (20%) were
)/Y~6
A9> left aphakic, 6 (2.4%) had anterior chamber intraocular
k|j:T[_ lenses and 194 (78%) had posterior chamber intraocular
*\q8BZ lenses. The rate of capsulotomy in the eyes with intact
}~zO+Wf2 posterior capsules was 36% (73/202). Fifteen per cent of
xqWj|jA eyes (17/114) with a clear posterior capsule had bestcorrected
6VR[)T% visual acuity of less than 6/12 compared with 43%
E+{5-[Zc*$ of eyes (6/14) with opaque capsules, and 15% of eyes
Bl4 dhBZoO (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
otnV-7)@ P = 0.027).
Phlk1*1n
The percentage of eyes with best-corrected visual acuity
WOb8"*OM of 6/12 or better was 96% (302/314) for eyes without
7^wE$7hS cataract, 88% (1417/1609) for eyes with prevalent cataract
Iw
RQL% and 85% (211/249) for eyes with operated cataract (chisquared,
A2_Ls;] 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
jtLnj@, operated eyes (11%) had visual acuities of less than 6/18
taV|YP$ (moderate vision impairment) (Fig. 2). A cause of this
t|=n1\=? moderate visual impairment (but not the only cause) in four
*`.LA@bHU (15%) eyes was secondary to cataract surgery. Three of these
j
kCH
i@ four eyes had undergone intracapsular cataract extraction
dqz1xQ1 and the fourth eye had an opaque posterior capsule. No one
o16~l]Z|f had bilateral vision impairment as a result of their cataract
E7LbSZ surgery.
">,K1:(D DISCUSSION
lb95!.av+I To our knowledge, this is the first paper to systematically
d'q&Lq assess the prevalence of current cataract, previous cataract
+7^w9G surgery, predictors of unoperated cataract and the outcomes
#:I^&~:
of cataract surgery in a population-based sample. The Visual
U,d2DAvt Impairment Project is unique in that the sampling frame and
V^WQ6G1 high response rate have ensured that the study population is
Ks51:M representative of Australians aged 40 years and over. Therefore,
1sMV`qv> these data can be used to plan age-related cataract
/rOnm=P+Q services throughout Australia.
)2toL5 Q We found the rate of any cataract in those over the age
wvX"D0eVn of 40 years to be 22%. Although relatively high, this rate is
hsz$S:am significantly less than was reported in a number of previous
uiuTv)pwF studies,2,4,6 with the exception of the Casteldaccia Eye
yq!CWXZ2 Study.5 However, it is difficult to compare rates of cataract
qjzZ} between studies because of different methodologies and
j}"]s/= 6 cataract definitions employed in the various studies, as well
:nt}7Dn' as the different age structures of the study populations.
01-p
`H+ Other studies have used less conservative definitions of
rrbZ+*U cataract, thus leading to higher rates of cataract as defined.
F6~b#Jz&i In most large epidemiologic studies of cataract, visual acuity
QZWoKGd}+ has not been included in the definition of cataract.
Q4#\{" N! Therefore, the prevalence of cataract may not reflect the
ST#PMb'izn actual need for cataract surgery in the community.
ws#hhW3qK 80 McCarty et al.
zj%cd; Table 2. Prevalence of previous cataract by age, gender and cohort
twAw01". Age group Gender Urban Rural Nursing home Weighted total
)x y9X0 (years) (%) (%) (%)
"pR $cS 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
F>p%2II/ Female 0.00 0.00 0.00 0.00 (
AX/=}G 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
:Xb*m85y Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
rD_Ss.\^g 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
;]|m((15G Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
9t,aT!f 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
lv*Wnn@k Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
Lx9hq7< 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
# Lu4OSM+ Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
[RroHXdk+ 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
5;r({J Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
w; yar=n Age-standardized
#MmmwPB_ (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)
,:\zXESy4 Figure 2. Visual acuity in eyes that had undergone cataract
5<0Yh#_ surgery, n = 249. h, Presenting; j, best-corrected.
n:%'{}Jw Operated and unoperated cataract in Australia 81
% t,1_c0w The weighted prevalence of prior cataract surgery in the
}[YcilU_ Visual Impairment Project (3.6%) was similar to the crude
x`&P}4v0 rate in the Beaver Dam Eye Study4 (3.1%), but less than the
FuRn%)DA5 crude rate in the Blue Mountains Eye Study6 (6.0%).
*R1d4|/G However, the age-standardized rate in the Blue Mountains
+LvZ87O^~ Eye Study (standardized to the age distribution of the urban
GcU(:V2o Visual Impairment Project cohort) was found to be less than
k;9#4^4( the Visual Impairment Project (standardized rate = 1.36%,
@)FXG~C* 95% CL 1.25, 1.47). The incidence of cataract surgery in
p)AvG; Australia has exceeded population growth.1 This is due,
c"jhbH!u4 perhaps, to advances in surgical techniques and lens
Lt
ZWs0l0 implants that have changed the risk–benefit ratio.
)Q N=>J The Global Initiative for the Elimination of Avoidable
}pU!
1GsO Blindness, sponsored by the World Health Organization,
*PA1iNdKS states that cataract surgical services should be provided that
_16&K}< ‘have a high success rate in terms of visual outcome and
U~QCN[gh improved quality of life’,17 although the ‘high success rate’ is
?PH}b?f4 not defined. Population- and clinic-based studies conducted
:D)&>{? in the United States have demonstrated marked improvement
%d~9at6-B in visual acuity following cataract surgery.18–20 We
m$G?e9{ found that 85% of eyes that had undergone cataract extraction
]((
>i%%~ had visual acuity of 6/12 or better. Previously, we have
uR[PKLh shown that participants with prevalent cataract in this
vo^9qSX
f cohort are more likely to express dissatisfaction with their
3C5D~9v current vision than participants without cataract or participants
[n@
!=T with prior cataract surgery.21 In a national study in the
\/e*quxx United States, researchers found that the change in patients’
J7aK3he ratings of their vision difficulties and satisfaction with their
$9u vision after cataract surgery were more highly related to
DcvmeGl their change in visual functioning score than to their change
jn3|9x in visual acuity.19 Furthermore, improvement in visual function
"oGM>@q=B has been shown to be associated with improvement in
frO/
nx|9 overall quality of life.22
GeW$lA I A recent review found that the incidence of visually
W1,L>Az^Ts significant posterior capsule opacification following
="nrq
&2 cataract surgery to be greater than 25%.23 We found 36%
Xcpm?aTo capsulotomy in our population and that this was associated
&JQ@(w with visual acuity similar to that of eyes with a clear
K*i1! "w capsule, but significantly better than that of eyes with an
<$Kv^Y * opaque capsule.
UA u4x 7 A number of studies have shown that the demand and
~rfjQPbh9x timing of cataract surgery vary according to visual acuity,
sNpBTG@{l degree of handicap and socioeconomic factors.8–10,24,25 We
uM6!RR!~ have also shown previously that ophthalmologists are more
') cgx9 likely to refer a patient for cataract surgery if the patient is
;Z~.54Pf{d employed and less likely to refer a nursing home resident.7
3tcsj0Rb In the Visual Impairment Project, we did not find that any
\@t5S particular subgroup of the population was at greater risk of
a~TZ9yg+HL having unoperated cataract. Universal access to health care
*^5,7}9Qo in Australia may explain the fact that people without
)GKgK;=~ Medicare are more likely to delay cataract operations in the
BfLZ USA,8 but not having private health insurance is not associated
!27]1%Aw with unoperated cataract in Australia.
?YykCJJ ~@ In summary, cataract is a significant public health problem
qP'g}Pc in that one in four people in their 80s will have had cataract
JU.%;e7 surgery. The importance of age-related cataract surgery will
F}DD;K increase further with the ageing of the population: the
e>Y2q|S85 number of people over age 60 years is expected to double in
`R?W @,@' the next 20 years. Cataract surgery services are well
W
A}@n accessed by the Victorian population and the visual outcomes
zL}hFmh of cataract surgery have been shown to be very good.
EC&,0i4n: These data can be used to plan for age-related cataract
k4rBS surgical services in Australia in the future as the need for
0.0!5D[ cataract extractions increases.
BF!zfX?n ACKNOWLEDGEMENTS
Lc?O K"[m The Visual Impairment Project was funded in part by grants
e_-/p`9 from the Victorian Health Promotion Foundation, the
&2igX?60 National Health and Medical Research Council, the Ansell
n82Q.M-H Ophthalmology Foundation, the Dorothy Edols Estate and
sR.j~R the Jack Brockhoff Foundation. Dr McCarty is the recipient
#Q
7$I.O] of a Wagstaff Fellowship in Ophthalmology from the Royal
H-w|JH>g Victorian Eye and Ear Hospital.
18`%WUPnT REFERENCES
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