ABSTRACT
/5u<78GW1 Purpose: To quantify the prevalence of cataract, the outcomes
?#fu.YE\ of cataract surgery and the factors related to
2nR[Xh?L unoperated cataract in Australia.
2
AMo:Jqv Methods: Participants were recruited from the Visual
=
>_\fNy Impairment Project: a cluster, stratified sample of more than
#3gp6*R 5000 Victorians aged 40 years and over. At examination
[Al& sites interviews, clinical examinations and lens photography
k7T`bYv were performed. Cataract was defined in participants who
y !_C/!d had: had previous cataract surgery, cortical cataract greater
sVOyT*GY than 4/16, nuclear greater than Wilmer standard 2, or
R=QZgpR posterior subcapsular greater than 1 mm2.
c9&xe"v Results: The participant group comprised 3271 Melbourne
]?!mS[X residents, 403 Melbourne nursing home residents and 1473
TA4!$7b$ rural residents.The weighted rate of any cataract in Victoria
~5}*
d was 21.5%. The overall weighted rate of prior cataract
L6|oyf surgery was 3.79%. Two hundred and forty-nine eyes had
,,q10iF had prior cataract surgery. Of these 249 procedures, 49
~kEI4}O (20%) were aphakic, 6 (2.4%) had anterior chamber
y.< m#Zzt intraocular lenses and 194 (78%) had posterior chamber
RO'7\xvn intraocular lenses.Two hundred and eleven of these operated
V<T9&8l+: eyes (85%) had best-corrected visual acuity of 6/12 or
!
t?iXZ
better, the legal requirement for a driver’s license.Twentyseven
8|l\EVV6 (11%) had visual acuity of less than 6/18 (moderate
JehrDC2N vision impairment). Complications of cataract surgery
$#9;)8J caused reduced vision in four of the 27 eyes (15%), or 1.9%
GLeK'0Q@ of operated eyes. Three of these four eyes had undergone
{#
?N intracapsular cataract extraction and the fourth eye had an
LnH ?dy opaque posterior capsule. No one had bilateral vision
C26>BU< impairment as a result of cataract surgery. Surprisingly, no
&m)6J'q3k particular demographic factors (such as age, gender, rural
,9zjFI residence, occupation, employment status, health insurance
i:Y^{\Z?V status, ethnicity) were related to the presence of unoperated
QI'Oz{vE cataract.
[+n*~ Conclusions: Although the overall prevalence of cataract is
aBNc(?ri quite high, no particular subgroup is systematically underserviced
Q ayPo]O in terms of cataract surgery. Overall, the results of
_E@2ZnD2 cataract surgery are very good, with the majority of eyes
C
zs8!S achieving driving vision following cataract extraction.
Yg%I? Key words: cataract extraction, health planning, health
r*2+xDoEi services accessibility, prevalence
x[~b2o INTRODUCTION
saBVgSd Cataract is the leading cause of blindness worldwide and, in
4i)1'{e Australia, cataract extractions account for the majority of all
C~,a!
qY ophthalmic procedures.1 Over the period 1985–94, the rate
y" RF;KW> of cataract surgery in Australia was twice as high as would be
zy/
@
WFPE expected from the growth in the elderly population.1
i[7\[ Although there have been a number of studies reporting
le|~BG hL the prevalence of cataract in various populations,2–6 there is
o=1Uh,S3R little information about determinants of cataract surgery in
4gI/!,J(b the population. A previous survey of Australian ophthalmologists
e$<0
7Oc showed that patient concern and lifestyle, rather
%9KldcQ}~ than visual acuity itself, are the primary factors for referral
Ns
>-
o for cataract surgery.7 This supports prior research which has
D=j-!{zB shown that visual acuity is not a strong predictor of need for
S 6@u@C cataract surgery.8,9 Elsewhere, socioeconomic status has
i1ixi\P{0 been shown to be related to cataract surgery rates.10
'N (:@]4N To appropriately plan health care services, information is
4[m`# needed about the prevalence of age-related cataract in the
Y2N>HK0 community as well as the factors associated with cataract
I667Gz$j5 surgery. The purpose of this study is to quantify the prevalence
T"{>t of any cataract in Australia, to describe the factors
Yg]-wQrH related to unoperated cataract in the community and to
ky
R:[+je describe the visual outcomes of cataract surgery.
g1/:Q%R,
METHODS
>c1q
pk/ Study population
[_R~%Yh+'E Details about the study methodology for the Visual
%<\vGqsM Impairment Project have been published previously.11
8g@<d^8@ Briefly, cluster sampling within three strata was employed to
b z`+ k,* recruit subjects aged 40 years and over to participate.
dU&a{$ku[ Within the Melbourne Statistical Division, nine pairs of
[owWiN4`s census collector districts were randomly selected. Fourteen
py$Q nursing homes within a 5 km radius of these nine test sites
pNG:0 were randomly chosen to recruit nursing home residents.
'F+C4QAq Clinical and Experimental Ophthalmology (2000) 28, 77–82
Go5J%&E9 Original Article
;v}GJ<3 Operated and unoperated cataract in Australia
Q:2>}QgX} Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
|XaIx#n Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
v> LIvi|] n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
= 6j&4p
` Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au nD_GL 78 McCarty et al.
HZ aV7dOZ8 Finally, four pairs of census collector districts in four rural
$njUXSQ; Victorian communities were randomly selected to recruit rural
\T4v|P
w\ residents. A household census was conducted to identify
A!od9W6 eligible residents aged 40 years and over who had been a
/Wi[OT14 resident at that address for at least 6 months. At the time of
:tz#v`3o the household census, basic information about age, sex,
:NhO2L country of birth, language spoken at home, education, use of
7o7)0l9! corrective spectacles and use of eye care services was collected.
!S$:*5=& Eligible residents were then invited to attend a local
fe\mL mK9 examination site for a more detailed interview and examination.
|)IlMG The study protocol was approved by the Royal Victorian
M92dZ1+6 Eye and Ear Hospital Human Research Ethics Committee.
rlML W Assessment of cataract
qLO4#CKCL6 A standardized ophthalmic examination was performed after
:N:yLd} & pupil dilatation with one drop of 10% phenylephrine
pd:WEI
, hydrochloride. Lens opacities were graded clinically at the
RFi
S@.7 time of the examination and subsequently from photos using
xipU8'ac/ the Wilmer cataract photo-grading system.12 Cortical and
&y
ct!YOB2 posterior subcapsular (PSC) opacities were assessed on
kDEX
N retroillumination and measured as the proportion (in 1/16)
x!?u^ of pupil circumference occupied by opacity. For this analysis,
IQAZuN"< cortical cataract was defined as 4/16 or greater opacity,
q}b
dxa PSC cataract was defined as opacity equal to or greater than
8Q.T g. 1 mm2 and nuclear cataract was defined as opacity equal to
;(b9#b. or greater than Wilmer standard 2,12 independent of visual
^a/gBC82x acuity. Examples of the minimum opacities defined as cortical,
6,^>mNm nuclear and PSC cataract are presented in Figure 1.
%2}-2}[> Bilateral congenital cataracts or cataracts secondary to
6`&a&%,O intraocular inflammation or trauma were excluded from the
;"xfOzQ analysis. Two cases of bilateral secondary cataract and eight
~G)S
cases of bilateral congenital cataract were excluded from the
;d@#XIS&-( analyses.
U2ohHJ`` A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
T"(&b~m2b4 Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
dhC$W!N7! height set to an incident angle of 30° was used for examinations.
>>QY'1Eu Ektachrome® 200 ASA colour slide film (Eastman
mbKZJ{|4s Kodak Company, Rochester, NY, USA) was used to photograph
0B[="rTS7# the nuclear opacities. The cortical opacities were
bYc
V$KJk photographed with an Oxford® retroillumination camera
;
8_{e3s (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
'I`&Yo~c9 film (Eastman Kodak). Photographs were graded separately
R
&n
Pj~ by two research assistants and discrepancies were adjudicated
|{&{ by an independent reviewer. Any discrepancies
,xw#NG6 between the clinical grades and the photograph grades were
~b(i&DVK resolved. Except in cases where photographs were missing,
bc*X/). the photograph grades were used in the analyses. Photograph
vXev$x=w- grades were available for 4301 (84%) for cortical
FX;QG94! cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
goLL;AL for PSC cataract. Cataract status was classified according to
]q\b,)4
e the severity of the opacity in the worse eye.
c|f<u
{' Assessment of risk factors
*tGY6=7O A standardized questionnaire was used to obtain information
l(yZO$ about education, employment and ethnic background.11
QfmJn(( Specific information was elicited on the occurrence, duration
S};#+ufgTt and treatment of a number of medical conditions,
.[YuRLGz including ocular trauma, arthritis, diabetes, gout, hypertension
Plc-4y1 and mental illness. Information about the use, dose and
&g#@3e1> duration of tobacco, alcohol, analgesics and steriods were
sm9k/(- collected, and a food frequency questionnaire was used to
%J#YM'g determine current consumption of dietary sources of antioxidants
pD(j'[ and use of vitamin supplements.
5b5x!do Data management and statistical analysis
+u.1 ;qF Data were collected either by direct computer entry with a
SfA\}@3 questionnaire programmed in Paradox© (Carel Corporation,
65L6:}# Ottawa, Canada) with internal consistency checks, or
{M3qLf~z#C on self-coding forms. Open-ended responses were coded at
{vs
uPY
a later time. Data that were entered on the self-coded forms
lVd^
^T*fh were entered into a computer with double data entry and
57aXQ8u{ reconciliation of any inconsistencies. Data range and consistency
~W*FCG#
E checks were performed on the entire data set.
"7U4'Y:E SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
[<7@{
;r employed for statistical analyses.
^9m\=5d Ninety-five per cent confidence limits around the agespecific
C,wL0Yj[ rates were calculated according to Cochran13 to
>
f^r^P account for the effect of the cluster sampling. Ninety-five
H[m:0
eF'5 per cent confidence limits around age-standardized rates
Gq+z /Be were calculated according to Breslow and Day.14 The strataspecific
!]42^?GH data were weighted according to the 1996
@>u}eB>Kn Australian Bureau of Statistics census data15 to reflect the
I?]ohG K cataract prevalence in the entire Victorian population.
Wf
u(* Univariate analyses with Student’s t-tests and chi-squared
~Uu
4= tests were first employed to evaluate risk factors for unoperated
iM AfJ-oN cataract. Any factors with P < 0.10 were then fitted
-O1>|y2rU into a backwards stepwise logistic regression model. For the
=FlDb
5t{ Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
C](f>)Dz
/ final multivariate models, P < 0.05 was considered statistically
6RG)`bu significant. Design effect was assessed through the use
>l]Xz*HE of cluster-specific models and multivariate models. The
>/g#lS 5 design effect was assumed to be additive and an adjustment
:C7_Jp*Qv made in the variance by adding the variance associated with
d<% z
1Dj2 the design effect prior to constructing the 95% confidence
"76]u) limits.
>d*iD RESULTS
?iPC* Study population
//*
fSF A total of 3271 (83%) of the Melbourne residents, 403
!_"@^?,q (90%) Melbourne nursing home residents, and 1473 (92%)
2I%MAb&1@ rural residents participated. In general, non-participants did
%.vQU @2A not differ from participants.16 The study population was
u&1q [0y representative of the Victorian population and Australia as
+vvv[ a whole.
MPCBT!o
4Z The Melbourne residents ranged in age from 40 to
U [*FCD!~ 98 years (mean = 59) and 1511 (46%) were male. The
e63uLWDT Melbourne nursing home residents ranged in age from 46 to
wL;lQ& 101 years (mean = 82) and 85 (21%) were men. The rural
)n+Lo&C< residents ranged in age from 40 to 103 years (mean = 60)
s2teym,uG and 701 (47.5%) were men.
hq%?=2'9? Prevalence of cataract and prior cataract surgery
ks"|}9\%< As would be expected, the rate of any cataract increases
E;,u2[3 dramatically with age (Table 1). The weighted rate of any
.}&`TU cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
Z?}dq-
Vh& Although the rates varied somewhat between the three
&wie] strata, they were not significantly different as the 95% confidence
<nE>XAI_7 limits overlapped. The per cent of cataractous eyes
BZ:H`M`n with best-corrected visual acuity of less than 6/12 was 12.5%
t=|evOz] (65/520) for cortical cataract, 18% for nuclear cataract
oT^{b\XN (97/534) and 14.4% (27/187) for PSC cataract. Cataract
./,/y"x surgery also rose dramatically with age. The overall
t5[#x4
p weighted rate of prior cataract surgery in Victoria was
GO8GJ;B-U 3.79% (95% CL 2.97, 4.60) (Table 2).
, 0imiv Risk factors for unoperated cataract
os,* 3WO Cases of cataract that had not been removed were classified
y603$Cv as unoperated cataract. Risk factor analyses for unoperated
4^TG>j?M cataract were not performed with the nursing home residents
a
AJU`=uq as information about risk factor exposure was not
aI
Jt0; available for this cohort. The following factors were assessed
%JXE5l+pJ in relation to unoperated cataract: age, sex, residence
6`O.!|) (urban/rural), language spoken at home (a measure of ethnic
L0*nm.1X integration), country of birth, parents’ country of birth (a
lV`Q{bd+ measure of ethnicity), years since migration, education, use
F5?m6`g? of ophthalmic services, use of optometric services, private
cVubb}ou health insurance status, duration of distance glasses use,
|rJ=Ksc glaucoma, age-related maculopathy and employment status.
uZc`jNc\ In this cross sectional study it was not possible to assess the
#z&&M"*a| level of visual acuity that would predict a patient’s having
uv=.2U46 cataract surgery, as visual acuity data prior to cataract
`dFq:8v surgery were not available.
&S( .GdEf The significant risk factors for unoperated cataract in univariate
>SML"+> analyses were related to: whether a participant had
=4[v3Qx ever seen an optometrist, seen an ophthalmologist or been
M:-.o diagnosed with glaucoma; and participants’ employment
3 DD ML, status (currently employed) and age. These significant
"B= factors were placed in a backwards stepwise logistic regression
b?TO=~k, model. The factors that remained significantly related
2@9Tfm(= to unoperated cataract were whether participants had ever
]vgB4~4#LP seen an ophthalmologist, seen an optometrist and been
Jd%H2` diagnosed with glaucoma. None of the demographic factors
f
#?fxUH~ were associated with unoperated cataract in the multivariate
&0
NFb^8+ model.
O$IEn/%+ The per cent of participants with unoperated cataract
cc#gEm)3C who said that they were dissatisfied or very dissatisfied with
U 'R)x";= Operated and unoperated cataract in Australia 79
6b+b/>G0 Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
OJ/,pLYu Age group Sex Urban Rural Nursing home Weighted total
)#.<]&P } (years) (%) (%) (%)
X=hYB}}nu 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
9:,V
5n
= Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
hJDi7P 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
>iD )eB Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
sA'6ty 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
;k7
xMZs Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
XLAN Np%E 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
s0DGC
Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
BB~OqZIP 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
UG)8D5 Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
LXEfPLS 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
mH Ic f{RG Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
b!sRk@LGZ Age-standardized
4F
{)i (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)
l~6?kFy9h aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
E_8\f_%wK their current vision was 30% (290/683), compared with 27%
1
E73i_L (26/95) of participants with prior cataract surgery (chisquared,
/C>wd 1 d.f. = 0.25, P = 0.62).
MxY/`9>E|+ Outcomes of cataract surgery
rb1`UG"h$ Two hundred and forty-nine eyes had undergone prior
ai
nG6Y<O` cataract surgery. Of these 249 operated eyes, 49 (20%) were
Hm$=h>rY9[ left aphakic, 6 (2.4%) had anterior chamber intraocular
-C<zF`jO lenses and 194 (78%) had posterior chamber intraocular
<^zHE=h" lenses. The rate of capsulotomy in the eyes with intact
>B2:kY F posterior capsules was 36% (73/202). Fifteen per cent of
[P 06lIO eyes (17/114) with a clear posterior capsule had bestcorrected
2 !At2P2 visual acuity of less than 6/12 compared with 43%
|!"2fI of eyes (6/14) with opaque capsules, and 15% of eyes
?r?jl;A& (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
-5T=:2M P = 0.027).
7.Z@Wr? The percentage of eyes with best-corrected visual acuity
^my].Qpt of 6/12 or better was 96% (302/314) for eyes without
,4ei2`wV cataract, 88% (1417/1609) for eyes with prevalent cataract
4dhvFGlW and 85% (211/249) for eyes with operated cataract (chisquared,
*,Za6.= 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
e _/b2"{ operated eyes (11%) had visual acuities of less than 6/18
f-5:wM& (moderate vision impairment) (Fig. 2). A cause of this
z}{afEb moderate visual impairment (but not the only cause) in four
e_V O3" (15%) eyes was secondary to cataract surgery. Three of these
RB+N
IoQQ| four eyes had undergone intracapsular cataract extraction
|i ZfYi&^ and the fourth eye had an opaque posterior capsule. No one
7c~u=U" had bilateral vision impairment as a result of their cataract
~i21%$ surgery.
$
6CwkM: DISCUSSION
-.T&(&>^ To our knowledge, this is the first paper to systematically
j%y$_9a7 assess the prevalence of current cataract, previous cataract
HO[wTB|D] surgery, predictors of unoperated cataract and the outcomes
1P(|[W1 of cataract surgery in a population-based sample. The Visual
wbe<'/X+ Impairment Project is unique in that the sampling frame and
F35#dIs`& high response rate have ensured that the study population is
ZeEWp3vW representative of Australians aged 40 years and over. Therefore,
D`xHD#j h these data can be used to plan age-related cataract
]ix!tb.Q services throughout Australia.
<D::9c j We found the rate of any cataract in those over the age
;s~X of 40 years to be 22%. Although relatively high, this rate is
O)Y?=G)
significantly less than was reported in a number of previous
;L,mBQB?0b studies,2,4,6 with the exception of the Casteldaccia Eye
]>+PnP35G Study.5 However, it is difficult to compare rates of cataract
OQ,NOiNkap between studies because of different methodologies and
eYC ^4g%l( cataract definitions employed in the various studies, as well
l/Vo-# as the different age structures of the study populations.
+n7?S~R$ Other studies have used less conservative definitions of
E"L2&. cataract, thus leading to higher rates of cataract as defined.
8HZs>l In most large epidemiologic studies of cataract, visual acuity
fPR$kch
has not been included in the definition of cataract.
sg8/#_S1i Therefore, the prevalence of cataract may not reflect the
_ z;q9&J) actual need for cataract surgery in the community.
+z9gbcx 80 McCarty et al.
_$p$") Table 2. Prevalence of previous cataract by age, gender and cohort
4]/7 )x?R Age group Gender Urban Rural Nursing home Weighted total
t!2(7=P30( (years) (%) (%) (%)
4pln5v= 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
@G:V Female 0.00 0.00 0.00 0.00 (
w ~ dk#= 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
Z lHDi!T Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
n 3lE,b 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
zS
E<"(
a Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
@m?QR(LJ 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
!J=sk4T Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
cv(PP-'\ 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
*FfMI Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
(Z}>1WRju 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
s!9dQ. Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
CdUAy|!`R Age-standardized
n$aA)"A # (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)
f""`cdqAOh Figure 2. Visual acuity in eyes that had undergone cataract
^ZM0c>ev=l surgery, n = 249. h, Presenting; j, best-corrected.
Fxc)}i`
Operated and unoperated cataract in Australia 81
X1tXqHJF} The weighted prevalence of prior cataract surgery in the
9]'($:LF08 Visual Impairment Project (3.6%) was similar to the crude
zKFp5H1!%+ rate in the Beaver Dam Eye Study4 (3.1%), but less than the
,&Wn [G<2 crude rate in the Blue Mountains Eye Study6 (6.0%).
81%8{yn!$" However, the age-standardized rate in the Blue Mountains
WS2osBc Eye Study (standardized to the age distribution of the urban
>O/D!j| Visual Impairment Project cohort) was found to be less than
z
NSu the Visual Impairment Project (standardized rate = 1.36%,
^O^:$nXhYy 95% CL 1.25, 1.47). The incidence of cataract surgery in
INSkgOo Australia has exceeded population growth.1 This is due,
qW_u perhaps, to advances in surgical techniques and lens
k#}g,0@ implants that have changed the risk–benefit ratio.
@^ ik[9^H The Global Initiative for the Elimination of Avoidable
~^)^q
8 Blindness, sponsored by the World Health Organization,
jy2IZ o states that cataract surgical services should be provided that
/q\_&@ ‘have a high success rate in terms of visual outcome and
Xj+q~4{|vt improved quality of life’,17 although the ‘high success rate’ is
:`vP}I ^ not defined. Population- and clinic-based studies conducted
s,*c@1f? in the United States have demonstrated marked improvement
s|bM%!$1 in visual acuity following cataract surgery.18–20 We
,}D}oo* found that 85% of eyes that had undergone cataract extraction
]7AX%EG3 had visual acuity of 6/12 or better. Previously, we have
7@%'wy&A shown that participants with prevalent cataract in this
^]p cohort are more likely to express dissatisfaction with their
%
qsvtc` current vision than participants without cataract or participants
S\NL+V?7h with prior cataract surgery.21 In a national study in the
VY 1vXM3y United States, researchers found that the change in patients’
;/AG@$) ratings of their vision difficulties and satisfaction with their
J?:[$ C5 vision after cataract surgery were more highly related to
t@bt6J .{ their change in visual functioning score than to their change
|I[7,`C~ in visual acuity.19 Furthermore, improvement in visual function
?Ce#BwQ> has been shown to be associated with improvement in
X}4}& overall quality of life.22
1@sM1WMX A recent review found that the incidence of visually
r@)A
k significant posterior capsule opacification following
j,%EW+j$ cataract surgery to be greater than 25%.23 We found 36%
|@VF.)_ capsulotomy in our population and that this was associated
\94j rr with visual acuity similar to that of eyes with a clear
,WTTJN capsule, but significantly better than that of eyes with an
[!*xO?yCJ opaque capsule.
X}JWf<=q A number of studies have shown that the demand and
}N3`gCy9eN timing of cataract surgery vary according to visual acuity,
]
VG?+ degree of handicap and socioeconomic factors.8–10,24,25 We
A]y*so!)> have also shown previously that ophthalmologists are more
z&'f/w8 likely to refer a patient for cataract surgery if the patient is
Z$2L~j"=! employed and less likely to refer a nursing home resident.7
3
XVk#)lw In the Visual Impairment Project, we did not find that any
@!H
'+c particular subgroup of the population was at greater risk of
Jh2Wr!5 having unoperated cataract. Universal access to health care
?eWJa in Australia may explain the fact that people without
@W9H9PWv& Medicare are more likely to delay cataract operations in the
a&5g!;. USA,8 but not having private health insurance is not associated
h(:<(o@< with unoperated cataract in Australia.
zO2{.4 In summary, cataract is a significant public health problem
I6w/0,azC in that one in four people in their 80s will have had cataract
dq8+m(7k surgery. The importance of age-related cataract surgery will
~zMKVM1Q., increase further with the ageing of the population: the
O)5#Fcp( number of people over age 60 years is expected to double in
'O "kt T the next 20 years. Cataract surgery services are well
{})y^L accessed by the Victorian population and the visual outcomes
u9>6|w+ of cataract surgery have been shown to be very good.
1o#vhk/"+ These data can be used to plan for age-related cataract
[:pl-_.C surgical services in Australia in the future as the need for
A}4t9|/K6 cataract extractions increases.
3/tJDb5 ACKNOWLEDGEMENTS
!fZLQc The Visual Impairment Project was funded in part by grants
0WS|~?OR@ from the Victorian Health Promotion Foundation, the
uHrb:X!q National Health and Medical Research Council, the Ansell
9Z9l:}bO Ophthalmology Foundation, the Dorothy Edols Estate and
_S<?t9mS the Jack Brockhoff Foundation. Dr McCarty is the recipient
\*9Ua/H of a Wagstaff Fellowship in Ophthalmology from the Royal
.nPL2zO Victorian Eye and Ear Hospital.
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