ABSTRACT
.3SP#mI Purpose: To quantify the prevalence of cataract, the outcomes
mZ0_^ of cataract surgery and the factors related to
,,g: x unoperated cataract in Australia.
)Ofwfypc Methods: Participants were recruited from the Visual
1M?S
l?+j Impairment Project: a cluster, stratified sample of more than
j*
~z.Q | 5000 Victorians aged 40 years and over. At examination
l=a<=i sites interviews, clinical examinations and lens photography
)
/z+W[t were performed. Cataract was defined in participants who
>keYx<1 had: had previous cataract surgery, cortical cataract greater
6kONuG7Yv than 4/16, nuclear greater than Wilmer standard 2, or
++!0r['+> posterior subcapsular greater than 1 mm2.
PpSQf14, Results: The participant group comprised 3271 Melbourne
mAe)Hy % residents, 403 Melbourne nursing home residents and 1473
}!WuJz" rural residents.The weighted rate of any cataract in Victoria
;9)=~) was 21.5%. The overall weighted rate of prior cataract
!$Arc^7r surgery was 3.79%. Two hundred and forty-nine eyes had
Xa$tW%) had prior cataract surgery. Of these 249 procedures, 49
("=B,%F_ (20%) were aphakic, 6 (2.4%) had anterior chamber
aOEW$% intraocular lenses and 194 (78%) had posterior chamber
Q:]v4/MT intraocular lenses.Two hundred and eleven of these operated
ciN*gwI) eyes (85%) had best-corrected visual acuity of 6/12 or
iP?lP= M better, the legal requirement for a driver’s license.Twentyseven
)<T2J0* (11%) had visual acuity of less than 6/18 (moderate
!!])~+4pP vision impairment). Complications of cataract surgery
LOk J caused reduced vision in four of the 27 eyes (15%), or 1.9%
:ZXaJ! of operated eyes. Three of these four eyes had undergone
?u{D-by%& intracapsular cataract extraction and the fourth eye had an
raZ0B,;eFu opaque posterior capsule. No one had bilateral vision
9n3. Ar impairment as a result of cataract surgery. Surprisingly, no
sv#/ 78 ~| particular demographic factors (such as age, gender, rural
KwxJ{$|xH residence, occupation, employment status, health insurance
a*o k*r status, ethnicity) were related to the presence of unoperated
B,A\/%< cataract.
(U*Zz+ R Conclusions: Although the overall prevalence of cataract is
1tH#QZIT quite high, no particular subgroup is systematically underserviced
-n6T^vf in terms of cataract surgery. Overall, the results of
?xo<Fv cataract surgery are very good, with the majority of eyes
?MJ5GVeH achieving driving vision following cataract extraction.
L$; gf_L Key words: cataract extraction, health planning, health
<}AmzeHr+ services accessibility, prevalence
62>/0_m5 INTRODUCTION
KI5099 _/ Cataract is the leading cause of blindness worldwide and, in
1i$OcN?x% Australia, cataract extractions account for the majority of all
)h;zH,DA[3 ophthalmic procedures.1 Over the period 1985–94, the rate
d6"B_,*b of cataract surgery in Australia was twice as high as would be
=L}$#Y8? expected from the growth in the elderly population.1
su Z` Although there have been a number of studies reporting
,CnUQx0 the prevalence of cataract in various populations,2–6 there is
W7
9.,# little information about determinants of cataract surgery in
jp-]];:aPJ the population. A previous survey of Australian ophthalmologists
%(kf#[zQ showed that patient concern and lifestyle, rather
+,bgOq\aG than visual acuity itself, are the primary factors for referral
:,=Z)e for cataract surgery.7 This supports prior research which has
pPZ^T5-ks shown that visual acuity is not a strong predictor of need for
w7h=vy n? cataract surgery.8,9 Elsewhere, socioeconomic status has
wGA%h.[M| been shown to be related to cataract surgery rates.10
pXHeUBY. To appropriately plan health care services, information is
F84?Mi{r2 needed about the prevalence of age-related cataract in the
zGE{Z A community as well as the factors associated with cataract
dLTA21b# surgery. The purpose of this study is to quantify the prevalence
CI,xp
of any cataract in Australia, to describe the factors
=;HmU.Uek% related to unoperated cataract in the community and to
;V3d"@R, describe the visual outcomes of cataract surgery.
;= {Z Bx METHODS
nzORG Study population
MEn#MT/Cz Details about the study methodology for the Visual
JSm3ZP|GqJ Impairment Project have been published previously.11
]6 {\`a Briefly, cluster sampling within three strata was employed to
MOW {g\{
\ recruit subjects aged 40 years and over to participate.
\:wLUGFl5 Within the Melbourne Statistical Division, nine pairs of
'$n#~/#} census collector districts were randomly selected. Fourteen
>ak53Ij$ nursing homes within a 5 km radius of these nine test sites
1"CbuV
6 were randomly chosen to recruit nursing home residents.
&c!=< <5M Clinical and Experimental Ophthalmology (2000) 28, 77–82
6Pa
jBEF Original Article
%C[ ;& Operated and unoperated cataract in Australia
]jzINaMav Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
c!%:f^7
g Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
<!vAqqljt n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
rXz,<^Hmj Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au ? I}T[j 78 McCarty et al.
.W&rcqy Finally, four pairs of census collector districts in four rural
-~h2^Oez Victorian communities were randomly selected to recruit rural
"t"=9:_t residents. A household census was conducted to identify
mlgdw
M eligible residents aged 40 years and over who had been a
.-N9\GlJ,d resident at that address for at least 6 months. At the time of
"FaG5X( the household census, basic information about age, sex,
f|FQd3o) country of birth, language spoken at home, education, use of
}~-)31e'` corrective spectacles and use of eye care services was collected.
=k`(!r2"# Eligible residents were then invited to attend a local
M42D5|tZc examination site for a more detailed interview and examination.
$zz=>BOk The study protocol was approved by the Royal Victorian
mcDW&jwQ Eye and Ear Hospital Human Research Ethics Committee.
6M$.gX
G. Assessment of cataract
^ I,1kl~i A standardized ophthalmic examination was performed after
n]coqJ pupil dilatation with one drop of 10% phenylephrine
8N-~ .p hydrochloride. Lens opacities were graded clinically at the
h/(9AO}t time of the examination and subsequently from photos using
5'V'~Q% the Wilmer cataract photo-grading system.12 Cortical and
T*h+"TmE posterior subcapsular (PSC) opacities were assessed on
p7H*Ff` retroillumination and measured as the proportion (in 1/16)
!b _<_Y{l of pupil circumference occupied by opacity. For this analysis,
3+ i(fg_ cortical cataract was defined as 4/16 or greater opacity,
o~>p=5t PSC cataract was defined as opacity equal to or greater than
5-mJj&0:! 1 mm2 and nuclear cataract was defined as opacity equal to
l]v
*h0! or greater than Wilmer standard 2,12 independent of visual
`(o1&
acuity. Examples of the minimum opacities defined as cortical,
U;V. +onv nuclear and PSC cataract are presented in Figure 1.
zLh ~x Bilateral congenital cataracts or cataracts secondary to
^*{xTB57 intraocular inflammation or trauma were excluded from the
acGmRP9g analysis. Two cases of bilateral secondary cataract and eight
m/ 6oQ cases of bilateral congenital cataract were excluded from the
([9h.M6v analyses.
hU=J^Gi0 A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
ap6Vmp Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
m1[QD26 height set to an incident angle of 30° was used for examinations.
%ri4nKGS Ektachrome® 200 ASA colour slide film (Eastman
zA"D0fr Kodak Company, Rochester, NY, USA) was used to photograph
I8Zp#'|U the nuclear opacities. The cortical opacities were
xY~
DMcO? photographed with an Oxford® retroillumination camera
5r+0^UAO:J (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
I Mv^ 9T: film (Eastman Kodak). Photographs were graded separately
[{ { ?e6J by two research assistants and discrepancies were adjudicated
,jt098W by an independent reviewer. Any discrepancies
Bs1-UI}+ between the clinical grades and the photograph grades were
Asn0&Ys4 resolved. Except in cases where photographs were missing,
vfbe=)}[ the photograph grades were used in the analyses. Photograph
| 5L1\O8# grades were available for 4301 (84%) for cortical
R_N<j cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
oOL3O@)w> for PSC cataract. Cataract status was classified according to
kCC9U_dj, the severity of the opacity in the worse eye.
8;!Eqyt Assessment of risk factors
{fb~`=? A standardized questionnaire was used to obtain information
=Hx~]1 about education, employment and ethnic background.11
dikWk Specific information was elicited on the occurrence, duration
.3U[@ *b( and treatment of a number of medical conditions,
<bx9;1C>zd including ocular trauma, arthritis, diabetes, gout, hypertension
@*uX[) and mental illness. Information about the use, dose and
>b["T+ duration of tobacco, alcohol, analgesics and steriods were
ommKf[h%i collected, and a food frequency questionnaire was used to
r~}}o o4K determine current consumption of dietary sources of antioxidants
IP'igX and use of vitamin supplements.
46zaxcY<! Data management and statistical analysis
#8z,'~\ Data were collected either by direct computer entry with a
:xw3b)KS questionnaire programmed in Paradox© (Carel Corporation,
AIm$in`P Ottawa, Canada) with internal consistency checks, or
nP3GI:mjL on self-coding forms. Open-ended responses were coded at
+^J-'7Vt a later time. Data that were entered on the self-coded forms
IPO[J^#Me were entered into a computer with double data entry and
GVEWd/:X( reconciliation of any inconsistencies. Data range and consistency
u3wC
}Zo checks were performed on the entire data set.
M?B(<j1Ri SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
pIu H*4Vz employed for statistical analyses.
X[E
k'=} Ninety-five per cent confidence limits around the agespecific
5(|M["KK~ rates were calculated according to Cochran13 to
4VNb`!e account for the effect of the cluster sampling. Ninety-five
:Nz?<3R0\ per cent confidence limits around age-standardized rates
<M,H9^l3 were calculated according to Breslow and Day.14 The strataspecific
nuQ6X5>.= data were weighted according to the 1996
}IN_5o(( Australian Bureau of Statistics census data15 to reflect the
c,q"}nE8w cataract prevalence in the entire Victorian population.
t;!]z-Y> Univariate analyses with Student’s t-tests and chi-squared
hRr1#'& tests were first employed to evaluate risk factors for unoperated
T;4`wB8@ cataract. Any factors with P < 0.10 were then fitted
v'Vt
.m&9& into a backwards stepwise logistic regression model. For the
9>Uq$B Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
`.'i V[fr final multivariate models, P < 0.05 was considered statistically
u5Ny=Xm significant. Design effect was assessed through the use
14D7U/zer of cluster-specific models and multivariate models. The
?Hi}nsw design effect was assumed to be additive and an adjustment
*sw-eyn( made in the variance by adding the variance associated with
N\q)LM !M the design effect prior to constructing the 95% confidence
`\jTpDV_W limits.
YN@6}B#1 RESULTS
VD24X Study population
}t|Plz A total of 3271 (83%) of the Melbourne residents, 403
>{m2E8U0 (90%) Melbourne nursing home residents, and 1473 (92%)
nG"n-$A?< rural residents participated. In general, non-participants did
qWO]s=V! not differ from participants.16 The study population was
1n'$Ji7 representative of the Victorian population and Australia as
&xiOTkqB a whole.
/2e%s:")h The Melbourne residents ranged in age from 40 to
*KK[(o}^J- 98 years (mean = 59) and 1511 (46%) were male. The
+2DE/wE]e+ Melbourne nursing home residents ranged in age from 46 to
CE#\Roi x) 101 years (mean = 82) and 85 (21%) were men. The rural
9g
Bjxqm residents ranged in age from 40 to 103 years (mean = 60)
5VR.o!h3I and 701 (47.5%) were men.
:N@U[Wx0A Prevalence of cataract and prior cataract surgery
x(PKFn As would be expected, the rate of any cataract increases
QCOLC2I dramatically with age (Table 1). The weighted rate of any
(kIz cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
hq<5lE^ Although the rates varied somewhat between the three
!4R>O6k strata, they were not significantly different as the 95% confidence
X JY5@I. limits overlapped. The per cent of cataractous eyes
'>3`rsu with best-corrected visual acuity of less than 6/12 was 12.5%
l'U1
01M>F (65/520) for cortical cataract, 18% for nuclear cataract
nr OqH
(97/534) and 14.4% (27/187) for PSC cataract. Cataract
4\M8BRuE surgery also rose dramatically with age. The overall
!?n
u? weighted rate of prior cataract surgery in Victoria was
%}C9 3.79% (95% CL 2.97, 4.60) (Table 2).
Xv0F:1 Risk factors for unoperated cataract
,"Tjpdf Cases of cataract that had not been removed were classified
'61i2\[lZQ as unoperated cataract. Risk factor analyses for unoperated
~r<p@k=.#0 cataract were not performed with the nursing home residents
t5paYw-b as information about risk factor exposure was not
:B
ZMnCfA available for this cohort. The following factors were assessed
2F1ZAl in relation to unoperated cataract: age, sex, residence
u_.HPA (urban/rural), language spoken at home (a measure of ethnic
f=o4I2Y[ integration), country of birth, parents’ country of birth (a
XLm@etf measure of ethnicity), years since migration, education, use
KmQ^?Ad-C of ophthalmic services, use of optometric services, private
:u
o[&&c health insurance status, duration of distance glasses use,
?;
[ T glaucoma, age-related maculopathy and employment status.
gg[9u- In this cross sectional study it was not possible to assess the
t?{B_Bf level of visual acuity that would predict a patient’s having
]#zZWg
zv cataract surgery, as visual acuity data prior to cataract
_A 2Lv]vfV surgery were not available.
W"Q!|#;l. The significant risk factors for unoperated cataract in univariate
2n|CD|V$ux analyses were related to: whether a participant had
:p>hW!~ ever seen an optometrist, seen an ophthalmologist or been
S`iR9{+& diagnosed with glaucoma; and participants’ employment
"MnSJ2 status (currently employed) and age. These significant
^ve14mbF#. factors were placed in a backwards stepwise logistic regression
VFj(M
j`}G model. The factors that remained significantly related
x<ax9{ to unoperated cataract were whether participants had ever
|~K(F<;j seen an ophthalmologist, seen an optometrist and been
6
|!NLwa diagnosed with glaucoma. None of the demographic factors
xWE8Wm were associated with unoperated cataract in the multivariate
rh%m;i<b model.
g97]Y1g
The per cent of participants with unoperated cataract
@{d\j]Nw who said that they were dissatisfied or very dissatisfied with
kl}Xmw{tJ Operated and unoperated cataract in Australia 79
R7?29?$7 Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
mfom=-q3k Age group Sex Urban Rural Nursing home Weighted total
oyx^a9 (years) (%) (%) (%)
}Ln@R~[ 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
{fDTSr?/ Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
!HK^AwNY 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
xT*d/Oa w Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
g(hOg~S\E 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
<
<Y}~N Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
{1-V]h.<J 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
6'C2SihYp Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
K#mOSY;} 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
-YGbfd<wq Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
1(#;&:$`i 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
?GT@puJS- Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
(Ddp|a"b Age-standardized
$_;e>*+x (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
1Sz
A3c aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
&^".2)zU their current vision was 30% (290/683), compared with 27%
!Ng=Yk>3 (26/95) of participants with prior cataract surgery (chisquared,
D=r)) 1 d.f. = 0.25, P = 0.62).
OE`X<h4r Outcomes of cataract surgery
#*%q'gyHT Two hundred and forty-nine eyes had undergone prior
kOL'|GgK cataract surgery. Of these 249 operated eyes, 49 (20%) were
Z|lU8`'5 left aphakic, 6 (2.4%) had anterior chamber intraocular
Me5{_n lenses and 194 (78%) had posterior chamber intraocular
iBg3mc@OO lenses. The rate of capsulotomy in the eyes with intact
|*5 =_vF posterior capsules was 36% (73/202). Fifteen per cent of
2x]>l?
5b eyes (17/114) with a clear posterior capsule had bestcorrected
(2ot5x}`j visual acuity of less than 6/12 compared with 43%
M~e0lg8 of eyes (6/14) with opaque capsules, and 15% of eyes
7cDU2l (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
f|7\DeY9U P = 0.027).
S[3iA~)Z- The percentage of eyes with best-corrected visual acuity
*iO u' of 6/12 or better was 96% (302/314) for eyes without
{
P%
9 cataract, 88% (1417/1609) for eyes with prevalent cataract
zG }? and 85% (211/249) for eyes with operated cataract (chisquared,
8`>h}Q$ 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
^|~mlY@w operated eyes (11%) had visual acuities of less than 6/18
5@IB39 (moderate vision impairment) (Fig. 2). A cause of this
GG064zPq7 moderate visual impairment (but not the only cause) in four
h`
U?1xS (15%) eyes was secondary to cataract surgery. Three of these
C
(n+SY^ four eyes had undergone intracapsular cataract extraction
EKEjv|_) and the fourth eye had an opaque posterior capsule. No one
$n^MD_1! had bilateral vision impairment as a result of their cataract
<9E0iz+j surgery.
Va,<3z%O< DISCUSSION
4(e59
ZgY To our knowledge, this is the first paper to systematically
)[H{yQ assess the prevalence of current cataract, previous cataract
#/"8F O%~p surgery, predictors of unoperated cataract and the outcomes
ZUz ^!d of cataract surgery in a population-based sample. The Visual
7{e{9QbJ4 Impairment Project is unique in that the sampling frame and
9I1tN high response rate have ensured that the study population is
[Vd[- representative of Australians aged 40 years and over. Therefore,
+4[^!q*
H these data can be used to plan age-related cataract
F:*W5xX services throughout Australia.
}I3gU We found the rate of any cataract in those over the age
{o5V7*P;_ of 40 years to be 22%. Although relatively high, this rate is
FX9F"42@ significantly less than was reported in a number of previous
o]nw0q?
studies,2,4,6 with the exception of the Casteldaccia Eye
S3L~~X/= Study.5 However, it is difficult to compare rates of cataract
0ye!R
between studies because of different methodologies and
[V4 {c@ cataract definitions employed in the various studies, as well
'n<iU st as the different age structures of the study populations.
&/Ro lIHF Other studies have used less conservative definitions of
2o>)7^9|#< cataract, thus leading to higher rates of cataract as defined.
WL` 9~S In most large epidemiologic studies of cataract, visual acuity
G^q3Z#P has not been included in the definition of cataract.
?"z]A7<Hj Therefore, the prevalence of cataract may not reflect the
"V&+7"
Q actual need for cataract surgery in the community.
LH:i| I 80 McCarty et al.
rDm
'Z>nTf Table 2. Prevalence of previous cataract by age, gender and cohort
iCHt1VV] Age group Gender Urban Rural Nursing home Weighted total
%,hV[[ @. (years) (%) (%) (%)
>vuY+o;B 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
^<LY4^ Female 0.00 0.00 0.00 0.00 (
6sa"O89 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
"B_K
XL Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
QdLYCR4f 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
}E`dZW*!! Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
z5W@`=D 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
?BhMjsy. Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
y>*xVK{D 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
W+*5"h Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
"bDs2E+W 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
!~Q2|r Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
Jk0r&t7 Age-standardized
6i0A9SN (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)
w,Ee>cV]a Figure 2. Visual acuity in eyes that had undergone cataract
^( Rvk surgery, n = 249. h, Presenting; j, best-corrected.
*Sh^J+j Operated and unoperated cataract in Australia 81
Jjl`_X$CB The weighted prevalence of prior cataract surgery in the
uIU5.\"s Visual Impairment Project (3.6%) was similar to the crude
%p
X6QRt? rate in the Beaver Dam Eye Study4 (3.1%), but less than the
t#!yrQ..'G crude rate in the Blue Mountains Eye Study6 (6.0%).
k? Xc However, the age-standardized rate in the Blue Mountains
^fz+41lE\ Eye Study (standardized to the age distribution of the urban
7)%+=@
Visual Impairment Project cohort) was found to be less than
hQNe;R5 the Visual Impairment Project (standardized rate = 1.36%,
;O<9|? 95% CL 1.25, 1.47). The incidence of cataract surgery in
tTU=
+*Io Australia has exceeded population growth.1 This is due,
Su 5>$ perhaps, to advances in surgical techniques and lens
9_sA&2P{uV implants that have changed the risk–benefit ratio.
moVbw`T The Global Initiative for the Elimination of Avoidable
;60.l! Blindness, sponsored by the World Health Organization,
={?vAb: states that cataract surgical services should be provided that
ud fe ‘have a high success rate in terms of visual outcome and
KN"S?i]X improved quality of life’,17 although the ‘high success rate’ is
X,8<oX1r not defined. Population- and clinic-based studies conducted
SR*wvQnOx in the United States have demonstrated marked improvement
8>/Q1(q0 in visual acuity following cataract surgery.18–20 We
n&MG7`]N found that 85% of eyes that had undergone cataract extraction
76.{0c had visual acuity of 6/12 or better. Previously, we have
wv^rS^~ shown that participants with prevalent cataract in this
jPnM
>= cohort are more likely to express dissatisfaction with their
NA,CZ current vision than participants without cataract or participants
{YUIMd!Y with prior cataract surgery.21 In a national study in the
XBQ\_2> United States, researchers found that the change in patients’
{G*A.$-d ratings of their vision difficulties and satisfaction with their
*)]"27^ vision after cataract surgery were more highly related to
P6,7]6bp their change in visual functioning score than to their change
[Pe#kzLX in visual acuity.19 Furthermore, improvement in visual function
kX:tc has been shown to be associated with improvement in
qz4^{ overall quality of life.22
%7`f{|. A recent review found that the incidence of visually
@5)
8L/[l significant posterior capsule opacification following
$N2SfyX7 cataract surgery to be greater than 25%.23 We found 36%
A~nf#(!^] capsulotomy in our population and that this was associated
~8|t*@D with visual acuity similar to that of eyes with a clear
AGA`fRVx capsule, but significantly better than that of eyes with an
>Q,zNs opaque capsule.
hgRVwX A number of studies have shown that the demand and
8
6QE/M timing of cataract surgery vary according to visual acuity,
6pE :A@ degree of handicap and socioeconomic factors.8–10,24,25 We
(wRBd have also shown previously that ophthalmologists are more
04!(okubyp likely to refer a patient for cataract surgery if the patient is
!0/z>#b employed and less likely to refer a nursing home resident.7
=R*Gk4<Y In the Visual Impairment Project, we did not find that any
2}}?'PwwT particular subgroup of the population was at greater risk of
3HyhEVR-#~ having unoperated cataract. Universal access to health care
P];JKE% in Australia may explain the fact that people without
C-P06Q] Medicare are more likely to delay cataract operations in the
NCA{H^CL
USA,8 but not having private health insurance is not associated
;)DzCc/ with unoperated cataract in Australia.
g(0;[#@ In summary, cataract is a significant public health problem
fm1X1T . in that one in four people in their 80s will have had cataract
*.y' (tj[ surgery. The importance of age-related cataract surgery will
yeD_j/ increase further with the ageing of the population: the
FYPz 4K number of people over age 60 years is expected to double in
|U[y_Y\a the next 20 years. Cataract surgery services are well
d+z[\i accessed by the Victorian population and the visual outcomes
=.m6FRsU of cataract surgery have been shown to be very good.
RagiV6c These data can be used to plan for age-related cataract
g"t^r3 surgical services in Australia in the future as the need for
m>Ux`Gp+ cataract extractions increases.
1czG55 | ACKNOWLEDGEMENTS
*)VAaGUX> The Visual Impairment Project was funded in part by grants
f==*"?6\ from the Victorian Health Promotion Foundation, the
:B#EqeI National Health and Medical Research Council, the Ansell
M|CrBJv+F Ophthalmology Foundation, the Dorothy Edols Estate and
iV)ac\ the Jack Brockhoff Foundation. Dr McCarty is the recipient
+B
B0wY of a Wagstaff Fellowship in Ophthalmology from the Royal
dt-K Victorian Eye and Ear Hospital.
H/i<_
L P REFERENCES
cb+y9wA 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
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