ABSTRACT
RKwuvVI Purpose: To quantify the prevalence of cataract, the outcomes
LqoH]AcN of cataract surgery and the factors related to
hpzDQ6-Y unoperated cataract in Australia.
(zIF2qY Methods: Participants were recruited from the Visual
t[X,m]SX Impairment Project: a cluster, stratified sample of more than
4|xQQv 5000 Victorians aged 40 years and over. At examination
\vp^[,SI sites interviews, clinical examinations and lens photography
|k=5`WG were performed. Cataract was defined in participants who
!-s 6B had: had previous cataract surgery, cortical cataract greater
<M M(Z than 4/16, nuclear greater than Wilmer standard 2, or
js)I%Z posterior subcapsular greater than 1 mm2.
trM)&aQto Results: The participant group comprised 3271 Melbourne
SOQR(UT residents, 403 Melbourne nursing home residents and 1473
Rmh u"N/q rural residents.The weighted rate of any cataract in Victoria
jQY
^[A was 21.5%. The overall weighted rate of prior cataract
f4&k48Ds surgery was 3.79%. Two hundred and forty-nine eyes had
P*9L3R*=N had prior cataract surgery. Of these 249 procedures, 49
KAm$^N5 (20%) were aphakic, 6 (2.4%) had anterior chamber
~ ]^<*R intraocular lenses and 194 (78%) had posterior chamber
:hUt7/3c intraocular lenses.Two hundred and eleven of these operated
l8By2{pN eyes (85%) had best-corrected visual acuity of 6/12 or
O%rt7qV"g2 better, the legal requirement for a driver’s license.Twentyseven
07A2@dx (11%) had visual acuity of less than 6/18 (moderate
bT c'E# vision impairment). Complications of cataract surgery
3R ZD=` caused reduced vision in four of the 27 eyes (15%), or 1.9%
02~GT_)$^ of operated eyes. Three of these four eyes had undergone
G
M>Ms!Y intracapsular cataract extraction and the fourth eye had an
HD9+4~8 opaque posterior capsule. No one had bilateral vision
h/\/dp/tt impairment as a result of cataract surgery. Surprisingly, no
2 [yfo8H particular demographic factors (such as age, gender, rural
i T&Y9 residence, occupation, employment status, health insurance
n]J;BW&Av status, ethnicity) were related to the presence of unoperated
YOY{f:ew cataract.
lr&O@
5"oy Conclusions: Although the overall prevalence of cataract is
@-5V~itW quite high, no particular subgroup is systematically underserviced
h|Udw3N1L in terms of cataract surgery. Overall, the results of
S`Wau/7t cataract surgery are very good, with the majority of eyes
ICXz(?a achieving driving vision following cataract extraction.
C9}m-N
Key words: cataract extraction, health planning, health
e8$OV4X services accessibility, prevalence
g)#.|d+ INTRODUCTION
?ZlN$h^ Cataract is the leading cause of blindness worldwide and, in
;+iw?" Australia, cataract extractions account for the majority of all
+5IC-=
ZB ophthalmic procedures.1 Over the period 1985–94, the rate
Zlf)
dDn of cataract surgery in Australia was twice as high as would be
Jb"0P`senY expected from the growth in the elderly population.1
xlU:&=| Although there have been a number of studies reporting
xyc`p[n& the prevalence of cataract in various populations,2–6 there is
@$%[D`Wa< little information about determinants of cataract surgery in
u&s>UkR the population. A previous survey of Australian ophthalmologists
XH{P@2~l showed that patient concern and lifestyle, rather
b<?A than visual acuity itself, are the primary factors for referral
lVc':,z for cataract surgery.7 This supports prior research which has
@8qo(7<~Q shown that visual acuity is not a strong predictor of need for
t+`>zux5(T cataract surgery.8,9 Elsewhere, socioeconomic status has
]^
"BLbDZ@ been shown to be related to cataract surgery rates.10
biw2f~V To appropriately plan health care services, information is
0-a[[hL? needed about the prevalence of age-related cataract in the
v a
j community as well as the factors associated with cataract
yM-3nwk surgery. The purpose of this study is to quantify the prevalence
*{e?%!Q of any cataract in Australia, to describe the factors
G0VbW-`O related to unoperated cataract in the community and to
M<"H1>q@ describe the visual outcomes of cataract surgery.
xfJ&11fG2 METHODS
]iL>Zxex Study population
4+j:]poYG{ Details about the study methodology for the Visual
=ijVT_|u0 Impairment Project have been published previously.11
o(_~
st< Briefly, cluster sampling within three strata was employed to
L-v-KO6 recruit subjects aged 40 years and over to participate.
K4>nBvZ?v Within the Melbourne Statistical Division, nine pairs of
o$FYCz n census collector districts were randomly selected. Fourteen
jWL;ElM' nursing homes within a 5 km radius of these nine test sites
>UUT9:,plA were randomly chosen to recruit nursing home residents.
Kc[Y .CH Clinical and Experimental Ophthalmology (2000) 28, 77–82
:P1/kYg Original Article
o}4J|@Hi|4 Operated and unoperated cataract in Australia
ttaYtV]] Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
,*Z:a4 Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
XdR^,;pWE n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
)5(Ko<" Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au a6v ls]? 78 McCarty et al.
HECZZnM Finally, four pairs of census collector districts in four rural
uI*2}Q Victorian communities were randomly selected to recruit rural
Q:4euhz* residents. A household census was conducted to identify
$sX X6K), eligible residents aged 40 years and over who had been a
`mfN3Q*[c resident at that address for at least 6 months. At the time of
d].(x)|st the household census, basic information about age, sex,
EN!Q]O| country of birth, language spoken at home, education, use of
STxreW1 corrective spectacles and use of eye care services was collected.
"7T9d) Eligible residents were then invited to attend a local
&oyj8 examination site for a more detailed interview and examination.
Pd[&&!+gV The study protocol was approved by the Royal Victorian
, Q5Z<\
Eye and Ear Hospital Human Research Ethics Committee.
X+*"FKm S. Assessment of cataract
Dm.tYG A standardized ophthalmic examination was performed after
z'FJx2 pupil dilatation with one drop of 10% phenylephrine
zU7/P|Dw+ hydrochloride. Lens opacities were graded clinically at the
z^q ~|7 time of the examination and subsequently from photos using
HP
/@ _qk the Wilmer cataract photo-grading system.12 Cortical and
#q5
L4uM9 posterior subcapsular (PSC) opacities were assessed on
0y"Ra%Y retroillumination and measured as the proportion (in 1/16)
%Z"I=;=nxI of pupil circumference occupied by opacity. For this analysis,
Yc*Ex-s cortical cataract was defined as 4/16 or greater opacity,
NzP5s&,C69 PSC cataract was defined as opacity equal to or greater than
y^SDt3Am 1 mm2 and nuclear cataract was defined as opacity equal to
#!WD1a?L or greater than Wilmer standard 2,12 independent of visual
-Xw i}/OX acuity. Examples of the minimum opacities defined as cortical,
>J \} &!8, nuclear and PSC cataract are presented in Figure 1.
9?
#pqw Bilateral congenital cataracts or cataracts secondary to
cS'|c06 intraocular inflammation or trauma were excluded from the
KH<f=?b analysis. Two cases of bilateral secondary cataract and eight
f0^DsP
cases of bilateral congenital cataract were excluded from the
f_&bwfbo
analyses.
k365.nc A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
z8ox#+l Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
?G#T6$E8 height set to an incident angle of 30° was used for examinations.
Dm"@59x Ektachrome® 200 ASA colour slide film (Eastman
Lb'HM-d Kodak Company, Rochester, NY, USA) was used to photograph
C>?`1d@ the nuclear opacities. The cortical opacities were
%Q}T9%Mtj photographed with an Oxford® retroillumination camera
Gj.u/l (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
8?L7h\)- film (Eastman Kodak). Photographs were graded separately
;n9r;$!f by two research assistants and discrepancies were adjudicated
-L&FguoVB by an independent reviewer. Any discrepancies
qw!_/Z3[ between the clinical grades and the photograph grades were
i_? S#L]h resolved. Except in cases where photographs were missing,
2VNMz[W' the photograph grades were used in the analyses. Photograph
M-Az2x;6 grades were available for 4301 (84%) for cortical
tr]=q9
cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
m#E%,
rT for PSC cataract. Cataract status was classified according to
(Ut)APM the severity of the opacity in the worse eye.
p~T)Af<(
Assessment of risk factors
USKa6<:{W A standardized questionnaire was used to obtain information
a!1\,. about education, employment and ethnic background.11
'$]u?m Specific information was elicited on the occurrence, duration
K%) K$/A and treatment of a number of medical conditions,
PXZZPW/ including ocular trauma, arthritis, diabetes, gout, hypertension
dv+)U9at and mental illness. Information about the use, dose and
Y5}<7s\UDO duration of tobacco, alcohol, analgesics and steriods were
7I/ collected, and a food frequency questionnaire was used to
3H0~?z_ determine current consumption of dietary sources of antioxidants
IH;+pN and use of vitamin supplements.
MCOz-8@|Y Data management and statistical analysis
&></l| hY Data were collected either by direct computer entry with a
Nw`}iR0i questionnaire programmed in Paradox© (Carel Corporation,
N 798(" Ottawa, Canada) with internal consistency checks, or
vHY."$|H on self-coding forms. Open-ended responses were coded at
lNcXBtwK@# a later time. Data that were entered on the self-coded forms
@$R[Js%MuO were entered into a computer with double data entry and
sv<U$M~)X reconciliation of any inconsistencies. Data range and consistency
Rc2| o.'y checks were performed on the entire data set.
DwXzmp[qWH SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
P
+U=/$o employed for statistical analyses.
0hTv0#j# Ninety-five per cent confidence limits around the agespecific
bgW=.s rates were calculated according to Cochran13 to
DP=4<ES%+ account for the effect of the cluster sampling. Ninety-five
7/.- dfEK per cent confidence limits around age-standardized rates
\de824 were calculated according to Breslow and Day.14 The strataspecific
zG_e= data were weighted according to the 1996
KmoPFlw Australian Bureau of Statistics census data15 to reflect the
t'@1FA!)
cataract prevalence in the entire Victorian population.
gkdd#Nrk Univariate analyses with Student’s t-tests and chi-squared
K252l,;| tests were first employed to evaluate risk factors for unoperated
B;A^5~b cataract. Any factors with P < 0.10 were then fitted
OO..
Y into a backwards stepwise logistic regression model. For the
(\
`knsE! Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
73?ZB+\)0A final multivariate models, P < 0.05 was considered statistically
FL5u68
significant. Design effect was assessed through the use
#/'5
N|? of cluster-specific models and multivariate models. The
Cj?X+#J/@d design effect was assumed to be additive and an adjustment
@`<v d@ made in the variance by adding the variance associated with
L^: +8g the design effect prior to constructing the 95% confidence
>Zk$q~'+ limits.
cT
abZc RESULTS
hETTD% Study population
K29]B~0%E A total of 3271 (83%) of the Melbourne residents, 403
yW.s?3X (90%) Melbourne nursing home residents, and 1473 (92%)
$\>GQ~k rural residents participated. In general, non-participants did
yyJ4r}TE not differ from participants.16 The study population was
N%{&%C 6{ representative of the Victorian population and Australia as
:_YpSw<Q a whole.
:UmY|=v?t The Melbourne residents ranged in age from 40 to
@)m H"u!(7 98 years (mean = 59) and 1511 (46%) were male. The
(9x8,f0z Melbourne nursing home residents ranged in age from 46 to
c
F_hU" 101 years (mean = 82) and 85 (21%) were men. The rural
V2kNJwwk residents ranged in age from 40 to 103 years (mean = 60)
gc@,lNmi and 701 (47.5%) were men.
?#^(QR|/ Prevalence of cataract and prior cataract surgery
4J*%$Vxv As would be expected, the rate of any cataract increases
s
}q6@I dramatically with age (Table 1). The weighted rate of any
Hs<vC
L \ cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
'M2Jw8i Although the rates varied somewhat between the three
Oa=0d;_ strata, they were not significantly different as the 95% confidence
eX$P k: limits overlapped. The per cent of cataractous eyes
g]O"l?xx1D with best-corrected visual acuity of less than 6/12 was 12.5%
rJK3;d? E (65/520) for cortical cataract, 18% for nuclear cataract
jJ86Ch (97/534) and 14.4% (27/187) for PSC cataract. Cataract
(</cu$w>H) surgery also rose dramatically with age. The overall
`V[{(&?,n weighted rate of prior cataract surgery in Victoria was
t5n$sF 3.79% (95% CL 2.97, 4.60) (Table 2).
G@b|{! Risk factors for unoperated cataract
'Uqz , Cases of cataract that had not been removed were classified
z>+@pj
as unoperated cataract. Risk factor analyses for unoperated
aB~?Y+m cataract were not performed with the nursing home residents
9r%O as information about risk factor exposure was not
-sl]
funRy available for this cohort. The following factors were assessed
=xFw4D9 in relation to unoperated cataract: age, sex, residence
`yJpDGh (urban/rural), language spoken at home (a measure of ethnic
<m"Zk k integration), country of birth, parents’ country of birth (a
?)k;.<6 measure of ethnicity), years since migration, education, use
k2muHKBlk of ophthalmic services, use of optometric services, private
H\AJLk2E health insurance status, duration of distance glasses use,
?"[b408- glaucoma, age-related maculopathy and employment status.
dX-Xzg In this cross sectional study it was not possible to assess the
%JmSCjt`G level of visual acuity that would predict a patient’s having
%{g<{\@4(; cataract surgery, as visual acuity data prior to cataract
77"'? surgery were not available.
{j.5!Nj]B The significant risk factors for unoperated cataract in univariate
LC)
-aw>- analyses were related to: whether a participant had
.4pWyqU)! ever seen an optometrist, seen an ophthalmologist or been
.zO/8y(@ diagnosed with glaucoma; and participants’ employment
DYkNP:+ status (currently employed) and age. These significant
0q(}n v factors were placed in a backwards stepwise logistic regression
XqMJe'%r model. The factors that remained significantly related
{b~l[ to unoperated cataract were whether participants had ever
#Q}`kFB` seen an ophthalmologist, seen an optometrist and been
.^0@^%Wi diagnosed with glaucoma. None of the demographic factors
{[QCuR were associated with unoperated cataract in the multivariate
&u0JzK model.
Z}6
The per cent of participants with unoperated cataract
Q[J% who said that they were dissatisfied or very dissatisfied with
5SKj% %B2, Operated and unoperated cataract in Australia 79
xG i,\K\: Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
+x$GwX Age group Sex Urban Rural Nursing home Weighted total
"HSAwe`5jU (years) (%) (%) (%)
eSNi6RvE 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
zX{K\yp Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
57*`y'CW 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
6? u9hi Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
-:]_DbF 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
V'y,{YpP Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
R:8\z0"L* 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
jt5en;AA[ Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
v;4l*)$) 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
H|&[,&M> Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
,x#5 .Koz 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
P5/\*~} Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
b`M 2VZu Age-standardized
^ 'W<| (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
eP6`"<UM aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
uR#aO'' their current vision was 30% (290/683), compared with 27%
^5n"L29V (26/95) of participants with prior cataract surgery (chisquared,
62{(i'K 1 d.f. = 0.25, P = 0.62).
=y)e&bj Outcomes of cataract surgery
+zMWIG Two hundred and forty-nine eyes had undergone prior
Kxs_R#k cataract surgery. Of these 249 operated eyes, 49 (20%) were
Qf0 ]7 left aphakic, 6 (2.4%) had anterior chamber intraocular
mOm_a9ML lenses and 194 (78%) had posterior chamber intraocular
M@\A_x(Mas lenses. The rate of capsulotomy in the eyes with intact
J${'?!N posterior capsules was 36% (73/202). Fifteen per cent of
BC|=-^( eyes (17/114) with a clear posterior capsule had bestcorrected
XNODDH visual acuity of less than 6/12 compared with 43%
k0[b4cr` of eyes (6/14) with opaque capsules, and 15% of eyes
$,Q0ay (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
@APv?>$) P = 0.027).
j
0^%
1
The percentage of eyes with best-corrected visual acuity
!$}:4}56F of 6/12 or better was 96% (302/314) for eyes without
2/[J<c\G cataract, 88% (1417/1609) for eyes with prevalent cataract
{,V .IDs8[ and 85% (211/249) for eyes with operated cataract (chisquared,
:2+,?#W
2 d.f. = 22.3), P < 0.001). Twenty-seven of the
|%p;4b operated eyes (11%) had visual acuities of less than 6/18
\q2:1X| (moderate vision impairment) (Fig. 2). A cause of this
QYl
Pr&O9 moderate visual impairment (but not the only cause) in four
Fog4m=b`g (15%) eyes was secondary to cataract surgery. Three of these
=~qQ?;on four eyes had undergone intracapsular cataract extraction
#J4{W84B and the fourth eye had an opaque posterior capsule. No one
#kho[`9 had bilateral vision impairment as a result of their cataract
+MHsdeGU1W surgery.
&`]Lg?J DISCUSSION
Q&Q$;s3|Y To our knowledge, this is the first paper to systematically
.
#+ N?D< assess the prevalence of current cataract, previous cataract
j.}@ 9 surgery, predictors of unoperated cataract and the outcomes
Ii*tux!S of cataract surgery in a population-based sample. The Visual
"e)C.#3 Impairment Project is unique in that the sampling frame and
q oA?
high response rate have ensured that the study population is
'+%<\.$ representative of Australians aged 40 years and over. Therefore,
,Z_aZD4 these data can be used to plan age-related cataract
PIo8m f/ services throughout Australia.
397IbZ\ We found the rate of any cataract in those over the age
whoM$ & of 40 years to be 22%. Although relatively high, this rate is
=x_~7 Xc{ significantly less than was reported in a number of previous
/y2)<{{I studies,2,4,6 with the exception of the Casteldaccia Eye
9n\b!*x Study.5 However, it is difficult to compare rates of cataract
~tw#Q
between studies because of different methodologies and
@^O+ulLJ,] cataract definitions employed in the various studies, as well
}3%L3v& as the different age structures of the study populations.
Un~
}M/ Other studies have used less conservative definitions of
6ct'O**k*& cataract, thus leading to higher rates of cataract as defined.
XWuHH;~*L In most large epidemiologic studies of cataract, visual acuity
t9C.|6X has not been included in the definition of cataract.
VuU{7: Therefore, the prevalence of cataract may not reflect the
+VE]
.*T actual need for cataract surgery in the community.
>
14x.c 80 McCarty et al.
2oO&8:`tv Table 2. Prevalence of previous cataract by age, gender and cohort
Oh&k{DWE$ Age group Gender Urban Rural Nursing home Weighted total
9/yE\p. (years) (%) (%) (%)
hxT{!g 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
WP}NHz4H Female 0.00 0.00 0.00 0.00 (
btG+Ak+K* 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
<< XWL: Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
_ Vo35kA 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
ZcQ@%XY3~ Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
Y|3n^%I 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
SJ%h.u@&@F Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
gfPR3%EXs 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
CAJ]@P#Xj+ Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
}w|a^=HAp 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
izvwXC Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
_U<r
@ Age-standardized
.7`c(9< (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)
p~evPTHnrX Figure 2. Visual acuity in eyes that had undergone cataract
#Rj&PzBe surgery, n = 249. h, Presenting; j, best-corrected.
@dHQ}Ni Operated and unoperated cataract in Australia 81
R2Y.s^ The weighted prevalence of prior cataract surgery in the
a49xf^{1"i Visual Impairment Project (3.6%) was similar to the crude
|z
8Wh rate in the Beaver Dam Eye Study4 (3.1%), but less than the
4\pUA4 crude rate in the Blue Mountains Eye Study6 (6.0%).
Z'cL"n\9R] However, the age-standardized rate in the Blue Mountains
>s;>"] Eye Study (standardized to the age distribution of the urban
+\yQZ{4'@ Visual Impairment Project cohort) was found to be less than
Q|]
9 the Visual Impairment Project (standardized rate = 1.36%,
?H0"*8C?Y 95% CL 1.25, 1.47). The incidence of cataract surgery in
gc[BP>tl\ Australia has exceeded population growth.1 This is due,
qHf8z;lc perhaps, to advances in surgical techniques and lens
wticA#mb implants that have changed the risk–benefit ratio.
$8;`6o` The Global Initiative for the Elimination of Avoidable
RK\$>KFE Blindness, sponsored by the World Health Organization,
?(2^lH~6h states that cataract surgical services should be provided that
S uo ‘have a high success rate in terms of visual outcome and
Wu|AN
c improved quality of life’,17 although the ‘high success rate’ is
0)HZ5^J not defined. Population- and clinic-based studies conducted
NU/:jr.W# in the United States have demonstrated marked improvement
^,sKj- in visual acuity following cataract surgery.18–20 We
nm{J found that 85% of eyes that had undergone cataract extraction
Qs
#7<NQ had visual acuity of 6/12 or better. Previously, we have
Sf"]enwB shown that participants with prevalent cataract in this
<
/\y<]b cohort are more likely to express dissatisfaction with their
Re]7G.y current vision than participants without cataract or participants
Cj3C%W with prior cataract surgery.21 In a national study in the
s F!nSr United States, researchers found that the change in patients’
>oasA2S ratings of their vision difficulties and satisfaction with their
fKQq]&~
H vision after cataract surgery were more highly related to
>u/ T`$ their change in visual functioning score than to their change
D)){"Q!b in visual acuity.19 Furthermore, improvement in visual function
>j}.~$6dj_ has been shown to be associated with improvement in
=ec"G
2$?" overall quality of life.22
[~UCYYl A recent review found that the incidence of visually
TBr@F|RXiO significant posterior capsule opacification following
2nkUvb%= cataract surgery to be greater than 25%.23 We found 36%
qpZR-O capsulotomy in our population and that this was associated
uYy&<_r with visual acuity similar to that of eyes with a clear
A
.>L>uR capsule, but significantly better than that of eyes with an
s!eB8lkcT opaque capsule.
m{{
8#@g A number of studies have shown that the demand and
JR^#NefJ timing of cataract surgery vary according to visual acuity,
j _p|>f<} degree of handicap and socioeconomic factors.8–10,24,25 We
w\(;>e@ have also shown previously that ophthalmologists are more
alz2F.%Y likely to refer a patient for cataract surgery if the patient is
~3r}6,% employed and less likely to refer a nursing home resident.7
+L>?kr[i[ In the Visual Impairment Project, we did not find that any
*r|)@K| particular subgroup of the population was at greater risk of
\Zbi`
;m? having unoperated cataract. Universal access to health care
vzPuk|q3 in Australia may explain the fact that people without
HI%#S&d Medicare are more likely to delay cataract operations in the
.Mz'h9@ USA,8 but not having private health insurance is not associated
%9Y3jB",2 with unoperated cataract in Australia.
[rf.& In summary, cataract is a significant public health problem
1C]mxV=% in that one in four people in their 80s will have had cataract
]46#u=y~3 surgery. The importance of age-related cataract surgery will
LktH*ePO increase further with the ageing of the population: the
3,[#%}1(S number of people over age 60 years is expected to double in
`%nj$-W: the next 20 years. Cataract surgery services are well
/@`kM'1:
accessed by the Victorian population and the visual outcomes
h.WvPZ2U of cataract surgery have been shown to be very good.
q{E44
eQ7F These data can be used to plan for age-related cataract
T=D|
jt surgical services in Australia in the future as the need for
7v{s?h->$ cataract extractions increases.
c3]X#Qa#m$ ACKNOWLEDGEMENTS
2ms@CQy(00 The Visual Impairment Project was funded in part by grants
b<1+q{0r from the Victorian Health Promotion Foundation, the
Yv ZcG3@c3 National Health and Medical Research Council, the Ansell
2?./S)x) Ophthalmology Foundation, the Dorothy Edols Estate and
`Eq~W@';Q0 the Jack Brockhoff Foundation. Dr McCarty is the recipient
'#Pg:v_ of a Wagstaff Fellowship in Ophthalmology from the Royal
(m%A>e
B Victorian Eye and Ear Hospital.
DJ.n8hne REFERENCES
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