ABSTRACT
P@-R5
GK Purpose: To quantify the prevalence of cataract, the outcomes
RNl\`>Cz of cataract surgery and the factors related to
B0NN>)h unoperated cataract in Australia.
Ds;Rb6WcnY Methods: Participants were recruited from the Visual
Z,(%v.d Impairment Project: a cluster, stratified sample of more than
d+1L5}Jn 5000 Victorians aged 40 years and over. At examination
pC55Ec< sites interviews, clinical examinations and lens photography
U_.n=d ~B were performed. Cataract was defined in participants who
@m }rQT had: had previous cataract surgery, cortical cataract greater
8UjCX[v than 4/16, nuclear greater than Wilmer standard 2, or
z[_R"+ posterior subcapsular greater than 1 mm2.
Xt
nIK Results: The participant group comprised 3271 Melbourne
q\-xg*' residents, 403 Melbourne nursing home residents and 1473
^Osd/g rural residents.The weighted rate of any cataract in Victoria
1"*Nb5s was 21.5%. The overall weighted rate of prior cataract
m,xy4 surgery was 3.79%. Two hundred and forty-nine eyes had
>Lo6='G had prior cataract surgery. Of these 249 procedures, 49
2{jtQlc (20%) were aphakic, 6 (2.4%) had anterior chamber
]Hv*^Bak intraocular lenses and 194 (78%) had posterior chamber
9F-ViDI. intraocular lenses.Two hundred and eleven of these operated
Cnb[t[hk+j eyes (85%) had best-corrected visual acuity of 6/12 or
D>!v_v6 better, the legal requirement for a driver’s license.Twentyseven
P\ Pc/[
Z7 (11%) had visual acuity of less than 6/18 (moderate
h7Shl<f vision impairment). Complications of cataract surgery
0KNH=;d} caused reduced vision in four of the 27 eyes (15%), or 1.9%
b{9HooQ{ of operated eyes. Three of these four eyes had undergone
m
bB\~n intracapsular cataract extraction and the fourth eye had an
>=]NO'?O opaque posterior capsule. No one had bilateral vision
{HE.mHy impairment as a result of cataract surgery. Surprisingly, no
}lrfO_ particular demographic factors (such as age, gender, rural
g,{Ei]$>I residence, occupation, employment status, health insurance
#lLn='4 status, ethnicity) were related to the presence of unoperated
7csl1|U cataract.
@$N*lrM2 Conclusions: Although the overall prevalence of cataract is
V2<k0@y quite high, no particular subgroup is systematically underserviced
7Vof7Y < in terms of cataract surgery. Overall, the results of
Bm2}\KOI cataract surgery are very good, with the majority of eyes
)f_"`FH0d achieving driving vision following cataract extraction.
AQ_#uxI'oa Key words: cataract extraction, health planning, health
;Wp`th!F services accessibility, prevalence
hVQ+
J!qD INTRODUCTION
!:!@dC%8_ Cataract is the leading cause of blindness worldwide and, in
rE'
%MiIK Australia, cataract extractions account for the majority of all
^LQ lfd ophthalmic procedures.1 Over the period 1985–94, the rate
Qnu&GBM of cataract surgery in Australia was twice as high as would be
O#89M% expected from the growth in the elderly population.1
6iAc@ Although there have been a number of studies reporting
pCud`
:o" the prevalence of cataract in various populations,2–6 there is
>GF(.:7 little information about determinants of cataract surgery in
HS|
g
the population. A previous survey of Australian ophthalmologists
'yAoZ P\| showed that patient concern and lifestyle, rather
DI
cyXZH< than visual acuity itself, are the primary factors for referral
bNPjefBF for cataract surgery.7 This supports prior research which has
1:~m)"?I_^ shown that visual acuity is not a strong predictor of need for
KE|u}M@v6 cataract surgery.8,9 Elsewhere, socioeconomic status has
+cplM5X been shown to be related to cataract surgery rates.10
vp}>#& To appropriately plan health care services, information is
=
;-ju@d needed about the prevalence of age-related cataract in the
5a/
A_..+I community as well as the factors associated with cataract
'\vmfp= surgery. The purpose of this study is to quantify the prevalence
#I@[^^Vw of any cataract in Australia, to describe the factors
e+=G-u5}- related to unoperated cataract in the community and to
!j\&BAxTEk describe the visual outcomes of cataract surgery.
T>:g
ME METHODS
%:8q7PN| Study population
n<(5B|~y Details about the study methodology for the Visual
U3R`mHr0 Impairment Project have been published previously.11
d'@H@ Briefly, cluster sampling within three strata was employed to
Fl|&eO,e recruit subjects aged 40 years and over to participate.
,Z\,IRn Within the Melbourne Statistical Division, nine pairs of
!z6/.>QJ~ census collector districts were randomly selected. Fourteen
t6>Qe nursing homes within a 5 km radius of these nine test sites
d4=u`2w were randomly chosen to recruit nursing home residents.
5r}(|86O/ Clinical and Experimental Ophthalmology (2000) 28, 77–82
K#pt8Q Original Article
ve/6-J!5Y. Operated and unoperated cataract in Australia
hI#M {cz Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
sf&K<C]( Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
x?&xz; n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
T%vbD*nt. Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au DB=cc 78 McCarty et al.
vT<wd# Finally, four pairs of census collector districts in four rural
>Zp]vK~s Victorian communities were randomly selected to recruit rural
qk{UO
< residents. A household census was conducted to identify
-`1L[-<d=/ eligible residents aged 40 years and over who had been a
z_0 lMX` resident at that address for at least 6 months. At the time of
\$Qm2XKrK the household census, basic information about age, sex,
^)]*10 country of birth, language spoken at home, education, use of
%cif0Td
corrective spectacles and use of eye care services was collected.
hl
~F1"q) Eligible residents were then invited to attend a local
B{i;+[ase examination site for a more detailed interview and examination.
4 sgwQ$m) The study protocol was approved by the Royal Victorian
S#z8H+' Eye and Ear Hospital Human Research Ethics Committee.
31\^9w__8 Assessment of cataract
xE[tD? M{ A standardized ophthalmic examination was performed after
S;<?nz3 pupil dilatation with one drop of 10% phenylephrine
oD2;Tdk hydrochloride. Lens opacities were graded clinically at the
&H>dE]Hq, time of the examination and subsequently from photos using
j %0_!*#3 the Wilmer cataract photo-grading system.12 Cortical and
Qz$Dv@*y\ posterior subcapsular (PSC) opacities were assessed on
uzA'D ~)P retroillumination and measured as the proportion (in 1/16)
DfFPGFv of pupil circumference occupied by opacity. For this analysis,
z=pV{' cortical cataract was defined as 4/16 or greater opacity,
(6^k;j PSC cataract was defined as opacity equal to or greater than
pU'sADC 1 mm2 and nuclear cataract was defined as opacity equal to
^$
bhmJYT or greater than Wilmer standard 2,12 independent of visual
;MI<J>s acuity. Examples of the minimum opacities defined as cortical,
n?tAa|_ nuclear and PSC cataract are presented in Figure 1.
<TuSU[] Bilateral congenital cataracts or cataracts secondary to
J>PV{N intraocular inflammation or trauma were excluded from the
=^M t#h." analysis. Two cases of bilateral secondary cataract and eight
B+sqEj- cases of bilateral congenital cataract were excluded from the
!AHm+C_=Lg analyses.
jU~%5R A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
RV(z>XM Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
0-HE, lv height set to an incident angle of 30° was used for examinations.
K),wAZI!7j Ektachrome® 200 ASA colour slide film (Eastman
DyZ90]N Kodak Company, Rochester, NY, USA) was used to photograph
\LXC269 the nuclear opacities. The cortical opacities were
qm8RRDG photographed with an Oxford® retroillumination camera
A6L}5#7- (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
lukV
G2wDL film (Eastman Kodak). Photographs were graded separately
/GaR& by two research assistants and discrepancies were adjudicated
r&DK> H by an independent reviewer. Any discrepancies
/XB1U[b between the clinical grades and the photograph grades were
<k5~z( resolved. Except in cases where photographs were missing,
W'$~mK\ the photograph grades were used in the analyses. Photograph
#!Fs[A5% grades were available for 4301 (84%) for cortical
d:''qgz` cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
q4N$.hpb for PSC cataract. Cataract status was classified according to
Yv-uC}e the severity of the opacity in the worse eye.
uBgHtjmae Assessment of risk factors
ZZ5yu* & A standardized questionnaire was used to obtain information
](D [T about education, employment and ethnic background.11
ja2]VbB Specific information was elicited on the occurrence, duration
W
=m_G]"L and treatment of a number of medical conditions,
ENzeVtw0 including ocular trauma, arthritis, diabetes, gout, hypertension
5KSsRq/8" and mental illness. Information about the use, dose and
IM/\t!*7 duration of tobacco, alcohol, analgesics and steriods were
BKEB,K=K@ collected, and a food frequency questionnaire was used to
< lrw7 T determine current consumption of dietary sources of antioxidants
!@X#{ and use of vitamin supplements.
OUPpz_y Data management and statistical analysis
V2.K*CpZ7 Data were collected either by direct computer entry with a
s@|?N+z questionnaire programmed in Paradox© (Carel Corporation,
u4'Lm+&O Ottawa, Canada) with internal consistency checks, or
);[`rXH_ on self-coding forms. Open-ended responses were coded at
4$"Lf'sH6 a later time. Data that were entered on the self-coded forms
:\Z0^{ were entered into a computer with double data entry and
Yy}aQF#M reconciliation of any inconsistencies. Data range and consistency
T9^i#8-^ checks were performed on the entire data set.
)94R\
f SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
ORoraEK employed for statistical analyses.
h(sD] N Ninety-five per cent confidence limits around the agespecific
"n:9JqPb rates were calculated according to Cochran13 to
P
dJ*'@~i account for the effect of the cluster sampling. Ninety-five
pLU>vQA per cent confidence limits around age-standardized rates
L!Ro`6|7; were calculated according to Breslow and Day.14 The strataspecific
w
<ID< data were weighted according to the 1996
k#.co~kS Australian Bureau of Statistics census data15 to reflect the
QEPmuG cataract prevalence in the entire Victorian population.
/iK )tl|X Univariate analyses with Student’s t-tests and chi-squared
;P_Zen tests were first employed to evaluate risk factors for unoperated
SXL6)pX cataract. Any factors with P < 0.10 were then fitted
0-9&d(L1g into a backwards stepwise logistic regression model. For the
Oq("E(z+f Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
Xw%
z
#6l final multivariate models, P < 0.05 was considered statistically
l>ttxYBa<d significant. Design effect was assessed through the use
NJp;t[v.^ of cluster-specific models and multivariate models. The
sDiYm}W design effect was assumed to be additive and an adjustment
`y\:3bQ4
made in the variance by adding the variance associated with
S92Dvw? the design effect prior to constructing the 95% confidence
zehF/HBzE limits.
+G~b-} RESULTS
4c% :?H@2 Study population
S:d `z' A total of 3271 (83%) of the Melbourne residents, 403
!qR(Rn (90%) Melbourne nursing home residents, and 1473 (92%)
!|!V}O rural residents participated. In general, non-participants did
rLnu\X=h$ not differ from participants.16 The study population was
09"~<W8 representative of the Victorian population and Australia as
)fa
a whole.
+$-a:zx`l The Melbourne residents ranged in age from 40 to
7 XY C.g 98 years (mean = 59) and 1511 (46%) were male. The
d_`Ze.^
Melbourne nursing home residents ranged in age from 46 to
Q6BWax| 101 years (mean = 82) and 85 (21%) were men. The rural
`{/=i|6 residents ranged in age from 40 to 103 years (mean = 60)
SbZk{lWcq and 701 (47.5%) were men.
b{oNV-<&{ Prevalence of cataract and prior cataract surgery
E'ZWSpP As would be expected, the rate of any cataract increases
p|((r?{ dramatically with age (Table 1). The weighted rate of any
_EY:vv cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
f|`{PP`\ Although the rates varied somewhat between the three
\DHCf4, strata, they were not significantly different as the 95% confidence
>GcFk&x limits overlapped. The per cent of cataractous eyes
%:y-"m1\u$ with best-corrected visual acuity of less than 6/12 was 12.5%
{R#nGsrt; (65/520) for cortical cataract, 18% for nuclear cataract
n Au>i< (97/534) and 14.4% (27/187) for PSC cataract. Cataract
|\ay^@N surgery also rose dramatically with age. The overall
}$o%^"[ weighted rate of prior cataract surgery in Victoria was
j7W_%Yk|E 3.79% (95% CL 2.97, 4.60) (Table 2).
;)kB
J @ Risk factors for unoperated cataract
^R\blJQ<^ Cases of cataract that had not been removed were classified
&M2x` as unoperated cataract. Risk factor analyses for unoperated
QdRMp
n}q cataract were not performed with the nursing home residents
brFOQU? as information about risk factor exposure was not
n`hSn41A available for this cohort. The following factors were assessed
JdAjKN in relation to unoperated cataract: age, sex, residence
vr;7p[~ (urban/rural), language spoken at home (a measure of ethnic
Oe#k|
integration), country of birth, parents’ country of birth (a
q^Z\V? measure of ethnicity), years since migration, education, use
|joGrWv4 of ophthalmic services, use of optometric services, private
wHCsEp( health insurance status, duration of distance glasses use,
iN><m| glaucoma, age-related maculopathy and employment status.
/ [19ITZ In this cross sectional study it was not possible to assess the
[L275]4n!] level of visual acuity that would predict a patient’s having
NUU}8a(K cataract surgery, as visual acuity data prior to cataract
_#+9)*A surgery were not available.
lC2xl( #! The significant risk factors for unoperated cataract in univariate
OlK2<
< analyses were related to: whether a participant had
LY
>JE6zTt ever seen an optometrist, seen an ophthalmologist or been
&A9+%kOk> diagnosed with glaucoma; and participants’ employment
N+tS:$V status (currently employed) and age. These significant
[brrziZ factors were placed in a backwards stepwise logistic regression
4 A<c@g2 model. The factors that remained significantly related
r~;N(CG to unoperated cataract were whether participants had ever
w"
e2}iE7 seen an ophthalmologist, seen an optometrist and been
Jq!($PdA diagnosed with glaucoma. None of the demographic factors
f6#H@
X were associated with unoperated cataract in the multivariate
-7`J(f.rYC model.
k (R4-"@ The per cent of participants with unoperated cataract
X*~YCF[_ who said that they were dissatisfied or very dissatisfied with
HI?>]zz| Operated and unoperated cataract in Australia 79
#7>CLjI Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
)Ga6O2
: Age group Sex Urban Rural Nursing home Weighted total
o i?ak
(years) (%) (%) (%)
l\5NuCgRY 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
9p.>L8 Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
<ZiO[dEV 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
m|k,8guG Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
-FI1$ 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
+D@R'$N Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
jt3SA
[cy 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
-'(:Sq,4o Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
GZ={G2@=I 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
q
mB@kbt Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
by<2hLB9Q 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
e#('`vGB Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
NO$Nl/XM Age-standardized
0#JBz\ (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)
NSq"\A\ aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
mAzW'Q4D their current vision was 30% (290/683), compared with 27%
2Kidbf (26/95) of participants with prior cataract surgery (chisquared,
[OcD#~drO 1 d.f. = 0.25, P = 0.62).
{aSq3C<r Outcomes of cataract surgery
f"Iyo:Wt Two hundred and forty-nine eyes had undergone prior
<G>PPf} cataract surgery. Of these 249 operated eyes, 49 (20%) were
Fo#*_y5\ left aphakic, 6 (2.4%) had anterior chamber intraocular
^Ram8fW lenses and 194 (78%) had posterior chamber intraocular
0"`skYJ@ lenses. The rate of capsulotomy in the eyes with intact
m5Kx}H~ posterior capsules was 36% (73/202). Fifteen per cent of
#7=LI\ eyes (17/114) with a clear posterior capsule had bestcorrected
0=B5
=qyw visual acuity of less than 6/12 compared with 43%
Vz*'^=(o& of eyes (6/14) with opaque capsules, and 15% of eyes
KfNXX>' (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
9YABr>
? P = 0.027).
B
}X#oA The percentage of eyes with best-corrected visual acuity
9:o3JGHSc of 6/12 or better was 96% (302/314) for eyes without
Xdt+\}\ cataract, 88% (1417/1609) for eyes with prevalent cataract
([~`{,sv and 85% (211/249) for eyes with operated cataract (chisquared,
27:x5g? 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
Oe`t!&v operated eyes (11%) had visual acuities of less than 6/18
7w, FA (moderate vision impairment) (Fig. 2). A cause of this
U5"Oh I moderate visual impairment (but not the only cause) in four
Hea<!zPH (15%) eyes was secondary to cataract surgery. Three of these
E6M: ^p*< four eyes had undergone intracapsular cataract extraction
8BDL{?Mu and the fourth eye had an opaque posterior capsule. No one
dL(|Y{4 had bilateral vision impairment as a result of their cataract
q;.]e#wvh surgery.
46Nf|~ DISCUSSION
6l'y To our knowledge, this is the first paper to systematically
->=++ assess the prevalence of current cataract, previous cataract
uszSFe]E surgery, predictors of unoperated cataract and the outcomes
-QDgr`%5 of cataract surgery in a population-based sample. The Visual
uW=NH;u Impairment Project is unique in that the sampling frame and
C&kl*nO high response rate have ensured that the study population is
!`o:+Gg@ representative of Australians aged 40 years and over. Therefore,
nD\os[ 3 these data can be used to plan age-related cataract
0z7mre^Q services throughout Australia.
7G/|e24 We found the rate of any cataract in those over the age
GK?
R76d of 40 years to be 22%. Although relatively high, this rate is
pVS2dwBqE significantly less than was reported in a number of previous
!!%[JR)cS studies,2,4,6 with the exception of the Casteldaccia Eye
a] =\h'S Study.5 However, it is difficult to compare rates of cataract
5l0rw)
between studies because of different methodologies and
} <4[(N cataract definitions employed in the various studies, as well
ok%!o+n
k. as the different age structures of the study populations.
e-3pg?M Other studies have used less conservative definitions of
v9lBk]c cataract, thus leading to higher rates of cataract as defined.
I A#*T` In most large epidemiologic studies of cataract, visual acuity
SoU'r]k1x has not been included in the definition of cataract.
l~TIFmHkh% Therefore, the prevalence of cataract may not reflect the
|#:dC # actual need for cataract surgery in the community.
p]z54 ~ 80 McCarty et al.
I@Z*Nu1L Table 2. Prevalence of previous cataract by age, gender and cohort
p6Dv;@)Yn Age group Gender Urban Rural Nursing home Weighted total
k5QD5/Ej
(years) (%) (%) (%)
vLFaZ^( 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
'a
g6B(0Z Female 0.00 0.00 0.00 0.00 (
-s%-*K+,W 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
R|J>8AL}BY Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
*r,&@UB 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
^
Xy$is3 Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
6+nMH
+[ 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
GHC?Tp Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
f@Rpb}zg+C 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
LF)a"Sh Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
T~~[a|bLa 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
,C,e/>+My Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
d?&!y]RS# Age-standardized
?WQ
d (95% CL) Combined 3.31 (2.70, 3.93) 4.36 (2.67, 6.06) 2.26 (0.82, 3.70) 3.79 (2.97, 4.60)
r;on0wm&B Figure 2. Visual acuity in eyes that had undergone cataract
a}qse5Fr surgery, n = 249. h, Presenting; j, best-corrected.
YUVc9PV)Ws Operated and unoperated cataract in Australia 81
lc3
S|4 The weighted prevalence of prior cataract surgery in the
O`[iz/7m Visual Impairment Project (3.6%) was similar to the crude
,KhMzE8_a rate in the Beaver Dam Eye Study4 (3.1%), but less than the
tk)>CK11 crude rate in the Blue Mountains Eye Study6 (6.0%).
/x:(SR2, However, the age-standardized rate in the Blue Mountains
o~o6S=4,} Eye Study (standardized to the age distribution of the urban
N?=qEX|R Visual Impairment Project cohort) was found to be less than
h%1~v$W` the Visual Impairment Project (standardized rate = 1.36%,
k99gjL` 95% CL 1.25, 1.47). The incidence of cataract surgery in
~ACP%QM= Australia has exceeded population growth.1 This is due,
gN, k/U8 perhaps, to advances in surgical techniques and lens
"ji$@b_\? implants that have changed the risk–benefit ratio.
Q k;Kn The Global Initiative for the Elimination of Avoidable
qJX+[PJ Blindness, sponsored by the World Health Organization,
BA1MGh states that cataract surgical services should be provided that
Wd^lt7(j ‘have a high success rate in terms of visual outcome and
a81!~1A improved quality of life’,17 although the ‘high success rate’ is
zJfK4o
not defined. Population- and clinic-based studies conducted
'Vm5Cs$ in the United States have demonstrated marked improvement
4/HY[FT in visual acuity following cataract surgery.18–20 We
J})$ found that 85% of eyes that had undergone cataract extraction
1!>bhH}{D had visual acuity of 6/12 or better. Previously, we have
5?3Isw`v2 shown that participants with prevalent cataract in this
V~J*49t&2J cohort are more likely to express dissatisfaction with their
Mt[Bq6}ZD current vision than participants without cataract or participants
;Na8_} with prior cataract surgery.21 In a national study in the
[j:}=:feQ United States, researchers found that the change in patients’
?jNF6z*M6 ratings of their vision difficulties and satisfaction with their
wGOMUWAt vision after cataract surgery were more highly related to
670J{b their change in visual functioning score than to their change
y3={NB+ in visual acuity.19 Furthermore, improvement in visual function
I" 8d5a} has been shown to be associated with improvement in
Y]+e
Df overall quality of life.22
ER~T'-YMS A recent review found that the incidence of visually
DL'd&;6 significant posterior capsule opacification following
%PQl
dPL8 cataract surgery to be greater than 25%.23 We found 36%
pG,<_N@P capsulotomy in our population and that this was associated
zQL!(2 with visual acuity similar to that of eyes with a clear
&Q'\WA' capsule, but significantly better than that of eyes with an
Wk/fB0
opaque capsule.
#joF{M{ A number of studies have shown that the demand and
SW,q}- timing of cataract surgery vary according to visual acuity,
W$z#ssr degree of handicap and socioeconomic factors.8–10,24,25 We
"t5
+* have also shown previously that ophthalmologists are more
u{g]gA8s likely to refer a patient for cataract surgery if the patient is
(y=dR1p employed and less likely to refer a nursing home resident.7
51&|t#8h In the Visual Impairment Project, we did not find that any
}7iUagN particular subgroup of the population was at greater risk of
ijvNmn1k having unoperated cataract. Universal access to health care
+7Sf8tg\ in Australia may explain the fact that people without
C}Rs[ Medicare are more likely to delay cataract operations in the
d-hbvLn USA,8 but not having private health insurance is not associated
p:Iw%eZ: with unoperated cataract in Australia.
K1;zMh In summary, cataract is a significant public health problem
CIIY|DI`l in that one in four people in their 80s will have had cataract
=ZG<BG_ surgery. The importance of age-related cataract surgery will
.JNcY]V# increase further with the ageing of the population: the
fG<Dh z@ number of people over age 60 years is expected to double in
$RpFxi
the next 20 years. Cataract surgery services are well
: @s8?eg accessed by the Victorian population and the visual outcomes
s5Pq$< of cataract surgery have been shown to be very good.
v,n); These data can be used to plan for age-related cataract
yU *u surgical services in Australia in the future as the need for
pV8[l) J cataract extractions increases.
KCE=|*6::| ACKNOWLEDGEMENTS
7@J
jjV The Visual Impairment Project was funded in part by grants
-4 8`#"xy from the Victorian Health Promotion Foundation, the
c2/"KT National Health and Medical Research Council, the Ansell
%y
eu" Ophthalmology Foundation, the Dorothy Edols Estate and
[Uswf3 the Jack Brockhoff Foundation. Dr McCarty is the recipient
D2{L= of a Wagstaff Fellowship in Ophthalmology from the Royal
V)=Z6 ti Victorian Eye and Ear Hospital.
18jJzYawh REFERENCES
;;M"hI3@ 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
AHq M7+r9 Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
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