ABSTRACT
o93`|yWl Purpose: To quantify the prevalence of cataract, the outcomes
/
oriW;OF of cataract surgery and the factors related to
7x@A%2J unoperated cataract in Australia.
U-|NY Methods: Participants were recruited from the Visual
9^j &VmF Impairment Project: a cluster, stratified sample of more than
{DR`;ea])1 5000 Victorians aged 40 years and over. At examination
RRI"d~~F6 sites interviews, clinical examinations and lens photography
PbmDNKEh{ were performed. Cataract was defined in participants who
v&=gF/$ had: had previous cataract surgery, cortical cataract greater
~/P&Tub^ than 4/16, nuclear greater than Wilmer standard 2, or
*FM Mjz posterior subcapsular greater than 1 mm2.
0:T|S>FsAm Results: The participant group comprised 3271 Melbourne
/C6k+0ApMT residents, 403 Melbourne nursing home residents and 1473
w/kt3Lw rural residents.The weighted rate of any cataract in Victoria
.dav8n* was 21.5%. The overall weighted rate of prior cataract
W' s surgery was 3.79%. Two hundred and forty-nine eyes had
^3UGV*Ypk had prior cataract surgery. Of these 249 procedures, 49
>Vwc3d (20%) were aphakic, 6 (2.4%) had anterior chamber
H(Z88.OM intraocular lenses and 194 (78%) had posterior chamber
4B^ZnFJ%m intraocular lenses.Two hundred and eleven of these operated
{o>j6RS\ eyes (85%) had best-corrected visual acuity of 6/12 or
!Y[lQXv better, the legal requirement for a driver’s license.Twentyseven
eb =D/ (11%) had visual acuity of less than 6/18 (moderate
hX=A)73( vision impairment). Complications of cataract surgery
cj1cZ- caused reduced vision in four of the 27 eyes (15%), or 1.9%
LL3#5AA"k| of operated eyes. Three of these four eyes had undergone
6e[VgN-s intracapsular cataract extraction and the fourth eye had an
[@5Ytv H opaque posterior capsule. No one had bilateral vision
SgS~ {4Zx* impairment as a result of cataract surgery. Surprisingly, no
2u5|8 particular demographic factors (such as age, gender, rural
(w}H]LQ residence, occupation, employment status, health insurance
<psZQdH status, ethnicity) were related to the presence of unoperated
U15H@h cataract.
E( Z8 Conclusions: Although the overall prevalence of cataract is
Z7= `VNHc quite high, no particular subgroup is systematically underserviced
<y?r!l=Am in terms of cataract surgery. Overall, the results of
C,v(:ZE$J7 cataract surgery are very good, with the majority of eyes
!;KCU^9 achieving driving vision following cataract extraction.
]3X@
_NYj Key words: cataract extraction, health planning, health
-(~!Jo_*' services accessibility, prevalence
-@0GcUE:r INTRODUCTION
U
G~b a Cataract is the leading cause of blindness worldwide and, in
v%iof1 T'
Australia, cataract extractions account for the majority of all
f)^_|8 ophthalmic procedures.1 Over the period 1985–94, the rate
]zWon~ of cataract surgery in Australia was twice as high as would be
V 7Ek-2M expected from the growth in the elderly population.1
V4KMOYqm Although there have been a number of studies reporting
Q|D @Yd\ the prevalence of cataract in various populations,2–6 there is
d~JKH&x< little information about determinants of cataract surgery in
+P
cmJ the population. A previous survey of Australian ophthalmologists
@CZ
T showed that patient concern and lifestyle, rather
N<IT w/@^ than visual acuity itself, are the primary factors for referral
^$'z!+QRM for cataract surgery.7 This supports prior research which has
.ZJRO>S shown that visual acuity is not a strong predictor of need for
2C9V|[U, cataract surgery.8,9 Elsewhere, socioeconomic status has
,Q
HU_jt been shown to be related to cataract surgery rates.10
-6n K<e` To appropriately plan health care services, information is
HLV2~5Txc needed about the prevalence of age-related cataract in the
[&#/]Ul' community as well as the factors associated with cataract
woD>!r>) surgery. The purpose of this study is to quantify the prevalence
ck.w
5|$
of any cataract in Australia, to describe the factors
4'!c*@Y
related to unoperated cataract in the community and to
TwVlg; describe the visual outcomes of cataract surgery.
@AIaC-,~] METHODS
>76\nGO Study population
:"xzj<( Details about the study methodology for the Visual
w(/aiV Impairment Project have been published previously.11
}l],.J\BGX Briefly, cluster sampling within three strata was employed to
~s]iy9i recruit subjects aged 40 years and over to participate.
[g:$K5\64 Within the Melbourne Statistical Division, nine pairs of
@M5#S7q"; census collector districts were randomly selected. Fourteen
p4-o/8rO nursing homes within a 5 km radius of these nine test sites
O]1y0BOQ were randomly chosen to recruit nursing home residents.
Z`KC%!8K Clinical and Experimental Ophthalmology (2000) 28, 77–82
%|oJ>+ Original Article
17G'jiYH Operated and unoperated cataract in Australia
.tz
G_ Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
or';A'k Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
F=a<~EpZ n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
ZGYr$C~ Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au &'}/f5s| 78 McCarty et al.
f=mZu1(FZ Finally, four pairs of census collector districts in four rural
glF; eT Victorian communities were randomly selected to recruit rural
qIIv6''5@ residents. A household census was conducted to identify
X .5aMm eligible residents aged 40 years and over who had been a
( 8c9 /7h resident at that address for at least 6 months. At the time of
0QOBL'{7) the household census, basic information about age, sex,
'zGo?
a country of birth, language spoken at home, education, use of
pt?q#EfFJ corrective spectacles and use of eye care services was collected.
+i2}/s@JJ Eligible residents were then invited to attend a local
B9H@
e#[ examination site for a more detailed interview and examination.
}` ! =
m The study protocol was approved by the Royal Victorian
9)gC6IiW Eye and Ear Hospital Human Research Ethics Committee.
2VJR$Pao Assessment of cataract
!Y\D?rKZ A standardized ophthalmic examination was performed after
0Pe>Es|^A# pupil dilatation with one drop of 10% phenylephrine
pFHz"
] hydrochloride. Lens opacities were graded clinically at the
~(
IB0=A{v time of the examination and subsequently from photos using
Lg*B>= the Wilmer cataract photo-grading system.12 Cortical and
}=8B* posterior subcapsular (PSC) opacities were assessed on
4@ML3d/ retroillumination and measured as the proportion (in 1/16)
S&\L-@ of pupil circumference occupied by opacity. For this analysis,
K/3)g9Z&io cortical cataract was defined as 4/16 or greater opacity,
Qe5U<3{JZ PSC cataract was defined as opacity equal to or greater than
!/3B3cG 1 mm2 and nuclear cataract was defined as opacity equal to
j.L-{6_s>~ or greater than Wilmer standard 2,12 independent of visual
PUBWZ^63 acuity. Examples of the minimum opacities defined as cortical,
e*;c(3>( nuclear and PSC cataract are presented in Figure 1.
/s[l-1zW Bilateral congenital cataracts or cataracts secondary to
<B6&I$Wc+ intraocular inflammation or trauma were excluded from the
(s7;^)}zx analysis. Two cases of bilateral secondary cataract and eight
l: <?{)N` cases of bilateral congenital cataract were excluded from the
JNa"8 analyses.
fbL\?S,w A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
bV$)!]V Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
krC{ed height set to an incident angle of 30° was used for examinations.
Mc%Nf$XQ Ektachrome® 200 ASA colour slide film (Eastman
fe_yqIdk Kodak Company, Rochester, NY, USA) was used to photograph
]zQo>W$ the nuclear opacities. The cortical opacities were
E
gal4 photographed with an Oxford® retroillumination camera
bBS,-vN (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
J]G?
Rc film (Eastman Kodak). Photographs were graded separately
x7<\]
94 by two research assistants and discrepancies were adjudicated
'`XX
"_k3 by an independent reviewer. Any discrepancies
?}RSwl
between the clinical grades and the photograph grades were
DV\`Wv resolved. Except in cases where photographs were missing,
N\#MwLm the photograph grades were used in the analyses. Photograph
*hQTO=WF grades were available for 4301 (84%) for cortical
>9q&PEc cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
mN>h5G>a for PSC cataract. Cataract status was classified according to
5fm?Lxr&? the severity of the opacity in the worse eye.
9
P~\Mpk Assessment of risk factors
OnF3l Cmu A standardized questionnaire was used to obtain information
HE'2"t[a about education, employment and ethnic background.11
dd\n8f Specific information was elicited on the occurrence, duration
=9z[[dQ|L and treatment of a number of medical conditions,
m^H21P"z including ocular trauma, arthritis, diabetes, gout, hypertension
+> WM[o^I and mental illness. Information about the use, dose and
;[W"mlM duration of tobacco, alcohol, analgesics and steriods were
XP1~d>j collected, and a food frequency questionnaire was used to
:k3Nt5t! determine current consumption of dietary sources of antioxidants
V\{tmDE and use of vitamin supplements.
(vB<%l.& Data management and statistical analysis
m<w"T7 Data were collected either by direct computer entry with a
TP"1\O questionnaire programmed in Paradox© (Carel Corporation,
K\$J4~EtG Ottawa, Canada) with internal consistency checks, or
?@6/E<-Z$
on self-coding forms. Open-ended responses were coded at
'/$d0`3B> a later time. Data that were entered on the self-coded forms
i@B[ eta were entered into a computer with double data entry and
MUA%^)#u4Q reconciliation of any inconsistencies. Data range and consistency
$ KRI'4 checks were performed on the entire data set.
!Yw3 d SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
8-lOB employed for statistical analyses.
oXDN+4ge Ninety-five per cent confidence limits around the agespecific
fn
NYX]_bk rates were calculated according to Cochran13 to
m1IKVa7-\} account for the effect of the cluster sampling. Ninety-five
A^RR@D per cent confidence limits around age-standardized rates
v0kqu were calculated according to Breslow and Day.14 The strataspecific
J8"[6vI d~ data were weighted according to the 1996
Qq@G\eRo Australian Bureau of Statistics census data15 to reflect the
NO0"* c ; cataract prevalence in the entire Victorian population.
fsEzpUY:{W Univariate analyses with Student’s t-tests and chi-squared
I`w4Xrd tests were first employed to evaluate risk factors for unoperated
Z1h
] cataract. Any factors with P < 0.10 were then fitted
AxZD-|. into a backwards stepwise logistic regression model. For the
O4g+D#Lu Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
Wfz\`y final multivariate models, P < 0.05 was considered statistically
{w8 NN-n significant. Design effect was assessed through the use
)OLq_':^@ of cluster-specific models and multivariate models. The
}HG#s4 design effect was assumed to be additive and an adjustment
+e-,ST&w( made in the variance by adding the variance associated with
WH$e2[+Y the design effect prior to constructing the 95% confidence
x%< limits.
1Fe^Qb5G RESULTS
S#b-awk Study population
>;#=gM A total of 3271 (83%) of the Melbourne residents, 403
k78Vh$AA6% (90%) Melbourne nursing home residents, and 1473 (92%)
';G1A rural residents participated. In general, non-participants did
`' 153M] not differ from participants.16 The study population was
<|*'O5B representative of the Victorian population and Australia as
ur\qOX|{ a whole.
Nk;iiz+_p The Melbourne residents ranged in age from 40 to
M0'
a9.d 98 years (mean = 59) and 1511 (46%) were male. The
'&FjW-`"
G Melbourne nursing home residents ranged in age from 46 to
+"ueq 101 years (mean = 82) and 85 (21%) were men. The rural
o3Vn<Z$/Cl residents ranged in age from 40 to 103 years (mean = 60)
6QNs\Ucb+ and 701 (47.5%) were men.
/:\3 \{?0m Prevalence of cataract and prior cataract surgery
1mSaS4!"B As would be expected, the rate of any cataract increases
C*X
G_b ] dramatically with age (Table 1). The weighted rate of any
gFPi7 o1 cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
m7
%C#+67 Although the rates varied somewhat between the three
_ OaRY] strata, they were not significantly different as the 95% confidence
,&YTj> limits overlapped. The per cent of cataractous eyes
k]rLjcB with best-corrected visual acuity of less than 6/12 was 12.5%
tehUD& (65/520) for cortical cataract, 18% for nuclear cataract
'(#g1H3 (97/534) and 14.4% (27/187) for PSC cataract. Cataract
v8I{XU@% surgery also rose dramatically with age. The overall
'+*-s7o{ weighted rate of prior cataract surgery in Victoria was
S)A'Y]2X 3.79% (95% CL 2.97, 4.60) (Table 2).
Sg]
J7;] Risk factors for unoperated cataract
&s)0z)mR8& Cases of cataract that had not been removed were classified
=Z
sGT as unoperated cataract. Risk factor analyses for unoperated
CiL94Nkd9 cataract were not performed with the nursing home residents
A%vsno! as information about risk factor exposure was not
Ae?e 70bY available for this cohort. The following factors were assessed
0m+8P$)C% in relation to unoperated cataract: age, sex, residence
1Xyp/X2rI (urban/rural), language spoken at home (a measure of ethnic
#
4|9Fj?? integration), country of birth, parents’ country of birth (a
VG*'"y*%w measure of ethnicity), years since migration, education, use
3]n0 &MZAR of ophthalmic services, use of optometric services, private
-)<m
S health insurance status, duration of distance glasses use,
"L3Xd][ glaucoma, age-related maculopathy and employment status.
8,o17}NY, In this cross sectional study it was not possible to assess the
MFg'YA2
/ level of visual acuity that would predict a patient’s having
(Q-I8Y8l8 cataract surgery, as visual acuity data prior to cataract
Cj&$%sO1 surgery were not available.
K@@9:T$ The significant risk factors for unoperated cataract in univariate
3ViM ?p analyses were related to: whether a participant had
,.g}W~S) ever seen an optometrist, seen an ophthalmologist or been
cD{8|B* diagnosed with glaucoma; and participants’ employment
Lm.`+W5 status (currently employed) and age. These significant
[[qwaI factors were placed in a backwards stepwise logistic regression
z };ZxN model. The factors that remained significantly related
v3JPE])/ to unoperated cataract were whether participants had ever
<{019Oa seen an ophthalmologist, seen an optometrist and been
!*P&Eat diagnosed with glaucoma. None of the demographic factors
)o8g=7Jm were associated with unoperated cataract in the multivariate
*?8RXer model.
PZ34 *q The per cent of participants with unoperated cataract
?mOg@) wx who said that they were dissatisfied or very dissatisfied with
M}!A]@ Operated and unoperated cataract in Australia 79
cw+g
z!! Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
;,0lUcV Age group Sex Urban Rural Nursing home Weighted total
!"! ii$@ (years) (%) (%) (%)
l(Cf7o!
40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
5.k}{{+ Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
E&%jeR 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
5OB]x?4] Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
j@C0af 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
~Oh=
Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
l<2oklo5 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
$WNG07]tU Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
|yAK@Hl' 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
a
Qmfrx Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
k2OM="Ei} 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
ou;qO
5CT Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
DVzssPg Age-standardized
966<I56+ (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
\ 522,n` aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
,F}r@ their current vision was 30% (290/683), compared with 27%
sVcdj|j (26/95) of participants with prior cataract surgery (chisquared,
M,JA;a, _ 1 d.f. = 0.25, P = 0.62).
<N5rv3
s Outcomes of cataract surgery
^5>du~d Two hundred and forty-nine eyes had undergone prior
8;8YA1
@w cataract surgery. Of these 249 operated eyes, 49 (20%) were
+',^((o left aphakic, 6 (2.4%) had anterior chamber intraocular
.ujj:> lenses and 194 (78%) had posterior chamber intraocular
?k::tNv0 lenses. The rate of capsulotomy in the eyes with intact
=Pj@g/25u posterior capsules was 36% (73/202). Fifteen per cent of
U,38qKE eyes (17/114) with a clear posterior capsule had bestcorrected
FbBX}n visual acuity of less than 6/12 compared with 43%
mb~./.5F of eyes (6/14) with opaque capsules, and 15% of eyes
7 7^
"xsa (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
s~)L_ p P = 0.027).
J&
)#G@fRX The percentage of eyes with best-corrected visual acuity
DH/L`$ of 6/12 or better was 96% (302/314) for eyes without
UE
{,.s cataract, 88% (1417/1609) for eyes with prevalent cataract
+/w(K, and 85% (211/249) for eyes with operated cataract (chisquared,
2pjW,I!` 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
h*G
#<M operated eyes (11%) had visual acuities of less than 6/18
;n`
$+g:> (moderate vision impairment) (Fig. 2). A cause of this
?-d
Ain1w moderate visual impairment (but not the only cause) in four
fPOEVmj< (15%) eyes was secondary to cataract surgery. Three of these
A<2I! four eyes had undergone intracapsular cataract extraction
hc6.#~i and the fourth eye had an opaque posterior capsule. No one
^J0zXe -d had bilateral vision impairment as a result of their cataract
&7fY_~ )B surgery.
%
<^[j^j}o DISCUSSION
8i["
.9}G\ To our knowledge, this is the first paper to systematically
z;ULQ assess the prevalence of current cataract, previous cataract
70duk:Ri0 surgery, predictors of unoperated cataract and the outcomes
aN:HG)$@ of cataract surgery in a population-based sample. The Visual
@T5YsX]qb7 Impairment Project is unique in that the sampling frame and
xcw%RUC- high response rate have ensured that the study population is
=?wMESU representative of Australians aged 40 years and over. Therefore,
lD9%xCo9( these data can be used to plan age-related cataract
o*-h%Z. services throughout Australia.
Sy4
mZ}: We found the rate of any cataract in those over the age
7Nd*,DV_ of 40 years to be 22%. Although relatively high, this rate is
c]e`m6 significantly less than was reported in a number of previous
k\nH&nb studies,2,4,6 with the exception of the Casteldaccia Eye
^GE^Q\&D& Study.5 However, it is difficult to compare rates of cataract
*Yj~]E0`1 between studies because of different methodologies and
} /[_ cataract definitions employed in the various studies, as well
k& WS$R?u as the different age structures of the study populations.
Tt{U"EFO Other studies have used less conservative definitions of
-)4uYK* cataract, thus leading to higher rates of cataract as defined.
Hde]DK,d In most large epidemiologic studies of cataract, visual acuity
W\&WS"=~ has not been included in the definition of cataract.
:a#
F Therefore, the prevalence of cataract may not reflect the
L[CU actual need for cataract surgery in the community.
/&*m1EN#o 80 McCarty et al.
g@<sU0B Table 2. Prevalence of previous cataract by age, gender and cohort
zt-'
SY Age group Gender Urban Rural Nursing home Weighted total
c:3@[nF
~ (years) (%) (%) (%)
$7msL#E7 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
|P^]@om Female 0.00 0.00 0.00 0.00 (
=Dh$yC-Zr 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
G/NTe Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
KYnW7|* 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
;%BhhmR)[ Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
n^* >a 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
;[;)P tFz\ Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
U(rr vNt:t 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
X*TuQ\T Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
^;0~6uBEJr 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
9=Y,["br$_ Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
\?bwm&6+r Age-standardized
)$ ofl%+ (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)
i!CKA}
", Figure 2. Visual acuity in eyes that had undergone cataract
<{$ev&bQ surgery, n = 249. h, Presenting; j, best-corrected.
4y|xUO: Operated and unoperated cataract in Australia 81
P]!LN\[ The weighted prevalence of prior cataract surgery in the
E9yFREvQc Visual Impairment Project (3.6%) was similar to the crude
X)`(nj rate in the Beaver Dam Eye Study4 (3.1%), but less than the
wm); aWP crude rate in the Blue Mountains Eye Study6 (6.0%).
>/7KL2* However, the age-standardized rate in the Blue Mountains
M[:O( Eye Study (standardized to the age distribution of the urban
:NwMb^> Visual Impairment Project cohort) was found to be less than
:N^@a- the Visual Impairment Project (standardized rate = 1.36%,
]I{qp~^#n 95% CL 1.25, 1.47). The incidence of cataract surgery in
3v9gb,)y\ Australia has exceeded population growth.1 This is due,
S[W9G)KWp perhaps, to advances in surgical techniques and lens
^ 4u3Q implants that have changed the risk–benefit ratio.
8CHb~m@^$ The Global Initiative for the Elimination of Avoidable
/3)YWFZZc Blindness, sponsored by the World Health Organization,
K^!e-Xi6 states that cataract surgical services should be provided that
naec"Kut ‘have a high success rate in terms of visual outcome and
>>oASo improved quality of life’,17 although the ‘high success rate’ is
QOkE\ro not defined. Population- and clinic-based studies conducted
E3CiZ4=5 in the United States have demonstrated marked improvement
H j5WJ{p. in visual acuity following cataract surgery.18–20 We
Vu|Br found that 85% of eyes that had undergone cataract extraction
p|bc=`TD had visual acuity of 6/12 or better. Previously, we have
l5\B2 +}7 shown that participants with prevalent cataract in this
/%J&/2Wz cohort are more likely to express dissatisfaction with their
G1#Bb5q: current vision than participants without cataract or participants
yNhscAMNn with prior cataract surgery.21 In a national study in the
f>\bUmk( United States, researchers found that the change in patients’
@\%)'WU ratings of their vision difficulties and satisfaction with their
P`Hd*xh".j vision after cataract surgery were more highly related to
[6,]9|~ their change in visual functioning score than to their change
.R$+#_ in visual acuity.19 Furthermore, improvement in visual function
5C Y@R has been shown to be associated with improvement in
qrkRD*a overall quality of life.22
Ac5o K A recent review found that the incidence of visually
=BqaGXr significant posterior capsule opacification following
Ww'TCWk@ cataract surgery to be greater than 25%.23 We found 36%
eZR8<Z% capsulotomy in our population and that this was associated
ctc`^#q with visual acuity similar to that of eyes with a clear
#czyr@ capsule, but significantly better than that of eyes with an
fncwe ';? opaque capsule.
[/+dHW| A number of studies have shown that the demand and
sO{0hZkc timing of cataract surgery vary according to visual acuity,
|oBdryi degree of handicap and socioeconomic factors.8–10,24,25 We
OU)p)Y_z have also shown previously that ophthalmologists are more
g6@N PQ likely to refer a patient for cataract surgery if the patient is
VHgF#6' employed and less likely to refer a nursing home resident.7
.kB3jfw0, In the Visual Impairment Project, we did not find that any
k@t,[ particular subgroup of the population was at greater risk of
YA;8uMqh; having unoperated cataract. Universal access to health care
px
[1# * in Australia may explain the fact that people without
-aH?7HV} Medicare are more likely to delay cataract operations in the
G"U>fwFuK USA,8 but not having private health insurance is not associated
"f&i 251 with unoperated cataract in Australia.
n6%jhv9H In summary, cataract is a significant public health problem
j6R{ in that one in four people in their 80s will have had cataract
t7!>5e)C} surgery. The importance of age-related cataract surgery will
OuBMVn increase further with the ageing of the population: the
zW"3K
number of people over age 60 years is expected to double in
-EkDG]my the next 20 years. Cataract surgery services are well
#H|j-RM2 accessed by the Victorian population and the visual outcomes
5>1Y="B of cataract surgery have been shown to be very good.
P7
>C4rmQ These data can be used to plan for age-related cataract
^zWO[$n}tP surgical services in Australia in the future as the need for
IjB*myN. cataract extractions increases.
sen{f^U ACKNOWLEDGEMENTS
L$TKO,T The Visual Impairment Project was funded in part by grants
TNFm7}= from the Victorian Health Promotion Foundation, the
li_pM!dWU_ National Health and Medical Research Council, the Ansell
{ZsWZJ! Ophthalmology Foundation, the Dorothy Edols Estate and
Acq>M^
E3 the Jack Brockhoff Foundation. Dr McCarty is the recipient
xwH|ryfs,Z of a Wagstaff Fellowship in Ophthalmology from the Royal
DT(Zv2 Victorian Eye and Ear Hospital.
kG;\
i REFERENCES
v/TlXxfil 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
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