ABSTRACT
ya=51~ by" Purpose: To quantify the prevalence of cataract, the outcomes
/;1FZ<zU of cataract surgery and the factors related to
Y@eUvz unoperated cataract in Australia.
C~*m&,@TT^ Methods: Participants were recruited from the Visual
i:72FVo Impairment Project: a cluster, stratified sample of more than
-D(!B56_ 5000 Victorians aged 40 years and over. At examination
"AVc^> sites interviews, clinical examinations and lens photography
o6oYJ`PY were performed. Cataract was defined in participants who
e^QOn had: had previous cataract surgery, cortical cataract greater
I6_+3}Hm{ than 4/16, nuclear greater than Wilmer standard 2, or
~c"c9s+o posterior subcapsular greater than 1 mm2.
xC(PH?_ Results: The participant group comprised 3271 Melbourne
Z)~2{) residents, 403 Melbourne nursing home residents and 1473
&V$R@~x rural residents.The weighted rate of any cataract in Victoria
T7`Jtqf was 21.5%. The overall weighted rate of prior cataract
>8so'7( surgery was 3.79%. Two hundred and forty-nine eyes had
-|5&3HVz had prior cataract surgery. Of these 249 procedures, 49
"d'@IN (20%) were aphakic, 6 (2.4%) had anterior chamber
d
{4br intraocular lenses and 194 (78%) had posterior chamber
qM)^]2_- intraocular lenses.Two hundred and eleven of these operated
Qa=;Elp:[ eyes (85%) had best-corrected visual acuity of 6/12 or
!VW#hc\A5 better, the legal requirement for a driver’s license.Twentyseven
Tym!7H2 (11%) had visual acuity of less than 6/18 (moderate
Y
`wi=( vision impairment). Complications of cataract surgery
(`&g caused reduced vision in four of the 27 eyes (15%), or 1.9%
@({65 gJ* of operated eyes. Three of these four eyes had undergone
fXN;N&I intracapsular cataract extraction and the fourth eye had an
dFlx6H+R!0 opaque posterior capsule. No one had bilateral vision
x
AI<<[- impairment as a result of cataract surgery. Surprisingly, no
ty ~U~ particular demographic factors (such as age, gender, rural
<m!\Ma residence, occupation, employment status, health insurance
I?=Q
*og status, ethnicity) were related to the presence of unoperated
lH[N*9G( cataract.
ev>: 3_ s Conclusions: Although the overall prevalence of cataract is
:mij%nQ>$ quite high, no particular subgroup is systematically underserviced
&wJ"9pQ~6E in terms of cataract surgery. Overall, the results of
Kxg09\5i cataract surgery are very good, with the majority of eyes
\(Iy>L. achieving driving vision following cataract extraction.
3KGDS9I Key words: cataract extraction, health planning, health
)gE:@3 services accessibility, prevalence
B!:(*lF INTRODUCTION
!cfn%+0 Cataract is the leading cause of blindness worldwide and, in
|
.PLfc; Australia, cataract extractions account for the majority of all
TR#5V@e.m ophthalmic procedures.1 Over the period 1985–94, the rate
9s}--_k?F2 of cataract surgery in Australia was twice as high as would be
:Z<-J` expected from the growth in the elderly population.1
hHdC/mR
Although there have been a number of studies reporting
E@?jsN7 the prevalence of cataract in various populations,2–6 there is
# H4dmnV little information about determinants of cataract surgery in
"B.l j) the population. A previous survey of Australian ophthalmologists
"kMpa]<c-6 showed that patient concern and lifestyle, rather
IE3GM^7\ than visual acuity itself, are the primary factors for referral
mFT[[Z# for cataract surgery.7 This supports prior research which has
='~C$% shown that visual acuity is not a strong predictor of need for
EPyFM_k cataract surgery.8,9 Elsewhere, socioeconomic status has
Zcc6E2 been shown to be related to cataract surgery rates.10
gbF.Q7?$u To appropriately plan health care services, information is
tL D.e needed about the prevalence of age-related cataract in the
J|s4c`= community as well as the factors associated with cataract
Q+S>nL!*#1 surgery. The purpose of this study is to quantify the prevalence
4%B${zP(.} of any cataract in Australia, to describe the factors
"}EydG"= related to unoperated cataract in the community and to
Y]P]^3 describe the visual outcomes of cataract surgery.
F`'
e/ METHODS
1h|JKu0 Study population
'H+pwp"M@ Details about the study methodology for the Visual
qW),)i Impairment Project have been published previously.11
2uz<n}IV Briefly, cluster sampling within three strata was employed to
UA}k"uM recruit subjects aged 40 years and over to participate.
2Ui)'0 Within the Melbourne Statistical Division, nine pairs of
x2;92I{5C, census collector districts were randomly selected. Fourteen
BH\qm
(X nursing homes within a 5 km radius of these nine test sites
zf#V89!]C" were randomly chosen to recruit nursing home residents.
\S3C"P%w Clinical and Experimental Ophthalmology (2000) 28, 77–82
.BZw7
YV Original Article
v@[MX- ,8 Operated and unoperated cataract in Australia
R|`}z"4C Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
#BF(#1: Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
tPc '#. n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
,Epg&)wC] Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au |>Kf_b Y# 78 McCarty et al.
-_v[oqf$ Finally, four pairs of census collector districts in four rural
P6dIU/w Victorian communities were randomly selected to recruit rural
{ 6*h';~ residents. A household census was conducted to identify
H;%a1
eligible residents aged 40 years and over who had been a
%.[t(F resident at that address for at least 6 months. At the time of
e$fxC-sZ the household census, basic information about age, sex,
WADNr8. country of birth, language spoken at home, education, use of
Z'hW;^e%_z corrective spectacles and use of eye care services was collected.
e=QnGT*b5 Eligible residents were then invited to attend a local
>?'cZTNk] examination site for a more detailed interview and examination.
(F
+if The study protocol was approved by the Royal Victorian
Hi|' Eye and Ear Hospital Human Research Ethics Committee.
C
3b Assessment of cataract
#Q"el3P+q A standardized ophthalmic examination was performed after
xLP yV&j- pupil dilatation with one drop of 10% phenylephrine
U_y)p Cd hydrochloride. Lens opacities were graded clinically at the
[w
i " time of the examination and subsequently from photos using
*4dA(N\k" the Wilmer cataract photo-grading system.12 Cortical and
[89#8|+ posterior subcapsular (PSC) opacities were assessed on
NyFa2Ihd retroillumination and measured as the proportion (in 1/16)
g< M\zD of pupil circumference occupied by opacity. For this analysis,
Ul)2A cortical cataract was defined as 4/16 or greater opacity,
.TSj8, PSC cataract was defined as opacity equal to or greater than
"9>~O`l, 1 mm2 and nuclear cataract was defined as opacity equal to
1}}.e^Tsfr or greater than Wilmer standard 2,12 independent of visual
kzMCI)>" acuity. Examples of the minimum opacities defined as cortical,
s
'u6Ep/V nuclear and PSC cataract are presented in Figure 1.
=;9Wh!{ Bilateral congenital cataracts or cataracts secondary to
s0~a5Ti3 intraocular inflammation or trauma were excluded from the
x;?4A J{ analysis. Two cases of bilateral secondary cataract and eight
"@;q! B.qo cases of bilateral congenital cataract were excluded from the
=)
$a>N analyses.
Kzb&aOw A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
hHm&u^xY Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
*RD9gIze height set to an incident angle of 30° was used for examinations.
2G=Bav\n+ Ektachrome® 200 ASA colour slide film (Eastman
>2_BL5<S Kodak Company, Rochester, NY, USA) was used to photograph
Zz'(!h Uy the nuclear opacities. The cortical opacities were
V<$g^Vb photographed with an Oxford® retroillumination camera
vR
pMZ)e (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
; =ai]AYW film (Eastman Kodak). Photographs were graded separately
H[wJ; l by two research assistants and discrepancies were adjudicated
Oz#$
x by an independent reviewer. Any discrepancies
I,(m\NalK between the clinical grades and the photograph grades were
2asA]sY resolved. Except in cases where photographs were missing,
3ZGU?Z;R the photograph grades were used in the analyses. Photograph
mT
<4@RrB grades were available for 4301 (84%) for cortical
E{[c8l2B cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
>eQ;\j for PSC cataract. Cataract status was classified according to
G"T)+!6t the severity of the opacity in the worse eye.
9$c0<~B\ Assessment of risk factors
T^B&GgW A standardized questionnaire was used to obtain information
iA3d[%tBb about education, employment and ethnic background.11
yv=LT~ Specific information was elicited on the occurrence, duration
?7 e|gpQ| and treatment of a number of medical conditions,
XaW@CW including ocular trauma, arthritis, diabetes, gout, hypertension
Z$ Fh4 and mental illness. Information about the use, dose and
'g$~ij ;x duration of tobacco, alcohol, analgesics and steriods were
T
OdH collected, and a food frequency questionnaire was used to
)HNbWGu
determine current consumption of dietary sources of antioxidants
jz
QmYcd and use of vitamin supplements.
l~!Tnp\M Data management and statistical analysis
C(Ujx=G+3 Data were collected either by direct computer entry with a
I~
\j%zD questionnaire programmed in Paradox© (Carel Corporation,
-%*>z'|{ Ottawa, Canada) with internal consistency checks, or
}`{>]2 on self-coding forms. Open-ended responses were coded at
7Oe |:Z a later time. Data that were entered on the self-coded forms
rVowHP were entered into a computer with double data entry and
?`V%[~4_I reconciliation of any inconsistencies. Data range and consistency
zuUf:%k}I checks were performed on the entire data set.
yx"xb
Cc# SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
q4@n
pbx employed for statistical analyses.
.\M@oF
Ninety-five per cent confidence limits around the agespecific
Rcs7 'q5 rates were calculated according to Cochran13 to
fq
ZqPcT0 account for the effect of the cluster sampling. Ninety-five
)
[yM4QFl per cent confidence limits around age-standardized rates
85Zy0
l were calculated according to Breslow and Day.14 The strataspecific
=;!C7VS data were weighted according to the 1996
ke_Dd? Australian Bureau of Statistics census data15 to reflect the
c) Zid1 cataract prevalence in the entire Victorian population.
_?
#}@? Univariate analyses with Student’s t-tests and chi-squared
&MsnQP tests were first employed to evaluate risk factors for unoperated
^eQK.B
( cataract. Any factors with P < 0.10 were then fitted
<^6|ZgR into a backwards stepwise logistic regression model. For the
Os'
7h Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
h~{TCK+I final multivariate models, P < 0.05 was considered statistically
g+;m?VJ significant. Design effect was assessed through the use
]n1@!qa48 of cluster-specific models and multivariate models. The
[U@#whE O design effect was assumed to be additive and an adjustment
cdVh_"[ made in the variance by adding the variance associated with
Q4\EI=4P] the design effect prior to constructing the 95% confidence
"f/lm 2< limits.
d]6.$"\"p RESULTS
hz{=@jX Study population
CM?dB$AwX A total of 3271 (83%) of the Melbourne residents, 403
P,lKa. (90%) Melbourne nursing home residents, and 1473 (92%)
LnP={s rural residents participated. In general, non-participants did
Gh}sk-Xk= not differ from participants.16 The study population was
pe$"
nUy| representative of the Victorian population and Australia as
~6L\9B) a whole.
d?^bCf+< The Melbourne residents ranged in age from 40 to
nylrF"'e 98 years (mean = 59) and 1511 (46%) were male. The
`6;%HbP$W+ Melbourne nursing home residents ranged in age from 46 to
Y5e6|b| 101 years (mean = 82) and 85 (21%) were men. The rural
0)n#$d> residents ranged in age from 40 to 103 years (mean = 60)
gBb+Q, and 701 (47.5%) were men.
N@Pf \D Prevalence of cataract and prior cataract surgery
\g&P5 As would be expected, the rate of any cataract increases
ovJwor dramatically with age (Table 1). The weighted rate of any
a[d6@! cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
MebLY $&8 Although the rates varied somewhat between the three
%~Vgz(/ strata, they were not significantly different as the 95% confidence
H:byCFN- limits overlapped. The per cent of cataractous eyes
0Snl_@s with best-corrected visual acuity of less than 6/12 was 12.5%
>
__t 2 (65/520) for cortical cataract, 18% for nuclear cataract
x&>zD0\
:\ (97/534) and 14.4% (27/187) for PSC cataract. Cataract
'Vq_/g!?1 surgery also rose dramatically with age. The overall
$j=c;+W weighted rate of prior cataract surgery in Victoria was
{ ]Tb 3.79% (95% CL 2.97, 4.60) (Table 2).
6t@kft>Nv Risk factors for unoperated cataract
Mg3>/! Cases of cataract that had not been removed were classified
b.HfxYt( as unoperated cataract. Risk factor analyses for unoperated
('k;Ikut cataract were not performed with the nursing home residents
<NRW^#g<x as information about risk factor exposure was not
O#Y;s;)i" available for this cohort. The following factors were assessed
9w\yWxl in relation to unoperated cataract: age, sex, residence
^APPWQUl (urban/rural), language spoken at home (a measure of ethnic
K??(>0Qr}r integration), country of birth, parents’ country of birth (a
^yLiyR e\ measure of ethnicity), years since migration, education, use
'Pk14`/ of ophthalmic services, use of optometric services, private
xZ2^lsY health insurance status, duration of distance glasses use,
+<qmVW^X glaucoma, age-related maculopathy and employment status.
YT:])[gVV In this cross sectional study it was not possible to assess the
$TU)O^c level of visual acuity that would predict a patient’s having
jm~(O
Lg cataract surgery, as visual acuity data prior to cataract
w]2tb surgery were not available.
n`'v8 `a] The significant risk factors for unoperated cataract in univariate
VL6_in( analyses were related to: whether a participant had
}?PvNK]", ever seen an optometrist, seen an ophthalmologist or been
(H=7 ( diagnosed with glaucoma; and participants’ employment
gN"Abc status (currently employed) and age. These significant
Y ;qA@| factors were placed in a backwards stepwise logistic regression
~r(/)w\ model. The factors that remained significantly related
Hzos$1DJ to unoperated cataract were whether participants had ever
wD9Gl.uQ seen an ophthalmologist, seen an optometrist and been
WsHC%+\' diagnosed with glaucoma. None of the demographic factors
X MkyX&y were associated with unoperated cataract in the multivariate
"v%|&@ model.
XLG6f(B= F The per cent of participants with unoperated cataract
z'iAj who said that they were dissatisfied or very dissatisfied with
<|qh5Scp Operated and unoperated cataract in Australia 79
xw1@&QwM Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
z
xe6M~+ Age group Sex Urban Rural Nursing home Weighted total
{u7%Z}<0 (years) (%) (%) (%)
a04I.5! 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
BbCt_z' Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
H2EKr#(
50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
4JOw@/nE Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
<4DSk9/ 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
kTCWyc Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
kaKV{;UM 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
Q#wl1P Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
2!UNFv#=$ 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
NTj: +z0 Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
KN41kkN 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
Muhq,>!U Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
=%wwepz6 Age-standardized
;t^8lC?>V (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)
$
N7J:Q aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
"0ITW46n their current vision was 30% (290/683), compared with 27%
)JYt zc (26/95) of participants with prior cataract surgery (chisquared,
|?a 4Nl?
1 d.f. = 0.25, P = 0.62).
#<^ngoOj Outcomes of cataract surgery
8ec6J*b Two hundred and forty-nine eyes had undergone prior
AX
{~A:B cataract surgery. Of these 249 operated eyes, 49 (20%) were
4sj:%%UE left aphakic, 6 (2.4%) had anterior chamber intraocular
=f4v: j}'| lenses and 194 (78%) had posterior chamber intraocular
pO2Y'1* lenses. The rate of capsulotomy in the eyes with intact
ZO`{t1 posterior capsules was 36% (73/202). Fifteen per cent of
.:<-E% eyes (17/114) with a clear posterior capsule had bestcorrected
4V$DV!dPQ} visual acuity of less than 6/12 compared with 43%
dWg09 sx of eyes (6/14) with opaque capsules, and 15% of eyes
3I rmDT (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
1|+Zmo" P = 0.027).
ev bqBb21b The percentage of eyes with best-corrected visual acuity
(l|:$%[0 of 6/12 or better was 96% (302/314) for eyes without
OS
X5S:XS cataract, 88% (1417/1609) for eyes with prevalent cataract
c]qq *k# and 85% (211/249) for eyes with operated cataract (chisquared,
kQr\ktN\ 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
L_3undy, operated eyes (11%) had visual acuities of less than 6/18
p6qza @ (moderate vision impairment) (Fig. 2). A cause of this
z[7j`J|Kk moderate visual impairment (but not the only cause) in four
O<@S,/Q4 (15%) eyes was secondary to cataract surgery. Three of these
Cg~GlZk} four eyes had undergone intracapsular cataract extraction
4 Ar\`{c> and the fourth eye had an opaque posterior capsule. No one
w(sD}YA) had bilateral vision impairment as a result of their cataract
1T{A(<:o$ surgery.
Bf&,ACOf DISCUSSION
7~t,Pt) To our knowledge, this is the first paper to systematically
H;QE',a9+i assess the prevalence of current cataract, previous cataract
r A/jNX@S surgery, predictors of unoperated cataract and the outcomes
Ha U6`IP of cataract surgery in a population-based sample. The Visual
s^
t1T& Impairment Project is unique in that the sampling frame and
(s/hK high response rate have ensured that the study population is
SnMHk3(\ representative of Australians aged 40 years and over. Therefore,
U!GG8;4 these data can be used to plan age-related cataract
[V\0P,l services throughout Australia.
RhJ{#G~:% We found the rate of any cataract in those over the age
RHV&m()Q of 40 years to be 22%. Although relatively high, this rate is
-y8?"WB(b significantly less than was reported in a number of previous
Cf-R?gn] studies,2,4,6 with the exception of the Casteldaccia Eye
qOyg&]7 Study.5 However, it is difficult to compare rates of cataract
aY^_+&&G between studies because of different methodologies and
;C1
]gJZ, cataract definitions employed in the various studies, as well
HG(J+ocn as the different age structures of the study populations.
AE:IXP|c Other studies have used less conservative definitions of
93zoJiLRf cataract, thus leading to higher rates of cataract as defined.
&zl=}xeA In most large epidemiologic studies of cataract, visual acuity
,tdV-9N[O has not been included in the definition of cataract.
Kh)SgJ3B@ Therefore, the prevalence of cataract may not reflect the
9{gY|2R_ actual need for cataract surgery in the community.
]!yuD/4A 80 McCarty et al.
"3kIQsD|j Table 2. Prevalence of previous cataract by age, gender and cohort
gO0X-
fN8 Age group Gender Urban Rural Nursing home Weighted total
x|#R$^4CY (years) (%) (%) (%)
jhd&\z- 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
ZK
=`Y@ Female 0.00 0.00 0.00 0.00 (
W^}fAcQKH 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
\2q!2XWgK Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
-)bi
SU, 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
<cQ)*~hN Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
#0K122oY 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
Pr
|u_^ Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
s-V5\Lip, 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
(vX+
Yw
Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
0 K
T.@P 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
W @R\m=e2 Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
jV83%%e Age-standardized
#t.)4$ (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)
7(RtPLpZ Figure 2. Visual acuity in eyes that had undergone cataract
*VJT]^_ surgery, n = 249. h, Presenting; j, best-corrected.
Up:<NHJT Operated and unoperated cataract in Australia 81
FsZW, The weighted prevalence of prior cataract surgery in the
qmNg Ez% Visual Impairment Project (3.6%) was similar to the crude
J2rw4L rate in the Beaver Dam Eye Study4 (3.1%), but less than the
tOn 6 crude rate in the Blue Mountains Eye Study6 (6.0%).
:A+nmz!z However, the age-standardized rate in the Blue Mountains
FW](GWp`: Eye Study (standardized to the age distribution of the urban
TvV_Tz4e Visual Impairment Project cohort) was found to be less than
O=2"t%Gc the Visual Impairment Project (standardized rate = 1.36%,
G/l 28yt 95% CL 1.25, 1.47). The incidence of cataract surgery in
2
~yYwX Australia has exceeded population growth.1 This is due,
: ,0F_["3 perhaps, to advances in surgical techniques and lens
R07 7eX implants that have changed the risk–benefit ratio.
K9{]v=#I The Global Initiative for the Elimination of Avoidable
,ALEfepo Blindness, sponsored by the World Health Organization,
+4 8a..4sN states that cataract surgical services should be provided that
%}T' 3 ‘have a high success rate in terms of visual outcome and
-&L(0?*qo improved quality of life’,17 although the ‘high success rate’ is
XTzz/.T;Z not defined. Population- and clinic-based studies conducted
,C4gA(')K in the United States have demonstrated marked improvement
0keqtr in visual acuity following cataract surgery.18–20 We
s&>U-7fx" found that 85% of eyes that had undergone cataract extraction
Y~FN`=O had visual acuity of 6/12 or better. Previously, we have
uT")j,tz shown that participants with prevalent cataract in this
Sbf+;:D cohort are more likely to express dissatisfaction with their
1rnbUE current vision than participants without cataract or participants
\J]qd4tF with prior cataract surgery.21 In a national study in the
17hFwo` United States, researchers found that the change in patients’
@;^7kt ratings of their vision difficulties and satisfaction with their
o@o0V vision after cataract surgery were more highly related to
`~~.0QC their change in visual functioning score than to their change
a$}n4p in visual acuity.19 Furthermore, improvement in visual function
u]<7}R@s has been shown to be associated with improvement in
(x+C=1, overall quality of life.22
Mk:k0,z A recent review found that the incidence of visually
5eP0W# significant posterior capsule opacification following
VG)Y$S8.> cataract surgery to be greater than 25%.23 We found 36%
Ym]Dlz,o capsulotomy in our population and that this was associated
)&jE<C0 with visual acuity similar to that of eyes with a clear
oB BL7/L capsule, but significantly better than that of eyes with an
<'Ppu opaque capsule.
/,tQdD& A number of studies have shown that the demand and
>Rnj6A|Q timing of cataract surgery vary according to visual acuity,
l.Psh7B2 degree of handicap and socioeconomic factors.8–10,24,25 We
yf lt2 R have also shown previously that ophthalmologists are more
O8!> t7x likely to refer a patient for cataract surgery if the patient is
Ke5fe# employed and less likely to refer a nursing home resident.7
x)^/3 In the Visual Impairment Project, we did not find that any
^GS,4[)H particular subgroup of the population was at greater risk of
=Wgz\uGJ having unoperated cataract. Universal access to health care
Vm3e6Y,K in Australia may explain the fact that people without
`S&$y4|Vs Medicare are more likely to delay cataract operations in the
@2Spfj_e USA,8 but not having private health insurance is not associated
=P,h5J with unoperated cataract in Australia.
~9tPT0^+ In summary, cataract is a significant public health problem
iJ7?6)\ in that one in four people in their 80s will have had cataract
.b3cn surgery. The importance of age-related cataract surgery will
!)nA4l=S# increase further with the ageing of the population: the
Sz"rp9x+ number of people over age 60 years is expected to double in
2V-zmyJs5 the next 20 years. Cataract surgery services are well
vv9=g*"j accessed by the Victorian population and the visual outcomes
O<:"Irq\qr of cataract surgery have been shown to be very good.
GD]yP.. These data can be used to plan for age-related cataract
McXid~ surgical services in Australia in the future as the need for
^hMJNy&R cataract extractions increases.
szDd!(&pv ACKNOWLEDGEMENTS
P:p@Iep The Visual Impairment Project was funded in part by grants
N'!: from the Victorian Health Promotion Foundation, the
9"jhS0M National Health and Medical Research Council, the Ansell
gbl`_t/ Ophthalmology Foundation, the Dorothy Edols Estate and
@77%15_Jz the Jack Brockhoff Foundation. Dr McCarty is the recipient
[VsTyqV a of a Wagstaff Fellowship in Ophthalmology from the Royal
LH"CIL2 Victorian Eye and Ear Hospital.
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