ABSTRACT
( Qw"^lE3 Purpose: To quantify the prevalence of cataract, the outcomes
b{t'Doe of cataract surgery and the factors related to
:d-+Z%Y unoperated cataract in Australia.
N$H0o+9-Y Methods: Participants were recruited from the Visual
-lm\~VZT3 Impairment Project: a cluster, stratified sample of more than
T'l >$6 5000 Victorians aged 40 years and over. At examination
n8[
sl]L sites interviews, clinical examinations and lens photography
Z*QsDS were performed. Cataract was defined in participants who
(<pc4#B@* had: had previous cataract surgery, cortical cataract greater
jyf[O - than 4/16, nuclear greater than Wilmer standard 2, or
0*q&) posterior subcapsular greater than 1 mm2.
}}v;V
*_V Results: The participant group comprised 3271 Melbourne
}Z-]m residents, 403 Melbourne nursing home residents and 1473
x(7K=K'] rural residents.The weighted rate of any cataract in Victoria
:~pPB#)nk was 21.5%. The overall weighted rate of prior cataract
7%9Sz5z surgery was 3.79%. Two hundred and forty-nine eyes had
~&=-* had prior cataract surgery. Of these 249 procedures, 49
HKCM
KHR (20%) were aphakic, 6 (2.4%) had anterior chamber
"8aw=3A intraocular lenses and 194 (78%) had posterior chamber
XS]=sfN intraocular lenses.Two hundred and eleven of these operated
e7ixi^Q eyes (85%) had best-corrected visual acuity of 6/12 or
T+m`a# better, the legal requirement for a driver’s license.Twentyseven
2Tt@2h_L (11%) had visual acuity of less than 6/18 (moderate
,Ut
p6X vision impairment). Complications of cataract surgery
.
Yg)|
/ caused reduced vision in four of the 27 eyes (15%), or 1.9%
&)O X*y of operated eyes. Three of these four eyes had undergone
`(<XdlOj intracapsular cataract extraction and the fourth eye had an
[L8Bgw1 opaque posterior capsule. No one had bilateral vision
L{;q
^ impairment as a result of cataract surgery. Surprisingly, no
BDyOX6 particular demographic factors (such as age, gender, rural
nk]jIRy^T residence, occupation, employment status, health insurance
.xuLvNyQr status, ethnicity) were related to the presence of unoperated
<P7f\$o~ cataract.
aH
e/MucK Conclusions: Although the overall prevalence of cataract is
CE:TQzg quite high, no particular subgroup is systematically underserviced
V=BF"S;-' in terms of cataract surgery. Overall, the results of
.HF+JHIUu cataract surgery are very good, with the majority of eyes
xxgS!J achieving driving vision following cataract extraction.
as-
Z)h[B Key words: cataract extraction, health planning, health
<7/ _Vs)F0 services accessibility, prevalence
1 e1$x@\\ INTRODUCTION
qi_[@da f? Cataract is the leading cause of blindness worldwide and, in
33DP0OBL^ Australia, cataract extractions account for the majority of all
6]rIYc[, ophthalmic procedures.1 Over the period 1985–94, the rate
N\1!)b of cataract surgery in Australia was twice as high as would be
[
/w{,+U expected from the growth in the elderly population.1
(m
4`l_
Although there have been a number of studies reporting
<Vm+Lt9 the prevalence of cataract in various populations,2–6 there is
tzJdUZJ little information about determinants of cataract surgery in
b"t95qlL
the population. A previous survey of Australian ophthalmologists
uuHR
! showed that patient concern and lifestyle, rather
`Lb^!6`) than visual acuity itself, are the primary factors for referral
e)LRD&Q for cataract surgery.7 This supports prior research which has
\dTX%<5D shown that visual acuity is not a strong predictor of need for
S)of.Nq.; cataract surgery.8,9 Elsewhere, socioeconomic status has
}20
Q`? been shown to be related to cataract surgery rates.10
[URo# To appropriately plan health care services, information is
mufi
>} needed about the prevalence of age-related cataract in the
:jB~rhZ~
community as well as the factors associated with cataract
j+"i$ln+s surgery. The purpose of this study is to quantify the prevalence
a,tzt
]> of any cataract in Australia, to describe the factors
&[
$qA related to unoperated cataract in the community and to
a7s+l= describe the visual outcomes of cataract surgery.
qk;*$Q METHODS
oa$-o/DhB Study population
\7rFfN3 Details about the study methodology for the Visual
16ahU$@- Impairment Project have been published previously.11
v=e`e68U~ Briefly, cluster sampling within three strata was employed to
j h0``{ recruit subjects aged 40 years and over to participate.
pQAG%i^mF Within the Melbourne Statistical Division, nine pairs of
["Mq census collector districts were randomly selected. Fourteen
Dn~r~aR$g nursing homes within a 5 km radius of these nine test sites
k=1([x were randomly chosen to recruit nursing home residents.
a3D
''Ra Clinical and Experimental Ophthalmology (2000) 28, 77–82
P,U$
X+ Original Article
DKw%z8ft| Operated and unoperated cataract in Australia
2u9O
+]EP Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
Agt6G\n Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
q-kMqnQ n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
j06?Mm_c2 Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au 7R9.g6j 78 McCarty et al.
+TzZ
Finally, four pairs of census collector districts in four rural
z{XN1'/V Victorian communities were randomly selected to recruit rural
)c|S)iJ7=z residents. A household census was conducted to identify
f}{ lRk eligible residents aged 40 years and over who had been a
/]7FX" resident at that address for at least 6 months. At the time of
Z3jh-{ 0 the household census, basic information about age, sex,
Sc!]M 5 country of birth, language spoken at home, education, use of
s+#|j;V< corrective spectacles and use of eye care services was collected.
"9F]
Wv/ Eligible residents were then invited to attend a local
VGFWF3s examination site for a more detailed interview and examination.
+LBDn"5 The study protocol was approved by the Royal Victorian
=2+';Xk\ Eye and Ear Hospital Human Research Ethics Committee.
BCnf'0q Assessment of cataract
&G63ReW7 @ A standardized ophthalmic examination was performed after
P$l-p'U- pupil dilatation with one drop of 10% phenylephrine
)gM3,gSS hydrochloride. Lens opacities were graded clinically at the
%1f, 8BM time of the examination and subsequently from photos using
w\(LG_n| the Wilmer cataract photo-grading system.12 Cortical and
+Smt8O<N posterior subcapsular (PSC) opacities were assessed on
r(UEPGu|~l retroillumination and measured as the proportion (in 1/16)
`v2]
Jk< of pupil circumference occupied by opacity. For this analysis,
~vf&JH'! cortical cataract was defined as 4/16 or greater opacity,
JiFy.Pf PSC cataract was defined as opacity equal to or greater than
1|K>V;C 1 mm2 and nuclear cataract was defined as opacity equal to
"= H.$
+ or greater than Wilmer standard 2,12 independent of visual
RX]x3- acuity. Examples of the minimum opacities defined as cortical,
q\ihye nuclear and PSC cataract are presented in Figure 1.
<9za!.(zu Bilateral congenital cataracts or cataracts secondary to
6yIl)5/= intraocular inflammation or trauma were excluded from the
n])-+[F analysis. Two cases of bilateral secondary cataract and eight
fX.V+.rj cases of bilateral congenital cataract were excluded from the
|
.bp analyses.
IKJ~sw~AQ A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
GPqF> Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
tykA69X\W height set to an incident angle of 30° was used for examinations.
^iaeY
jI Ektachrome® 200 ASA colour slide film (Eastman
OtopA) Kodak Company, Rochester, NY, USA) was used to photograph
o?G^=0T the nuclear opacities. The cortical opacities were
] o!#]] photographed with an Oxford® retroillumination camera
=hV-E
D (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
a
S-
rng film (Eastman Kodak). Photographs were graded separately
DdI7%?hK by two research assistants and discrepancies were adjudicated
V/5hEo Dt by an independent reviewer. Any discrepancies
?e|'I" between the clinical grades and the photograph grades were
k&nhF9Y4 resolved. Except in cases where photographs were missing,
Isq3YY the photograph grades were used in the analyses. Photograph
]{9oB-;, grades were available for 4301 (84%) for cortical
5H6GZ:hp cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
,5\:\e0H for PSC cataract. Cataract status was classified according to
;WIL?[;w the severity of the opacity in the worse eye.
~A0E4UJgq Assessment of risk factors
nf< <]iHf A standardized questionnaire was used to obtain information
{d$S~ about education, employment and ethnic background.11
.}fc*2.' Specific information was elicited on the occurrence, duration
H+zn:j@~L and treatment of a number of medical conditions,
6RZ[X[R[} including ocular trauma, arthritis, diabetes, gout, hypertension
#e%.z+7I and mental illness. Information about the use, dose and
OU=9fw duration of tobacco, alcohol, analgesics and steriods were
hoC}@8_ collected, and a food frequency questionnaire was used to
bcpH|}[F) determine current consumption of dietary sources of antioxidants
@{_PO{=\C and use of vitamin supplements.
\3q{E",\>@ Data management and statistical analysis
;hs:wLVa" Data were collected either by direct computer entry with a
yh_s(
>sh questionnaire programmed in Paradox© (Carel Corporation,
8O{]ML Ottawa, Canada) with internal consistency checks, or
)ymF:]QC on self-coding forms. Open-ended responses were coded at
}jU{RR%6B a later time. Data that were entered on the self-coded forms
nGW
wXySq were entered into a computer with double data entry and
oW]&]*>J reconciliation of any inconsistencies. Data range and consistency
JXj` checks were performed on the entire data set.
;_j\E(^% SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
w& RpQcV employed for statistical analyses.
+:&(Ag Ninety-five per cent confidence limits around the agespecific
`j>qOT rates were calculated according to Cochran13 to
v,>F0ofJ account for the effect of the cluster sampling. Ninety-five
{>FA ~}cX. per cent confidence limits around age-standardized rates
\g4\a?i were calculated according to Breslow and Day.14 The strataspecific
lRt8{GFy data were weighted according to the 1996
n+GC L+Mo Australian Bureau of Statistics census data15 to reflect the
%n}.E304 cataract prevalence in the entire Victorian population.
<Mc:Cg8> Univariate analyses with Student’s t-tests and chi-squared
A#1y>k tests were first employed to evaluate risk factors for unoperated
^J%
w[F
E cataract. Any factors with P < 0.10 were then fitted
wuYo@DDU# into a backwards stepwise logistic regression model. For the
cJ8*[H<NV Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
$E7yJ|p{ final multivariate models, P < 0.05 was considered statistically
r)j#Skh]. significant. Design effect was assessed through the use
G|O"Kv6 of cluster-specific models and multivariate models. The
+}+hTY$a design effect was assumed to be additive and an adjustment
[/#n+sz.A made in the variance by adding the variance associated with
609=o+ the design effect prior to constructing the 95% confidence
jilO% " limits.
;?:,L RESULTS
*Mp<4B Study population
dfJ7Dhn A total of 3271 (83%) of the Melbourne residents, 403
w@:o:yLS (90%) Melbourne nursing home residents, and 1473 (92%)
;%k%AXw rural residents participated. In general, non-participants did
NX=dx&i>+ not differ from participants.16 The study population was
~r>UjC_
B: representative of the Victorian population and Australia as
F 1zc4l6 a whole.
dJ&s/Z/>E The Melbourne residents ranged in age from 40 to
LAwS8t', 98 years (mean = 59) and 1511 (46%) were male. The
=p7W^/c Melbourne nursing home residents ranged in age from 46 to
ah<f&2f 101 years (mean = 82) and 85 (21%) were men. The rural
^y6CV4T+ residents ranged in age from 40 to 103 years (mean = 60)
:<(<tz7dj and 701 (47.5%) were men.
R;.WOies4 Prevalence of cataract and prior cataract surgery
G7=8*@q>: As would be expected, the rate of any cataract increases
$7bmUQ| dramatically with age (Table 1). The weighted rate of any
'K"*4B^3 cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
iLI]aZ Although the rates varied somewhat between the three
=~S
strata, they were not significantly different as the 95% confidence
Q$zlxn 7\ limits overlapped. The per cent of cataractous eyes
h/VYH(Tj with best-corrected visual acuity of less than 6/12 was 12.5%
1`AE] (65/520) for cortical cataract, 18% for nuclear cataract
e/3hb)#; (97/534) and 14.4% (27/187) for PSC cataract. Cataract
[*<&]^ surgery also rose dramatically with age. The overall
N} h%8\ weighted rate of prior cataract surgery in Victoria was
P3|<K-dFAK 3.79% (95% CL 2.97, 4.60) (Table 2).
fh
3
6 Risk factors for unoperated cataract
)gLasR.1 Cases of cataract that had not been removed were classified
~S6N'$
^ as unoperated cataract. Risk factor analyses for unoperated
xd.C&Dx5 cataract were not performed with the nursing home residents
U
Oo(7 as information about risk factor exposure was not
]>,|v,i
= available for this cohort. The following factors were assessed
# 0(\s@r. in relation to unoperated cataract: age, sex, residence
[)u(\nfGX (urban/rural), language spoken at home (a measure of ethnic
b#U%aPH integration), country of birth, parents’ country of birth (a
el%Qxak`" measure of ethnicity), years since migration, education, use
FHC7\#p/9Z of ophthalmic services, use of optometric services, private
]*h}sn= health insurance status, duration of distance glasses use,
[)pT{QA glaucoma, age-related maculopathy and employment status.
BSf"'0I& In this cross sectional study it was not possible to assess the
qh 3f level of visual acuity that would predict a patient’s having
jFv<]D%A[ cataract surgery, as visual acuity data prior to cataract
?0a 0 R surgery were not available.
~-%A@Lt The significant risk factors for unoperated cataract in univariate
9R[','x analyses were related to: whether a participant had
#w@Pa L iS ever seen an optometrist, seen an ophthalmologist or been
OEW,[d diagnosed with glaucoma; and participants’ employment
[
_$$P* status (currently employed) and age. These significant
TbVL71c factors were placed in a backwards stepwise logistic regression
m~eWQ_a]C@ model. The factors that remained significantly related
~B@o?8D] to unoperated cataract were whether participants had ever
-c@ 5qe> seen an ophthalmologist, seen an optometrist and been
vBx^zDe diagnosed with glaucoma. None of the demographic factors
bn35f<+ were associated with unoperated cataract in the multivariate
ZB&
Uhi model.
^nF$
<#a The per cent of participants with unoperated cataract
R-fjxM* who said that they were dissatisfied or very dissatisfied with
bicL%I2h Operated and unoperated cataract in Australia 79
{Xd5e@:Js Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
I+t38un% Age group Sex Urban Rural Nursing home Weighted total
C>dJ:.K%H (years) (%) (%) (%)
{B.]w9 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
A5ID I<a Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
MlE~gCD 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
=_J<thp Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
Y{|yB 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
2kq@*}ys Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
t|QMS M?s 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
m0\}Cc Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
|7x^@i9w 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
R} 9jgB Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
12xP)*:$ 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
0\nhg5]? Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
Sr 4 7u{n Age-standardized
'|N4fb
Zd (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)
P.Z<b:V! aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
<" l;l~Y1 their current vision was 30% (290/683), compared with 27%
72vGfT2HtZ (26/95) of participants with prior cataract surgery (chisquared,
'OW"*b 1 d.f. = 0.25, P = 0.62).
L)Ar{*xC Outcomes of cataract surgery
S_VncTIO Two hundred and forty-nine eyes had undergone prior
c$:=d4t5$ cataract surgery. Of these 249 operated eyes, 49 (20%) were
|0R%!v(, left aphakic, 6 (2.4%) had anterior chamber intraocular
Ny7=-]N4{" lenses and 194 (78%) had posterior chamber intraocular
g]
C3lf- lenses. The rate of capsulotomy in the eyes with intact
7h&`BS posterior capsules was 36% (73/202). Fifteen per cent of
E(kb!Rz eyes (17/114) with a clear posterior capsule had bestcorrected
7"NJraQ6 visual acuity of less than 6/12 compared with 43%
(DP9
& b of eyes (6/14) with opaque capsules, and 15% of eyes
KXA)i5z (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
FDs^S)B P = 0.027).
f%[ukMj& The percentage of eyes with best-corrected visual acuity
UMi`u6# of 6/12 or better was 96% (302/314) for eyes without
)u )$ `a cataract, 88% (1417/1609) for eyes with prevalent cataract
v[DbhIXU and 85% (211/249) for eyes with operated cataract (chisquared,
g74z]Uj.B 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
+y4AUU:Q
operated eyes (11%) had visual acuities of less than 6/18
Dzjt|U0ru9 (moderate vision impairment) (Fig. 2). A cause of this
-@V"i~g<e moderate visual impairment (but not the only cause) in four
)Z]y.W ) (15%) eyes was secondary to cataract surgery. Three of these
p
vQK6r four eyes had undergone intracapsular cataract extraction
ME@6.* and the fourth eye had an opaque posterior capsule. No one
:htq%gPex9 had bilateral vision impairment as a result of their cataract
J1Ki2I= surgery.
?-:: {2O) DISCUSSION
:Ip:sRz To our knowledge, this is the first paper to systematically
]F*a PV assess the prevalence of current cataract, previous cataract
1H,tP|s surgery, predictors of unoperated cataract and the outcomes
V>j hGf of cataract surgery in a population-based sample. The Visual
D
Mcxa.Sd! Impairment Project is unique in that the sampling frame and
-6~y$c&c high response rate have ensured that the study population is
uGU
v~bE representative of Australians aged 40 years and over. Therefore,
W6Aj<{\F these data can be used to plan age-related cataract
M |({
4C services throughout Australia.
g?[&0r1 We found the rate of any cataract in those over the age
z(`
}:t of 40 years to be 22%. Although relatively high, this rate is
\9(- /rE significantly less than was reported in a number of previous
2Jo~m_ studies,2,4,6 with the exception of the Casteldaccia Eye
>'}=.3\ Study.5 However, it is difficult to compare rates of cataract
A6NxM8ybn+ between studies because of different methodologies and
B&i0j5L cataract definitions employed in the various studies, as well
m
UWkb as the different age structures of the study populations.
wLOQhviI^- Other studies have used less conservative definitions of
p>:ef
<.i cataract, thus leading to higher rates of cataract as defined.
6vgBqn[ In most large epidemiologic studies of cataract, visual acuity
)v52y8G-p has not been included in the definition of cataract.
\/*Nf?; Therefore, the prevalence of cataract may not reflect the
O b8B actual need for cataract surgery in the community.
-!|WZ 80 McCarty et al.
hr[B^?6 Table 2. Prevalence of previous cataract by age, gender and cohort
',JrY) Age group Gender Urban Rural Nursing home Weighted total
Q'|0?nBOY (years) (%) (%) (%)
*!g 24 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
dCZ\ S91q
Female 0.00 0.00 0.00 0.00 (
3duG.iUlL 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
e2k4[V Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
@n7t?9Bx 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
)d +hZ' Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
W}XYmF*_? 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
gwSN>oj
& Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
?C
&x/2lt 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
K4! P' Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
4l&"]9D 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
*me,(C Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
,Z>wbMJig Age-standardized
P_p6GT:5 (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)
.3VK;au\\ Figure 2. Visual acuity in eyes that had undergone cataract
{ITv&5?> surgery, n = 249. h, Presenting; j, best-corrected.
d/XlV]#2x\ Operated and unoperated cataract in Australia 81
O)`fvpVU The weighted prevalence of prior cataract surgery in the
$]@O/[ Visual Impairment Project (3.6%) was similar to the crude
Yd'H+r5b rate in the Beaver Dam Eye Study4 (3.1%), but less than the
\\jIl3Z crude rate in the Blue Mountains Eye Study6 (6.0%).
T8n-u b< However, the age-standardized rate in the Blue Mountains
T H
|?X0b Eye Study (standardized to the age distribution of the urban
AG]WO8f) Visual Impairment Project cohort) was found to be less than
#gh
p/YoTq the Visual Impairment Project (standardized rate = 1.36%,
Ko#4z%Yq 95% CL 1.25, 1.47). The incidence of cataract surgery in
$ye^uu;
Z Australia has exceeded population growth.1 This is due,
o2DtCU-A perhaps, to advances in surgical techniques and lens
[#p&D~Du& implants that have changed the risk–benefit ratio.
ibvJWg The Global Initiative for the Elimination of Avoidable
wGPotPdE2 Blindness, sponsored by the World Health Organization,
tG/aH% 4S states that cataract surgical services should be provided that
+%P t_ ‘have a high success rate in terms of visual outcome and
m$,,YKhh improved quality of life’,17 although the ‘high success rate’ is
'9qn*H`' not defined. Population- and clinic-based studies conducted
5^yG2&># in the United States have demonstrated marked improvement
)o{VmXe@@ in visual acuity following cataract surgery.18–20 We
L?!$EPr found that 85% of eyes that had undergone cataract extraction
( :{"C6x had visual acuity of 6/12 or better. Previously, we have
c4\C[$
shown that participants with prevalent cataract in this
Jy9bY cohort are more likely to express dissatisfaction with their
l]H0g[ current vision than participants without cataract or participants
[[w2p with prior cataract surgery.21 In a national study in the
hyfR9~ United States, researchers found that the change in patients’
H)E^!eo ratings of their vision difficulties and satisfaction with their
W2`.RF^ vision after cataract surgery were more highly related to
}qAVN
their change in visual functioning score than to their change
P.cO6+jGR in visual acuity.19 Furthermore, improvement in visual function
l7z6i*R has been shown to be associated with improvement in
V5AW&kfd overall quality of life.22
fD{II+T A recent review found that the incidence of visually
]=x\b^ significant posterior capsule opacification following
4}i*cB` cataract surgery to be greater than 25%.23 We found 36%
)Vg2Jix,] capsulotomy in our population and that this was associated
2U}m RgJu with visual acuity similar to that of eyes with a clear
X D) 8? capsule, but significantly better than that of eyes with an
dAL3. % opaque capsule.
wz#A1F A number of studies have shown that the demand and
b#/i.!:a timing of cataract surgery vary according to visual acuity,
L,?/'!xV degree of handicap and socioeconomic factors.8–10,24,25 We
vZu~LW@1 have also shown previously that ophthalmologists are more
^,TTwLy-t likely to refer a patient for cataract surgery if the patient is
>&WhQhZ3kg employed and less likely to refer a nursing home resident.7
.'1SZe7O In the Visual Impairment Project, we did not find that any
wzh]97b particular subgroup of the population was at greater risk of
#r<?v
having unoperated cataract. Universal access to health care
(?3[3w~ in Australia may explain the fact that people without
)DT|(^ Medicare are more likely to delay cataract operations in the
]Bnwk
o USA,8 but not having private health insurance is not associated
)\ZzTS with unoperated cataract in Australia.
c2 *`2qK# In summary, cataract is a significant public health problem
jQ=~g-y in that one in four people in their 80s will have had cataract
\?Mf _ surgery. The importance of age-related cataract surgery will
c*;7yh&% increase further with the ageing of the population: the
lw[e*q{s. number of people over age 60 years is expected to double in
{Dr@HP/x=s the next 20 years. Cataract surgery services are well
`uo,__y accessed by the Victorian population and the visual outcomes
g5S?nHS} of cataract surgery have been shown to be very good.
T6M+|"92 These data can be used to plan for age-related cataract
rNlW7Y
surgical services in Australia in the future as the need for
VK:8 Nk_y cataract extractions increases.
syPWs57pH ACKNOWLEDGEMENTS
!bU\zH The Visual Impairment Project was funded in part by grants
c</1 from the Victorian Health Promotion Foundation, the
2c(aO[%h9 National Health and Medical Research Council, the Ansell
wRtZ`o Ophthalmology Foundation, the Dorothy Edols Estate and
k?6z_vu the Jack Brockhoff Foundation. Dr McCarty is the recipient
Paj vb-f of a Wagstaff Fellowship in Ophthalmology from the Royal
L}sx<=8.m Victorian Eye and Ear Hospital.
RJ4.
kt REFERENCES
jS<_ ) 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
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