ABSTRACT
$-*!pRaVU Purpose: To quantify the prevalence of cataract, the outcomes
}:~x7|~s: of cataract surgery and the factors related to
l
c '=mA unoperated cataract in Australia.
#&7}-"Nd Methods: Participants were recruited from the Visual
Xqm::1(-( Impairment Project: a cluster, stratified sample of more than
^R@j=_8} 5000 Victorians aged 40 years and over. At examination
b 'pOJS sites interviews, clinical examinations and lens photography
qhz]Wm P were performed. Cataract was defined in participants who
smDw<slC had: had previous cataract surgery, cortical cataract greater
]]wA[c~G than 4/16, nuclear greater than Wilmer standard 2, or
5>\/[I/! posterior subcapsular greater than 1 mm2.
JC3m.)/ Results: The participant group comprised 3271 Melbourne
<z!CDg4 residents, 403 Melbourne nursing home residents and 1473
6<ZkJ:= rural residents.The weighted rate of any cataract in Victoria
aW
Y
gR was 21.5%. The overall weighted rate of prior cataract
d|yAs5@ surgery was 3.79%. Two hundred and forty-nine eyes had
CtS l had prior cataract surgery. Of these 249 procedures, 49
5)MS~ii (20%) were aphakic, 6 (2.4%) had anterior chamber
ixT:)|'i intraocular lenses and 194 (78%) had posterior chamber
XUlS\CH@{ intraocular lenses.Two hundred and eleven of these operated
U b* wuI eyes (85%) had best-corrected visual acuity of 6/12 or
|]X better, the legal requirement for a driver’s license.Twentyseven
]f({`&K5 (11%) had visual acuity of less than 6/18 (moderate
iB& 4>+N+ vision impairment). Complications of cataract surgery
x"
L20} caused reduced vision in four of the 27 eyes (15%), or 1.9%
D
'Zt of operated eyes. Three of these four eyes had undergone
ptZ <ow& intracapsular cataract extraction and the fourth eye had an
tyqT opaque posterior capsule. No one had bilateral vision
dKxyA"@ impairment as a result of cataract surgery. Surprisingly, no
bq:(u4 3 particular demographic factors (such as age, gender, rural
z3;*Em8Ir residence, occupation, employment status, health insurance
n$ou- Q status, ethnicity) were related to the presence of unoperated
S-|)QGxV6 cataract.
S_IUV) Conclusions: Although the overall prevalence of cataract is
:dQ B R quite high, no particular subgroup is systematically underserviced
mh{1*T$fP in terms of cataract surgery. Overall, the results of
<,e+
kL
{ cataract surgery are very good, with the majority of eyes
U5.LDv; achieving driving vision following cataract extraction.
0p}D(m2B Key words: cataract extraction, health planning, health
Pf\D-1gi services accessibility, prevalence
k@3Q|na INTRODUCTION
Z*= $8
e@ Cataract is the leading cause of blindness worldwide and, in
=aBctd:eX` Australia, cataract extractions account for the majority of all
t~#zMUfac ophthalmic procedures.1 Over the period 1985–94, the rate
O%5
r[ of cataract surgery in Australia was twice as high as would be
sEGO2xeI expected from the growth in the elderly population.1
hUp.tK:X7o Although there have been a number of studies reporting
[k;\S XDZo the prevalence of cataract in various populations,2–6 there is
9{5&^RbCp little information about determinants of cataract surgery in
|m^k_d!d the population. A previous survey of Australian ophthalmologists
nwF2aR
NV showed that patient concern and lifestyle, rather
=pS5uR~ than visual acuity itself, are the primary factors for referral
v{ 0= for cataract surgery.7 This supports prior research which has
lrI
S{MJ+- shown that visual acuity is not a strong predictor of need for
A|X">,A cataract surgery.8,9 Elsewhere, socioeconomic status has
yl7&5)b#9 been shown to be related to cataract surgery rates.10
d\R,Q To appropriately plan health care services, information is
CkoLTY needed about the prevalence of age-related cataract in the
ZK@N5/H( community as well as the factors associated with cataract
8TLgNQP surgery. The purpose of this study is to quantify the prevalence
CzRc%%BA of any cataract in Australia, to describe the factors
8o
'_`{ba related to unoperated cataract in the community and to
gT0BkwIV describe the visual outcomes of cataract surgery.
i*Sqd a
$ METHODS
b`~p.c%( Study population
Z7hgA-t Details about the study methodology for the Visual
XBb~\p
3y Impairment Project have been published previously.11
MHX?@.
v Briefly, cluster sampling within three strata was employed to
x7jC)M<k0 recruit subjects aged 40 years and over to participate.
YkniiB[/ Within the Melbourne Statistical Division, nine pairs of
a1+#3X. census collector districts were randomly selected. Fourteen
_m
gHJ 0v' nursing homes within a 5 km radius of these nine test sites
'rO!AcdLU were randomly chosen to recruit nursing home residents.
$RIecv<e_ Clinical and Experimental Ophthalmology (2000) 28, 77–82
@|63K)Xy Original Article
qln3 k` Operated and unoperated cataract in Australia
c#Sa]n Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
GT }F9F~ Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
E_])E`BJ n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
w$z}r Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au X(]WVCu 78 McCarty et al.
v/68*,z[ Finally, four pairs of census collector districts in four rural
h_:C+)13`x Victorian communities were randomly selected to recruit rural
Q<^Tl(`/N? residents. A household census was conducted to identify
z(_Ss@ $ eligible residents aged 40 years and over who had been a
bx{$Y_L+p resident at that address for at least 6 months. At the time of
E:JJ3X| the household census, basic information about age, sex,
=vDEfO/T country of birth, language spoken at home, education, use of
a(kg/s corrective spectacles and use of eye care services was collected.
(@<lRA
^ Eligible residents were then invited to attend a local
ysxb?6 examination site for a more detailed interview and examination.
0-HqPdjR The study protocol was approved by the Royal Victorian
n>+mL"hs Eye and Ear Hospital Human Research Ethics Committee.
\Xm,OE_v" Assessment of cataract
4zev^FR A standardized ophthalmic examination was performed after
L+Xc-uv["p pupil dilatation with one drop of 10% phenylephrine
AsAT_yv# hydrochloride. Lens opacities were graded clinically at the
ej4W{IN~: time of the examination and subsequently from photos using
l6YtEHNG the Wilmer cataract photo-grading system.12 Cortical and
cC=[Saatsf posterior subcapsular (PSC) opacities were assessed on
P
`}zlml retroillumination and measured as the proportion (in 1/16)
|Y$uqRdV of pupil circumference occupied by opacity. For this analysis,
M m[4yP% cortical cataract was defined as 4/16 or greater opacity,
Pz>s6 [ob PSC cataract was defined as opacity equal to or greater than
YQ+tDZY8` 1 mm2 and nuclear cataract was defined as opacity equal to
x_|UPF or greater than Wilmer standard 2,12 independent of visual
@.b+av4J acuity. Examples of the minimum opacities defined as cortical,
//T>G_1 nuclear and PSC cataract are presented in Figure 1.
U=DmsnD, Bilateral congenital cataracts or cataracts secondary to
J7= + intraocular inflammation or trauma were excluded from the
A?CcHw
rT analysis. Two cases of bilateral secondary cataract and eight
<,Ue
0 cases of bilateral congenital cataract were excluded from the
|uqf:V`z: analyses.
$FlW1E j A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
'MEz|Z Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
0y
7"SiFY height set to an incident angle of 30° was used for examinations.
;3d"wW]}7K Ektachrome® 200 ASA colour slide film (Eastman
i`QKH Kodak Company, Rochester, NY, USA) was used to photograph
P;P%n the nuclear opacities. The cortical opacities were
X9p.gXF photographed with an Oxford® retroillumination camera
)-0kb~;| (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
2
"Ecd film (Eastman Kodak). Photographs were graded separately
kSR\RuY* by two research assistants and discrepancies were adjudicated
xl6,s>ob by an independent reviewer. Any discrepancies
+Vm}E
0Ov between the clinical grades and the photograph grades were
tE@;X= resolved. Except in cases where photographs were missing,
A*2
bA the photograph grades were used in the analyses. Photograph
]8Q4B
W grades were available for 4301 (84%) for cortical
>#hO).`C cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
@2Z#x for PSC cataract. Cataract status was classified according to
DE%KW:Hug the severity of the opacity in the worse eye.
S/D^ Assessment of risk factors
in~D
A standardized questionnaire was used to obtain information
)3~{L;q about education, employment and ethnic background.11
1#.>a$> Specific information was elicited on the occurrence, duration
|&FkksNAl\ and treatment of a number of medical conditions,
clNkph including ocular trauma, arthritis, diabetes, gout, hypertension
*^f<W6xc and mental illness. Information about the use, dose and
'yL%3h
_@ duration of tobacco, alcohol, analgesics and steriods were
BReJ!|{m} collected, and a food frequency questionnaire was used to
h{ AII determine current consumption of dietary sources of antioxidants
2
dAB-d:k and use of vitamin supplements.
T(t+
iv Data management and statistical analysis
xL{a Data were collected either by direct computer entry with a
yp$_/p O=2 questionnaire programmed in Paradox© (Carel Corporation,
MrDc$p W G Ottawa, Canada) with internal consistency checks, or
m|{3),#V on self-coding forms. Open-ended responses were coded at
c&AygqN a later time. Data that were entered on the self-coded forms
cFeXpj?GV
were entered into a computer with double data entry and
.u4
W / reconciliation of any inconsistencies. Data range and consistency
Fxm$9(Y checks were performed on the entire data set.
CaL\fZ SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
1XD,uoxB
employed for statistical analyses.
qWODs
Ninety-five per cent confidence limits around the agespecific
;`^WGS(3.% rates were calculated according to Cochran13 to
ly:q6i account for the effect of the cluster sampling. Ninety-five
W3 'q\+ per cent confidence limits around age-standardized rates
i70wrW#k were calculated according to Breslow and Day.14 The strataspecific
1(|'WyD data were weighted according to the 1996
PK0%g$0 Australian Bureau of Statistics census data15 to reflect the
FQqI<6; cataract prevalence in the entire Victorian population.
/+@p7FqlE Univariate analyses with Student’s t-tests and chi-squared
X4 A<[&F/ tests were first employed to evaluate risk factors for unoperated
Bh;7C@dq cataract. Any factors with P < 0.10 were then fitted
UE$UR#T'w into a backwards stepwise logistic regression model. For the
cVv;Jn Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
=y0C
1LD+ final multivariate models, P < 0.05 was considered statistically
no<
^f]33 significant. Design effect was assessed through the use
|Z=^`J of cluster-specific models and multivariate models. The
.6`9H 1 design effect was assumed to be additive and an adjustment
i 7x7xtq made in the variance by adding the variance associated with
ug+io mZ the design effect prior to constructing the 95% confidence
f!!V${)X limits.
A?-oL=' RESULTS
YKO){f5 Study population
`Ye\p6v!+ A total of 3271 (83%) of the Melbourne residents, 403
<gJ
U?$ (90%) Melbourne nursing home residents, and 1473 (92%)
}j*KcB_ rural residents participated. In general, non-participants did
qoj$]
not differ from participants.16 The study population was
]3KhgK%c8 representative of the Victorian population and Australia as
S$Q8>u6Wk a whole.
eC[$B99\ The Melbourne residents ranged in age from 40 to
%we u 1f 98 years (mean = 59) and 1511 (46%) were male. The
V>A.iim Melbourne nursing home residents ranged in age from 46 to
-3;*K4z$/ 101 years (mean = 82) and 85 (21%) were men. The rural
S5G6Rj@W residents ranged in age from 40 to 103 years (mean = 60)
|aT| l^2R@ and 701 (47.5%) were men.
f"u%J/e & Prevalence of cataract and prior cataract surgery
11<KpxKpk As would be expected, the rate of any cataract increases
b+f'[; dramatically with age (Table 1). The weighted rate of any
D (h18 cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
X!m9lV< Although the rates varied somewhat between the three
DR c)iE>@ strata, they were not significantly different as the 95% confidence
($}`R
xj1@ limits overlapped. The per cent of cataractous eyes
Fl1;;F with best-corrected visual acuity of less than 6/12 was 12.5%
O }(VlR2 (65/520) for cortical cataract, 18% for nuclear cataract
F@<CsgKB- (97/534) and 14.4% (27/187) for PSC cataract. Cataract
h\P
HKC2 surgery also rose dramatically with age. The overall
br
dmz} weighted rate of prior cataract surgery in Victoria was
m"o ;L3 3.79% (95% CL 2.97, 4.60) (Table 2).
/C4^<k\ Risk factors for unoperated cataract
_ B5gR Cases of cataract that had not been removed were classified
Dg}
Ka7H as unoperated cataract. Risk factor analyses for unoperated
j&
<i& cataract were not performed with the nursing home residents
XwlbJ=mf as information about risk factor exposure was not
4( 1(e available for this cohort. The following factors were assessed
_h":> in relation to unoperated cataract: age, sex, residence
#_(jS+lP?k (urban/rural), language spoken at home (a measure of ethnic
%"af748!+D integration), country of birth, parents’ country of birth (a
T+<A`k: - measure of ethnicity), years since migration, education, use
.F(i/)vaq| of ophthalmic services, use of optometric services, private
])Qs {hs~s health insurance status, duration of distance glasses use,
"sl1vzRN glaucoma, age-related maculopathy and employment status.
bf!M#QOk? In this cross sectional study it was not possible to assess the
RhvfC5Hq level of visual acuity that would predict a patient’s having
Ie4 hhW cataract surgery, as visual acuity data prior to cataract
9>g, surgery were not available.
?zsB6B?; The significant risk factors for unoperated cataract in univariate
Jte#ZnP analyses were related to: whether a participant had
zBJ7(zh! ever seen an optometrist, seen an ophthalmologist or been
o`q_wdy? diagnosed with glaucoma; and participants’ employment
C,p
J`:P status (currently employed) and age. These significant
^+m+zd_ factors were placed in a backwards stepwise logistic regression
j~e;DO model. The factors that remained significantly related
GKFq+]W to unoperated cataract were whether participants had ever
P b]3&!a seen an ophthalmologist, seen an optometrist and been
%bD
}m! diagnosed with glaucoma. None of the demographic factors
=pznu+, were associated with unoperated cataract in the multivariate
\a=D model.
2d {y M(=( The per cent of participants with unoperated cataract
q=DN
{a: who said that they were dissatisfied or very dissatisfied with
V2<?ol Operated and unoperated cataract in Australia 79
E gDQ+(
- Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
a<A+4uXyD Age group Sex Urban Rural Nursing home Weighted total
His*t1o8'O (years) (%) (%) (%)
if]Noe 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
G_dsrpI=N Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
}irn'`I 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
5zIAhg@o:q Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
5&e<#" 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
)
9oH,gZ Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
brZ sAQ+k 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
4
8{vE3JY Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
3tmdi 3s 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
c. A|Ir Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
nWvuaQ0} 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
\G2B?>E; Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
LjH*rjS4 Age-standardized
wM_
6{ (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)
,o7hk{fR* aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
:SsUdIX;P their current vision was 30% (290/683), compared with 27%
c0Dmq)HK? (26/95) of participants with prior cataract surgery (chisquared,
&
``d 1 d.f. = 0.25, P = 0.62).
KA276# Outcomes of cataract surgery
$) 5Bf3P0 Two hundred and forty-nine eyes had undergone prior
1[*{(e cataract surgery. Of these 249 operated eyes, 49 (20%) were
R <"6ojn left aphakic, 6 (2.4%) had anterior chamber intraocular
M@thI%lR lenses and 194 (78%) had posterior chamber intraocular
=]>NDWqpHN lenses. The rate of capsulotomy in the eyes with intact
Xm4CKuU@ posterior capsules was 36% (73/202). Fifteen per cent of
%ObD2)s6:^ eyes (17/114) with a clear posterior capsule had bestcorrected
pAu72O? visual acuity of less than 6/12 compared with 43%
]p~IYNl2%j of eyes (6/14) with opaque capsules, and 15% of eyes
T|"7sPgGR (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
=_[Z W P = 0.027).
-~4+w The percentage of eyes with best-corrected visual acuity
6TH!vuQ1( of 6/12 or better was 96% (302/314) for eyes without
K"2|[ 5 cataract, 88% (1417/1609) for eyes with prevalent cataract
G]Jz"xH# and 85% (211/249) for eyes with operated cataract (chisquared,
g8'DoHJ* 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
|8)Xc=Hz operated eyes (11%) had visual acuities of less than 6/18
^\:2}4Uj_ (moderate vision impairment) (Fig. 2). A cause of this
)uLr?$qe moderate visual impairment (but not the only cause) in four
+/?iCmW (15%) eyes was secondary to cataract surgery. Three of these
n$2 RCQ four eyes had undergone intracapsular cataract extraction
:Au /2 and the fourth eye had an opaque posterior capsule. No one
s{/qS3= had bilateral vision impairment as a result of their cataract
x"(9II* surgery.
FXo2Y]K3`L DISCUSSION
9YF$CXonE= To our knowledge, this is the first paper to systematically
Icp0A\L@ assess the prevalence of current cataract, previous cataract
yoqa@ V surgery, predictors of unoperated cataract and the outcomes
Y~n`~( of cataract surgery in a population-based sample. The Visual
6(sIYZ2yq Impairment Project is unique in that the sampling frame and
THhy ~wC". high response rate have ensured that the study population is
H:a|x#" representative of Australians aged 40 years and over. Therefore,
LEh)g[
these data can be used to plan age-related cataract
nj\_lL+ services throughout Australia.
j.3o W We found the rate of any cataract in those over the age
.9LL+d of 40 years to be 22%. Although relatively high, this rate is
W'_/6_c$! significantly less than was reported in a number of previous
=:h3w#_c studies,2,4,6 with the exception of the Casteldaccia Eye
z^sST Study.5 However, it is difficult to compare rates of cataract
{TZE/A3D, between studies because of different methodologies and
Y~oT)wTU cataract definitions employed in the various studies, as well
'=} Y2?( as the different age structures of the study populations.
/~}_h O$S Other studies have used less conservative definitions of
a]1i/3/ cataract, thus leading to higher rates of cataract as defined.
2/tb6' = In most large epidemiologic studies of cataract, visual acuity
j$eCe<.3 has not been included in the definition of cataract.
|#TXE|#ux Therefore, the prevalence of cataract may not reflect the
eX<K5K.B actual need for cataract surgery in the community.
_1JmjIH)M 80 McCarty et al.
k]I*:'178 Table 2. Prevalence of previous cataract by age, gender and cohort
a@|.;#FF Age group Gender Urban Rural Nursing home Weighted total
KCXw n (years) (%) (%) (%)
R}J-nJlb 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
3t Female 0.00 0.00 0.00 0.00 (
!cCg/ 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
/!bx`cKG Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
6=>7M
b$ 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
^\YQ_/\~L Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
y<r44a_! 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
Q=.g1$LP Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
C
MqM;1 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
~'f8L#[M Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
d]k=' 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
$i&\\QNn Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
-q(:%; Age-standardized
tG 7+7Z= (95% CL) Combined 3.31 (2.70, 3.93) 4.36 (2.67, 6.06) 2.26 (0.82, 3.70) 3.79 (2.97, 4.60)
5TET<f6R Figure 2. Visual acuity in eyes that had undergone cataract
w$% BlqN surgery, n = 249. h, Presenting; j, best-corrected.
YnxU
(v'\ Operated and unoperated cataract in Australia 81
J_/05(48 The weighted prevalence of prior cataract surgery in the
N K"%DU< Visual Impairment Project (3.6%) was similar to the crude
QAXYrRu rate in the Beaver Dam Eye Study4 (3.1%), but less than the
14u^[M"U crude rate in the Blue Mountains Eye Study6 (6.0%).
5xv,!/@ However, the age-standardized rate in the Blue Mountains
tz8t9lb[ Eye Study (standardized to the age distribution of the urban
6+#,=!hF{ Visual Impairment Project cohort) was found to be less than
&O{t^D)F the Visual Impairment Project (standardized rate = 1.36%,
.ftUhg
95% CL 1.25, 1.47). The incidence of cataract surgery in
jr
dtd6b} Australia has exceeded population growth.1 This is due,
/~"AG l. perhaps, to advances in surgical techniques and lens
j~$)c)h" implants that have changed the risk–benefit ratio.
;l#?SY
Y The Global Initiative for the Elimination of Avoidable
'w`d$c/p Blindness, sponsored by the World Health Organization,
Q}ZBr^*]1e states that cataract surgical services should be provided that
(77Dif0)' ‘have a high success rate in terms of visual outcome and
(aBP|rxg improved quality of life’,17 although the ‘high success rate’ is
0Sz/c+ 6 not defined. Population- and clinic-based studies conducted
tdb4?^.s in the United States have demonstrated marked improvement
X
&09 in visual acuity following cataract surgery.18–20 We
.1%i`+uZ found that 85% of eyes that had undergone cataract extraction
/^8t'Jjd, had visual acuity of 6/12 or better. Previously, we have
0YHYx
n shown that participants with prevalent cataract in this
!zl/0o cohort are more likely to express dissatisfaction with their
rcpvH}N: current vision than participants without cataract or participants
{bxhH)a' with prior cataract surgery.21 In a national study in the
d OzO/w& United States, researchers found that the change in patients’
8Q+TE; ratings of their vision difficulties and satisfaction with their
'fXer!L} vision after cataract surgery were more highly related to
WoJ]@Me8 their change in visual functioning score than to their change
AZ}%MA;q in visual acuity.19 Furthermore, improvement in visual function
l'P[5'. has been shown to be associated with improvement in
x%ZiE5# overall quality of life.22
UYlJO{|a A recent review found that the incidence of visually
&<m
WA]cAL significant posterior capsule opacification following
I(F1S,7 cataract surgery to be greater than 25%.23 We found 36%
7?)m(CFy capsulotomy in our population and that this was associated
'[0
3L9 with visual acuity similar to that of eyes with a clear
F&-5&'6G+ capsule, but significantly better than that of eyes with an
zX006{vig opaque capsule.
!<JG&9ODP A number of studies have shown that the demand and
Q2??Kp]1 timing of cataract surgery vary according to visual acuity,
<%T%NjN
PQ degree of handicap and socioeconomic factors.8–10,24,25 We
H7 o$O have also shown previously that ophthalmologists are more
GIJV;7~ likely to refer a patient for cataract surgery if the patient is
k B$lkl\C employed and less likely to refer a nursing home resident.7
Va&KIHw In the Visual Impairment Project, we did not find that any
#nt<j2}m particular subgroup of the population was at greater risk of
e{d_p%( having unoperated cataract. Universal access to health care
1mkQ"E4 in Australia may explain the fact that people without
h=mI{w* Medicare are more likely to delay cataract operations in the
K'ed5J USA,8 but not having private health insurance is not associated
p2M?pV with unoperated cataract in Australia.
`3H?*\<( In summary, cataract is a significant public health problem
as\)S?0`. in that one in four people in their 80s will have had cataract
M<hs_8_* surgery. The importance of age-related cataract surgery will
j8F~j?%! increase further with the ageing of the population: the
ueS[sN! number of people over age 60 years is expected to double in
$A
dp the next 20 years. Cataract surgery services are well
vs)HbQ accessed by the Victorian population and the visual outcomes
Z\oAE<$ of cataract surgery have been shown to be very good.
P,LXZ These data can be used to plan for age-related cataract
8*Nt&`@ surgical services in Australia in the future as the need for
C'xU=OnA8 cataract extractions increases.
h1D~AgZOVj ACKNOWLEDGEMENTS
5Rt0h$_J The Visual Impairment Project was funded in part by grants
[0%Gu5_\ from the Victorian Health Promotion Foundation, the
3IRRFIiO National Health and Medical Research Council, the Ansell
g~WNL^GGS Ophthalmology Foundation, the Dorothy Edols Estate and
dk,
I?c& the Jack Brockhoff Foundation. Dr McCarty is the recipient
Y+Q,4s of a Wagstaff Fellowship in Ophthalmology from the Royal
:@z5& h Victorian Eye and Ear Hospital.
<o"D/<XnB3 REFERENCES
lpX p)r+ 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
|]
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