ABSTRACT
RT4ns +J1 Purpose: To quantify the prevalence of cataract, the outcomes
RL
SP?o2J of cataract surgery and the factors related to
+t})tDPXw unoperated cataract in Australia.
k7W7S`H
Methods: Participants were recruited from the Visual
xm6cn\e Impairment Project: a cluster, stratified sample of more than
&AG,]#
5000 Victorians aged 40 years and over. At examination
#B_
``XV sites interviews, clinical examinations and lens photography
t[XxLG* were performed. Cataract was defined in participants who
ehPrxIyC had: had previous cataract surgery, cortical cataract greater
MyXgp>?~T than 4/16, nuclear greater than Wilmer standard 2, or
@or&GcQ* posterior subcapsular greater than 1 mm2.
bO^#RVH Results: The participant group comprised 3271 Melbourne
pc
J5UJY residents, 403 Melbourne nursing home residents and 1473
rfp
eX rural residents.The weighted rate of any cataract in Victoria
LkD$\i was 21.5%. The overall weighted rate of prior cataract
K1AI:$H surgery was 3.79%. Two hundred and forty-nine eyes had
al.~[T-O+ had prior cataract surgery. Of these 249 procedures, 49
Ph'*s{ (20%) were aphakic, 6 (2.4%) had anterior chamber
|$`)d87, intraocular lenses and 194 (78%) had posterior chamber
mp:%k\cF| intraocular lenses.Two hundred and eleven of these operated
Z_.Eale^ eyes (85%) had best-corrected visual acuity of 6/12 or
V\^3I7F better, the legal requirement for a driver’s license.Twentyseven
L1
1/XpR (11%) had visual acuity of less than 6/18 (moderate
p,.+i[V vision impairment). Complications of cataract surgery
;I1}
g] caused reduced vision in four of the 27 eyes (15%), or 1.9%
`j{q$Y=AG of operated eyes. Three of these four eyes had undergone
2 |
$ intracapsular cataract extraction and the fourth eye had an
i/N4uq}'A< opaque posterior capsule. No one had bilateral vision
wg\*FfQn impairment as a result of cataract surgery. Surprisingly, no
9
tvLj5~ particular demographic factors (such as age, gender, rural
TR/'L!EE residence, occupation, employment status, health insurance
484lB}H status, ethnicity) were related to the presence of unoperated
!*_5 B' cataract.
Bt[OGa(q Conclusions: Although the overall prevalence of cataract is
d~1Nct$: quite high, no particular subgroup is systematically underserviced
{_ti*# in terms of cataract surgery. Overall, the results of
0vbiq cataract surgery are very good, with the majority of eyes
/R7qR# achieving driving vision following cataract extraction.
Xo]QV.n Key words: cataract extraction, health planning, health
5|&8MGW-$ services accessibility, prevalence
H7bdL 8/ INTRODUCTION
H-$ )@ Cataract is the leading cause of blindness worldwide and, in
Cg[]y1Ne Australia, cataract extractions account for the majority of all
`oQ)qa_ ophthalmic procedures.1 Over the period 1985–94, the rate
q{I,i(%m8 of cataract surgery in Australia was twice as high as would be
jkw:h0hX expected from the growth in the elderly population.1
<Hw)},_* Although there have been a number of studies reporting
'wB6- the prevalence of cataract in various populations,2–6 there is
k9H7(nS{ little information about determinants of cataract surgery in
0?59o!@h the population. A previous survey of Australian ophthalmologists
/Ud<4j- showed that patient concern and lifestyle, rather
a-w=Lp
VM than visual acuity itself, are the primary factors for referral
&iCE/ for cataract surgery.7 This supports prior research which has
o;bK 7D shown that visual acuity is not a strong predictor of need for
DrE
+{Spm cataract surgery.8,9 Elsewhere, socioeconomic status has
*c'nPa$+|S been shown to be related to cataract surgery rates.10
S0?4}7`A To appropriately plan health care services, information is
\7M+0Ul1 needed about the prevalence of age-related cataract in the
*{/
ww9fT community as well as the factors associated with cataract
y+D 3(Bsn surgery. The purpose of this study is to quantify the prevalence
V?"X0>]0 of any cataract in Australia, to describe the factors
,'[&" Eg related to unoperated cataract in the community and to
>'IFr9&3 describe the visual outcomes of cataract surgery.
ds@X%L;_ METHODS
zs#s"e:jeR Study population
90JD`Nz Details about the study methodology for the Visual
Fe8JsB- Impairment Project have been published previously.11
a(}dF?M= Briefly, cluster sampling within three strata was employed to
%JmRJpCvR recruit subjects aged 40 years and over to participate.
ShXk\" Within the Melbourne Statistical Division, nine pairs of
u{Jv6K, census collector districts were randomly selected. Fourteen
&' ,A2iG nursing homes within a 5 km radius of these nine test sites
!]c]:ed\C were randomly chosen to recruit nursing home residents.
0Y rdu,c Clinical and Experimental Ophthalmology (2000) 28, 77–82
.yz-o\,gF% Original Article
Ki#({~ Operated and unoperated cataract in Australia
4R_Vi[
i Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
[$; \1P/ Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
Q y(Gy'q~ n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
>7@kwj-f) Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au ?39B(T 78 McCarty et al.
7U=|>)Q0s Finally, four pairs of census collector districts in four rural
Y|ONCc Victorian communities were randomly selected to recruit rural
BR8W8nRb residents. A household census was conducted to identify
x!\FB.h4!( eligible residents aged 40 years and over who had been a
J?/.|Y]e resident at that address for at least 6 months. At the time of
vCC}IDd the household census, basic information about age, sex,
c&zZsJ"~ country of birth, language spoken at home, education, use of
"=~P&Mi_ corrective spectacles and use of eye care services was collected.
Vp3
9`m-W Eligible residents were then invited to attend a local
e_C9VNP examination site for a more detailed interview and examination.
F
8 *e The study protocol was approved by the Royal Victorian
bkmW[w:M Eye and Ear Hospital Human Research Ethics Committee.
-w41Bvz0 Assessment of cataract
Y-(),k_Q: A standardized ophthalmic examination was performed after
sA18f2 pupil dilatation with one drop of 10% phenylephrine
Zf~
[4Eeb hydrochloride. Lens opacities were graded clinically at the
]:* 8
Mb# time of the examination and subsequently from photos using
AF{k^^|H the Wilmer cataract photo-grading system.12 Cortical and
1](5wK-Z posterior subcapsular (PSC) opacities were assessed on
bS
'a ) retroillumination and measured as the proportion (in 1/16)
u7|{~D&f of pupil circumference occupied by opacity. For this analysis,
y^; =+Z cortical cataract was defined as 4/16 or greater opacity,
j7;v'eA`;7 PSC cataract was defined as opacity equal to or greater than
f.Y9gkt3d 1 mm2 and nuclear cataract was defined as opacity equal to
&y1' J or greater than Wilmer standard 2,12 independent of visual
oOk.Fq acuity. Examples of the minimum opacities defined as cortical,
\Cx)
~bq< nuclear and PSC cataract are presented in Figure 1.
W(*:8}m,p Bilateral congenital cataracts or cataracts secondary to
7e&R6j intraocular inflammation or trauma were excluded from the
o{*8l#x8 analysis. Two cases of bilateral secondary cataract and eight
T:0X-U cases of bilateral congenital cataract were excluded from the
m{={a5GD analyses.
1E Lzzn A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
6y)xMX Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
S~vb
ISl height set to an incident angle of 30° was used for examinations.
lo:]r.lX{ Ektachrome® 200 ASA colour slide film (Eastman
qs6yEuh# Kodak Company, Rochester, NY, USA) was used to photograph
z602(mxGg the nuclear opacities. The cortical opacities were
cL*D_)?8 photographed with an Oxford® retroillumination camera
6w K= (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
GCrh4rxgg film (Eastman Kodak). Photographs were graded separately
9bjjo;A by two research assistants and discrepancies were adjudicated
3+m#v8h1 by an independent reviewer. Any discrepancies
rWbu
oG+8 between the clinical grades and the photograph grades were
Oa~t&s resolved. Except in cases where photographs were missing,
%"
$.2O@ the photograph grades were used in the analyses. Photograph
w5jH#ja grades were available for 4301 (84%) for cortical
zdn e2 cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
xc R for PSC cataract. Cataract status was classified according to
zsI0Q47\ the severity of the opacity in the worse eye.
9A\J*OU Assessment of risk factors
lfu1
PCe5 A standardized questionnaire was used to obtain information
/-4i"| about education, employment and ethnic background.11
;^:~xJFx| Specific information was elicited on the occurrence, duration
+IVVsVp and treatment of a number of medical conditions,
N##T1 Qm) including ocular trauma, arthritis, diabetes, gout, hypertension
ksY^w+>(! and mental illness. Information about the use, dose and
qsFA~{o. duration of tobacco, alcohol, analgesics and steriods were
XPzwT2_E collected, and a food frequency questionnaire was used to
HeGGAjc determine current consumption of dietary sources of antioxidants
>;o^qi_$ and use of vitamin supplements.
[
x!T<jJ Data management and statistical analysis
.EH^1.|v Data were collected either by direct computer entry with a
X =S;8=N questionnaire programmed in Paradox© (Carel Corporation,
{exF"ap Ottawa, Canada) with internal consistency checks, or
9R>A,x( on self-coding forms. Open-ended responses were coded at
i1vBg}WHN a later time. Data that were entered on the self-coded forms
QfU
0*W?r were entered into a computer with double data entry and
8c+i+gp! reconciliation of any inconsistencies. Data range and consistency
@Qruc\_ checks were performed on the entire data set.
ezwcOYMXK SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
FlVGi3 employed for statistical analyses.
S_
c#{4n Ninety-five per cent confidence limits around the agespecific
,Q(n(m' rates were calculated according to Cochran13 to
('
`) m account for the effect of the cluster sampling. Ninety-five
kp<9o!?) per cent confidence limits around age-standardized rates
HtY\!_Ea were calculated according to Breslow and Day.14 The strataspecific
)^%,\l-! data were weighted according to the 1996
} M'\s Australian Bureau of Statistics census data15 to reflect the
k>VP<Zm13 cataract prevalence in the entire Victorian population.
CNbrXN Univariate analyses with Student’s t-tests and chi-squared
P;hjr;
tests were first employed to evaluate risk factors for unoperated
_sZ/tU@_-K cataract. Any factors with P < 0.10 were then fitted
HW.S~eLw* into a backwards stepwise logistic regression model. For the
56?U4wj7{ Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
8Mws?]\/q final multivariate models, P < 0.05 was considered statistically
aeSy,: significant. Design effect was assessed through the use
]3
0
7. of cluster-specific models and multivariate models. The
J_rCo4} design effect was assumed to be additive and an adjustment
* +A!12s@ made in the variance by adding the variance associated with
?H*_:?=6 the design effect prior to constructing the 95% confidence
8qS)j1.! limits.
( Y/
DMQ RESULTS
>Cd%tIie* Study population
u#J5M A total of 3271 (83%) of the Melbourne residents, 403
PJkMn (90%) Melbourne nursing home residents, and 1473 (92%)
6mRvuJ% rural residents participated. In general, non-participants did
;HqK^[1\ not differ from participants.16 The study population was
.V/TVz!b representative of the Victorian population and Australia as
K3
]hUe
# a whole.
I
&{dan2 The Melbourne residents ranged in age from 40 to
5^*
d4[&+ 98 years (mean = 59) and 1511 (46%) were male. The
C8&)-v| Melbourne nursing home residents ranged in age from 46 to
|":^3 101 years (mean = 82) and 85 (21%) were men. The rural
7;|6g8= residents ranged in age from 40 to 103 years (mean = 60)
cE]tvL:g and 701 (47.5%) were men.
{_(;&\5 Prevalence of cataract and prior cataract surgery
$:
Qi9N As would be expected, the rate of any cataract increases
.P ,\69g~A dramatically with age (Table 1). The weighted rate of any
xZ,g6s2o cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
lfj>]om$ Although the rates varied somewhat between the three
]4z?sk@ strata, they were not significantly different as the 95% confidence
5[/*UtB
limits overlapped. The per cent of cataractous eyes
<7TpC@"/g with best-corrected visual acuity of less than 6/12 was 12.5%
<'GI<Hc (65/520) for cortical cataract, 18% for nuclear cataract
CH9#<?l (97/534) and 14.4% (27/187) for PSC cataract. Cataract
|n6nRE wW surgery also rose dramatically with age. The overall
ND21; weighted rate of prior cataract surgery in Victoria was
vkBngsS 3.79% (95% CL 2.97, 4.60) (Table 2).
YJ!6)d?C. Risk factors for unoperated cataract
cm7aL%D$c Cases of cataract that had not been removed were classified
^$x^JM ]/ as unoperated cataract. Risk factor analyses for unoperated
IS'=%qhC` cataract were not performed with the nursing home residents
8Cm^#S,+ as information about risk factor exposure was not
%
;6e@U} available for this cohort. The following factors were assessed
9IIe: in relation to unoperated cataract: age, sex, residence
TR:D (urban/rural), language spoken at home (a measure of ethnic
},[j+wx integration), country of birth, parents’ country of birth (a
@~a52'\ measure of ethnicity), years since migration, education, use
J@yy2AZnO of ophthalmic services, use of optometric services, private
=|?w<qc health insurance status, duration of distance glasses use,
ADHe![6q glaucoma, age-related maculopathy and employment status.
^(&:=r.PC In this cross sectional study it was not possible to assess the
g<{~f level of visual acuity that would predict a patient’s having
pK$^@~DE cataract surgery, as visual acuity data prior to cataract
OwDjUKeN surgery were not available.
$9ON3> The significant risk factors for unoperated cataract in univariate
nTYqZlI, analyses were related to: whether a participant had
R8HA X ever seen an optometrist, seen an ophthalmologist or been
+F67g00T| diagnosed with glaucoma; and participants’ employment
P^1rNB status (currently employed) and age. These significant
`CHgTkv factors were placed in a backwards stepwise logistic regression
Gm.v-T$ model. The factors that remained significantly related
N
4,w to unoperated cataract were whether participants had ever
f Z \Ev%F seen an ophthalmologist, seen an optometrist and been
R$w=+%F diagnosed with glaucoma. None of the demographic factors
rtUdL,Hx were associated with unoperated cataract in the multivariate
EzthRe9 model.
tpCEWdn5 The per cent of participants with unoperated cataract
sY1*WolA who said that they were dissatisfied or very dissatisfied with
uswz@
[pa Operated and unoperated cataract in Australia 79
wePMBL1P* Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
b!UT<:o Age group Sex Urban Rural Nursing home Weighted total
Dcp,9"yt% (years) (%) (%) (%)
n287@Y4Ru 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
~[,E
i k Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
-8TJ~t%w4 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
'9RHwKu&s Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
5a_K|(~3I 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
NP|U
|zn Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
c{&sf
y 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
h3JIiwv0! Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
[9$>N 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
i>0bI^H Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
cIq3En 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
Ak4iG2 Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
_<5>
E Age-standardized
2#|Q=rWB (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)
)~!Gs/w6 aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
qt3
\*U7x their current vision was 30% (290/683), compared with 27%
WRD^S:`BH (26/95) of participants with prior cataract surgery (chisquared,
Ba@UX(t 1 d.f. = 0.25, P = 0.62).
"$m3xO Outcomes of cataract surgery
F1MPo;e Two hundred and forty-nine eyes had undergone prior
iUSs) []H> cataract surgery. Of these 249 operated eyes, 49 (20%) were
hX[hR left aphakic, 6 (2.4%) had anterior chamber intraocular
3B;B#0g50 lenses and 194 (78%) had posterior chamber intraocular
`bivAL lenses. The rate of capsulotomy in the eyes with intact
c)lM
i}/ posterior capsules was 36% (73/202). Fifteen per cent of
Tw|=;m eyes (17/114) with a clear posterior capsule had bestcorrected
CQ13fu+|6 visual acuity of less than 6/12 compared with 43%
{OB\~$TH of eyes (6/14) with opaque capsules, and 15% of eyes
t0hg!_$bq (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
M|76,2u P = 0.027).
@'~v~3
$S The percentage of eyes with best-corrected visual acuity
6i>xCb of 6/12 or better was 96% (302/314) for eyes without
n?:s
/6tP cataract, 88% (1417/1609) for eyes with prevalent cataract
.PxtcC.K and 85% (211/249) for eyes with operated cataract (chisquared,
|?{Zx&yUw 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
1oodw!h
W operated eyes (11%) had visual acuities of less than 6/18
s{hJ"lv: (moderate vision impairment) (Fig. 2). A cause of this
U%U%a,rA5s moderate visual impairment (but not the only cause) in four
Z\`uI+` (15%) eyes was secondary to cataract surgery. Three of these
%'@&j2j> four eyes had undergone intracapsular cataract extraction
3X%>xUI and the fourth eye had an opaque posterior capsule. No one
aq[kKS` had bilateral vision impairment as a result of their cataract
\>M3E surgery.
6fQQKM@a| DISCUSSION
W
aks*^| To our knowledge, this is the first paper to systematically
9?@M Zh assess the prevalence of current cataract, previous cataract
zjB8~ku# surgery, predictors of unoperated cataract and the outcomes
:\gdQG of cataract surgery in a population-based sample. The Visual
dsrzXmE0 Impairment Project is unique in that the sampling frame and
</Q<*@p? high response rate have ensured that the study population is
zTm&m#){3A representative of Australians aged 40 years and over. Therefore,
s$|
GVv1B these data can be used to plan age-related cataract
AfFFu\ services throughout Australia.
YG!~v~sV We found the rate of any cataract in those over the age
S'vrO}yU of 40 years to be 22%. Although relatively high, this rate is
^Jsx^? significantly less than was reported in a number of previous
y
kwS-e studies,2,4,6 with the exception of the Casteldaccia Eye
G-9]z[\# Study.5 However, it is difficult to compare rates of cataract
Pr<.ld\ between studies because of different methodologies and
-7$7TD`'7 cataract definitions employed in the various studies, as well
~Wf&$p<| as the different age structures of the study populations.
" :@5|4qK Other studies have used less conservative definitions of
7 S(5\9 cataract, thus leading to higher rates of cataract as defined.
H?m9HBDpn In most large epidemiologic studies of cataract, visual acuity
Akb#1Ww4 has not been included in the definition of cataract.
f]jAa?d T& Therefore, the prevalence of cataract may not reflect the
Oc}4`?oy<O actual need for cataract surgery in the community.
j;WZ[g#t 80 McCarty et al.
LK-2e$1 Table 2. Prevalence of previous cataract by age, gender and cohort
-iLp3m<ai Age group Gender Urban Rural Nursing home Weighted total
fb0i6RC~& (years) (%) (%) (%)
S|CN)8Jsi 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
AvfSR p Female 0.00 0.00 0.00 0.00 (
eG55[V<! 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
R7+3$F5B Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
r#M0X^4A 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
8E`A`z Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
IH(]RHTp% 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
V+G.
TI
P Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
,UNCBnv1 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
E4idEQ}H Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
[Q9#44@{S; 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
_Vul9= Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
9ozN$: Age-standardized
)(V|d$n (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)
b9`vYnLk Figure 2. Visual acuity in eyes that had undergone cataract
Q"rQVO surgery, n = 249. h, Presenting; j, best-corrected.
`>'%!E9G Operated and unoperated cataract in Australia 81
4}-{sS}MP The weighted prevalence of prior cataract surgery in the
jiw5>RNt Visual Impairment Project (3.6%) was similar to the crude
Z'=:Bo{ rate in the Beaver Dam Eye Study4 (3.1%), but less than the
b`:n i
crude rate in the Blue Mountains Eye Study6 (6.0%).
e x"E50 However, the age-standardized rate in the Blue Mountains
IP<]a5 Eye Study (standardized to the age distribution of the urban
R2K{vs Visual Impairment Project cohort) was found to be less than
5AFy6Ab the Visual Impairment Project (standardized rate = 1.36%,
re}_+svU 95% CL 1.25, 1.47). The incidence of cataract surgery in
8);G'7O Australia has exceeded population growth.1 This is due,
'Z;8-1M?O perhaps, to advances in surgical techniques and lens
%#
M=qP implants that have changed the risk–benefit ratio.
%BBM
%Lj The Global Initiative for the Elimination of Avoidable
VDy2!0 Blindness, sponsored by the World Health Organization,
TjDDvXY states that cataract surgical services should be provided that
}(MI}o} ‘have a high success rate in terms of visual outcome and
5ub|r0&M improved quality of life’,17 although the ‘high success rate’ is
%)o'9 not defined. Population- and clinic-based studies conducted
YL[n85l>1 in the United States have demonstrated marked improvement
D_s0)|j$cy in visual acuity following cataract surgery.18–20 We
kfc5ra>& found that 85% of eyes that had undergone cataract extraction
,ICn]P
dz@ had visual acuity of 6/12 or better. Previously, we have
*h([ai"1- shown that participants with prevalent cataract in this
|J:|56kVZq cohort are more likely to express dissatisfaction with their
rm}%C(C{J current vision than participants without cataract or participants
!{S& " with prior cataract surgery.21 In a national study in the
b aO^Z
United States, researchers found that the change in patients’
.Tm m ratings of their vision difficulties and satisfaction with their
Nv[MU@Tv vision after cataract surgery were more highly related to
NP#6'eH\ their change in visual functioning score than to their change
#OMFv. in visual acuity.19 Furthermore, improvement in visual function
-|.Izgc has been shown to be associated with improvement in
Ga$ J7R overall quality of life.22
ojva~mnFf A recent review found that the incidence of visually
ko-,l6E significant posterior capsule opacification following
B=d
:r cataract surgery to be greater than 25%.23 We found 36%
qdCcMcGt capsulotomy in our population and that this was associated
QKB*N)%6 with visual acuity similar to that of eyes with a clear
KkJrh@lk capsule, but significantly better than that of eyes with an
'$q=r x opaque capsule.
~[@gu,Wb A number of studies have shown that the demand and
]I
^b&N timing of cataract surgery vary according to visual acuity,
4roqD;5|~| degree of handicap and socioeconomic factors.8–10,24,25 We
qP k`e}D have also shown previously that ophthalmologists are more
)Vf!U
" likely to refer a patient for cataract surgery if the patient is
Y
n7z#bu employed and less likely to refer a nursing home resident.7
V1-URC24vd In the Visual Impairment Project, we did not find that any
+Y!
P VMF particular subgroup of the population was at greater risk of
UTS.o#d having unoperated cataract. Universal access to health care
E#zLm in Australia may explain the fact that people without
FGey%:p9$ Medicare are more likely to delay cataract operations in the
GoUsB|-\ USA,8 but not having private health insurance is not associated
t9eEcqMg with unoperated cataract in Australia.
;O~k{5.iS In summary, cataract is a significant public health problem
2
r';)8: in that one in four people in their 80s will have had cataract
UP .4# 1I
surgery. The importance of age-related cataract surgery will
IY"+hHt increase further with the ageing of the population: the
`UD,ne number of people over age 60 years is expected to double in
/g)( the next 20 years. Cataract surgery services are well
,CxIA^ accessed by the Victorian population and the visual outcomes
IgyoBfj\d of cataract surgery have been shown to be very good.
PJF1+I.%c# These data can be used to plan for age-related cataract
q@&6&cd surgical services in Australia in the future as the need for
91\Sb:> cataract extractions increases.
Whl^~$+f ACKNOWLEDGEMENTS
SVn $!t The Visual Impairment Project was funded in part by grants
,<s
/K from the Victorian Health Promotion Foundation, the
:|a$[g5
National Health and Medical Research Council, the Ansell
S;^'Ek"Z. Ophthalmology Foundation, the Dorothy Edols Estate and
mFrDV,V the Jack Brockhoff Foundation. Dr McCarty is the recipient
D k<NlH zp of a Wagstaff Fellowship in Ophthalmology from the Royal
rrP_7D Victorian Eye and Ear Hospital.
ZJ8"5RW REFERENCES
nrV!<nNBk 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
Oq*;GR(Q Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
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