ABSTRACT
|))O3]- Purpose: To quantify the prevalence of cataract, the outcomes
vhd +A of cataract surgery and the factors related to
eufGU)M unoperated cataract in Australia.
<44A*ux Methods: Participants were recruited from the Visual
@8eQ|.q]Q Impairment Project: a cluster, stratified sample of more than
N%Uk/ c' 5000 Victorians aged 40 years and over. At examination
y
Q-{
CJ, sites interviews, clinical examinations and lens photography
\'CA:9V} were performed. Cataract was defined in participants who
.D{He9 had: had previous cataract surgery, cortical cataract greater
EECuJ+T than 4/16, nuclear greater than Wilmer standard 2, or
M2!2J posterior subcapsular greater than 1 mm2.
4Kh0evZ Results: The participant group comprised 3271 Melbourne
N~|Z@pU" residents, 403 Melbourne nursing home residents and 1473
s8.SEk|pB rural residents.The weighted rate of any cataract in Victoria
4l'`q+^- was 21.5%. The overall weighted rate of prior cataract
W9!K~g_ surgery was 3.79%. Two hundred and forty-nine eyes had
ib- H
jJ8 had prior cataract surgery. Of these 249 procedures, 49
W2BZG(dm (20%) were aphakic, 6 (2.4%) had anterior chamber
4o|<zn intraocular lenses and 194 (78%) had posterior chamber
8(>2+#exw intraocular lenses.Two hundred and eleven of these operated
)F_nK f"a eyes (85%) had best-corrected visual acuity of 6/12 or
&4{!5r better, the legal requirement for a driver’s license.Twentyseven
z\`tnz7>$ (11%) had visual acuity of less than 6/18 (moderate
n7/>+V+ vision impairment). Complications of cataract surgery
k}0b7er=R caused reduced vision in four of the 27 eyes (15%), or 1.9%
xmi@
XL@t of operated eyes. Three of these four eyes had undergone
Mp?L9 intracapsular cataract extraction and the fourth eye had an
+_1sFH` opaque posterior capsule. No one had bilateral vision
>%H(0G#X impairment as a result of cataract surgery. Surprisingly, no
/B<QYvv particular demographic factors (such as age, gender, rural
m "96%sB residence, occupation, employment status, health insurance
?$#P
=VK status, ethnicity) were related to the presence of unoperated
8j)*T9 cataract.
$!$,cKPl5 Conclusions: Although the overall prevalence of cataract is
a}Z+"D quite high, no particular subgroup is systematically underserviced
*yv@B!r in terms of cataract surgery. Overall, the results of
jG{OLF6 ! cataract surgery are very good, with the majority of eyes
bTt1y O achieving driving vision following cataract extraction.
Ab6R ?mUM Key words: cataract extraction, health planning, health
55FRPNx-x services accessibility, prevalence
l b;P&V
INTRODUCTION
;
!A=YXB Cataract is the leading cause of blindness worldwide and, in
On|b- Australia, cataract extractions account for the majority of all
c \;_jg ophthalmic procedures.1 Over the period 1985–94, the rate
5
^K\<+{~B of cataract surgery in Australia was twice as high as would be
oL~?^`cGZ expected from the growth in the elderly population.1
5> lIrBf Although there have been a number of studies reporting
0xY</S the prevalence of cataract in various populations,2–6 there is
KP&xk13) little information about determinants of cataract surgery in
L5'?.9] the population. A previous survey of Australian ophthalmologists
O?O=]s
u showed that patient concern and lifestyle, rather
d<6m_!L than visual acuity itself, are the primary factors for referral
IdM~'
Q>\ for cataract surgery.7 This supports prior research which has
jweX"G54R shown that visual acuity is not a strong predictor of need for
c8T| o=`k6 cataract surgery.8,9 Elsewhere, socioeconomic status has
&%%ix#iF been shown to be related to cataract surgery rates.10
"8"aYD_ To appropriately plan health care services, information is
A'.=SA2.Y needed about the prevalence of age-related cataract in the
[N12X7O3 community as well as the factors associated with cataract
PQp =bX, surgery. The purpose of this study is to quantify the prevalence
3=yfbO<
- of any cataract in Australia, to describe the factors
b;%t*?t related to unoperated cataract in the community and to
>ZW|wpO describe the visual outcomes of cataract surgery.
4Us_Z{. METHODS
Lx tgf2r Study population
lB0`|UEb ( Details about the study methodology for the Visual
~d].<Be Impairment Project have been published previously.11
tJ
2GSZ` Briefly, cluster sampling within three strata was employed to
tbWfm5
$ recruit subjects aged 40 years and over to participate.
Ij$C@hH Within the Melbourne Statistical Division, nine pairs of
!LzA census collector districts were randomly selected. Fourteen
6T4I,XrY_F nursing homes within a 5 km radius of these nine test sites
UoPY:(?;i were randomly chosen to recruit nursing home residents.
9Msy=qvYG Clinical and Experimental Ophthalmology (2000) 28, 77–82
&!OEd] Original Article
,2^4"gIl Operated and unoperated cataract in Australia
+[<YE Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
o8Gygi5 Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
Pc_aEBq n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
'3Lu_]I- Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au m3TR}=n 78 McCarty et al.
:
nQlS Finally, four pairs of census collector districts in four rural
|1RVm?~i Victorian communities were randomly selected to recruit rural
Ps74SoD- residents. A household census was conducted to identify
xC,x_:R` eligible residents aged 40 years and over who had been a
Dlq!:dF{& resident at that address for at least 6 months. At the time of
3iIy_nWC the household census, basic information about age, sex,
Aeb(b+=
country of birth, language spoken at home, education, use of
b:D92pH corrective spectacles and use of eye care services was collected.
v6s,lC5qR Eligible residents were then invited to attend a local
V`1,s~"q examination site for a more detailed interview and examination.
TK
fN`6 The study protocol was approved by the Royal Victorian
})H d]a Eye and Ear Hospital Human Research Ethics Committee.
3o%vV* Assessment of cataract
pA6KiY& A standardized ophthalmic examination was performed after
yQE'
!m pupil dilatation with one drop of 10% phenylephrine
R7kkth hydrochloride. Lens opacities were graded clinically at the
y
%Q. ( time of the examination and subsequently from photos using
_cX}!d!j the Wilmer cataract photo-grading system.12 Cortical and
f9W:-00QD posterior subcapsular (PSC) opacities were assessed on
Q$c6l[(g retroillumination and measured as the proportion (in 1/16)
e
@Lxduq of pupil circumference occupied by opacity. For this analysis,
z# ^fS
| cortical cataract was defined as 4/16 or greater opacity,
c3^!S0U PSC cataract was defined as opacity equal to or greater than
Lwr's'ao. 1 mm2 and nuclear cataract was defined as opacity equal to
u]P| or greater than Wilmer standard 2,12 independent of visual
`m
7<_#Y acuity. Examples of the minimum opacities defined as cortical,
%.Ma_4o
Z nuclear and PSC cataract are presented in Figure 1.
rD].=.?1 Bilateral congenital cataracts or cataracts secondary to
SM2Lbf
p!u intraocular inflammation or trauma were excluded from the
Io1j%T#ZT analysis. Two cases of bilateral secondary cataract and eight
5#,H&ui\ cases of bilateral congenital cataract were excluded from the
*an
Ng<@ analyses.
jk9f{Iu A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
{^WK#$] Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
;xZ+1zmL0 height set to an incident angle of 30° was used for examinations.
9D T< Ektachrome® 200 ASA colour slide film (Eastman
jE\G_> Kodak Company, Rochester, NY, USA) was used to photograph
c*;oR$VW the nuclear opacities. The cortical opacities were
r5}p . photographed with an Oxford® retroillumination camera
rwRZGd *p (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
--K)7 film (Eastman Kodak). Photographs were graded separately
IT| h;NUG by two research assistants and discrepancies were adjudicated
h>/teHy / by an independent reviewer. Any discrepancies
A2|Bbqd between the clinical grades and the photograph grades were
b`jR("U resolved. Except in cases where photographs were missing,
g3:@90Ba the photograph grades were used in the analyses. Photograph
;6G]~}>o grades were available for 4301 (84%) for cortical
UP-eKK'z cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
.U!EA0B for PSC cataract. Cataract status was classified according to
\p4*Q}t the severity of the opacity in the worse eye.
dn(!wC] Assessment of risk factors
zg2d}"dV A standardized questionnaire was used to obtain information
oGcgd$%ZB about education, employment and ethnic background.11
Y&
6jFT_ Specific information was elicited on the occurrence, duration
|! 9~ and treatment of a number of medical conditions,
uw+nll*W% including ocular trauma, arthritis, diabetes, gout, hypertension
#{6VdWZ and mental illness. Information about the use, dose and
F*k
=JL duration of tobacco, alcohol, analgesics and steriods were
F5*-HR collected, and a food frequency questionnaire was used to
vMzL+D2) determine current consumption of dietary sources of antioxidants
#Pd9i5~N and use of vitamin supplements.
`oxBIn*BD Data management and statistical analysis
o,i_py Data were collected either by direct computer entry with a
OX;bA^+}P questionnaire programmed in Paradox© (Carel Corporation,
D$FTnY Ottawa, Canada) with internal consistency checks, or
i+`8$uz on self-coding forms. Open-ended responses were coded at
Ftyxz&-4$p a later time. Data that were entered on the self-coded forms
lMgguu~qg were entered into a computer with double data entry and
!XTzsN reconciliation of any inconsistencies. Data range and consistency
@1j*\gYz checks were performed on the entire data set.
(#dR\Di SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
nAQ[
-NbW, employed for statistical analyses.
/[/L%;a'p Ninety-five per cent confidence limits around the agespecific
|;J`~H"K rates were calculated according to Cochran13 to
ndQw>
account for the effect of the cluster sampling. Ninety-five
Y$OE[nGi%X per cent confidence limits around age-standardized rates
*L<EGFP were calculated according to Breslow and Day.14 The strataspecific
Ja1 `S+ data were weighted according to the 1996
^qL<=UC. Australian Bureau of Statistics census data15 to reflect the
+=W(c8~P cataract prevalence in the entire Victorian population.
>_Tyzl>z Univariate analyses with Student’s t-tests and chi-squared
@Mya|zb
tests were first employed to evaluate risk factors for unoperated
LDegJer-v cataract. Any factors with P < 0.10 were then fitted
[Vbdsu9 into a backwards stepwise logistic regression model. For the
b0}dy\dnQ Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
RSAGSGp final multivariate models, P < 0.05 was considered statistically
/\,3AInLb significant. Design effect was assessed through the use
hvI#D>Z!Yp of cluster-specific models and multivariate models. The
q>+!Ete1p design effect was assumed to be additive and an adjustment
HMD\)vMK6 made in the variance by adding the variance associated with
dOaOWMrfdf the design effect prior to constructing the 95% confidence
R.1.
LB limits.
ByE@4+9 RESULTS
_gH$
,.j/ Study population
_rSwQ<38> A total of 3271 (83%) of the Melbourne residents, 403
_*z^PkH (90%) Melbourne nursing home residents, and 1473 (92%)
n"?*"Ya rural residents participated. In general, non-participants did
3ylSO73R not differ from participants.16 The study population was
jjrE8[ representative of the Victorian population and Australia as
Ca5LLG a whole.
]?V:+>t= The Melbourne residents ranged in age from 40 to
pcIS}+L 98 years (mean = 59) and 1511 (46%) were male. The
JS03BItt Melbourne nursing home residents ranged in age from 46 to
pq_U?_5Z'r 101 years (mean = 82) and 85 (21%) were men. The rural
'Jek<
5 residents ranged in age from 40 to 103 years (mean = 60)
;wJe%Nw? and 701 (47.5%) were men.
e2fv
% Prevalence of cataract and prior cataract surgery
Y9-F\t=~ As would be expected, the rate of any cataract increases
Xn~\Vb dramatically with age (Table 1). The weighted rate of any
EhKG"Lb+ cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
:
^paI Although the rates varied somewhat between the three
P
B-x_D strata, they were not significantly different as the 95% confidence
n5oX 51J limits overlapped. The per cent of cataractous eyes
iDcYyNE with best-corrected visual acuity of less than 6/12 was 12.5%
Jza?DhSAZ (65/520) for cortical cataract, 18% for nuclear cataract
mcidA% (97/534) and 14.4% (27/187) for PSC cataract. Cataract
;,uATd| surgery also rose dramatically with age. The overall
}%c>Hh weighted rate of prior cataract surgery in Victoria was
`gCJ[ 3.79% (95% CL 2.97, 4.60) (Table 2).
`<P:ly. Risk factors for unoperated cataract
B1Pi+-t Cases of cataract that had not been removed were classified
]a.^F as unoperated cataract. Risk factor analyses for unoperated
Y^DGnx("m cataract were not performed with the nursing home residents
pUqNB_ as information about risk factor exposure was not
KiFTj$w, available for this cohort. The following factors were assessed
gH,Pz in relation to unoperated cataract: age, sex, residence
eU`O=uE (urban/rural), language spoken at home (a measure of ethnic
3P>1-= integration), country of birth, parents’ country of birth (a
_iDVd2X"H measure of ethnicity), years since migration, education, use
(GGosXU-v of ophthalmic services, use of optometric services, private
y<m[9FC} health insurance status, duration of distance glasses use,
#*w)rGkU2 glaucoma, age-related maculopathy and employment status.
{98e_z w In this cross sectional study it was not possible to assess the
Z'uiU e`& level of visual acuity that would predict a patient’s having
=vQ J2Rg cataract surgery, as visual acuity data prior to cataract
f8WI@]1F surgery were not available.
X<$DNRN The significant risk factors for unoperated cataract in univariate
An`*![ analyses were related to: whether a participant had
4W49*Je ever seen an optometrist, seen an ophthalmologist or been
yH43Yo#Rk diagnosed with glaucoma; and participants’ employment
XR[=W(m} status (currently employed) and age. These significant
/J!:_Nq factors were placed in a backwards stepwise logistic regression
E8R;S}PA model. The factors that remained significantly related
8HZ+r/j to unoperated cataract were whether participants had ever
d:^B2~j seen an ophthalmologist, seen an optometrist and been
Z
zp"CK 5 diagnosed with glaucoma. None of the demographic factors
P,3w
b were associated with unoperated cataract in the multivariate
HOCj* O4 model.
Ok\X%avq The per cent of participants with unoperated cataract
j!%^6Io4 who said that they were dissatisfied or very dissatisfied with
|</) 6r Operated and unoperated cataract in Australia 79
; Ad5Jk Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
kQ lwl9 Age group Sex Urban Rural Nursing home Weighted total
cL03V? }
~ (years) (%) (%) (%)
+w?R4Sxjn 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
M;OMsRCVO Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
Sl ^PELU 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
hLk6Hqr7 Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
,5ZQPICF 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
]cmX f Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
:E~rve' 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
b l+g7 g; Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
02*qf:kTnA 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
udLI AV* Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
EEL3~H{( 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
%P
t){9b Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
G\;6n Age-standardized
?8GS*I (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)
o,*D8[ aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
"opMS/a"7 their current vision was 30% (290/683), compared with 27%
"2sk1 (26/95) of participants with prior cataract surgery (chisquared,
T>L?\- 1 d.f. = 0.25, P = 0.62).
SZHgXl3: Outcomes of cataract surgery
(?zD!%
k Two hundred and forty-nine eyes had undergone prior
<EN9s cataract surgery. Of these 249 operated eyes, 49 (20%) were
\I523$a left aphakic, 6 (2.4%) had anterior chamber intraocular
5ct&fjmR_ lenses and 194 (78%) had posterior chamber intraocular
DHw)]WB M lenses. The rate of capsulotomy in the eyes with intact
wT::b V{ posterior capsules was 36% (73/202). Fifteen per cent of
ja';NIO- eyes (17/114) with a clear posterior capsule had bestcorrected
]FTi2B{}H visual acuity of less than 6/12 compared with 43%
~qGW94 of eyes (6/14) with opaque capsules, and 15% of eyes
Dpw*m.f (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
Q^rR }Ws P = 0.027).
%6
0 OS3 The percentage of eyes with best-corrected visual acuity
d`B<\Y#{Us of 6/12 or better was 96% (302/314) for eyes without
x}?<9(nE c cataract, 88% (1417/1609) for eyes with prevalent cataract
qclc--fsE and 85% (211/249) for eyes with operated cataract (chisquared,
4<F
z![> 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
LtMM89u operated eyes (11%) had visual acuities of less than 6/18
cpltTJFg (moderate vision impairment) (Fig. 2). A cause of this
Q[7 i moderate visual impairment (but not the only cause) in four
E3wL n/< (15%) eyes was secondary to cataract surgery. Three of these
>{IPt]PCn four eyes had undergone intracapsular cataract extraction
CG=c@-"n/ and the fourth eye had an opaque posterior capsule. No one
UGhEaKH~R had bilateral vision impairment as a result of their cataract
IFX$\+- surgery.
Jd>~gA}l DISCUSSION
V >' To our knowledge, this is the first paper to systematically
cu0IFNF}[ assess the prevalence of current cataract, previous cataract
2(xC| surgery, predictors of unoperated cataract and the outcomes
'Be'!9K*d of cataract surgery in a population-based sample. The Visual
FRrp@hE Impairment Project is unique in that the sampling frame and
\% =\4%: high response rate have ensured that the study population is
zzQWHg]/ representative of Australians aged 40 years and over. Therefore,
lZ\8W^ these data can be used to plan age-related cataract
GrL{q;IO services throughout Australia.
Iv6 q(c We found the rate of any cataract in those over the age
5:h[%3'bB of 40 years to be 22%. Although relatively high, this rate is
5G*cAlU significantly less than was reported in a number of previous
/9w>:i81 studies,2,4,6 with the exception of the Casteldaccia Eye
:jLL IqhB Study.5 However, it is difficult to compare rates of cataract
%SM;B-/zHt between studies because of different methodologies and
}~XWtWbd- cataract definitions employed in the various studies, as well
yLX $SR as the different age structures of the study populations.
&r5q,l&@n Other studies have used less conservative definitions of
`C+<!)2 cataract, thus leading to higher rates of cataract as defined.
$"^K~5Q In most large epidemiologic studies of cataract, visual acuity
>1~
/:DJ has not been included in the definition of cataract.
_IDZ.\'>$ Therefore, the prevalence of cataract may not reflect the
$<^t][{ actual need for cataract surgery in the community.
IU%|K~_n 80 McCarty et al.
@w[i%F,&` Table 2. Prevalence of previous cataract by age, gender and cohort
ut{T:kT Age group Gender Urban Rural Nursing home Weighted total
>gk_kl
Lh (years) (%) (%) (%)
V2YK T,5 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
%BqaVOKJ"f Female 0.00 0.00 0.00 0.00 (
qLN^9PdEE 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
|\5^ub,m Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
tMIYVHGy 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
ggr Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
`2s!%/ 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
_u`YjzK Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
P3$eomX' 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
tli.g Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
/Rp]"S
vt 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
C|(A/b Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
7|P
kc(O Age-standardized
yBIlwN`kB (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)
`BPTcL<W Figure 2. Visual acuity in eyes that had undergone cataract
y7R#PkQ~ surgery, n = 249. h, Presenting; j, best-corrected.
-EjXVn! vQ Operated and unoperated cataract in Australia 81
i=8iK#2 h The weighted prevalence of prior cataract surgery in the
GP|=4T}Bf Visual Impairment Project (3.6%) was similar to the crude
IP~!E_e}\ rate in the Beaver Dam Eye Study4 (3.1%), but less than the
JE?p'77C crude rate in the Blue Mountains Eye Study6 (6.0%).
)s2] -n}W However, the age-standardized rate in the Blue Mountains
WL$^B@gXQ Eye Study (standardized to the age distribution of the urban
L"L3n,%F Visual Impairment Project cohort) was found to be less than
YdY-Jg Xm the Visual Impairment Project (standardized rate = 1.36%,
E-MPFL 95% CL 1.25, 1.47). The incidence of cataract surgery in
5sD,gZ7 Australia has exceeded population growth.1 This is due,
[\u
R3$j# perhaps, to advances in surgical techniques and lens
_B4&Fb. implants that have changed the risk–benefit ratio.
c
pY{o^ The Global Initiative for the Elimination of Avoidable
0ju1>.p Blindness, sponsored by the World Health Organization,
9N]Xa states that cataract surgical services should be provided that
Rd?}<L ‘have a high success rate in terms of visual outcome and
Otn,UoeeB improved quality of life’,17 although the ‘high success rate’ is
R+sT
&d not defined. Population- and clinic-based studies conducted
4 p_C+4 in the United States have demonstrated marked improvement
."K>h3(&V in visual acuity following cataract surgery.18–20 We
mp|pz%U found that 85% of eyes that had undergone cataract extraction
g
jF5~
` had visual acuity of 6/12 or better. Previously, we have
@0`A!5h?u shown that participants with prevalent cataract in this
&}ZmT>q`$ cohort are more likely to express dissatisfaction with their
> =>/~dIb current vision than participants without cataract or participants
K
+7 with prior cataract surgery.21 In a national study in the
]`o5eByo United States, researchers found that the change in patients’
WSThhI
ratings of their vision difficulties and satisfaction with their
wI#8|,]"z vision after cataract surgery were more highly related to
1CtUf7 `/Q their change in visual functioning score than to their change
p<R:[rz in visual acuity.19 Furthermore, improvement in visual function
y48]|%73 has been shown to be associated with improvement in
KaIKb=4L| overall quality of life.22
91
jRIB A recent review found that the incidence of visually
-K"'F`;W significant posterior capsule opacification following
&K[*vyD cataract surgery to be greater than 25%.23 We found 36%
?z
,!iK` capsulotomy in our population and that this was associated
ycGY5t@K@ with visual acuity similar to that of eyes with a clear
K2m>D=w capsule, but significantly better than that of eyes with an
Xj?Wvt opaque capsule.
"EW8ll7r A number of studies have shown that the demand and
:XKYfc_y timing of cataract surgery vary according to visual acuity,
On C)f degree of handicap and socioeconomic factors.8–10,24,25 We
5zuwqOD* have also shown previously that ophthalmologists are more
lR(9;3 likely to refer a patient for cataract surgery if the patient is
*MJm: employed and less likely to refer a nursing home resident.7
37bM
e@W In the Visual Impairment Project, we did not find that any
_S!^=9bJ particular subgroup of the population was at greater risk of
J%|?[{rO{' having unoperated cataract. Universal access to health care
&lc@]y8 in Australia may explain the fact that people without
X<ex
>sM Medicare are more likely to delay cataract operations in the
N,t9X7G& USA,8 but not having private health insurance is not associated
rcnH ^P with unoperated cataract in Australia.
= XZU9df In summary, cataract is a significant public health problem
Zl
V in that one in four people in their 80s will have had cataract
+]l?JKV surgery. The importance of age-related cataract surgery will
"+DA)K increase further with the ageing of the population: the
ITPE2x number of people over age 60 years is expected to double in
Zy0M\-Mn the next 20 years. Cataract surgery services are well
)1 <0c@g= accessed by the Victorian population and the visual outcomes
j
}~?&yB of cataract surgery have been shown to be very good.
(6%T~|a These data can be used to plan for age-related cataract
H4i}gdR surgical services in Australia in the future as the need for
P0N/bp2Uy cataract extractions increases.
L
3]J8oEmU ACKNOWLEDGEMENTS
2[
sY?C The Visual Impairment Project was funded in part by grants
z/Lb1ND8 from the Victorian Health Promotion Foundation, the
V[ UOlJ National Health and Medical Research Council, the Ansell
as07~Xvp- Ophthalmology Foundation, the Dorothy Edols Estate and
_JH.&8 the Jack Brockhoff Foundation. Dr McCarty is the recipient
5nPvEN
/ of a Wagstaff Fellowship in Ophthalmology from the Royal
;NP-tA) Victorian Eye and Ear Hospital.
AArLNXzVW REFERENCES
]t[%.^5# 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
Rsx6vF8]5 Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
NT6jwK.?)? 2. Sperduto RD, Hiller R. The prevalence of nuclear, cortical,
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