ABSTRACT
w=Ai?u Purpose: To quantify the prevalence of cataract, the outcomes
KmS$CFsGL of cataract surgery and the factors related to
{9?++G"\ unoperated cataract in Australia.
`#@#eZ Methods: Participants were recruited from the Visual
k{\wjaf) Impairment Project: a cluster, stratified sample of more than
NZT2ni4 5000 Victorians aged 40 years and over. At examination
j11FEE<W sites interviews, clinical examinations and lens photography
vd<r}3i* were performed. Cataract was defined in participants who
)(bAi had: had previous cataract surgery, cortical cataract greater
h0**[LDH than 4/16, nuclear greater than Wilmer standard 2, or
A c^hZ.qPz posterior subcapsular greater than 1 mm2.
pHKcKqB*13 Results: The participant group comprised 3271 Melbourne
c{.y9P6 residents, 403 Melbourne nursing home residents and 1473
?e=3G4N rural residents.The weighted rate of any cataract in Victoria
10tlD<eYb was 21.5%. The overall weighted rate of prior cataract
$ljzw@k surgery was 3.79%. Two hundred and forty-nine eyes had
<S[]VXy had prior cataract surgery. Of these 249 procedures, 49
h]6m+oPW (20%) were aphakic, 6 (2.4%) had anterior chamber
#*;G8yV intraocular lenses and 194 (78%) had posterior chamber
.+3~
w intraocular lenses.Two hundred and eleven of these operated
813t=A eyes (85%) had best-corrected visual acuity of 6/12 or
Gx)U~L$B better, the legal requirement for a driver’s license.Twentyseven
|)KOy~" (11%) had visual acuity of less than 6/18 (moderate
y@XE! L vision impairment). Complications of cataract surgery
]g] ]\hS caused reduced vision in four of the 27 eyes (15%), or 1.9%
. E8Gj'yO of operated eyes. Three of these four eyes had undergone
shkyN intracapsular cataract extraction and the fourth eye had an
>DM^/EAG{ opaque posterior capsule. No one had bilateral vision
.@KI,_X6, impairment as a result of cataract surgery. Surprisingly, no
.n\j<Kq particular demographic factors (such as age, gender, rural
P>}OwW residence, occupation, employment status, health insurance
%ztv.K(8 status, ethnicity) were related to the presence of unoperated
;9MIapfUd( cataract.
Vq&}i~ Conclusions: Although the overall prevalence of cataract is
`;
+UWdAR quite high, no particular subgroup is systematically underserviced
sq rY<@% in terms of cataract surgery. Overall, the results of
QnJd}(yN cataract surgery are very good, with the majority of eyes
Q30TR achieving driving vision following cataract extraction.
<D`VFSEJ Key words: cataract extraction, health planning, health
.;J6)h services accessibility, prevalence
0<[g7BbR INTRODUCTION
4k_y;$4WN Cataract is the leading cause of blindness worldwide and, in
cj;k{Moc Australia, cataract extractions account for the majority of all
STjk<DP( ophthalmic procedures.1 Over the period 1985–94, the rate
dKpUw9C#/ of cataract surgery in Australia was twice as high as would be
+\x}1bNS%j expected from the growth in the elderly population.1
_aP2gH Although there have been a number of studies reporting
IY,n7x0d the prevalence of cataract in various populations,2–6 there is
GHRr+ little information about determinants of cataract surgery in
QTIC5cl, the population. A previous survey of Australian ophthalmologists
"1wjh=@z showed that patient concern and lifestyle, rather
g/+|gHq^ than visual acuity itself, are the primary factors for referral
-|2k$W for cataract surgery.7 This supports prior research which has
Pi5($cn shown that visual acuity is not a strong predictor of need for
*@eZt*_ cataract surgery.8,9 Elsewhere, socioeconomic status has
\AOHZ r been shown to be related to cataract surgery rates.10
cqG&n0
zb To appropriately plan health care services, information is
HSj=g}r needed about the prevalence of age-related cataract in the
@/8O@^ community as well as the factors associated with cataract
p~yGp]yJ9 surgery. The purpose of this study is to quantify the prevalence
24I\smO of any cataract in Australia, to describe the factors
"IJ 9vXI related to unoperated cataract in the community and to
a v"dJm describe the visual outcomes of cataract surgery.
=X3Rk)2r METHODS
F;8
Uvj Study population
&PUn,9 Rm Details about the study methodology for the Visual
l.uW>AoLh Impairment Project have been published previously.11
.cK<jF@' Briefly, cluster sampling within three strata was employed to
B8 r#o=q1 recruit subjects aged 40 years and over to participate.
`zOn(6B;U Within the Melbourne Statistical Division, nine pairs of
h\/T b8 census collector districts were randomly selected. Fourteen
oAF#bj_f nursing homes within a 5 km radius of these nine test sites
{JtfEna were randomly chosen to recruit nursing home residents.
)@_5}8 Clinical and Experimental Ophthalmology (2000) 28, 77–82
r*g<A2g% Original Article
MI,kKi Operated and unoperated cataract in Australia
e=Q{CsP Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
}K|40oO5 Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
Q tl!
f n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
y eWB.M~X Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au "H|hN 78 McCarty et al.
H|z:j35\ Finally, four pairs of census collector districts in four rural
5OC{_- Victorian communities were randomly selected to recruit rural
^oDSU7j5, residents. A household census was conducted to identify
CD pLV: eligible residents aged 40 years and over who had been a
&5
n0
J resident at that address for at least 6 months. At the time of
M,g$ the household census, basic information about age, sex,
S?u@3PyJm country of birth, language spoken at home, education, use of
mI,!8# corrective spectacles and use of eye care services was collected.
Ja{[T Eligible residents were then invited to attend a local
"f4atuuXa examination site for a more detailed interview and examination.
'Omj-o'tn9 The study protocol was approved by the Royal Victorian
aK]H(F2# Eye and Ear Hospital Human Research Ethics Committee.
`J-&Y2_/k Assessment of cataract
c52S2f7 A standardized ophthalmic examination was performed after
h[oI/X pupil dilatation with one drop of 10% phenylephrine
jbTsrj"g hydrochloride. Lens opacities were graded clinically at the
fvr|<3ojo time of the examination and subsequently from photos using
Qn`Fq,uvL the Wilmer cataract photo-grading system.12 Cortical and
t&H3yV posterior subcapsular (PSC) opacities were assessed on
p~17cH4~-f retroillumination and measured as the proportion (in 1/16)
>=d%t6%( of pupil circumference occupied by opacity. For this analysis,
,o sM|!, cortical cataract was defined as 4/16 or greater opacity,
C]NL9Gq` PSC cataract was defined as opacity equal to or greater than
=v7%IRP5 1 mm2 and nuclear cataract was defined as opacity equal to
o|nN0z)b4 or greater than Wilmer standard 2,12 independent of visual
DGO\&^GT^ acuity. Examples of the minimum opacities defined as cortical,
O^sOv!!RH/ nuclear and PSC cataract are presented in Figure 1.
|6!L\/}M% Bilateral congenital cataracts or cataracts secondary to
~JG\b?s intraocular inflammation or trauma were excluded from the
>rid3~ analysis. Two cases of bilateral secondary cataract and eight
.a7!*I#g cases of bilateral congenital cataract were excluded from the
l G $s( analyses.
_!E)a A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
^e(
*{K;8 Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
D\k'Eez height set to an incident angle of 30° was used for examinations.
48RSuH Ektachrome® 200 ASA colour slide film (Eastman
ws< (LH Kodak Company, Rochester, NY, USA) was used to photograph
k.!m-5E the nuclear opacities. The cortical opacities were
WFG`-8_e[I photographed with an Oxford® retroillumination camera
F-PQ`@ZNW (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
Z Z9D6+R film (Eastman Kodak). Photographs were graded separately
L'r gCOJ< by two research assistants and discrepancies were adjudicated
GDY=^r by an independent reviewer. Any discrepancies
s_%KWkS between the clinical grades and the photograph grades were
\JbOT%1 resolved. Except in cases where photographs were missing,
k%%0"+y#a the photograph grades were used in the analyses. Photograph
z~Is
E8 grades were available for 4301 (84%) for cortical
$
$e"[g cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
f]48>LRE8 for PSC cataract. Cataract status was classified according to
Ft 6{g
JBG the severity of the opacity in the worse eye.
_:~I(c6 Assessment of risk factors
]i
Yp A standardized questionnaire was used to obtain information
L&hv:+3N about education, employment and ethnic background.11
Eal*){"<,? Specific information was elicited on the occurrence, duration
W[t0hbVw and treatment of a number of medical conditions,
l$ufW| including ocular trauma, arthritis, diabetes, gout, hypertension
5F$~ZDu and mental illness. Information about the use, dose and
^=[b]
*V duration of tobacco, alcohol, analgesics and steriods were
;S+]Z!5LT collected, and a food frequency questionnaire was used to
f f5 e]^, determine current consumption of dietary sources of antioxidants
SGP)A(,k9
and use of vitamin supplements.
Q/`W[Et Data management and statistical analysis
|vtj0,[ Data were collected either by direct computer entry with a
[Zne19/ questionnaire programmed in Paradox© (Carel Corporation,
f"R'Q|7D Ottawa, Canada) with internal consistency checks, or
^NXxMC(e+ on self-coding forms. Open-ended responses were coded at
'a G`qPB a later time. Data that were entered on the self-coded forms
7mA:~- .u were entered into a computer with double data entry and
dy3fZ(=q^ reconciliation of any inconsistencies. Data range and consistency
8 `}I] checks were performed on the entire data set.
<+_WMSf;4 SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
?H!QV;ku employed for statistical analyses.
Ynl Zyw! Ninety-five per cent confidence limits around the agespecific
GTke<R rates were calculated according to Cochran13 to
a/xnf<(H account for the effect of the cluster sampling. Ninety-five
9k;%R5( per cent confidence limits around age-standardized rates
/ "@cv{ were calculated according to Breslow and Day.14 The strataspecific
5xhYOwQBo data were weighted according to the 1996
&] O^d4/ Australian Bureau of Statistics census data15 to reflect the
sp6A*mwl cataract prevalence in the entire Victorian population.
LAY~hF" Univariate analyses with Student’s t-tests and chi-squared
h-6x! 6pm tests were first employed to evaluate risk factors for unoperated
(BGflb cataract. Any factors with P < 0.10 were then fitted
UBw*}p into a backwards stepwise logistic regression model. For the
(}
wMU]!_ Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
-nqq;|% final multivariate models, P < 0.05 was considered statistically
K"8! significant. Design effect was assessed through the use
UN|S!&C$
of cluster-specific models and multivariate models. The
\m#{{SGm design effect was assumed to be additive and an adjustment
IQQ>0^Q~ made in the variance by adding the variance associated with
)i<Qg.@MX the design effect prior to constructing the 95% confidence
Pr3>}4M limits.
p8MN>pLP%
RESULTS
#9t3 <H[ Study population
T@d4NF# A total of 3271 (83%) of the Melbourne residents, 403
{bNVNG^ (90%) Melbourne nursing home residents, and 1473 (92%)
C?g<P0h rural residents participated. In general, non-participants did
EZ[e
a< not differ from participants.16 The study population was
"Ug+#;}p$ representative of the Victorian population and Australia as
J7wIA3.O a whole.
CP
Ju= The Melbourne residents ranged in age from 40 to
B#4'3Y-3 98 years (mean = 59) and 1511 (46%) were male. The
/%TL{k&m$ Melbourne nursing home residents ranged in age from 46 to
]{18-= 101 years (mean = 82) and 85 (21%) were men. The rural
uP.dCs9- residents ranged in age from 40 to 103 years (mean = 60)
Wa9yyc and 701 (47.5%) were men.
xn anca
Prevalence of cataract and prior cataract surgery
6Oy6r
As would be expected, the rate of any cataract increases
{/i&o dramatically with age (Table 1). The weighted rate of any
T>w;M?`9K cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
*mn"GK6 Although the rates varied somewhat between the three
^M+aQg% strata, they were not significantly different as the 95% confidence
]>[0DX]j limits overlapped. The per cent of cataractous eyes
XQZiJ
%' with best-corrected visual acuity of less than 6/12 was 12.5%
KxDfPd+j[ (65/520) for cortical cataract, 18% for nuclear cataract
|k]fY*z( (97/534) and 14.4% (27/187) for PSC cataract. Cataract
4jC7>mE surgery also rose dramatically with age. The overall
s3=slWY= weighted rate of prior cataract surgery in Victoria was
Z61
L;E 3.79% (95% CL 2.97, 4.60) (Table 2).
'ql<R0g Risk factors for unoperated cataract
oG
c9
6B% Cases of cataract that had not been removed were classified
Nt687 as unoperated cataract. Risk factor analyses for unoperated
dw%g9DT cataract were not performed with the nursing home residents
;WG%)^e as information about risk factor exposure was not
(V0KmNCW` available for this cohort. The following factors were assessed
!{vZvy" in relation to unoperated cataract: age, sex, residence
v.c.5@%%o (urban/rural), language spoken at home (a measure of ethnic
J7@Q;gcl: integration), country of birth, parents’ country of birth (a
%2'Y@AX` measure of ethnicity), years since migration, education, use
YMj iJTl of ophthalmic services, use of optometric services, private
*!yA'z< health insurance status, duration of distance glasses use,
|Rz}bsrZ glaucoma, age-related maculopathy and employment status.
Z<'iT%6+r In this cross sectional study it was not possible to assess the
jWso'K level of visual acuity that would predict a patient’s having
ps*iE=D cataract surgery, as visual acuity data prior to cataract
B.
~[m} surgery were not available.
?(M]'ia{ The significant risk factors for unoperated cataract in univariate
~J
>Jd analyses were related to: whether a participant had
\/9 O5`u*V ever seen an optometrist, seen an ophthalmologist or been
t-SZBNb diagnosed with glaucoma; and participants’ employment
C|]Zpn#{K status (currently employed) and age. These significant
~;uU{TT factors were placed in a backwards stepwise logistic regression
z6f
Y_LL model. The factors that remained significantly related
XII'
,& to unoperated cataract were whether participants had ever
)"%J~:`h} seen an ophthalmologist, seen an optometrist and been
"ZuA._ diagnosed with glaucoma. None of the demographic factors
Wr+1e1[ were associated with unoperated cataract in the multivariate
RY\0dv> model.
ek
d[|g The per cent of participants with unoperated cataract
W>u{JgY who said that they were dissatisfied or very dissatisfied with
dwb ^z+ Operated and unoperated cataract in Australia 79
w8F`RRHEE Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
XE#$|Z Age group Sex Urban Rural Nursing home Weighted total
[S0wwWU |0 (years) (%) (%) (%)
iKv"200h( 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
gCbS$Pw Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
vZPBjloT!. 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
W)L*zVj~ Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
hb1eEn
60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
gO/\Yi Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
biRkqc; 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
kpMo7n Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
{D8yqO A} 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
#Fkp6`Q$x Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
!Oi':OQG 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
whFJ] Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
xRZ/[1f! Age-standardized
%8>0;ktU (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
BW ux! aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
gOMy8w4> their current vision was 30% (290/683), compared with 27%
EtQ:x$S_ (26/95) of participants with prior cataract surgery (chisquared,
cI-@
nV 1 d.f. = 0.25, P = 0.62).
Q'YakEv >= Outcomes of cataract surgery
vi` VK&+r Two hundred and forty-nine eyes had undergone prior
AB<%GzW0( cataract surgery. Of these 249 operated eyes, 49 (20%) were
Az/B/BLB left aphakic, 6 (2.4%) had anterior chamber intraocular
w8zr0z lenses and 194 (78%) had posterior chamber intraocular
*d31fBCk% lenses. The rate of capsulotomy in the eyes with intact
Uy@:-NC)kn posterior capsules was 36% (73/202). Fifteen per cent of
UK)wV
eyes (17/114) with a clear posterior capsule had bestcorrected
t_+owiF)M visual acuity of less than 6/12 compared with 43%
&AVX03P of eyes (6/14) with opaque capsules, and 15% of eyes
Iu^I?c[ (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
h<qi[d4X P = 0.027).
+}eK8>2 The percentage of eyes with best-corrected visual acuity
*;Za)) of 6/12 or better was 96% (302/314) for eyes without
O\h%ZLjfO cataract, 88% (1417/1609) for eyes with prevalent cataract
M|R\[
Zf and 85% (211/249) for eyes with operated cataract (chisquared,
-fN5-AC 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
8Nx fYA operated eyes (11%) had visual acuities of less than 6/18
>)k[085t (moderate vision impairment) (Fig. 2). A cause of this
yoz-BS moderate visual impairment (but not the only cause) in four
T
"#DhEM (15%) eyes was secondary to cataract surgery. Three of these
'@5x=> four eyes had undergone intracapsular cataract extraction
W{1l?Wo and the fourth eye had an opaque posterior capsule. No one
[}4\CWM had bilateral vision impairment as a result of their cataract
%.8(R
& surgery.
_qH]OSo
DISCUSSION
uWi pjxS To our knowledge, this is the first paper to systematically
M0hR]4T assess the prevalence of current cataract, previous cataract
fw|t`mUGu surgery, predictors of unoperated cataract and the outcomes
N:EljzvP} of cataract surgery in a population-based sample. The Visual
`%~f5< Impairment Project is unique in that the sampling frame and
b,
47
EJ} high response rate have ensured that the study population is
Equ%6x representative of Australians aged 40 years and over. Therefore,
hMgk+4* these data can be used to plan age-related cataract
SQN{/")T services throughout Australia.
5f75r We found the rate of any cataract in those over the age
#v4^,$k> of 40 years to be 22%. Although relatively high, this rate is
T0 cm+|S significantly less than was reported in a number of previous
!:~C/B{ studies,2,4,6 with the exception of the Casteldaccia Eye
DLO#_t^v. Study.5 However, it is difficult to compare rates of cataract
yr)e."#S between studies because of different methodologies and
|aj]]l[@S cataract definitions employed in the various studies, as well
`:2np{ as the different age structures of the study populations.
|7.X)h` Other studies have used less conservative definitions of
r^S
o
qom3 cataract, thus leading to higher rates of cataract as defined.
K
k^!P*# In most large epidemiologic studies of cataract, visual acuity
z;>O5
a>z has not been included in the definition of cataract.
$>Gf;k Therefore, the prevalence of cataract may not reflect the
d8WEsQ+)A actual need for cataract surgery in the community.
R
G/P] 80 McCarty et al.
)
urUaE Table 2. Prevalence of previous cataract by age, gender and cohort
!H @nAz Age group Gender Urban Rural Nursing home Weighted total
F^!mgU X (years) (%) (%) (%)
"T} HH 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
2O2d*Ld> Female 0.00 0.00 0.00 0.00 (
Z
eWstw7 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
T n,Ifo3 Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
])WIw'L! 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
z7a@'+' Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
sZokiFJ 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
d"+ _`d=` Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
!
n?j)p. 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
=.9tRq Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
+:z%#D 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
*y W9-( Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
w Qp{
z Age-standardized
~s[Yu!( (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)
>k
u7{1) Figure 2. Visual acuity in eyes that had undergone cataract
QSOJHRl=C surgery, n = 249. h, Presenting; j, best-corrected.
L/O:V^1 Operated and unoperated cataract in Australia 81
q,j` _
R4 The weighted prevalence of prior cataract surgery in the
,Lw
'3
Visual Impairment Project (3.6%) was similar to the crude
&MP8.(u ` rate in the Beaver Dam Eye Study4 (3.1%), but less than the
79U7<]-! crude rate in the Blue Mountains Eye Study6 (6.0%).
iHyA;'!Os However, the age-standardized rate in the Blue Mountains
+@
#-S Eye Study (standardized to the age distribution of the urban
1;+(HB Visual Impairment Project cohort) was found to be less than
iS28p the Visual Impairment Project (standardized rate = 1.36%,
N_E:?Jo 95% CL 1.25, 1.47). The incidence of cataract surgery in
O[&G6+ Australia has exceeded population growth.1 This is due,
71Mk!E=1 perhaps, to advances in surgical techniques and lens
T<ekDhlr implants that have changed the risk–benefit ratio.
cU r'mb The Global Initiative for the Elimination of Avoidable
<1E*wPm8 Blindness, sponsored by the World Health Organization,
4_?*@L1 states that cataract surgical services should be provided that
Jm
G)=$, ‘have a high success rate in terms of visual outcome and
[Uu!:SZ improved quality of life’,17 although the ‘high success rate’ is
C$EvcF%1 not defined. Population- and clinic-based studies conducted
9=;ETLL " in the United States have demonstrated marked improvement
^2um.`8 in visual acuity following cataract surgery.18–20 We
_6Fj&mw(u found that 85% of eyes that had undergone cataract extraction
q
oVp@=\:" had visual acuity of 6/12 or better. Previously, we have
:+|os" shown that participants with prevalent cataract in this
1:lhZFZ cohort are more likely to express dissatisfaction with their
$+a2CZs! current vision than participants without cataract or participants
X2p9KC with prior cataract surgery.21 In a national study in the
vc(6lN9> United States, researchers found that the change in patients’
b7bbrR8 ratings of their vision difficulties and satisfaction with their
ySwvjP7f vision after cataract surgery were more highly related to
lTpmoDa% their change in visual functioning score than to their change
%8yX6`lH in visual acuity.19 Furthermore, improvement in visual function
geu8$^ has been shown to be associated with improvement in
g4^df%)& overall quality of life.22
9rsty{J8 A recent review found that the incidence of visually
j*jO809%^ significant posterior capsule opacification following
`7zNVYur8 cataract surgery to be greater than 25%.23 We found 36%
]`x\Oj& capsulotomy in our population and that this was associated
we&g9j' with visual acuity similar to that of eyes with a clear
)/F1,&/N`e capsule, but significantly better than that of eyes with an
YS5 Pt)? opaque capsule.
64OgE! A number of studies have shown that the demand and
%maLo RJ timing of cataract surgery vary according to visual acuity,
3yu{Q z5y, degree of handicap and socioeconomic factors.8–10,24,25 We
N8|
;X have also shown previously that ophthalmologists are more
.q1OT> likely to refer a patient for cataract surgery if the patient is
j6KGri employed and less likely to refer a nursing home resident.7
*a7&v3X In the Visual Impairment Project, we did not find that any
Q1Sf7) particular subgroup of the population was at greater risk of
Y&k6Xhuao having unoperated cataract. Universal access to health care
;$\d^i{N in Australia may explain the fact that people without
`\:92+ Medicare are more likely to delay cataract operations in the
wU#79:h
USA,8 but not having private health insurance is not associated
0 ej!!WP with unoperated cataract in Australia.
L+PrV y In summary, cataract is a significant public health problem
+_HPZo in that one in four people in their 80s will have had cataract
F~dq7AS surgery. The importance of age-related cataract surgery will
}F1|&
A increase further with the ageing of the population: the
ZgL4$% number of people over age 60 years is expected to double in
zM^ux!T= the next 20 years. Cataract surgery services are well
W
,iSN} accessed by the Victorian population and the visual outcomes
/u
}AgIb of cataract surgery have been shown to be very good.
N6Fj}m&E These data can be used to plan for age-related cataract
;Bo{.916 surgical services in Australia in the future as the need for
H/p<lp cataract extractions increases.
$Blo`' ACKNOWLEDGEMENTS
Z_Ox ' The Visual Impairment Project was funded in part by grants
h*f= from the Victorian Health Promotion Foundation, the
%QUV351H National Health and Medical Research Council, the Ansell
Q9N=yz Ophthalmology Foundation, the Dorothy Edols Estate and
h5G>FPM-= the Jack Brockhoff Foundation. Dr McCarty is the recipient
8W 9%NW3& of a Wagstaff Fellowship in Ophthalmology from the Royal
O&=?,zLO[ Victorian Eye and Ear Hospital.
#~54t0|Cd> REFERENCES
9N|O*h1;u 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
R/M:~h~F! Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
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