ABSTRACT
Ln:6@Ok)5% Purpose: To quantify the prevalence of cataract, the outcomes
GsIVx
! of cataract surgery and the factors related to
[wU e"{ unoperated cataract in Australia.
T_R2BBT
v
Methods: Participants were recruited from the Visual
/2^"c+/'p Impairment Project: a cluster, stratified sample of more than
)5T82=[h< 5000 Victorians aged 40 years and over. At examination
fi%)520 sites interviews, clinical examinations and lens photography
YI+ clh;%9 were performed. Cataract was defined in participants who
Q^\m@7O
: had: had previous cataract surgery, cortical cataract greater
V>Dqw! than 4/16, nuclear greater than Wilmer standard 2, or
W(pq_H' posterior subcapsular greater than 1 mm2.
)
>;7"v Results: The participant group comprised 3271 Melbourne
Ri>4:V3K residents, 403 Melbourne nursing home residents and 1473
T@wgWE<0y_ rural residents.The weighted rate of any cataract in Victoria
Q":,oZ2 was 21.5%. The overall weighted rate of prior cataract
:@uIEvD? surgery was 3.79%. Two hundred and forty-nine eyes had
vf&_
N had prior cataract surgery. Of these 249 procedures, 49
W4;/;[/L (20%) were aphakic, 6 (2.4%) had anterior chamber
IR2=dQS intraocular lenses and 194 (78%) had posterior chamber
fj|b;8_}l intraocular lenses.Two hundred and eleven of these operated
pfBe24q eyes (85%) had best-corrected visual acuity of 6/12 or
Ff{,zfN+3 better, the legal requirement for a driver’s license.Twentyseven
K| dI'TnW (11%) had visual acuity of less than 6/18 (moderate
cY5w,.Q/! vision impairment). Complications of cataract surgery
z$gtGrU caused reduced vision in four of the 27 eyes (15%), or 1.9%
l+#J oc<8 of operated eyes. Three of these four eyes had undergone
X+1Mv intracapsular cataract extraction and the fourth eye had an
rD+mI/_J` opaque posterior capsule. No one had bilateral vision
[#=IKsO'R6 impairment as a result of cataract surgery. Surprisingly, no
W#)X@TlE particular demographic factors (such as age, gender, rural
0G31Kou residence, occupation, employment status, health insurance
bwM?DY status, ethnicity) were related to the presence of unoperated
C}#$wge
cataract.
^T:L6: Conclusions: Although the overall prevalence of cataract is
^@3,/dH1 t quite high, no particular subgroup is systematically underserviced
It7R}0Smg in terms of cataract surgery. Overall, the results of
k#bG&BF cataract surgery are very good, with the majority of eyes
@@j:z;^| achieving driving vision following cataract extraction.
ua"2nVxK_K Key words: cataract extraction, health planning, health
PB
*v45 services accessibility, prevalence
)s,LFIy<A INTRODUCTION
Nm
!~h|3 Cataract is the leading cause of blindness worldwide and, in
)X;051Q Australia, cataract extractions account for the majority of all
2}=@n*8*d ophthalmic procedures.1 Over the period 1985–94, the rate
hxzA1s%~ of cataract surgery in Australia was twice as high as would be
,-hbwd~M expected from the growth in the elderly population.1
,{mv6?_ Although there have been a number of studies reporting
c<, LE@V the prevalence of cataract in various populations,2–6 there is
=&6sU{j* little information about determinants of cataract surgery in
obE8iG@H the population. A previous survey of Australian ophthalmologists
WW.@S5 showed that patient concern and lifestyle, rather
=\_gT=tZ than visual acuity itself, are the primary factors for referral
!ej]'>V,X for cataract surgery.7 This supports prior research which has
j g//I<D shown that visual acuity is not a strong predictor of need for
]Zt ]wnL+ cataract surgery.8,9 Elsewhere, socioeconomic status has
PWZd< been shown to be related to cataract surgery rates.10
=6qTz3t To appropriately plan health care services, information is
#M{qMJHDo needed about the prevalence of age-related cataract in the
e@qH!.g) community as well as the factors associated with cataract
]
+46r!r| surgery. The purpose of this study is to quantify the prevalence
WPkKbF of any cataract in Australia, to describe the factors
z~X
/.> related to unoperated cataract in the community and to
g9q}D- describe the visual outcomes of cataract surgery.
CvmIDRP* METHODS
[nZIV
Study population
BGBHA"5fz Details about the study methodology for the Visual
JLnv O Impairment Project have been published previously.11
GLyPgZ`| Briefly, cluster sampling within three strata was employed to
4MS#`E7LrC recruit subjects aged 40 years and over to participate.
?"r=08 Within the Melbourne Statistical Division, nine pairs of
*Q^z4UY census collector districts were randomly selected. Fourteen
E0R6qS:' nursing homes within a 5 km radius of these nine test sites
_<LL@
IX were randomly chosen to recruit nursing home residents.
A
$gn{ c Clinical and Experimental Ophthalmology (2000) 28, 77–82
w+>+hq Original Article
<|4$TH^t Operated and unoperated cataract in Australia
t$z[ja= Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
sde>LZet/ Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
A$3Rbn}" n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
GM0Q@`d Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au P2a5<#_| 78 McCarty et al.
s@
r{TXEn Finally, four pairs of census collector districts in four rural
Q0Ft.b Victorian communities were randomly selected to recruit rural
3{$7tck, residents. A household census was conducted to identify
8^>c_%e} eligible residents aged 40 years and over who had been a
&jHsFS resident at that address for at least 6 months. At the time of
\~ChbPnc the household census, basic information about age, sex,
'ZW(Hjrd country of birth, language spoken at home, education, use of
Mg.%&vH\ corrective spectacles and use of eye care services was collected.
nf0u:M"fm Eligible residents were then invited to attend a local
)pH+ibR examination site for a more detailed interview and examination.
*z?Uh$I4 The study protocol was approved by the Royal Victorian
3NgXM Eye and Ear Hospital Human Research Ethics Committee.
FKTF?4+\U Assessment of cataract
>\Dy A standardized ophthalmic examination was performed after
k0e}`#t pupil dilatation with one drop of 10% phenylephrine
N s +g9+<A hydrochloride. Lens opacities were graded clinically at the
0I)$!1~O)
time of the examination and subsequently from photos using
'\I(n|\ the Wilmer cataract photo-grading system.12 Cortical and
]=00<~ l*q posterior subcapsular (PSC) opacities were assessed on
y("WnVI retroillumination and measured as the proportion (in 1/16)
'q-q4QCB of pupil circumference occupied by opacity. For this analysis,
N&NBn( cortical cataract was defined as 4/16 or greater opacity,
eWcqf/4?" PSC cataract was defined as opacity equal to or greater than
4k;FZo]S 1 mm2 and nuclear cataract was defined as opacity equal to
&u.{]Yjx or greater than Wilmer standard 2,12 independent of visual
<?nI O acuity. Examples of the minimum opacities defined as cortical,
Y<xqws nuclear and PSC cataract are presented in Figure 1.
UphTMyn3 Bilateral congenital cataracts or cataracts secondary to
DXiA4ihr= intraocular inflammation or trauma were excluded from the
m^D'p analysis. Two cases of bilateral secondary cataract and eight
e xb}
y cases of bilateral congenital cataract were excluded from the
pLB2! + analyses.
egaX[j r A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
:jiuu@< Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
Sa= tiOv height set to an incident angle of 30° was used for examinations.
G(&[1V % x Ektachrome® 200 ASA colour slide film (Eastman
0\dmp'j] Kodak Company, Rochester, NY, USA) was used to photograph
l_^OdQ9D the nuclear opacities. The cortical opacities were
E]@&<TFq photographed with an Oxford® retroillumination camera
u\*9\G (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
UBaXS_c\ film (Eastman Kodak). Photographs were graded separately
A[Mke by two research assistants and discrepancies were adjudicated
z#tIa by an independent reviewer. Any discrepancies
YN8x|DLi? between the clinical grades and the photograph grades were
U]3!"+Y1P resolved. Except in cases where photographs were missing,
L`+[mX&2B the photograph grades were used in the analyses. Photograph
],]Rv#` grades were available for 4301 (84%) for cortical
pR
S! cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
-r\jIO_ for PSC cataract. Cataract status was classified according to
6 4_}"fU the severity of the opacity in the worse eye.
#1<m\z 7l Assessment of risk factors
gu
k,GF9p] A standardized questionnaire was used to obtain information
\dk1a about education, employment and ethnic background.11
hfwJZ\_60 Specific information was elicited on the occurrence, duration
W:r[o%B and treatment of a number of medical conditions,
WcN
4ff- including ocular trauma, arthritis, diabetes, gout, hypertension
S2$E`'
J and mental illness. Information about the use, dose and
pv]@}+<Dt duration of tobacco, alcohol, analgesics and steriods were
;(NTzBq!1 collected, and a food frequency questionnaire was used to
'LYDJ~ determine current consumption of dietary sources of antioxidants
'.|} and use of vitamin supplements.
lx`?n<-X Data management and statistical analysis
SyL"Bmi Data were collected either by direct computer entry with a
O/~T+T% questionnaire programmed in Paradox© (Carel Corporation,
b^W&-Hh Ottawa, Canada) with internal consistency checks, or
.eJKIck on self-coding forms. Open-ended responses were coded at
K$S0h-?9]O a later time. Data that were entered on the self-coded forms
c~T{; were entered into a computer with double data entry and
392V\qtS reconciliation of any inconsistencies. Data range and consistency
wkt4vE87 checks were performed on the entire data set.
x^y$ pr SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
A;Uc&G employed for statistical analyses.
#aqnj+ Ninety-five per cent confidence limits around the agespecific
BbB3#/g rates were calculated according to Cochran13 to
<$nPGz)} account for the effect of the cluster sampling. Ninety-five
3U6QYD55]] per cent confidence limits around age-standardized rates
A+/Lt>+AS were calculated according to Breslow and Day.14 The strataspecific
Z_ElLY data were weighted according to the 1996
u$w.'lK Australian Bureau of Statistics census data15 to reflect the
R&uPoY,f cataract prevalence in the entire Victorian population.
+C=vuR Univariate analyses with Student’s t-tests and chi-squared
0hS&4nW tests were first employed to evaluate risk factors for unoperated
xbiprhdv cataract. Any factors with P < 0.10 were then fitted
B}
qRz into a backwards stepwise logistic regression model. For the
.r/s.g Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
v=^^Mr"Z^ final multivariate models, P < 0.05 was considered statistically
GVT 6cR significant. Design effect was assessed through the use
uNf'Zeo of cluster-specific models and multivariate models. The
(0`rfYv5.R design effect was assumed to be additive and an adjustment
Qe~C}j% made in the variance by adding the variance associated with
2K~v`c*4 the design effect prior to constructing the 95% confidence
ceg\lE:8 limits.
?3DL .U{ RESULTS
0,0WdJAe Study population
DvW
Bvs, A total of 3271 (83%) of the Melbourne residents, 403
2-S}#S}2C (90%) Melbourne nursing home residents, and 1473 (92%)
Va[&~lA) rural residents participated. In general, non-participants did
"4XjABJ4' not differ from participants.16 The study population was
# l1*# Z representative of the Victorian population and Australia as
,,FhE a whole.
Ds=d~sN u The Melbourne residents ranged in age from 40 to
a aVq>$G3 98 years (mean = 59) and 1511 (46%) were male. The
P w6l' Melbourne nursing home residents ranged in age from 46 to
D[T\
_3W 101 years (mean = 82) and 85 (21%) were men. The rural
,-])[
u residents ranged in age from 40 to 103 years (mean = 60)
oKRI2ni$j9 and 701 (47.5%) were men.
*4 m]UK Prevalence of cataract and prior cataract surgery
axG%@5 As would be expected, the rate of any cataract increases
1%@i4 dramatically with age (Table 1). The weighted rate of any
"<oR.f=0 cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
o &b\bK%E Although the rates varied somewhat between the three
Kj"n
Id) strata, they were not significantly different as the 95% confidence
sVO|Ghy65 limits overlapped. The per cent of cataractous eyes
QIwO _[Q with best-corrected visual acuity of less than 6/12 was 12.5%
{s@&3i?ZiC (65/520) for cortical cataract, 18% for nuclear cataract
D<Z\6)|%I (97/534) and 14.4% (27/187) for PSC cataract. Cataract
@&h_+|:- surgery also rose dramatically with age. The overall
\KEmfCx'n weighted rate of prior cataract surgery in Victoria was
zll?/|% 3.79% (95% CL 2.97, 4.60) (Table 2).
5"#xbvRS0H Risk factors for unoperated cataract
nQw, /Lk Cases of cataract that had not been removed were classified
AWZ4h,as{ as unoperated cataract. Risk factor analyses for unoperated
Ud-c+, xX cataract were not performed with the nursing home residents
[c>YKN2qa as information about risk factor exposure was not
,=6;dT available for this cohort. The following factors were assessed
uN&49o in relation to unoperated cataract: age, sex, residence
P\X$fD (urban/rural), language spoken at home (a measure of ethnic
B3u:D"t integration), country of birth, parents’ country of birth (a
*xKY>E+ measure of ethnicity), years since migration, education, use
E-rGOm" m of ophthalmic services, use of optometric services, private
xqVIw!J?/} health insurance status, duration of distance glasses use,
H|N,nkhH} glaucoma, age-related maculopathy and employment status.
X{5(i3?S In this cross sectional study it was not possible to assess the
CIt@xi#I level of visual acuity that would predict a patient’s having
7baQ4QY?n cataract surgery, as visual acuity data prior to cataract
CwzDkr&QC_ surgery were not available.
6$+F5T The significant risk factors for unoperated cataract in univariate
/vPcg analyses were related to: whether a participant had
^paM{'J\\) ever seen an optometrist, seen an ophthalmologist or been
^X?3e1om diagnosed with glaucoma; and participants’ employment
"Kn%|\YL@4 status (currently employed) and age. These significant
X04JQLhy" factors were placed in a backwards stepwise logistic regression
8z"*CJ@ model. The factors that remained significantly related
~LN
{5zg to unoperated cataract were whether participants had ever
a^GJR]]
{ seen an ophthalmologist, seen an optometrist and been
=I9RM9O< diagnosed with glaucoma. None of the demographic factors
}Ias7d?re were associated with unoperated cataract in the multivariate
OM7EmMa; model.
64-;| k4F The per cent of participants with unoperated cataract
@ * *]o who said that they were dissatisfied or very dissatisfied with
vq
JjAls Operated and unoperated cataract in Australia 79
kEM|;&=_ Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
z0-`D.D@\ Age group Sex Urban Rural Nursing home Weighted total
[E|% (years) (%) (%) (%)
LYyOcb[x 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
C.;H?So( Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
3rw<#t;v 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
;sn]Blpq Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
dBMr%6tz 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
"_T8Km008 Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
+(3U_]Lu 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
Z]1jg>") Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
f&
>[$zh 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
Gg=Y}S7: Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
S
7 *LV; 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
\bPSy0 Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
Wc
q
UF"A Age-standardized
E1-BB (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)
TmIw?#q^ aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
?m>!
P@
M their current vision was 30% (290/683), compared with 27%
m]#oZVngy (26/95) of participants with prior cataract surgery (chisquared,
qTUyax 1 d.f. = 0.25, P = 0.62).
HJeZm Outcomes of cataract surgery
#.^A5`k Two hundred and forty-nine eyes had undergone prior
ic(`E v cataract surgery. Of these 249 operated eyes, 49 (20%) were
(B:+md\Q left aphakic, 6 (2.4%) had anterior chamber intraocular
85GU~. lenses and 194 (78%) had posterior chamber intraocular
K{WLo5HP lenses. The rate of capsulotomy in the eyes with intact
4V9S~^v| posterior capsules was 36% (73/202). Fifteen per cent of
6./3w&D; eyes (17/114) with a clear posterior capsule had bestcorrected
T>2_ r6; visual acuity of less than 6/12 compared with 43%
waI:w, of eyes (6/14) with opaque capsules, and 15% of eyes
e;G}T%W (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
Yg kd 1uI. P = 0.027).
vlS+UFH0 The percentage of eyes with best-corrected visual acuity
b>Em~NMu_ of 6/12 or better was 96% (302/314) for eyes without
bs9X4n5 cataract, 88% (1417/1609) for eyes with prevalent cataract
8.m9 =+)8 and 85% (211/249) for eyes with operated cataract (chisquared,
f\U(7)2 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
#M~6A^) operated eyes (11%) had visual acuities of less than 6/18
UHT2a9rG (moderate vision impairment) (Fig. 2). A cause of this
\\UOpl moderate visual impairment (but not the only cause) in four
a
0+W-#G (15%) eyes was secondary to cataract surgery. Three of these
3F ]30 four eyes had undergone intracapsular cataract extraction
DO{Lj#@ and the fourth eye had an opaque posterior capsule. No one
f~?4 had bilateral vision impairment as a result of their cataract
+Cg[!6[# surgery.
%-J}m DISCUSSION
)N'rYS'9 To our knowledge, this is the first paper to systematically
PyQ
P K, assess the prevalence of current cataract, previous cataract
* ,#SwZ surgery, predictors of unoperated cataract and the outcomes
' |Ia-RbX of cataract surgery in a population-based sample. The Visual
mP[Z lS~" Impairment Project is unique in that the sampling frame and
NPjNkpWm&= high response rate have ensured that the study population is
'S#D+oF(1~ representative of Australians aged 40 years and over. Therefore,
f)#rBAkt these data can be used to plan age-related cataract
|B~^7RHXo
services throughout Australia.
Xn= We found the rate of any cataract in those over the age
s
)9d\{ of 40 years to be 22%. Although relatively high, this rate is
Bh
,GQHJ significantly less than was reported in a number of previous
bBg=X}9 studies,2,4,6 with the exception of the Casteldaccia Eye
Cr>YpWm Study.5 However, it is difficult to compare rates of cataract
*w5xC5* between studies because of different methodologies and
y)uxj-G cataract definitions employed in the various studies, as well
o_R_ as the different age structures of the study populations.
ZWXA%u7V Other studies have used less conservative definitions of
8d1r#sILI cataract, thus leading to higher rates of cataract as defined.
ESi'3mbeC In most large epidemiologic studies of cataract, visual acuity
?M9?GodbP. has not been included in the definition of cataract.
HIsB)W&%@ Therefore, the prevalence of cataract may not reflect the
K.r
"KxCm| actual need for cataract surgery in the community.
J7FzOwd1h 80 McCarty et al.
UiQF4Uc" Table 2. Prevalence of previous cataract by age, gender and cohort
[oDu3Qn Age group Gender Urban Rural Nursing home Weighted total
Y>J u$i (years) (%) (%) (%)
Bv{DZ?{s 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
u#)ARCx ,w Female 0.00 0.00 0.00 0.00 (
;/
ASl<t, 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
a?1Ml>R6P Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
vM?jm!nd 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
5ggsOqH Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
w^E$R 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
p5`={'>- Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
P-?R\(QYtR 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
TrR=3_;.7 Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
K+3+?oYKH 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
"@(Sw>*o Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
K;l
xPM] Age-standardized
pSdtAv (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)
-)9aY. Figure 2. Visual acuity in eyes that had undergone cataract
cceh`s=cU surgery, n = 249. h, Presenting; j, best-corrected.
:wY(</H Operated and unoperated cataract in Australia 81
|Ng}ZLBM The weighted prevalence of prior cataract surgery in the
nO
`R++ Visual Impairment Project (3.6%) was similar to the crude
")i_{C,b^ rate in the Beaver Dam Eye Study4 (3.1%), but less than the
x:iLBYf crude rate in the Blue Mountains Eye Study6 (6.0%).
n+D93d9LP However, the age-standardized rate in the Blue Mountains
;(
[^+_/ Eye Study (standardized to the age distribution of the urban
D]?yGI_ Visual Impairment Project cohort) was found to be less than
1eOQ;#O
V the Visual Impairment Project (standardized rate = 1.36%,
#n.XOet<\ 95% CL 1.25, 1.47). The incidence of cataract surgery in
->)0jZax Australia has exceeded population growth.1 This is due,
j7yUya& perhaps, to advances in surgical techniques and lens
NeR1}W implants that have changed the risk–benefit ratio.
`%_(_%K The Global Initiative for the Elimination of Avoidable
K$c?:?wmo Blindness, sponsored by the World Health Organization,
ODKHI\U
states that cataract surgical services should be provided that
n'83P%x ‘have a high success rate in terms of visual outcome and
<lP5}F87 improved quality of life’,17 although the ‘high success rate’ is
KZ 4G" not defined. Population- and clinic-based studies conducted
G]T&{3g-. in the United States have demonstrated marked improvement
7`HKa@ in visual acuity following cataract surgery.18–20 We
JZ)w found that 85% of eyes that had undergone cataract extraction
Ww
=ksggpB had visual acuity of 6/12 or better. Previously, we have
]SUW"5L- shown that participants with prevalent cataract in this
/>O.U? cohort are more likely to express dissatisfaction with their
Lklb current vision than participants without cataract or participants
WDF6.i ? with prior cataract surgery.21 In a national study in the
-IS$1 United States, researchers found that the change in patients’
;R7+6 ratings of their vision difficulties and satisfaction with their
y4,t=Gq7^ vision after cataract surgery were more highly related to
zKFiCP
K their change in visual functioning score than to their change
VLC=>w\, in visual acuity.19 Furthermore, improvement in visual function
rTzXRMv@o has been shown to be associated with improvement in
>S@><[C overall quality of life.22
K_-S`-eH A recent review found that the incidence of visually
+T HBPEq significant posterior capsule opacification following
X4/3
vY cataract surgery to be greater than 25%.23 We found 36%
y<m}dW6[\ capsulotomy in our population and that this was associated
bdj')%@n with visual acuity similar to that of eyes with a clear
oT- Y capsule, but significantly better than that of eyes with an
NW~`oc)NS opaque capsule.
t8uaNvUM}e A number of studies have shown that the demand and
$u,
~183 timing of cataract surgery vary according to visual acuity,
!=]cAS
PGD degree of handicap and socioeconomic factors.8–10,24,25 We
*/j[n$K>~` have also shown previously that ophthalmologists are more
5
~Y a Xh^ likely to refer a patient for cataract surgery if the patient is
ad`7[fI employed and less likely to refer a nursing home resident.7
?zK\!r{ In the Visual Impairment Project, we did not find that any
qjH/E6GGg particular subgroup of the population was at greater risk of
\i
As having unoperated cataract. Universal access to health care
j=Z;M1 in Australia may explain the fact that people without
nxs'qX(D Medicare are more likely to delay cataract operations in the
D YTC2 USA,8 but not having private health insurance is not associated
y)T|1) with unoperated cataract in Australia.
CUx[LZR7m In summary, cataract is a significant public health problem
Q\aC:68
in that one in four people in their 80s will have had cataract
3u4P
[ surgery. The importance of age-related cataract surgery will
Ha~}NO increase further with the ageing of the population: the
R?8/qGSVqJ number of people over age 60 years is expected to double in
?:#$btmn? the next 20 years. Cataract surgery services are well
-fD W>]_ accessed by the Victorian population and the visual outcomes
]EEac of cataract surgery have been shown to be very good.
\8]("l}ms8 These data can be used to plan for age-related cataract
}h=3[pe} surgical services in Australia in the future as the need for
Nh+Xlg
XG cataract extractions increases.
O[R
ACKNOWLEDGEMENTS
[ip}f4K The Visual Impairment Project was funded in part by grants
J:0`*7 from the Victorian Health Promotion Foundation, the
a
t%qowt National Health and Medical Research Council, the Ansell
9Qn*frdY, Ophthalmology Foundation, the Dorothy Edols Estate and
6 IKi*} the Jack Brockhoff Foundation. Dr McCarty is the recipient
goc"+K of a Wagstaff Fellowship in Ophthalmology from the Royal
_q`f5*Z[ Victorian Eye and Ear Hospital.
jNW/Biy4u REFERENCES
]9~6lx3/ 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
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