ABSTRACT
oOLA&N-A~ Purpose: To quantify the prevalence of cataract, the outcomes
\o3s&{+y, of cataract surgery and the factors related to
b
ivo7_ unoperated cataract in Australia.
$FIJI^Kd7 Methods: Participants were recruited from the Visual
]9'F<T= $_ Impairment Project: a cluster, stratified sample of more than
{
R[ V 5000 Victorians aged 40 years and over. At examination
=h=-&DSA sites interviews, clinical examinations and lens photography
zVe,HKF/ were performed. Cataract was defined in participants who
hH-!3S2' had: had previous cataract surgery, cortical cataract greater
Q>;Aq!mr= than 4/16, nuclear greater than Wilmer standard 2, or
zL50|U0H posterior subcapsular greater than 1 mm2.
Yt:%)&50}- Results: The participant group comprised 3271 Melbourne
)k[XO residents, 403 Melbourne nursing home residents and 1473
X}h}3+V rural residents.The weighted rate of any cataract in Victoria
|F'eT
4 was 21.5%. The overall weighted rate of prior cataract
=>Z4vWX* surgery was 3.79%. Two hundred and forty-nine eyes had
Uvi@HB HJ had prior cataract surgery. Of these 249 procedures, 49
SX =^C (20%) were aphakic, 6 (2.4%) had anterior chamber
H15!QxD# intraocular lenses and 194 (78%) had posterior chamber
Bd;EI)JT intraocular lenses.Two hundred and eleven of these operated
,,IK} eyes (85%) had best-corrected visual acuity of 6/12 or
x
0vW9*& better, the legal requirement for a driver’s license.Twentyseven
|
pU>^ (11%) had visual acuity of less than 6/18 (moderate
z5<&}Vh;P vision impairment). Complications of cataract surgery
A] o3MoSt caused reduced vision in four of the 27 eyes (15%), or 1.9%
{\VsM#K6 of operated eyes. Three of these four eyes had undergone
i*09m^r intracapsular cataract extraction and the fourth eye had an
+:c}LCI9< opaque posterior capsule. No one had bilateral vision
eUgKwu; impairment as a result of cataract surgery. Surprisingly, no
6/(Z*L"~6k particular demographic factors (such as age, gender, rural
>%_i#|dE> residence, occupation, employment status, health insurance
CJ#Yu3} status, ethnicity) were related to the presence of unoperated
la]Zk cataract.
eD^(*a>( Conclusions: Although the overall prevalence of cataract is
RzLe
R%O quite high, no particular subgroup is systematically underserviced
:
9zEne4 in terms of cataract surgery. Overall, the results of
*s2 C+@ef cataract surgery are very good, with the majority of eyes
=)Goip achieving driving vision following cataract extraction.
j{/wG:: Key words: cataract extraction, health planning, health
:ZM=P3QZ services accessibility, prevalence
+J}h INTRODUCTION
%.{xo.`a[ Cataract is the leading cause of blindness worldwide and, in
:{Iv
]d Australia, cataract extractions account for the majority of all
Ftud6 ophthalmic procedures.1 Over the period 1985–94, the rate
pSpxd|k of cataract surgery in Australia was twice as high as would be
K*j1Fy: expected from the growth in the elderly population.1
zn\$6'" Although there have been a number of studies reporting
6". v6 the prevalence of cataract in various populations,2–6 there is
EixAmG little information about determinants of cataract surgery in
6b4]dvl_ the population. A previous survey of Australian ophthalmologists
x&FBh!5H showed that patient concern and lifestyle, rather
\3j4=K'nE than visual acuity itself, are the primary factors for referral
@#5
?tk0 for cataract surgery.7 This supports prior research which has
FWyfFCK shown that visual acuity is not a strong predictor of need for
9z?B@;lMc cataract surgery.8,9 Elsewhere, socioeconomic status has
bLz('mUY been shown to be related to cataract surgery rates.10
uF-Rl##
> To appropriately plan health care services, information is
62/tg*) needed about the prevalence of age-related cataract in the
yrrP#F community as well as the factors associated with cataract
xa%2w] surgery. The purpose of this study is to quantify the prevalence
x[YW 3nF of any cataract in Australia, to describe the factors
t-J\j"~%+ related to unoperated cataract in the community and to
}cI _$ describe the visual outcomes of cataract surgery.
zLV k7u{e METHODS
+0n,>eDjg^ Study population
At8^yF
Details about the study methodology for the Visual
>zcp(M98 Impairment Project have been published previously.11
0]t7(P"F6 Briefly, cluster sampling within three strata was employed to
ltG|#( recruit subjects aged 40 years and over to participate.
1?ST*b Within the Melbourne Statistical Division, nine pairs of
I~U;M+n*y census collector districts were randomly selected. Fourteen
%;tBWyq}_ nursing homes within a 5 km radius of these nine test sites
e{IwFX were randomly chosen to recruit nursing home residents.
J
k FZd Clinical and Experimental Ophthalmology (2000) 28, 77–82
ln=:E$jX Original Article
UNKXfe(X9 Operated and unoperated cataract in Australia
F%e5j9X` Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
&GLe4zEh Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
U10:@Wzh n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
}VXZM7@u Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au
PsoW:t 78 McCarty et al.
N'RUtFqj Finally, four pairs of census collector districts in four rural
Ewczq1%l: Victorian communities were randomly selected to recruit rural
:l?/]K residents. A household census was conducted to identify
u}IQ)Ma eligible residents aged 40 years and over who had been a
BpZ17"\z resident at that address for at least 6 months. At the time of
p3z%Y$!Tm the household census, basic information about age, sex,
q| 7$@H^* country of birth, language spoken at home, education, use of
QDJ:LJz\ corrective spectacles and use of eye care services was collected.
)A
a
h Eligible residents were then invited to attend a local
AwO'%+Bv examination site for a more detailed interview and examination.
-axV;+"b The study protocol was approved by the Royal Victorian
Y!L<&
sl Eye and Ear Hospital Human Research Ethics Committee.
E'4dI: Assessment of cataract
b_j8g{/9 A standardized ophthalmic examination was performed after
5Dlx]_ pupil dilatation with one drop of 10% phenylephrine
h|t\rV^ hydrochloride. Lens opacities were graded clinically at the
^5d9n<_xnQ time of the examination and subsequently from photos using
+zn207.` the Wilmer cataract photo-grading system.12 Cortical and
bv8GJ # posterior subcapsular (PSC) opacities were assessed on
&24z`ZS[w6 retroillumination and measured as the proportion (in 1/16)
%R[X_n= of pupil circumference occupied by opacity. For this analysis,
gR:21*&cz cortical cataract was defined as 4/16 or greater opacity,
R~&i8n. PSC cataract was defined as opacity equal to or greater than
`OmYz{*r 1 mm2 and nuclear cataract was defined as opacity equal to
P",E/beV or greater than Wilmer standard 2,12 independent of visual
IB+)2 ` acuity. Examples of the minimum opacities defined as cortical,
nzK"eNDN. nuclear and PSC cataract are presented in Figure 1.
:},/D*v Bilateral congenital cataracts or cataracts secondary to
&k2nt intraocular inflammation or trauma were excluded from the
Tx'ctd#Y analysis. Two cases of bilateral secondary cataract and eight
h8lI#Gs cases of bilateral congenital cataract were excluded from the
B 8ycr~ analyses.
J6Q}a7I# A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
az2CFd^
M Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
:'LG%E:b height set to an incident angle of 30° was used for examinations.
xz$S5tgDQK Ektachrome® 200 ASA colour slide film (Eastman
@j Y_^8#S Kodak Company, Rochester, NY, USA) was used to photograph
WaRYrTDv64 the nuclear opacities. The cortical opacities were
Z/ypWoV( photographed with an Oxford® retroillumination camera
cOr@dUSL (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
32sb$|eQq film (Eastman Kodak). Photographs were graded separately
4{r_EV[( by two research assistants and discrepancies were adjudicated
$iblLZhj by an independent reviewer. Any discrepancies
!7K-Kqn between the clinical grades and the photograph grades were
tyLR_@i%% resolved. Except in cases where photographs were missing,
r2*'5jk_ the photograph grades were used in the analyses. Photograph
/B?hM&@z grades were available for 4301 (84%) for cortical
[}OL@num cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
j;k(AM< for PSC cataract. Cataract status was classified according to
Tcglt>tj" the severity of the opacity in the worse eye.
V!SB9t`E Assessment of risk factors
/e5Fx A standardized questionnaire was used to obtain information
n>dM OQb about education, employment and ethnic background.11
2ju1<t,8) Specific information was elicited on the occurrence, duration
D^Z~>D6 and treatment of a number of medical conditions,
+(3PY e\ including ocular trauma, arthritis, diabetes, gout, hypertension
TLL.Ch|#Y and mental illness. Information about the use, dose and
o^Y'e+T" duration of tobacco, alcohol, analgesics and steriods were
'7F`qL\/#( collected, and a food frequency questionnaire was used to
f-\l<o( determine current consumption of dietary sources of antioxidants
(!'; and use of vitamin supplements.
_OF8D Data management and statistical analysis
~X;(m<f2 Data were collected either by direct computer entry with a
n^/,>7J questionnaire programmed in Paradox© (Carel Corporation,
d]e`t"Aj Ottawa, Canada) with internal consistency checks, or
X/1Z9a+W on self-coding forms. Open-ended responses were coded at
@T1>%oi a later time. Data that were entered on the self-coded forms
)^!-Aj\x were entered into a computer with double data entry and
<,0&Ox reconciliation of any inconsistencies. Data range and consistency
eT+MN` checks were performed on the entire data set.
RWBmQg^]X SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
LFSOHJj employed for statistical analyses.
zck)D^,aO Ninety-five per cent confidence limits around the agespecific
[jumq1 rates were calculated according to Cochran13 to
T6H"ER$ account for the effect of the cluster sampling. Ninety-five
7k3":2: per cent confidence limits around age-standardized rates
V!KtF were calculated according to Breslow and Day.14 The strataspecific
c2"eq2'BS data were weighted according to the 1996
%
wRJ"T`Tt Australian Bureau of Statistics census data15 to reflect the
of& vQ cataract prevalence in the entire Victorian population.
dm$:xE": Univariate analyses with Student’s t-tests and chi-squared
v2@M,xbxF: tests were first employed to evaluate risk factors for unoperated
C-6+ZIk4 cataract. Any factors with P < 0.10 were then fitted
*pasI.2s# into a backwards stepwise logistic regression model. For the
N&>D/Z;" Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
\iVYhl final multivariate models, P < 0.05 was considered statistically
C1G Wi4) significant. Design effect was assessed through the use
DTIy/ of cluster-specific models and multivariate models. The
t%dPj8~ design effect was assumed to be additive and an adjustment
*/8\Z46z made in the variance by adding the variance associated with
&(.ZHF the design effect prior to constructing the 95% confidence
9) YG)A~< limits.
V
u!,tpa. RESULTS
Y2$%%@ Study population
2dI:],7 A total of 3271 (83%) of the Melbourne residents, 403
lMO0d_:b1 (90%) Melbourne nursing home residents, and 1473 (92%)
mA>Pr<aV: rural residents participated. In general, non-participants did
1%=,J'AH not differ from participants.16 The study population was
A qm0|GlJ representative of the Victorian population and Australia as
L]tyL) a whole.
z`_N|iEd The Melbourne residents ranged in age from 40 to
H
5aUZ= 98 years (mean = 59) and 1511 (46%) were male. The
`H|g~7KD& Melbourne nursing home residents ranged in age from 46 to
eeX)JC0A 101 years (mean = 82) and 85 (21%) were men. The rural
w\QpQ~OX residents ranged in age from 40 to 103 years (mean = 60)
{l1;&y? and 701 (47.5%) were men.
`150$*K&B Prevalence of cataract and prior cataract surgery
l:[=M:#p As would be expected, the rate of any cataract increases
;}PL/L$L6; dramatically with age (Table 1). The weighted rate of any
bIhL!Ty T. cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
RcE%?2lD Although the rates varied somewhat between the three
lwB!ti strata, they were not significantly different as the 95% confidence
/za,&7sf limits overlapped. The per cent of cataractous eyes
WgL!@g with best-corrected visual acuity of less than 6/12 was 12.5%
~& l`" (65/520) for cortical cataract, 18% for nuclear cataract
1hN!
2Y: (97/534) and 14.4% (27/187) for PSC cataract. Cataract
ls5S9R 5 surgery also rose dramatically with age. The overall
_\<M58/z weighted rate of prior cataract surgery in Victoria was
g$97"d' 3.79% (95% CL 2.97, 4.60) (Table 2).
=sm(Z;" Risk factors for unoperated cataract
AX)zSr Xn Cases of cataract that had not been removed were classified
$OO[C={v[ as unoperated cataract. Risk factor analyses for unoperated
yqU++;6 cataract were not performed with the nursing home residents
v$c D!`+k as information about risk factor exposure was not
3m^BYr*y^ available for this cohort. The following factors were assessed
L9.#/%I\ in relation to unoperated cataract: age, sex, residence
hG67%T'}A (urban/rural), language spoken at home (a measure of ethnic
QJ/SP integration), country of birth, parents’ country of birth (a
Cr
`
0C measure of ethnicity), years since migration, education, use
PX
'LN of ophthalmic services, use of optometric services, private
a !IH-XJ2 health insurance status, duration of distance glasses use,
j.6kjQN glaucoma, age-related maculopathy and employment status.
xEBjfn In this cross sectional study it was not possible to assess the
(gZ!
o_ level of visual acuity that would predict a patient’s having
1mX*0> cataract surgery, as visual acuity data prior to cataract
0D'Wr(U( surgery were not available.
J-}NFWR;t The significant risk factors for unoperated cataract in univariate
VC.?]'OqD analyses were related to: whether a participant had
WdT|xf.Q& ever seen an optometrist, seen an ophthalmologist or been
vf2K2\fn diagnosed with glaucoma; and participants’ employment
!r|X
6`g status (currently employed) and age. These significant
ueR42J%s factors were placed in a backwards stepwise logistic regression
&Yg/08* model. The factors that remained significantly related
z m'jk D|
to unoperated cataract were whether participants had ever
z'lNO| nU seen an ophthalmologist, seen an optometrist and been
Bu1z$#AC diagnosed with glaucoma. None of the demographic factors
f[IchCwX were associated with unoperated cataract in the multivariate
]lU
u%<-; model.
ZkW@ |v
The per cent of participants with unoperated cataract
=@2V#X]M* who said that they were dissatisfied or very dissatisfied with
d<'xpdxc Operated and unoperated cataract in Australia 79
Q7|13^|C Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
S F>D:$a Age group Sex Urban Rural Nursing home Weighted total
O@iW?9C+ (years) (%) (%) (%)
j;)g+9` 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
>
A&@W p1 Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
yf) `jPM1< 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
0>iFXw:fn Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
U[b;#Y1X 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
(x
qA.(F Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
\w^QHX1+ 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
2HXKz7da Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
K;[%S 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
f_ztnRw Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
hyiMOa 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
.KucjRI Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
"<x~{BN? Age-standardized
hFMst%:y$ (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)
ulf/C%t,R aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
ex\W]5 their current vision was 30% (290/683), compared with 27%
T[-c| (26/95) of participants with prior cataract surgery (chisquared,
W@,p9=425 1 d.f. = 0.25, P = 0.62).
]TgP!M&q Outcomes of cataract surgery
=`~Z@IbdI Two hundred and forty-nine eyes had undergone prior
{|Ki^8 h/p cataract surgery. Of these 249 operated eyes, 49 (20%) were
cEc,eq| left aphakic, 6 (2.4%) had anterior chamber intraocular
P4j 8`}&/ lenses and 194 (78%) had posterior chamber intraocular
S tnv> lenses. The rate of capsulotomy in the eyes with intact
T_?nd T2 posterior capsules was 36% (73/202). Fifteen per cent of
HDVl5X`j' eyes (17/114) with a clear posterior capsule had bestcorrected
d:hL
)x visual acuity of less than 6/12 compared with 43%
NOr
<, of eyes (6/14) with opaque capsules, and 15% of eyes
^qO=~U!{ (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
rEyz|k: P = 0.027).
\c~{o+UD- The percentage of eyes with best-corrected visual acuity
,p!B"#
ot of 6/12 or better was 96% (302/314) for eyes without
F|?'9s*;6G cataract, 88% (1417/1609) for eyes with prevalent cataract
pp]_/46nN and 85% (211/249) for eyes with operated cataract (chisquared,
pzq;vMr 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
LxlbD#<V operated eyes (11%) had visual acuities of less than 6/18
Sf&?3a+f (moderate vision impairment) (Fig. 2). A cause of this
XDkS
^9 moderate visual impairment (but not the only cause) in four
%gu
$_S (15%) eyes was secondary to cataract surgery. Three of these
AB"1(PbG four eyes had undergone intracapsular cataract extraction
AL]h|)6QpC and the fourth eye had an opaque posterior capsule. No one
'Z.OF5|eGT had bilateral vision impairment as a result of their cataract
v0`qMBr1y surgery.
:,NFFN DISCUSSION
qA/#IUi)1 To our knowledge, this is the first paper to systematically
/
e|[SITe assess the prevalence of current cataract, previous cataract
HX3D*2v": surgery, predictors of unoperated cataract and the outcomes
`M?v!]o of cataract surgery in a population-based sample. The Visual
i)7n c Impairment Project is unique in that the sampling frame and
>X[|c"l. high response rate have ensured that the study population is
G;C8Kde representative of Australians aged 40 years and over. Therefore,
}A1|jY)x these data can be used to plan age-related cataract
@%OPy|=,{ services throughout Australia.
"($Lx We found the rate of any cataract in those over the age
\[hn]@@ of 40 years to be 22%. Although relatively high, this rate is
UU iNR significantly less than was reported in a number of previous
F1gt3 a
e studies,2,4,6 with the exception of the Casteldaccia Eye
\fK47oV Study.5 However, it is difficult to compare rates of cataract
GS
;HtUQ between studies because of different methodologies and
g.I(WJX0 cataract definitions employed in the various studies, as well
.[T'yc:= as the different age structures of the study populations.
17>5#JLP
Other studies have used less conservative definitions of
Nfv="t9e cataract, thus leading to higher rates of cataract as defined.
$!!R:Wn/R In most large epidemiologic studies of cataract, visual acuity
U/ ?F:QD4 has not been included in the definition of cataract.
UT3bd,, Therefore, the prevalence of cataract may not reflect the
"\}b!gl$8 actual need for cataract surgery in the community.
GI4?|@%vD! 80 McCarty et al.
\V]t!mZ-}l Table 2. Prevalence of previous cataract by age, gender and cohort
i<%m Iq1L Age group Gender Urban Rural Nursing home Weighted total
Da-u-_~ (years) (%) (%) (%)
O!;H}{[dg 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
'gCJ[ ce Female 0.00 0.00 0.00 0.00 (
'%R<" 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
qQ^d9EK'?~ Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
v@VLVf)>9^ 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
&x`&03X Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
>K\3*]>J3 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
dUIqD l Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
Cl,9yU)1n 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
)1WMlG Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
w&%9IJ 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
iC\%_5/_ Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
le.anJAr Age-standardized
Z:!IX^q;}n (95% CL) Combined 3.31 (2.70, 3.93) 4.36 (2.67, 6.06) 2.26 (0.82, 3.70) 3.79 (2.97, 4.60)
<Z},A-\
S* Figure 2. Visual acuity in eyes that had undergone cataract
`?l3Ct* surgery, n = 249. h, Presenting; j, best-corrected.
c&E]E( Operated and unoperated cataract in Australia 81
1B 5:s,Oyj The weighted prevalence of prior cataract surgery in the
2HD:JdL Visual Impairment Project (3.6%) was similar to the crude
%,0%NjK
rate in the Beaver Dam Eye Study4 (3.1%), but less than the
YxXqI crude rate in the Blue Mountains Eye Study6 (6.0%).
U9
#w However, the age-standardized rate in the Blue Mountains
EkjgNEXq Eye Study (standardized to the age distribution of the urban
uAUp5XP|Z Visual Impairment Project cohort) was found to be less than
28a$NP\KW the Visual Impairment Project (standardized rate = 1.36%,
8] `Ru5nd 95% CL 1.25, 1.47). The incidence of cataract surgery in
kO1}?dWpa Australia has exceeded population growth.1 This is due,
eNbpwne perhaps, to advances in surgical techniques and lens
[KSH~:h:NR implants that have changed the risk–benefit ratio.
,beS0U] The Global Initiative for the Elimination of Avoidable
49AW6H.JT Blindness, sponsored by the World Health Organization,
7/aOsW"6 states that cataract surgical services should be provided that
S( ‘have a high success rate in terms of visual outcome and
x:fW~!Xc6 improved quality of life’,17 although the ‘high success rate’ is
a7#?h%wf not defined. Population- and clinic-based studies conducted
Od
##U6e` in the United States have demonstrated marked improvement
Ab2Q
\+, in visual acuity following cataract surgery.18–20 We
KnGTcoXg_ found that 85% of eyes that had undergone cataract extraction
H; Ku
w had visual acuity of 6/12 or better. Previously, we have
~E)fpGJ shown that participants with prevalent cataract in this
eM2|c3/ cohort are more likely to express dissatisfaction with their
B$XwTJ> current vision than participants without cataract or participants
V
kjuyK with prior cataract surgery.21 In a national study in the
y t5H oy United States, researchers found that the change in patients’
yCP4r6X0 ratings of their vision difficulties and satisfaction with their
, jU5|2 vision after cataract surgery were more highly related to
*2e!M^K< their change in visual functioning score than to their change
O"Q7
Rx in visual acuity.19 Furthermore, improvement in visual function
V 1/p_)A has been shown to be associated with improvement in
fQdK]rLj overall quality of life.22
\)/yC74r7( A recent review found that the incidence of visually
y >+mc7n significant posterior capsule opacification following
/.1.MssQM cataract surgery to be greater than 25%.23 We found 36%
,|h)bg7. capsulotomy in our population and that this was associated
U*)m', with visual acuity similar to that of eyes with a clear
Bd~1P/ capsule, but significantly better than that of eyes with an
=1.9/hW opaque capsule.
y*23$fj( A number of studies have shown that the demand and
:j^FJ@2_ timing of cataract surgery vary according to visual acuity,
fo0+dzazY degree of handicap and socioeconomic factors.8–10,24,25 We
~1L:_Sg* have also shown previously that ophthalmologists are more
.(CP. d likely to refer a patient for cataract surgery if the patient is
nNt1C employed and less likely to refer a nursing home resident.7
&--ej
|n In the Visual Impairment Project, we did not find that any
bm% $86 particular subgroup of the population was at greater risk of
alq%H}FF having unoperated cataract. Universal access to health care
Np+&t} in Australia may explain the fact that people without
"Wo,'8{v Medicare are more likely to delay cataract operations in the
$~;D9 USA,8 but not having private health insurance is not associated
/
X'(3'a with unoperated cataract in Australia.
y|
wlq3o In summary, cataract is a significant public health problem
G
L{57 in that one in four people in their 80s will have had cataract
re?s.djT surgery. The importance of age-related cataract surgery will
T"7~AbgNU increase further with the ageing of the population: the
ma'FRt number of people over age 60 years is expected to double in
Y5ZZ3Ati the next 20 years. Cataract surgery services are well
*^%Q0mU[ accessed by the Victorian population and the visual outcomes
-!W<DJ* of cataract surgery have been shown to be very good.
Z_1U
9+, These data can be used to plan for age-related cataract
A+J*e surgical services in Australia in the future as the need for
?`zXLY9q7 cataract extractions increases.
k@ZLg9 ACKNOWLEDGEMENTS
U8qtwA9t The Visual Impairment Project was funded in part by grants
w}Uhd, from the Victorian Health Promotion Foundation, the
6`vC1PK^ National Health and Medical Research Council, the Ansell
./Q, Ophthalmology Foundation, the Dorothy Edols Estate and
+)o}c"P! the Jack Brockhoff Foundation. Dr McCarty is the recipient
FFdBtB of a Wagstaff Fellowship in Ophthalmology from the Royal
>h0-; Victorian Eye and Ear Hospital.
J+d1&Tw& REFERENCES
r{l(O,|e 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
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