ABSTRACT
>jhcSvM6 Purpose: To quantify the prevalence of cataract, the outcomes
M*gvYo of cataract surgery and the factors related to
0j!3\=P$ unoperated cataract in Australia.
sPvs}}Z]P Methods: Participants were recruited from the Visual
=f!A o:Uc Impairment Project: a cluster, stratified sample of more than
cLf90|YFp 5000 Victorians aged 40 years and over. At examination
zl:by? sites interviews, clinical examinations and lens photography
p7Wt(A were performed. Cataract was defined in participants who
n!/0yR2S had: had previous cataract surgery, cortical cataract greater
<|_>r`@%l than 4/16, nuclear greater than Wilmer standard 2, or
`KA==;0 posterior subcapsular greater than 1 mm2.
-@(LN%7!C Results: The participant group comprised 3271 Melbourne
Wn@oG@}~ residents, 403 Melbourne nursing home residents and 1473
yM@sGz6c! rural residents.The weighted rate of any cataract in Victoria
uE')<fVX( was 21.5%. The overall weighted rate of prior cataract
)v_Wn[Y.H surgery was 3.79%. Two hundred and forty-nine eyes had
g@>l
lve{ had prior cataract surgery. Of these 249 procedures, 49
_dd! nU\A| (20%) were aphakic, 6 (2.4%) had anterior chamber
IsI5c intraocular lenses and 194 (78%) had posterior chamber
3=uhy|f! / intraocular lenses.Two hundred and eleven of these operated
EO)JMV?6 eyes (85%) had best-corrected visual acuity of 6/12 or
q1:dcxR[
better, the legal requirement for a driver’s license.Twentyseven
5`p9Xo>)yW (11%) had visual acuity of less than 6/18 (moderate
qG;tD>jy vision impairment). Complications of cataract surgery
T4.wz
58
caused reduced vision in four of the 27 eyes (15%), or 1.9%
gW~T{+f of operated eyes. Three of these four eyes had undergone
Ak@!F6~ intracapsular cataract extraction and the fourth eye had an
)]C]KB opaque posterior capsule. No one had bilateral vision
?m*e$!M0 impairment as a result of cataract surgery. Surprisingly, no
p\=T
#lb particular demographic factors (such as age, gender, rural
h<%$?h+} residence, occupation, employment status, health insurance
%RV81H9B status, ethnicity) were related to the presence of unoperated
ASbIc"S6 cataract.
%J-0%-/_S: Conclusions: Although the overall prevalence of cataract is
>M2~p&Si quite high, no particular subgroup is systematically underserviced
A3/[9}(U in terms of cataract surgery. Overall, the results of
\"ahs7ABT cataract surgery are very good, with the majority of eyes
7e+C5W*9b achieving driving vision following cataract extraction.
ZXb|3|D Key words: cataract extraction, health planning, health
=8 @DYz' services accessibility, prevalence
nu\
AEFT INTRODUCTION
y-+W Cataract is the leading cause of blindness worldwide and, in
iG5
4 +] Australia, cataract extractions account for the majority of all
5oG~Fc ophthalmic procedures.1 Over the period 1985–94, the rate
B%\&Q@X of cataract surgery in Australia was twice as high as would be
;iiCay37F expected from the growth in the elderly population.1
p48enH8CO Although there have been a number of studies reporting
ExtC\(X; the prevalence of cataract in various populations,2–6 there is
1=J& ^O{W little information about determinants of cataract surgery in
\|S%zX the population. A previous survey of Australian ophthalmologists
JY CMW!~ showed that patient concern and lifestyle, rather
gPCf+>X{ than visual acuity itself, are the primary factors for referral
1@OpvO5 for cataract surgery.7 This supports prior research which has
2|bt"y-5r shown that visual acuity is not a strong predictor of need for
=OFhM7 cataract surgery.8,9 Elsewhere, socioeconomic status has
qvc<_k^ been shown to be related to cataract surgery rates.10
:-jbIpj' To appropriately plan health care services, information is
&7\}Sqp needed about the prevalence of age-related cataract in the
E$
\l57 community as well as the factors associated with cataract
#@DJf surgery. The purpose of this study is to quantify the prevalence
!nl-}P, of any cataract in Australia, to describe the factors
~NIhS! related to unoperated cataract in the community and to
+TqrvI. describe the visual outcomes of cataract surgery.
TXi| METHODS
s\mA3t Study population
t4UK~ {gh Details about the study methodology for the Visual
} +Sp7F1q Impairment Project have been published previously.11
Ac U@H0 Briefly, cluster sampling within three strata was employed to
)dfhy recruit subjects aged 40 years and over to participate.
P0m9($JBD Within the Melbourne Statistical Division, nine pairs of
2z
!05]B% census collector districts were randomly selected. Fourteen
z` 6$p1U nursing homes within a 5 km radius of these nine test sites
~v(c9I) were randomly chosen to recruit nursing home residents.
E\D,=|Mul Clinical and Experimental Ophthalmology (2000) 28, 77–82
}i^M<A O Original Article
=aB+|E Operated and unoperated cataract in Australia
m^XO77" Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
Zocuc"j Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
J\+fkN<. n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
I<RARB-j Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au v CsE|e
MP 78 McCarty et al.
;!f~
Finally, four pairs of census collector districts in four rural
=SmU;t>t/ Victorian communities were randomly selected to recruit rural
KgM|:' residents. A household census was conducted to identify
)T9Cv8 eligible residents aged 40 years and over who had been a
SM)"vr_ resident at that address for at least 6 months. At the time of
F-ZTy"z the household census, basic information about age, sex,
^@/wXj: country of birth, language spoken at home, education, use of
3M?O(oO corrective spectacles and use of eye care services was collected.
<m\Y$Wv Eligible residents were then invited to attend a local
1v:Ql\^cT examination site for a more detailed interview and examination.
rNhS\1- The study protocol was approved by the Royal Victorian
HgW!Q(* Eye and Ear Hospital Human Research Ethics Committee.
8Kl&_-l{b Assessment of cataract
@BLB.= A standardized ophthalmic examination was performed after
G?v<-=I pupil dilatation with one drop of 10% phenylephrine
-cUbIbW hydrochloride. Lens opacities were graded clinically at the
>|Ro
LV time of the examination and subsequently from photos using
&V
7J5~_ the Wilmer cataract photo-grading system.12 Cortical and
;g8v7>p posterior subcapsular (PSC) opacities were assessed on
Hc8^w6S1@ retroillumination and measured as the proportion (in 1/16)
*VXx\& of pupil circumference occupied by opacity. For this analysis,
G)YmaHeI;[ cortical cataract was defined as 4/16 or greater opacity,
LkHH7Pd@ PSC cataract was defined as opacity equal to or greater than
(D[~Z!
1 mm2 and nuclear cataract was defined as opacity equal to
}U=}5`_]D or greater than Wilmer standard 2,12 independent of visual
{9;-5@b acuity. Examples of the minimum opacities defined as cortical,
).GM0-y nuclear and PSC cataract are presented in Figure 1.
?IQDk|<% Bilateral congenital cataracts or cataracts secondary to
dY.X/f intraocular inflammation or trauma were excluded from the
0VQBm^$( analysis. Two cases of bilateral secondary cataract and eight
Zc38ht\r; cases of bilateral congenital cataract were excluded from the
eQyc
< analyses.
zQO 1%
g A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
\
H>Psv{ Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
:I/9j=@1 height set to an incident angle of 30° was used for examinations.
78:x{1nUM[ Ektachrome® 200 ASA colour slide film (Eastman
P//nYPyzg Kodak Company, Rochester, NY, USA) was used to photograph
I+W,%)vb the nuclear opacities. The cortical opacities were
s^6,"C photographed with an Oxford® retroillumination camera
<]z4;~/&
(Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
4gEw}
WiP film (Eastman Kodak). Photographs were graded separately
_d7;Z% by two research assistants and discrepancies were adjudicated
h
8M_Uk by an independent reviewer. Any discrepancies
p;7wH\c between the clinical grades and the photograph grades were
F5H*z\/={ resolved. Except in cases where photographs were missing,
R$IsP,Uw the photograph grades were used in the analyses. Photograph
dtV*CX.D.7 grades were available for 4301 (84%) for cortical
CD#U`jf cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
DfGq m-c for PSC cataract. Cataract status was classified according to
=B+dhZ+#S$ the severity of the opacity in the worse eye.
w(S&X"~ Assessment of risk factors
+3AX1o%p,# A standardized questionnaire was used to obtain information
.#sX|c=W about education, employment and ethnic background.11
u f<%!=e Specific information was elicited on the occurrence, duration
F#Pn] and treatment of a number of medical conditions,
}9B},
including ocular trauma, arthritis, diabetes, gout, hypertension
fTX|vy<EMI and mental illness. Information about the use, dose and
YsiH=x duration of tobacco, alcohol, analgesics and steriods were
#/9Y}2G|] collected, and a food frequency questionnaire was used to
bx6=LK determine current consumption of dietary sources of antioxidants
MVQ6I/EA4 and use of vitamin supplements.
2RqV\Jik Data management and statistical analysis
RxPD44jVA Data were collected either by direct computer entry with a
41.xi9V2 questionnaire programmed in Paradox© (Carel Corporation,
i(e= Ottawa, Canada) with internal consistency checks, or
6_rgRo& on self-coding forms. Open-ended responses were coded at
#U3q
+d+^ a later time. Data that were entered on the self-coded forms
kDR5kD
iS were entered into a computer with double data entry and
BlT)hG(M> reconciliation of any inconsistencies. Data range and consistency
zw5Ol%JF checks were performed on the entire data set.
-m=!SQ >9 SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
?mVSc/ employed for statistical analyses.
]H`pM9rC Ninety-five per cent confidence limits around the agespecific
!w!k0z] rates were calculated according to Cochran13 to
|XQ\c.A account for the effect of the cluster sampling. Ninety-five
g38
MF per cent confidence limits around age-standardized rates
siV]NI':| were calculated according to Breslow and Day.14 The strataspecific
t!FC)iY data were weighted according to the 1996
ofYZ!-V Australian Bureau of Statistics census data15 to reflect the
K1;b4Sl?A cataract prevalence in the entire Victorian population.
ycIcM~<4 Univariate analyses with Student’s t-tests and chi-squared
r M}o) tests were first employed to evaluate risk factors for unoperated
w&hCtc cataract. Any factors with P < 0.10 were then fitted
Nd;pkssd into a backwards stepwise logistic regression model. For the
7coVl$_Zl Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
yS?5&oMl final multivariate models, P < 0.05 was considered statistically
GJ?J6@| significant. Design effect was assessed through the use
Ak}`zIo of cluster-specific models and multivariate models. The
c4Q%MRR design effect was assumed to be additive and an adjustment
.F _u/"** made in the variance by adding the variance associated with
v[DxWs8q the design effect prior to constructing the 95% confidence
%bG\ limits.
@a
B7dtM RESULTS
!Ap*PL Study population
urL@SeV+$ A total of 3271 (83%) of the Melbourne residents, 403
%?/vC
6 (90%) Melbourne nursing home residents, and 1473 (92%)
[*H h6 rural residents participated. In general, non-participants did
h>z5m not differ from participants.16 The study population was
)2jH&}K representative of the Victorian population and Australia as
zf\$T,t) a whole.
Io/;+R. The Melbourne residents ranged in age from 40 to
3r?T|>| 98 years (mean = 59) and 1511 (46%) were male. The
y"_rDj` Melbourne nursing home residents ranged in age from 46 to
P|;v> 101 years (mean = 82) and 85 (21%) were men. The rural
:o:/RRp[ residents ranged in age from 40 to 103 years (mean = 60)
#~r+Z[(,p and 701 (47.5%) were men.
|b!Bb<5 Prevalence of cataract and prior cataract surgery
L5wFbc"u As would be expected, the rate of any cataract increases
Ga
<=Di): dramatically with age (Table 1). The weighted rate of any
Q[T)jo,j% cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
' 1dhdm8 Although the rates varied somewhat between the three
-(#`JT8 strata, they were not significantly different as the 95% confidence
+Q:)zE limits overlapped. The per cent of cataractous eyes
b:
I0Zv6 with best-corrected visual acuity of less than 6/12 was 12.5%
{JfL7% (65/520) for cortical cataract, 18% for nuclear cataract
GIS,EwA
(97/534) and 14.4% (27/187) for PSC cataract. Cataract
*M$$%G(4 surgery also rose dramatically with age. The overall
Ud#xgs' weighted rate of prior cataract surgery in Victoria was
=<P$mFP2* 3.79% (95% CL 2.97, 4.60) (Table 2).
^>y|{;` Risk factors for unoperated cataract
@~i :8 Cases of cataract that had not been removed were classified
H[?l)nZ} as unoperated cataract. Risk factor analyses for unoperated
GCxmqoQ cataract were not performed with the nursing home residents
:4Y5 as information about risk factor exposure was not
>ATccv available for this cohort. The following factors were assessed
0"mr*hyj in relation to unoperated cataract: age, sex, residence
TO/SiOd (urban/rural), language spoken at home (a measure of ethnic
Ai`0Ud,M@ integration), country of birth, parents’ country of birth (a
z
E\~Oa; measure of ethnicity), years since migration, education, use
ypTH=]y of ophthalmic services, use of optometric services, private
@M(+YCi:e@ health insurance status, duration of distance glasses use,
w!Ii glaucoma, age-related maculopathy and employment status.
)jw!,"_4 In this cross sectional study it was not possible to assess the
?+byRoY>&g level of visual acuity that would predict a patient’s having
6 _#CvQ cataract surgery, as visual acuity data prior to cataract
W: 3fLXk+ surgery were not available.
@CA{uP; The significant risk factors for unoperated cataract in univariate
y# IUDnRJ analyses were related to: whether a participant had
1@q"rPE^ ever seen an optometrist, seen an ophthalmologist or been
}Gd^r diagnosed with glaucoma; and participants’ employment
uAV-wc status (currently employed) and age. These significant
S\@U3|Q5 factors were placed in a backwards stepwise logistic regression
$A)[s$ model. The factors that remained significantly related
,d8*7my to unoperated cataract were whether participants had ever
Htce<H-P seen an ophthalmologist, seen an optometrist and been
is{H >#+" diagnosed with glaucoma. None of the demographic factors
cXt]55" were associated with unoperated cataract in the multivariate
YS>VQl model.
"X-"uIc The per cent of participants with unoperated cataract
5&}p'6*K who said that they were dissatisfied or very dissatisfied with
X7)B)r}AG Operated and unoperated cataract in Australia 79
T{*!.+E Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
mzn#4;m$ Age group Sex Urban Rural Nursing home Weighted total
#mRT>]di`D (years) (%) (%) (%)
H|<Zm:.%$ 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
>8gb/?z Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
F?4&qbdD 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
v3r<kNW_ Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
nOU.=N
v` 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
H) q_9<; Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
4R9y~~+ 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
t0)XdIl8 Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
R(#ZaFuo[ 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
#9q
]jjH E Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
uVzvUz{b 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
U;FJSy Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
jJe?pT]o Age-standardized
Di&XDW/ (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)
:E2 ww` aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
$u::(s}
x< their current vision was 30% (290/683), compared with 27%
dEPLkv (26/95) of participants with prior cataract surgery (chisquared,
6Vu)
1 d.f. = 0.25, P = 0.62).
B[;aNyd< Outcomes of cataract surgery
>]ZW.?1h Two hundred and forty-nine eyes had undergone prior
1F{,Zr cataract surgery. Of these 249 operated eyes, 49 (20%) were
__,F_9M left aphakic, 6 (2.4%) had anterior chamber intraocular
Eb9n6Fg lenses and 194 (78%) had posterior chamber intraocular
Tvd: P^C lenses. The rate of capsulotomy in the eyes with intact
(E7C
9U* posterior capsules was 36% (73/202). Fifteen per cent of
SX[ eyes (17/114) with a clear posterior capsule had bestcorrected
@
[%K D visual acuity of less than 6/12 compared with 43%
.:B;%* of eyes (6/14) with opaque capsules, and 15% of eyes
5a2+6N (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
!u|s8tN.U P = 0.027).
:dwP The percentage of eyes with best-corrected visual acuity
)Qh*@=$- of 6/12 or better was 96% (302/314) for eyes without
$dF$-y<[0 cataract, 88% (1417/1609) for eyes with prevalent cataract
P5&8^YV`N and 85% (211/249) for eyes with operated cataract (chisquared,
!twYjOryH[ 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
JHg
y&/ operated eyes (11%) had visual acuities of less than 6/18
lec3rv0) (moderate vision impairment) (Fig. 2). A cause of this
a.fdCI]% moderate visual impairment (but not the only cause) in four
k;jXVa (15%) eyes was secondary to cataract surgery. Three of these
^CP>|JWD^ four eyes had undergone intracapsular cataract extraction
Oe lf^&m and the fourth eye had an opaque posterior capsule. No one
nRs:^Q~o had bilateral vision impairment as a result of their cataract
Hh*
KcIRX surgery.
- #-Bo DISCUSSION
r\FduyOXv To our knowledge, this is the first paper to systematically
xMFEeSzl>S assess the prevalence of current cataract, previous cataract
u=7#_ZC9L surgery, predictors of unoperated cataract and the outcomes
$>rKm
of cataract surgery in a population-based sample. The Visual
4mnVXKt%. Impairment Project is unique in that the sampling frame and
9s?gI4XN high response rate have ensured that the study population is
Bv#?
.0Ez; representative of Australians aged 40 years and over. Therefore,
'u6n,yRm these data can be used to plan age-related cataract
z-h?Q4; services throughout Australia.
L9d|7.b We found the rate of any cataract in those over the age
f9vitFkb+ of 40 years to be 22%. Although relatively high, this rate is
'l_F@ZO{( significantly less than was reported in a number of previous
3ej[ studies,2,4,6 with the exception of the Casteldaccia Eye
se*k56, Study.5 However, it is difficult to compare rates of cataract
<7`U1DR= between studies because of different methodologies and
svtqX-Vj" cataract definitions employed in the various studies, as well
~Gl5O`w( as the different age structures of the study populations.
:"cKxd Other studies have used less conservative definitions of
}yw>d\] f cataract, thus leading to higher rates of cataract as defined.
k}!'@ In most large epidemiologic studies of cataract, visual acuity
?RS4oJz,5g has not been included in the definition of cataract.
~cV";cD5 Therefore, the prevalence of cataract may not reflect the
zF(abQ0 actual need for cataract surgery in the community.
ll*Ez"
80 McCarty et al.
P_)=sj!>- Table 2. Prevalence of previous cataract by age, gender and cohort
syCT)}T6z Age group Gender Urban Rural Nursing home Weighted total
1fC)&4W (years) (%) (%) (%)
4/OmgBo' 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
}zqo<o Female 0.00 0.00 0.00 0.00 (
Y^y:N$3$\ 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
E6M*o+Y Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
Q\N >W+d 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
[z!pm-Ir Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
kSEgq<i! 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
P)LOAe1' Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
.[Qi4jm>` 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
}pGjc_:'] Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
| GN/{KH] 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
=woP~+ Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
|~&cTDd Age-standardized
Fk9]u^j (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)
9e.$x%7
j Figure 2. Visual acuity in eyes that had undergone cataract
\U##b~Z,g surgery, n = 249. h, Presenting; j, best-corrected.
vU(fd!V ? Operated and unoperated cataract in Australia 81
Z#D*HAd` The weighted prevalence of prior cataract surgery in the
fxmY,{{ Visual Impairment Project (3.6%) was similar to the crude
3Tp8t6*nL rate in the Beaver Dam Eye Study4 (3.1%), but less than the
Y*{5'q+2 crude rate in the Blue Mountains Eye Study6 (6.0%).
btC6R>0 However, the age-standardized rate in the Blue Mountains
u:tcL-;U
Eye Study (standardized to the age distribution of the urban
mn*}U R Visual Impairment Project cohort) was found to be less than
#{#k;va the Visual Impairment Project (standardized rate = 1.36%,
MZxU)QW1 95% CL 1.25, 1.47). The incidence of cataract surgery in
RCoDdtMo Australia has exceeded population growth.1 This is due,
Db;>MWt+e perhaps, to advances in surgical techniques and lens
U#Iwe= implants that have changed the risk–benefit ratio.
5.DmMG[T^= The Global Initiative for the Elimination of Avoidable
[:qJ1^UU Blindness, sponsored by the World Health Organization,
(ti!Y"e2 states that cataract surgical services should be provided that
9U4[o<G]= ‘have a high success rate in terms of visual outcome and
`Q#)N0 improved quality of life’,17 although the ‘high success rate’ is
J<4_<.o(a not defined. Population- and clinic-based studies conducted
W~a|AU8]C in the United States have demonstrated marked improvement
:RwURv+kT in visual acuity following cataract surgery.18–20 We
f`_{SU"3 found that 85% of eyes that had undergone cataract extraction
_wX(OB had visual acuity of 6/12 or better. Previously, we have
{u9n?Z% shown that participants with prevalent cataract in this
BE],PCpPr cohort are more likely to express dissatisfaction with their
R0F [ current vision than participants without cataract or participants
uXvE>VpJG with prior cataract surgery.21 In a national study in the
7i'clB9! United States, researchers found that the change in patients’
^:mKTiA- ratings of their vision difficulties and satisfaction with their
3orL;(.G vision after cataract surgery were more highly related to
i)$+#N their change in visual functioning score than to their change
a=x&sz\x in visual acuity.19 Furthermore, improvement in visual function
1?3+> has been shown to be associated with improvement in
%_CL/H
overall quality of life.22
M?Q
\
Hw A recent review found that the incidence of visually
g& f)WQ( significant posterior capsule opacification following
g_k95k3V' cataract surgery to be greater than 25%.23 We found 36%
a`]ZyG*P capsulotomy in our population and that this was associated
6}0_o[23 with visual acuity similar to that of eyes with a clear
+2}Ar<el
P capsule, but significantly better than that of eyes with an
|9Yx`_DF opaque capsule.
9C{Xpu A number of studies have shown that the demand and
SG&H^V8 timing of cataract surgery vary according to visual acuity,
k6GQH@y! degree of handicap and socioeconomic factors.8–10,24,25 We
Ux{QYjFE have also shown previously that ophthalmologists are more
RBg2iG$8| likely to refer a patient for cataract surgery if the patient is
d{) =E8wE employed and less likely to refer a nursing home resident.7
'J!Gip , In the Visual Impairment Project, we did not find that any
gp~-n7'~O particular subgroup of the population was at greater risk of
20}]b*C} having unoperated cataract. Universal access to health care
B<h4ZK% in Australia may explain the fact that people without
+ut%C.1
Medicare are more likely to delay cataract operations in the
Z0D&ayzkh^ USA,8 but not having private health insurance is not associated
.i*ja* with unoperated cataract in Australia.
-em3 #V In summary, cataract is a significant public health problem
-;RAW1]}Y$ in that one in four people in their 80s will have had cataract
0"+QWh surgery. The importance of age-related cataract surgery will
cIkA ~F increase further with the ageing of the population: the
l^o>7 cM number of people over age 60 years is expected to double in
a8%T*mk( the next 20 years. Cataract surgery services are well
xlgT1b:6 accessed by the Victorian population and the visual outcomes
C:bA:O of cataract surgery have been shown to be very good.
h"}F3E These data can be used to plan for age-related cataract
-XkjO$=!= surgical services in Australia in the future as the need for
T2mZkK?rA cataract extractions increases.
L;b-=mF ACKNOWLEDGEMENTS
?V_v=X%w The Visual Impairment Project was funded in part by grants
YhAO from the Victorian Health Promotion Foundation, the
;;U&mhz` National Health and Medical Research Council, the Ansell
Ls.g\Gl3 Ophthalmology Foundation, the Dorothy Edols Estate and
zx"0^r} the Jack Brockhoff Foundation. Dr McCarty is the recipient
Yx ;j of a Wagstaff Fellowship in Ophthalmology from the Royal
7Bf4ojKt Victorian Eye and Ear Hospital.
Z vyF"4QN REFERENCES
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