ABSTRACT
hRN
nj Purpose: To quantify the prevalence of cataract, the outcomes
;LC?3. of cataract surgery and the factors related to
p4@0[z' unoperated cataract in Australia.
[7\x(W-:@> Methods: Participants were recruited from the Visual
S"/-)_{ Impairment Project: a cluster, stratified sample of more than
R:`)*=rL% 5000 Victorians aged 40 years and over. At examination
\b}%A&Ij sites interviews, clinical examinations and lens photography
P}"T3u\N were performed. Cataract was defined in participants who
X4JSI%E had: had previous cataract surgery, cortical cataract greater
k+zskfo than 4/16, nuclear greater than Wilmer standard 2, or
A`* l+M^z posterior subcapsular greater than 1 mm2.
G8.nKoHv7x Results: The participant group comprised 3271 Melbourne
+q%b'!&Q residents, 403 Melbourne nursing home residents and 1473
B dP+>Ij rural residents.The weighted rate of any cataract in Victoria
s`|KT&r was 21.5%. The overall weighted rate of prior cataract
ovZ!} surgery was 3.79%. Two hundred and forty-nine eyes had
!xU[BCbfYV had prior cataract surgery. Of these 249 procedures, 49
'A9Z (( (20%) were aphakic, 6 (2.4%) had anterior chamber
M[C)b\ intraocular lenses and 194 (78%) had posterior chamber
"-P z2QJY intraocular lenses.Two hundred and eleven of these operated
;u=%Vn"2a eyes (85%) had best-corrected visual acuity of 6/12 or
@SI,V8i better, the legal requirement for a driver’s license.Twentyseven
/I:&P Pff (11%) had visual acuity of less than 6/18 (moderate
6m@B.+1 vision impairment). Complications of cataract surgery
g""Ep caused reduced vision in four of the 27 eyes (15%), or 1.9%
j@{ B 8 of operated eyes. Three of these four eyes had undergone
OlgM7Vrl intracapsular cataract extraction and the fourth eye had an
:sttGXQX opaque posterior capsule. No one had bilateral vision
yY]E~ impairment as a result of cataract surgery. Surprisingly, no
G=LK
irj( particular demographic factors (such as age, gender, rural
Z@bSkO<Y residence, occupation, employment status, health insurance
y8Rq2jI;(e status, ethnicity) were related to the presence of unoperated
Ro;I%j cataract.
\Yn0|j> Conclusions: Although the overall prevalence of cataract is
>hzSd@J& quite high, no particular subgroup is systematically underserviced
1vS-m x in terms of cataract surgery. Overall, the results of
n
TD4^' cataract surgery are very good, with the majority of eyes
T=RabKVYP achieving driving vision following cataract extraction.
zFQm3 !. Key words: cataract extraction, health planning, health
u\"/EaQ{ services accessibility, prevalence
#$]8WSl INTRODUCTION
T^{=c
x9x9 Cataract is the leading cause of blindness worldwide and, in
[KCR@__ Australia, cataract extractions account for the majority of all
VGc.yM)&
j ophthalmic procedures.1 Over the period 1985–94, the rate
jeB"j of cataract surgery in Australia was twice as high as would be
Yh Ow0 x expected from the growth in the elderly population.1
G(ZEP.h`u Although there have been a number of studies reporting
J#q^CWN3R the prevalence of cataract in various populations,2–6 there is
,6o tm little information about determinants of cataract surgery in
<
+kdL the population. A previous survey of Australian ophthalmologists
i29a1nD4Hm showed that patient concern and lifestyle, rather
}8s&~fH than visual acuity itself, are the primary factors for referral
AX{7].)F for cataract surgery.7 This supports prior research which has
Z3=N= xY] shown that visual acuity is not a strong predictor of need for
9}L2$^#,NA cataract surgery.8,9 Elsewhere, socioeconomic status has
d+6q%U been shown to be related to cataract surgery rates.10
j(}pUV B To appropriately plan health care services, information is
G]{^.5 needed about the prevalence of age-related cataract in the
l;&kX6 w community as well as the factors associated with cataract
,el[A`b surgery. The purpose of this study is to quantify the prevalence
)]4=anJu@| of any cataract in Australia, to describe the factors
FMhuCl
2 related to unoperated cataract in the community and to
N2Ysi$ describe the visual outcomes of cataract surgery.
&FJr?hY% METHODS
y~wr4Q= Study population
bI_MF/r'' Details about the study methodology for the Visual
Oamz>Hplu Impairment Project have been published previously.11
6j+X@|2^ Briefly, cluster sampling within three strata was employed to
%Pj} recruit subjects aged 40 years and over to participate.
H
SGz- Within the Melbourne Statistical Division, nine pairs of
q_mxZM
-> census collector districts were randomly selected. Fourteen
U0srwt97S nursing homes within a 5 km radius of these nine test sites
M%W#0 were randomly chosen to recruit nursing home residents.
VZ y$0* Clinical and Experimental Ophthalmology (2000) 28, 77–82
K5\l
(BB Original Article
zr_L
V_e Operated and unoperated cataract in Australia
3K/'K[~ Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
yF%e)6 Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
pjFj{ n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
Z glU{sU Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au g jzWW0C 78 McCarty et al.
7~'%ThUb$- Finally, four pairs of census collector districts in four rural
Sm?|,C3V Victorian communities were randomly selected to recruit rural
rc~)%M<[2 residents. A household census was conducted to identify
[z+YXs!N eligible residents aged 40 years and over who had been a
; C(5lD&\5 resident at that address for at least 6 months. At the time of
%L7DC`
the household census, basic information about age, sex,
,:MUf]Ky country of birth, language spoken at home, education, use of
>i.$s corrective spectacles and use of eye care services was collected.
{4f%UnSz( Eligible residents were then invited to attend a local
jsr) examination site for a more detailed interview and examination.
NLYf The study protocol was approved by the Royal Victorian
;X0uA? Eye and Ear Hospital Human Research Ethics Committee.
<S6?L[_ Assessment of cataract
E?|NYu#I6 A standardized ophthalmic examination was performed after
u|u)8;'9( pupil dilatation with one drop of 10% phenylephrine
>r,z^]- hydrochloride. Lens opacities were graded clinically at the
AeN:wOm time of the examination and subsequently from photos using
>uQjygjj the Wilmer cataract photo-grading system.12 Cortical and
DAORfFG74 posterior subcapsular (PSC) opacities were assessed on
ba
,n/yH retroillumination and measured as the proportion (in 1/16)
H!6&'=c {k of pupil circumference occupied by opacity. For this analysis,
CtD<%v3` cortical cataract was defined as 4/16 or greater opacity,
lb=fS% PSC cataract was defined as opacity equal to or greater than
]iFW>N*a 1 mm2 and nuclear cataract was defined as opacity equal to
HJpx,NU' or greater than Wilmer standard 2,12 independent of visual
FB>P39u acuity. Examples of the minimum opacities defined as cortical,
2_?VR~mA# nuclear and PSC cataract are presented in Figure 1.
jO*H8XO Bilateral congenital cataracts or cataracts secondary to
F J?]|S.?, intraocular inflammation or trauma were excluded from the
<4 /q5*& analysis. Two cases of bilateral secondary cataract and eight
(R RRG;*n# cases of bilateral congenital cataract were excluded from the
Zc&pJP+M'U analyses.
np}0OX A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
%.\+j,G7 Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
1}ifJ~)5S height set to an incident angle of 30° was used for examinations.
HyYJ"54 Ektachrome® 200 ASA colour slide film (Eastman
19oyoi" Kodak Company, Rochester, NY, USA) was used to photograph
HoWK#Nz\ the nuclear opacities. The cortical opacities were
)2Y]A^ Y photographed with an Oxford® retroillumination camera
< mFU T (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
9~K+h/ film (Eastman Kodak). Photographs were graded separately
XJq]l6a: by two research assistants and discrepancies were adjudicated
]A l)> by an independent reviewer. Any discrepancies
eU]I !pI< between the clinical grades and the photograph grades were
j4=\MK resolved. Except in cases where photographs were missing,
rO/Sj<0^ the photograph grades were used in the analyses. Photograph
cN\_1 grades were available for 4301 (84%) for cortical
Hbu
:HFJ! cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
Un5 AStG for PSC cataract. Cataract status was classified according to
yaHkWkl
= the severity of the opacity in the worse eye.
-`t9@1P>
= Assessment of risk factors
3z"%ht~; A standardized questionnaire was used to obtain information
p}X *HJq$ about education, employment and ethnic background.11
RyWfoLc Specific information was elicited on the occurrence, duration
`sd
H
q and treatment of a number of medical conditions,
vEt+^3= including ocular trauma, arthritis, diabetes, gout, hypertension
kmu7~&75 and mental illness. Information about the use, dose and
D>-Pv-f/ duration of tobacco, alcohol, analgesics and steriods were
GW.Y
=S collected, and a food frequency questionnaire was used to
!D/W6Ic@ determine current consumption of dietary sources of antioxidants
7Q&S []) and use of vitamin supplements.
Gxt6]+r Data management and statistical analysis
T
@n};,SQ Data were collected either by direct computer entry with a
`vf]C' questionnaire programmed in Paradox© (Carel Corporation,
UHIXy#+o5 Ottawa, Canada) with internal consistency checks, or
ydE}.0zN on self-coding forms. Open-ended responses were coded at
0rAuK7 a later time. Data that were entered on the self-coded forms
A 0;ng2& were entered into a computer with double data entry and
5<7sVd. reconciliation of any inconsistencies. Data range and consistency
@CC
6`D checks were performed on the entire data set.
@U =~c9 SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
4-C'2? employed for statistical analyses.
shVEAT'` Ninety-five per cent confidence limits around the agespecific
d"lk"R rates were calculated according to Cochran13 to
xb&,9Lxd| account for the effect of the cluster sampling. Ninety-five
[-R[rF per cent confidence limits around age-standardized rates
~/2OK!M were calculated according to Breslow and Day.14 The strataspecific
|jcIn[)= data were weighted according to the 1996
Lo=n)cV 1, Australian Bureau of Statistics census data15 to reflect the
iaRCV6cl cataract prevalence in the entire Victorian population.
l}D /1~d Univariate analyses with Student’s t-tests and chi-squared
jQ-2SA O tests were first employed to evaluate risk factors for unoperated
gy"<[N
.?c cataract. Any factors with P < 0.10 were then fitted
O! _d5r&, into a backwards stepwise logistic regression model. For the
CKC5S^Mx Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
9A9T'g)Du final multivariate models, P < 0.05 was considered statistically
4Wa*Pcj significant. Design effect was assessed through the use
? ^`fPH=
of cluster-specific models and multivariate models. The
*0<)PJ T design effect was assumed to be additive and an adjustment
EIPX q made in the variance by adding the variance associated with
f5/s+H! the design effect prior to constructing the 95% confidence
Q2*
~9QkU limits.
wGxH RESULTS
1had8K- Study population
6-+wfrN2 A total of 3271 (83%) of the Melbourne residents, 403
]<C]&03)) (90%) Melbourne nursing home residents, and 1473 (92%)
K\.tR rural residents participated. In general, non-participants did
jWdZ]0m not differ from participants.16 The study population was
js%n]$N representative of the Victorian population and Australia as
"akAGa!V+ a whole.
%.HLO.A The Melbourne residents ranged in age from 40 to
q4,/RZhzh 98 years (mean = 59) and 1511 (46%) were male. The
Ty7)j]b"zl Melbourne nursing home residents ranged in age from 46 to
s^Xs*T@~h 101 years (mean = 82) and 85 (21%) were men. The rural
4vCUVo r residents ranged in age from 40 to 103 years (mean = 60)
?TI]0) and 701 (47.5%) were men.
B![:fiR` Prevalence of cataract and prior cataract surgery
;<"V},
C As would be expected, the rate of any cataract increases
q+cD dramatically with age (Table 1). The weighted rate of any
=&(e* u_ cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
($W%&(:/ Although the rates varied somewhat between the three
#rNc+
strata, they were not significantly different as the 95% confidence
+wQ}ZP& limits overlapped. The per cent of cataractous eyes
k4E9=y? with best-corrected visual acuity of less than 6/12 was 12.5%
q- 0q: (65/520) for cortical cataract, 18% for nuclear cataract
B]6Lbp"oo (97/534) and 14.4% (27/187) for PSC cataract. Cataract
p(K^Zc surgery also rose dramatically with age. The overall
%s^1 de weighted rate of prior cataract surgery in Victoria was
oK$Krrs0& 3.79% (95% CL 2.97, 4.60) (Table 2).
5?([jAOf Risk factors for unoperated cataract
dDD5OnWmJ Cases of cataract that had not been removed were classified
A}&YK,$5ED as unoperated cataract. Risk factor analyses for unoperated
fNfa.0s cataract were not performed with the nursing home residents
6a_U[-a9; as information about risk factor exposure was not
E'5KJn;_7 available for this cohort. The following factors were assessed
nwC*w`4 in relation to unoperated cataract: age, sex, residence
.D\oKhV( (urban/rural), language spoken at home (a measure of ethnic
Fw
t integration), country of birth, parents’ country of birth (a
Q1rEUbvCE measure of ethnicity), years since migration, education, use
$R+gA{49% of ophthalmic services, use of optometric services, private
z(
}w| health insurance status, duration of distance glasses use,
5h0Hk<N glaucoma, age-related maculopathy and employment status.
kqxq'Aq)d In this cross sectional study it was not possible to assess the
}V`_(%Q-e level of visual acuity that would predict a patient’s having
|5X59!
JL cataract surgery, as visual acuity data prior to cataract
"*N#-=MJF surgery were not available.
dU2; The significant risk factors for unoperated cataract in univariate
5MKM;6cA&p analyses were related to: whether a participant had
z!18Jh ever seen an optometrist, seen an ophthalmologist or been
AXSip diagnosed with glaucoma; and participants’ employment
Un,'a8>V` status (currently employed) and age. These significant
^;.u}W factors were placed in a backwards stepwise logistic regression
D
.LR-Z model. The factors that remained significantly related
$!y^t$u$@ to unoperated cataract were whether participants had ever
4cM0f,nc+ seen an ophthalmologist, seen an optometrist and been
O8_!!Qd diagnosed with glaucoma. None of the demographic factors
:FtV~^Z were associated with unoperated cataract in the multivariate
\%.oi@A model.
M0 \gp@Fe The per cent of participants with unoperated cataract
Xw<
;)m who said that they were dissatisfied or very dissatisfied with
)b>misb/ Operated and unoperated cataract in Australia 79
0GeL">v,:= Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
rqdN%=C Age group Sex Urban Rural Nursing home Weighted total
!>80p~L (years) (%) (%) (%)
&GJVFr~z 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
d|7LCW+HW Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
?wCX:?g 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
~> lqEa Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
CI-za !T 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
?eX/vqk Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
As,e.V5! 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
|UMm>.\' Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
w5~j|c=_W 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
7Re\*[)T Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
CM++:Y vJ 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
ryh"/lu[B Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
" M?dU^U^ Age-standardized
4
l-UrnZ (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)
SlR//h aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
RJerx:] their current vision was 30% (290/683), compared with 27%
su1fsoL0 (26/95) of participants with prior cataract surgery (chisquared,
DwGM+)! 1 d.f. = 0.25, P = 0.62).
RO/(Ldh Outcomes of cataract surgery
w)@Wug Two hundred and forty-nine eyes had undergone prior
~S;-sxoO0l cataract surgery. Of these 249 operated eyes, 49 (20%) were
Pvi2j&W84 left aphakic, 6 (2.4%) had anterior chamber intraocular
,@?9H ~\ lenses and 194 (78%) had posterior chamber intraocular
Fb%?qaLmCv lenses. The rate of capsulotomy in the eyes with intact
v^t7)nx^ posterior capsules was 36% (73/202). Fifteen per cent of
5>
0\= eyes (17/114) with a clear posterior capsule had bestcorrected
@_-,
Q5 visual acuity of less than 6/12 compared with 43%
C5I7\
9F) of eyes (6/14) with opaque capsules, and 15% of eyes
C12V_)~2 (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
9cP{u$ P = 0.027).
w->Y92q] The percentage of eyes with best-corrected visual acuity
Y!_c/ !Tx of 6/12 or better was 96% (302/314) for eyes without
:" !Z9l\@
cataract, 88% (1417/1609) for eyes with prevalent cataract
2672oFD and 85% (211/249) for eyes with operated cataract (chisquared,
?yq=
c 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
0,DrVGa operated eyes (11%) had visual acuities of less than 6/18
Zf!Q4a
" (moderate vision impairment) (Fig. 2). A cause of this
_&V,yp!|
moderate visual impairment (but not the only cause) in four
g%S/)R,,ct (15%) eyes was secondary to cataract surgery. Three of these
nTr]NBR four eyes had undergone intracapsular cataract extraction
IA.7If&k and the fourth eye had an opaque posterior capsule. No one
q 9xA.* had bilateral vision impairment as a result of their cataract
V^[&4 surgery.
]9/A=p?J@ DISCUSSION
[y'blCb To our knowledge, this is the first paper to systematically
qX-5/;n assess the prevalence of current cataract, previous cataract
L$OZ]
surgery, predictors of unoperated cataract and the outcomes
aQx6;PC
of cataract surgery in a population-based sample. The Visual
k
$^/$N Impairment Project is unique in that the sampling frame and
hjg1By( high response rate have ensured that the study population is
Fh)xm* u( representative of Australians aged 40 years and over. Therefore,
#
2^H{7 these data can be used to plan age-related cataract
G2I%^.s services throughout Australia.
|Vz)!M We found the rate of any cataract in those over the age
7:vl -ZW of 40 years to be 22%. Although relatively high, this rate is
61kSCu significantly less than was reported in a number of previous
t.;._' studies,2,4,6 with the exception of the Casteldaccia Eye
2H9hN4N Study.5 However, it is difficult to compare rates of cataract
iU 6,B between studies because of different methodologies and
vf.MSk?~ar cataract definitions employed in the various studies, as well
A8mc+ Bf( as the different age structures of the study populations.
Iga+8k Other studies have used less conservative definitions of
q9ra cataract, thus leading to higher rates of cataract as defined.
jnJ*e-AW In most large epidemiologic studies of cataract, visual acuity
v4|TQ8!wR has not been included in the definition of cataract.
Ir>4- @ Therefore, the prevalence of cataract may not reflect the
Xv!Gg6v6 actual need for cataract surgery in the community.
u=qK_$d4 80 McCarty et al.
7M~ /
q. Table 2. Prevalence of previous cataract by age, gender and cohort
*Xk5H,: Age group Gender Urban Rural Nursing home Weighted total
|T"vF`Kr(> (years) (%) (%) (%)
&\6},JN 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
V^Z5i]zT Female 0.00 0.00 0.00 0.00 (
4bL *7bA 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
Rf`_q7fm
Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
$ dI
mA 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
[5IbR9_ Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
J'ce?_\?PY 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
}Em{?Hqy Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
&':C"_|&r 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
iupkb Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
)N- '~<N
90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
^ICSh8C Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
`!N}u Age-standardized
R3og]=uFzm (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)
7NT}
Zwf Figure 2. Visual acuity in eyes that had undergone cataract
(Ox&B+\v+v surgery, n = 249. h, Presenting; j, best-corrected.
7)<Ib
j<M Operated and unoperated cataract in Australia 81
K:<Viz The weighted prevalence of prior cataract surgery in the
0|-}>>qb\ Visual Impairment Project (3.6%) was similar to the crude
!4+Die X rate in the Beaver Dam Eye Study4 (3.1%), but less than the
tik*[1it crude rate in the Blue Mountains Eye Study6 (6.0%).
5
5.2UN However, the age-standardized rate in the Blue Mountains
]8 }2 Eye Study (standardized to the age distribution of the urban
+Eb-|dM Visual Impairment Project cohort) was found to be less than
T'7>4MT( the Visual Impairment Project (standardized rate = 1.36%,
U}X'RCM 95% CL 1.25, 1.47). The incidence of cataract surgery in
S[9b
I&C Australia has exceeded population growth.1 This is due,
w{T$3F`@9 perhaps, to advances in surgical techniques and lens
T7mT:z>: implants that have changed the risk–benefit ratio.
[
>GblL The Global Initiative for the Elimination of Avoidable
: 9(kU Blindness, sponsored by the World Health Organization,
JE:LA+ ( states that cataract surgical services should be provided that
xzY/$? ‘have a high success rate in terms of visual outcome and
Ygg+=@].@ improved quality of life’,17 although the ‘high success rate’ is
"wV not defined. Population- and clinic-based studies conducted
Y{e,I-"{ in the United States have demonstrated marked improvement
|b='DJz2 in visual acuity following cataract surgery.18–20 We
K'8?%&IQ found that 85% of eyes that had undergone cataract extraction
7ZAxhFC had visual acuity of 6/12 or better. Previously, we have
/o$6"~t shown that participants with prevalent cataract in this
R=Lkf cohort are more likely to express dissatisfaction with their
V+>RF current vision than participants without cataract or participants
[8tpU&J with prior cataract surgery.21 In a national study in the
`r=^{Y United States, researchers found that the change in patients’
A6_ER&9$>N ratings of their vision difficulties and satisfaction with their
gJwX vision after cataract surgery were more highly related to
ueW/i their change in visual functioning score than to their change
0#yH<h$ in visual acuity.19 Furthermore, improvement in visual function
:G9d,B7* has been shown to be associated with improvement in
!F6rcDK I overall quality of life.22
po]<sB A recent review found that the incidence of visually
9P
<1/W! significant posterior capsule opacification following
0.!vp?
cataract surgery to be greater than 25%.23 We found 36%
+('xzW capsulotomy in our population and that this was associated
Y~( 8<`^ with visual acuity similar to that of eyes with a clear
c2GTN " capsule, but significantly better than that of eyes with an
SJ8
~:"\P opaque capsule.
z:O:g?A A number of studies have shown that the demand and
[ot+EA timing of cataract surgery vary according to visual acuity,
bS|h~B]rd degree of handicap and socioeconomic factors.8–10,24,25 We
.Q</0*sp have also shown previously that ophthalmologists are more
?gK|R likely to refer a patient for cataract surgery if the patient is
~:C`e4 employed and less likely to refer a nursing home resident.7
Y?oeP^V'u In the Visual Impairment Project, we did not find that any
)h(=X&(d particular subgroup of the population was at greater risk of
qMO(j%N5 having unoperated cataract. Universal access to health care
^'sy hI\ in Australia may explain the fact that people without
Xe
^NVF Medicare are more likely to delay cataract operations in the
Kx;l a USA,8 but not having private health insurance is not associated
z^KBV^n with unoperated cataract in Australia.
!a%_A^t7 In summary, cataract is a significant public health problem
~WmA55 in that one in four people in their 80s will have had cataract
^m.%FIwR surgery. The importance of age-related cataract surgery will
ncR]@8
increase further with the ageing of the population: the
/5>A 2y number of people over age 60 years is expected to double in
1B{u4w7S4e the next 20 years. Cataract surgery services are well
y]k{u\2A accessed by the Victorian population and the visual outcomes
"GxQ9=Z of cataract surgery have been shown to be very good.
)h%tEY$AJ These data can be used to plan for age-related cataract
2tp95E
`(O surgical services in Australia in the future as the need for
_ ^0UK|[ cataract extractions increases.
P>]*pD ACKNOWLEDGEMENTS
k#5Qwxu` The Visual Impairment Project was funded in part by grants
9$R}GK from the Victorian Health Promotion Foundation, the
EBUCG"e National Health and Medical Research Council, the Ansell
Q"GZh.m Ophthalmology Foundation, the Dorothy Edols Estate and
cEPqcy
* the Jack Brockhoff Foundation. Dr McCarty is the recipient
j;&su=p" of a Wagstaff Fellowship in Ophthalmology from the Royal
>
a 8'MK Victorian Eye and Ear Hospital.
[_tBv" z REFERENCES
7}fT7tsN 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
5mI}IS|@ Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
>s;dooZ 2. Sperduto RD, Hiller R. The prevalence of nuclear, cortical,
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