ABSTRACT
N8Rm}) Purpose: To quantify the prevalence of cataract, the outcomes
Gr`MGQ, of cataract surgery and the factors related to
\f8P`oET~ unoperated cataract in Australia.
?|%\<h@; Methods: Participants were recruited from the Visual
KK&<Vw|O\ Impairment Project: a cluster, stratified sample of more than
,\\%EZ%a 5000 Victorians aged 40 years and over. At examination
[0mFy)6 sites interviews, clinical examinations and lens photography
< fojX\}3 were performed. Cataract was defined in participants who
pDLu +}@ had: had previous cataract surgery, cortical cataract greater
*/0vJz%<.M than 4/16, nuclear greater than Wilmer standard 2, or
mB{&7Rb0 posterior subcapsular greater than 1 mm2.
[dSDg2] Results: The participant group comprised 3271 Melbourne
CT$& zEIm residents, 403 Melbourne nursing home residents and 1473
]Ssw32yn rural residents.The weighted rate of any cataract in Victoria
t
1Ir4 was 21.5%. The overall weighted rate of prior cataract
0%
GqCg surgery was 3.79%. Two hundred and forty-nine eyes had
p=mCK@ had prior cataract surgery. Of these 249 procedures, 49
PV,kYM6 (20%) were aphakic, 6 (2.4%) had anterior chamber
Z@>=
& intraocular lenses and 194 (78%) had posterior chamber
O<eWq] intraocular lenses.Two hundred and eleven of these operated
4~m.#6MT
eyes (85%) had best-corrected visual acuity of 6/12 or
:_{{PY0PK better, the legal requirement for a driver’s license.Twentyseven
z*NC?\ (11%) had visual acuity of less than 6/18 (moderate
.NzW@| vision impairment). Complications of cataract surgery
avHD'zU}N caused reduced vision in four of the 27 eyes (15%), or 1.9%
Vid{6?7kh of operated eyes. Three of these four eyes had undergone
h X>VVeIZ intracapsular cataract extraction and the fourth eye had an
U- *8%>Qp opaque posterior capsule. No one had bilateral vision
)JY_eG&2Dx impairment as a result of cataract surgery. Surprisingly, no
Q}=W>|aE. particular demographic factors (such as age, gender, rural
:XPC0^4s residence, occupation, employment status, health insurance
6h0U status, ethnicity) were related to the presence of unoperated
He0N cataract.
[0tfY0 Conclusions: Although the overall prevalence of cataract is
OUIUgej quite high, no particular subgroup is systematically underserviced
{LB
}v;?l in terms of cataract surgery. Overall, the results of
"&~?Hzm cataract surgery are very good, with the majority of eyes
M0Kh>u achieving driving vision following cataract extraction.
@sgT[P*ut Key words: cataract extraction, health planning, health
fbzKO^Ub services accessibility, prevalence
R+kZLOE INTRODUCTION
:9!0Rm Cataract is the leading cause of blindness worldwide and, in
\:q e3Q Australia, cataract extractions account for the majority of all
)v!lP pe8 ophthalmic procedures.1 Over the period 1985–94, the rate
}n2-*{)x of cataract surgery in Australia was twice as high as would be
q563,s expected from the growth in the elderly population.1
)- 6s7 Although there have been a number of studies reporting
m`yn9(1Y[ the prevalence of cataract in various populations,2–6 there is
z:i X]df little information about determinants of cataract surgery in
CtC`
:
!Q the population. A previous survey of Australian ophthalmologists
?D~SHcBaN showed that patient concern and lifestyle, rather
49J+&G?)j than visual acuity itself, are the primary factors for referral
+U_-Lq ) for cataract surgery.7 This supports prior research which has
X!+Mgh6 shown that visual acuity is not a strong predictor of need for
=@Nv:1:r cataract surgery.8,9 Elsewhere, socioeconomic status has
Y="&|c=w#L been shown to be related to cataract surgery rates.10
]}l+ !NV< To appropriately plan health care services, information is
,m?UFRi needed about the prevalence of age-related cataract in the
#G!Adj+p5 community as well as the factors associated with cataract
I_6` Z 0 surgery. The purpose of this study is to quantify the prevalence
PRk%C0` of any cataract in Australia, to describe the factors
WtdkA Sj related to unoperated cataract in the community and to
@6!y(e8"J] describe the visual outcomes of cataract surgery.
2gD{Fgf@N METHODS
:56lzsWUE< Study population
(Y.$wMB Details about the study methodology for the Visual
P7x?!71?L Impairment Project have been published previously.11
CMG`'gT Briefly, cluster sampling within three strata was employed to
1uge>o& recruit subjects aged 40 years and over to participate.
dzv,)X Within the Melbourne Statistical Division, nine pairs of
\IZ4( Z census collector districts were randomly selected. Fourteen
SQ
KY;p nursing homes within a 5 km radius of these nine test sites
w%o4MFK=! were randomly chosen to recruit nursing home residents.
W &wDH Clinical and Experimental Ophthalmology (2000) 28, 77–82
+heS\I_Mp Original Article
mV(x&`Cx Operated and unoperated cataract in Australia
!zkEh9G Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
XsN#<"f;i Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
0l1]QD+Gc5 n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
8`~3MsE" Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au 4e#K.HU_ 78 McCarty et al.
W>|b98NPu Finally, four pairs of census collector districts in four rural
E|4XQ|B@ Victorian communities were randomly selected to recruit rural
^%X\ }>< residents. A household census was conducted to identify
?{z${ bD eligible residents aged 40 years and over who had been a
u[|S*(P resident at that address for at least 6 months. At the time of
}~CZqI
P the household census, basic information about age, sex,
Z%9^6kdY country of birth, language spoken at home, education, use of
JHZo:Ad -& corrective spectacles and use of eye care services was collected.
h-rj Eligible residents were then invited to attend a local
K ':pU1 examination site for a more detailed interview and examination.
}0nB'0|y The study protocol was approved by the Royal Victorian
#:zPpMAl Eye and Ear Hospital Human Research Ethics Committee.
>(ww6vk2 Assessment of cataract
nN\XVGP,t A standardized ophthalmic examination was performed after
.F3LA6se pupil dilatation with one drop of 10% phenylephrine
_w/N[E hydrochloride. Lens opacities were graded clinically at the
hJ*E"{xs time of the examination and subsequently from photos using
>,Bu^] C the Wilmer cataract photo-grading system.12 Cortical and
zwrZ^ posterior subcapsular (PSC) opacities were assessed on
0fK|}mmZA retroillumination and measured as the proportion (in 1/16)
GXK?7S0H of pupil circumference occupied by opacity. For this analysis,
+<WT$ddK=5 cortical cataract was defined as 4/16 or greater opacity,
~wg^>!E PSC cataract was defined as opacity equal to or greater than
sx^? Iw,N' 1 mm2 and nuclear cataract was defined as opacity equal to
Oj
EA;;qq or greater than Wilmer standard 2,12 independent of visual
E
d/O\v@ acuity. Examples of the minimum opacities defined as cortical,
K$5P_~;QL nuclear and PSC cataract are presented in Figure 1.
Ru aJ9O Bilateral congenital cataracts or cataracts secondary to
W1`ZS*12D intraocular inflammation or trauma were excluded from the
c qyh#uWe analysis. Two cases of bilateral secondary cataract and eight
T2; 9 cases of bilateral congenital cataract were excluded from the
B"zg85
e analyses.
CHw_?#h A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
#p`7gFl Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
9d}
nyJ height set to an incident angle of 30° was used for examinations.
'="){ Ektachrome® 200 ASA colour slide film (Eastman
.T-p]9*p Kodak Company, Rochester, NY, USA) was used to photograph
*)D*iU& the nuclear opacities. The cortical opacities were
!I/kz }N@ photographed with an Oxford® retroillumination camera
ClZyQ=UAD (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
Li^!OHro. film (Eastman Kodak). Photographs were graded separately
KptLeb:Om by two research assistants and discrepancies were adjudicated
v[3sg2. by an independent reviewer. Any discrepancies
?.ihWbW_ between the clinical grades and the photograph grades were
e'VXyf resolved. Except in cases where photographs were missing,
#7ZBbq3= the photograph grades were used in the analyses. Photograph
Z5-'|h$| grades were available for 4301 (84%) for cortical
xyz86r ^u cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
7Z3qaXPH for PSC cataract. Cataract status was classified according to
ttVSgKAsm the severity of the opacity in the worse eye.
>GUTno$J Assessment of risk factors
"iGc'?/+ A standardized questionnaire was used to obtain information
.&.CbE8K[ about education, employment and ethnic background.11
)D*xOajo+l Specific information was elicited on the occurrence, duration
yqI|BF` and treatment of a number of medical conditions,
CNYchE,} including ocular trauma, arthritis, diabetes, gout, hypertension
?0Zw
^a
and mental illness. Information about the use, dose and
N*>; ' duration of tobacco, alcohol, analgesics and steriods were
,-kZ5&r collected, and a food frequency questionnaire was used to
^O
m]B; determine current consumption of dietary sources of antioxidants
\_bX2Lg and use of vitamin supplements.
.R5
z>:A Data management and statistical analysis
S~Q";C[& Data were collected either by direct computer entry with a
-',Y;0b% questionnaire programmed in Paradox© (Carel Corporation,
W:J00rsv=` Ottawa, Canada) with internal consistency checks, or
#u@!O%MJ on self-coding forms. Open-ended responses were coded at
PQr
N";+ a later time. Data that were entered on the self-coded forms
_Tz!~z were entered into a computer with double data entry and
C:{'0m*jKs reconciliation of any inconsistencies. Data range and consistency
&KWh5S@w checks were performed on the entire data set.
W9~datIh> SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
H1M>60* employed for statistical analyses.
Rw`s O:eZ Ninety-five per cent confidence limits around the agespecific
Ipx:k+J rates were calculated according to Cochran13 to
nE84W$\ account for the effect of the cluster sampling. Ninety-five
`( Gk_VAa per cent confidence limits around age-standardized rates
z16++LKmM were calculated according to Breslow and Day.14 The strataspecific
^*OA%wg3=h data were weighted according to the 1996
<n{9pZ5. Australian Bureau of Statistics census data15 to reflect the
H<"j3qt cataract prevalence in the entire Victorian population.
<0m;|Ai'W Univariate analyses with Student’s t-tests and chi-squared
):@B1 yR tests were first employed to evaluate risk factors for unoperated
cS"6%:hQ cataract. Any factors with P < 0.10 were then fitted
aXagiz\; into a backwards stepwise logistic regression model. For the
kn.z8%^( Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
Fz% n!d final multivariate models, P < 0.05 was considered statistically
79DC]48M significant. Design effect was assessed through the use
C#R9Hlb of cluster-specific models and multivariate models. The
o%a$m9I design effect was assumed to be additive and an adjustment
p:jrqjLp made in the variance by adding the variance associated with
mN`a]L' the design effect prior to constructing the 95% confidence
T$e_ao| limits.
;Mz]uk RESULTS
*QX$Mo^E Study population
LFC k6 R A total of 3271 (83%) of the Melbourne residents, 403
c
LJCLKJ (90%) Melbourne nursing home residents, and 1473 (92%)
R)=<q]Ms rural residents participated. In general, non-participants did
K5$ y not differ from participants.16 The study population was
sIpK
@BQ' representative of the Victorian population and Australia as
`
T!O
)5 a whole.
g;pFT The Melbourne residents ranged in age from 40 to
I
zT%Kq 98 years (mean = 59) and 1511 (46%) were male. The
R+\5hI@ >i Melbourne nursing home residents ranged in age from 46 to
]%." 101 years (mean = 82) and 85 (21%) were men. The rural
- M]C-$ residents ranged in age from 40 to 103 years (mean = 60)
= 4If7 and 701 (47.5%) were men.
FD<~?- Prevalence of cataract and prior cataract surgery
]WG\+1x9 As would be expected, the rate of any cataract increases
E=y#~W dramatically with age (Table 1). The weighted rate of any
R?W8l5CIk cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
sYz:(hZS Although the rates varied somewhat between the three
_ AFgx8 strata, they were not significantly different as the 95% confidence
AXyuXB limits overlapped. The per cent of cataractous eyes
X7G6y|4;w with best-corrected visual acuity of less than 6/12 was 12.5%
2eNm2; (65/520) for cortical cataract, 18% for nuclear cataract
AA66^/t (97/534) and 14.4% (27/187) for PSC cataract. Cataract
&"BKue~q@p surgery also rose dramatically with age. The overall
$j:0*Z=> weighted rate of prior cataract surgery in Victoria was
_]\mh,} 3.79% (95% CL 2.97, 4.60) (Table 2).
Y/ `fPgE Risk factors for unoperated cataract
/4|qfF3 Cases of cataract that had not been removed were classified
qG;WX n as unoperated cataract. Risk factor analyses for unoperated
cIgF]My*D@ cataract were not performed with the nursing home residents
R\<^A~(Gl as information about risk factor exposure was not
GB-=
D
C6 available for this cohort. The following factors were assessed
aAX 8m in relation to unoperated cataract: age, sex, residence
HJ2]xe09 (urban/rural), language spoken at home (a measure of ethnic
eq"~b
y[Uq integration), country of birth, parents’ country of birth (a
Q/< $ (Y measure of ethnicity), years since migration, education, use
(Yx rZ_F'b of ophthalmic services, use of optometric services, private
? 0%lB=qQ health insurance status, duration of distance glasses use,
AVi|JY)> glaucoma, age-related maculopathy and employment status.
'?-GZ0oM In this cross sectional study it was not possible to assess the
_+UD>u{ level of visual acuity that would predict a patient’s having
F
Hv|6zUX cataract surgery, as visual acuity data prior to cataract
3&}wfK]
X surgery were not available.
*bZV4} The significant risk factors for unoperated cataract in univariate
~<|xS
analyses were related to: whether a participant had
K$rH{dUM ever seen an optometrist, seen an ophthalmologist or been
$
@^n3ZQ4 diagnosed with glaucoma; and participants’ employment
7Npz
{C{I status (currently employed) and age. These significant
Jk`A } factors were placed in a backwards stepwise logistic regression
vXyaOZ model. The factors that remained significantly related
/P,J);Y to unoperated cataract were whether participants had ever
d(h`bOjI seen an ophthalmologist, seen an optometrist and been
; LTc4t diagnosed with glaucoma. None of the demographic factors
6N]v9uXZ were associated with unoperated cataract in the multivariate
x5{ zGv.j model.
YncY_Hu The per cent of participants with unoperated cataract
xGz$M@f who said that they were dissatisfied or very dissatisfied with
x3)qK6,\ Operated and unoperated cataract in Australia 79
[
h%ci3 Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
V
k[m$ Age group Sex Urban Rural Nursing home Weighted total
m%m8002 (years) (%) (%) (%)
9!PJLI=D 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
U{HJNftdpm Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
r
lW 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
]_j{b)t Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
%<K`d 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
voCQ_~*)9 Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
'kPShZS$b 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
'%kk&&3' Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
a&|aK+^8; 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
NO"=\Zn6 Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
wn5CaP(]8 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
$--W,ov5j Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
`2Vc*R Age-standardized
6wfCC, 2 (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)
b=.Ikt+y aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
D.4=4"qMi their current vision was 30% (290/683), compared with 27%
=((#k DrN (26/95) of participants with prior cataract surgery (chisquared,
;E(%s=i
1 d.f. = 0.25, P = 0.62).
MHk\y2`/; Outcomes of cataract surgery
a";(C,:0 Two hundred and forty-nine eyes had undergone prior
(?D47^F & cataract surgery. Of these 249 operated eyes, 49 (20%) were
PO]z'LD left aphakic, 6 (2.4%) had anterior chamber intraocular
u-yQP@^H lenses and 194 (78%) had posterior chamber intraocular
>kd&>)9v lenses. The rate of capsulotomy in the eyes with intact
wSBDJvI posterior capsules was 36% (73/202). Fifteen per cent of
5L%A5C&| eyes (17/114) with a clear posterior capsule had bestcorrected
ZFY t[: visual acuity of less than 6/12 compared with 43%
;}ileLTl of eyes (6/14) with opaque capsules, and 15% of eyes
Y }aa6 (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
0sL
R5A P = 0.027).
b<~\IPY The percentage of eyes with best-corrected visual acuity
-P^ 6b( of 6/12 or better was 96% (302/314) for eyes without
rB~x]5TH cataract, 88% (1417/1609) for eyes with prevalent cataract
;3-5U&Axt and 85% (211/249) for eyes with operated cataract (chisquared,
ECWn/4Aws 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
U5[
xW operated eyes (11%) had visual acuities of less than 6/18
VZ5EV'D8! (moderate vision impairment) (Fig. 2). A cause of this
6V
KsX+sd moderate visual impairment (but not the only cause) in four
MD%_Z/NL (15%) eyes was secondary to cataract surgery. Three of these
!U/iY%NE four eyes had undergone intracapsular cataract extraction
al.~[T-O+ and the fourth eye had an opaque posterior capsule. No one
<b~KR8 had bilateral vision impairment as a result of their cataract
DDsU6RyN surgery.
M}k t q) DISCUSSION
wO;\,zU To our knowledge, this is the first paper to systematically
&9g4/c-?$ assess the prevalence of current cataract, previous cataract
SQ9s surgery, predictors of unoperated cataract and the outcomes
9
,=7Uh#7 of cataract surgery in a population-based sample. The Visual
`9}\kn-</8 Impairment Project is unique in that the sampling frame and
nw){}g high response rate have ensured that the study population is
i Tg?JoE2 representative of Australians aged 40 years and over. Therefore,
E5(\/;[*` these data can be used to plan age-related cataract
z=J%-Hq> services throughout Australia.
2It$ bz We found the rate of any cataract in those over the age
g}
7FR({b of 40 years to be 22%. Although relatively high, this rate is
6Lk<VpAa significantly less than was reported in a number of previous
Z6F>SL studies,2,4,6 with the exception of the Casteldaccia Eye
^tc2?T Study.5 However, it is difficult to compare rates of cataract
tkx
1iBW= between studies because of different methodologies and
@AYO )Y8 cataract definitions employed in the various studies, as well
P~$FgAV as the different age structures of the study populations.
l3dGe' Other studies have used less conservative definitions of
b0|q@!z> cataract, thus leading to higher rates of cataract as defined.
P{v>o,a. In most large epidemiologic studies of cataract, visual acuity
+ Bk"
khH has not been included in the definition of cataract.
SV*h9LL Therefore, the prevalence of cataract may not reflect the
(jv!q@@2C. actual need for cataract surgery in the community.
*NzHY;e 80 McCarty et al.
>tTNvb5 Table 2. Prevalence of previous cataract by age, gender and cohort
q|,cMPS3 Age group Gender Urban Rural Nursing home Weighted total
bkk1_X (years) (%) (%) (%)
$xqI3UaX 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
|_ ZD[v S Female 0.00 0.00 0.00 0.00 (
oxT..=- 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
VU6nu4 Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
Mr'P0^^ 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
2
]W"sT[ Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
pJkaP 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
mNS7/I\ Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
3~ITvH,`s 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
2K?~)q&t* Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
<%WN<T{q| 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
Sj?u^L8es} Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
bH+x `]{A Age-standardized
xszGao' (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)
*=UxX ]0y Figure 2. Visual acuity in eyes that had undergone cataract
ie4keVlXc surgery, n = 249. h, Presenting; j, best-corrected.
)X*?M?~\ Operated and unoperated cataract in Australia 81
5)X;q- The weighted prevalence of prior cataract surgery in the
_-/aMfyQ Visual Impairment Project (3.6%) was similar to the crude
!9GJ9ZEXM rate in the Beaver Dam Eye Study4 (3.1%), but less than the
O:02LHE crude rate in the Blue Mountains Eye Study6 (6.0%).
I,4t;4;Zk However, the age-standardized rate in the Blue Mountains
VrL==aTYXs Eye Study (standardized to the age distribution of the urban
jwsl"zL Visual Impairment Project cohort) was found to be less than
0Y rdu,c the Visual Impairment Project (standardized rate = 1.36%,
!e~Yp0gX# 95% CL 1.25, 1.47). The incidence of cataract surgery in
Ki#({~ Australia has exceeded population growth.1 This is due,
4R_Vi[
i perhaps, to advances in surgical techniques and lens
l5sBDiir% implants that have changed the risk–benefit ratio.
L<'8#J[_5 The Global Initiative for the Elimination of Avoidable
IT,d(UV_ Blindness, sponsored by the World Health Organization,
,(aOTFQS states that cataract surgical services should be provided that
q^{Z"ifL ‘have a high success rate in terms of visual outcome and
:00 #l]g0q improved quality of life’,17 although the ‘high success rate’ is
cG|)z<Z not defined. Population- and clinic-based studies conducted
=)Z!qjf1U in the United States have demonstrated marked improvement
En@] xvE in visual acuity following cataract surgery.18–20 We
)
V}q7\G~ found that 85% of eyes that had undergone cataract extraction
9G8n'jWyY had visual acuity of 6/12 or better. Previously, we have
$lkd9r1 shown that participants with prevalent cataract in this
RB]K? cohort are more likely to express dissatisfaction with their
>z0~!!YZ current vision than participants without cataract or participants
99Xbp P55 with prior cataract surgery.21 In a national study in the
e|wH5(V United States, researchers found that the change in patients’
T';<;6J** ratings of their vision difficulties and satisfaction with their
\Ol3kx| vision after cataract surgery were more highly related to
?3:OPP`s their change in visual functioning score than to their change
jYwv+EXg in visual acuity.19 Furthermore, improvement in visual function
X|.M9zIx has been shown to be associated with improvement in
; n2|pC^ overall quality of life.22
jRz2l`~7# A recent review found that the incidence of visually
wv,,#P significant posterior capsule opacification following
]+\@
_1<ZI cataract surgery to be greater than 25%.23 We found 36%
'BT}'qN capsulotomy in our population and that this was associated
x}TDb0V with visual acuity similar to that of eyes with a clear
\jn[kQ+pJ capsule, but significantly better than that of eyes with an
%hK?\Pg3=E opaque capsule.
&s!"pEZWck A number of studies have shown that the demand and
l ' ]d& timing of cataract surgery vary according to visual acuity,
]pLQ;7f7D degree of handicap and socioeconomic factors.8–10,24,25 We
NLDmZra have also shown previously that ophthalmologists are more
hq9b likely to refer a patient for cataract surgery if the patient is
7 q<UJIf employed and less likely to refer a nursing home resident.7
W5-p0,?[6 In the Visual Impairment Project, we did not find that any
'e-Nt&; particular subgroup of the population was at greater risk of
gF%lwq having unoperated cataract. Universal access to health care
0pYz8OB in Australia may explain the fact that people without
y(|6` Medicare are more likely to delay cataract operations in the
k/nOz* USA,8 but not having private health insurance is not associated
K5(?6hr; with unoperated cataract in Australia.
/U<-N'| In summary, cataract is a significant public health problem
;VS;),h/ in that one in four people in their 80s will have had cataract
5VWXUNe@_q surgery. The importance of age-related cataract surgery will
84P^7[YX> increase further with the ageing of the population: the
".| 9h number of people over age 60 years is expected to double in
KdFQlQaj the next 20 years. Cataract surgery services are well
zW%-Z6%D accessed by the Victorian population and the visual outcomes
?/"@WP9 of cataract surgery have been shown to be very good.
P*/p x4;6 These data can be used to plan for age-related cataract
.hgc1 surgical services in Australia in the future as the need for
:c,\8n cataract extractions increases.
kgK7 T ACKNOWLEDGEMENTS
xk86?2b{) The Visual Impairment Project was funded in part by grants
~! ]FF}6 from the Victorian Health Promotion Foundation, the
mBc;^8I?23 National Health and Medical Research Council, the Ansell
p<'mc|hGq Ophthalmology Foundation, the Dorothy Edols Estate and
}"fP,:n"KN the Jack Brockhoff Foundation. Dr McCarty is the recipient
%-]j;'6}cX of a Wagstaff Fellowship in Ophthalmology from the Royal
1*
?
IDYB Victorian Eye and Ear Hospital.
HeGGAjc REFERENCES
>;o^qi_$ 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
e }/c`7M
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