ABSTRACT
zMbz_22* Purpose: To quantify the prevalence of cataract, the outcomes
+X4/l"
| of cataract surgery and the factors related to
B,avI&7M;S unoperated cataract in Australia.
&C6Z{.3V Methods: Participants were recruited from the Visual
V^E.9fs, Impairment Project: a cluster, stratified sample of more than
q&0I7OV 5000 Victorians aged 40 years and over. At examination
@`H47@e sites interviews, clinical examinations and lens photography
> ?<C+ZHh were performed. Cataract was defined in participants who
* vW#XDx had: had previous cataract surgery, cortical cataract greater
q}MPl 2 than 4/16, nuclear greater than Wilmer standard 2, or
uBqZ62{G posterior subcapsular greater than 1 mm2.
4pC.mRu
0 Results: The participant group comprised 3271 Melbourne
}.74w0~0^ residents, 403 Melbourne nursing home residents and 1473
VmTPE5d rural residents.The weighted rate of any cataract in Victoria
-1 <*mbb0 was 21.5%. The overall weighted rate of prior cataract
eZk4$
y surgery was 3.79%. Two hundred and forty-nine eyes had
XXA1%Lw% had prior cataract surgery. Of these 249 procedures, 49
$pGdGV\H (20%) were aphakic, 6 (2.4%) had anterior chamber
|Y|g T*v intraocular lenses and 194 (78%) had posterior chamber
j_Qkw ? intraocular lenses.Two hundred and eleven of these operated
8nQj
D<- eyes (85%) had best-corrected visual acuity of 6/12 or
8e*1L:oB! better, the legal requirement for a driver’s license.Twentyseven
m[%*O#_ (11%) had visual acuity of less than 6/18 (moderate
OjRJyhzS* vision impairment). Complications of cataract surgery
64w4i)?eM[ caused reduced vision in four of the 27 eyes (15%), or 1.9%
L2
^-t7 of operated eyes. Three of these four eyes had undergone
6im!v<1Qx intracapsular cataract extraction and the fourth eye had an
j&
~`wGM opaque posterior capsule. No one had bilateral vision
R1lC_G] impairment as a result of cataract surgery. Surprisingly, no
{
B,r particular demographic factors (such as age, gender, rural
#I] ^Wo
residence, occupation, employment status, health insurance
FEzjP$ status, ethnicity) were related to the presence of unoperated
#CY Dh8X<i cataract.
7GVI={b Conclusions: Although the overall prevalence of cataract is
6
x 8P}? quite high, no particular subgroup is systematically underserviced
[/iT D=
O, in terms of cataract surgery. Overall, the results of
GfMCHs cataract surgery are very good, with the majority of eyes
Z<^TO1xs9B achieving driving vision following cataract extraction.
b w2KD7 Key words: cataract extraction, health planning, health
Fo@cz"
% services accessibility, prevalence
4<{]_S6"0y INTRODUCTION
F#^<t$5t Cataract is the leading cause of blindness worldwide and, in
do>,ELS+m Australia, cataract extractions account for the majority of all
jJOs`'~Q\ ophthalmic procedures.1 Over the period 1985–94, the rate
m_pqU(sP of cataract surgery in Australia was twice as high as would be
svTKt%6X expected from the growth in the elderly population.1
r(Vz( Although there have been a number of studies reporting
O<EFm}Ae the prevalence of cataract in various populations,2–6 there is
Hz6tk9;w little information about determinants of cataract surgery in
yoc;`hO- the population. A previous survey of Australian ophthalmologists
-4IHs=`;I showed that patient concern and lifestyle, rather
4`M7
3k0 than visual acuity itself, are the primary factors for referral
Tb@r@j:V for cataract surgery.7 This supports prior research which has
znxP.=GB shown that visual acuity is not a strong predictor of need for
2@~hELkk/E cataract surgery.8,9 Elsewhere, socioeconomic status has
xS>d$)rIj been shown to be related to cataract surgery rates.10
_b)=ERBbCo To appropriately plan health care services, information is
!um~P needed about the prevalence of age-related cataract in the
^KRe(
community as well as the factors associated with cataract
R5KOai! surgery. The purpose of this study is to quantify the prevalence
v%2 @M of any cataract in Australia, to describe the factors
lH#C:n related to unoperated cataract in the community and to
.%x%b6EI describe the visual outcomes of cataract surgery.
Vhi4_~W3j] METHODS
rTmVHt Study population
^_rBEyz@ Details about the study methodology for the Visual
R|u2ga~ Impairment Project have been published previously.11
|@*3
nb8 Briefly, cluster sampling within three strata was employed to
BGOajYD recruit subjects aged 40 years and over to participate.
hq|I%>y Within the Melbourne Statistical Division, nine pairs of
A6Vb'Gqv{ census collector districts were randomly selected. Fourteen
u"s@eN
nursing homes within a 5 km radius of these nine test sites
q4y sTm were randomly chosen to recruit nursing home residents.
s'4%ZE2Dr Clinical and Experimental Ophthalmology (2000) 28, 77–82
FD[o94`% Original Article
=73aME} Operated and unoperated cataract in Australia
qe<xH#6 Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
&ra2(S45 Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
uy'qIq n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
#i'wDvhol Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au ]VcuD05"C 78 McCarty et al.
R}E$SmFg Finally, four pairs of census collector districts in four rural
N#<X"&-_# Victorian communities were randomly selected to recruit rural
\TS.9 >\ residents. A household census was conducted to identify
4L _AhX7 eligible residents aged 40 years and over who had been a
C-sFTf7 resident at that address for at least 6 months. At the time of
ZuNUha&a the household census, basic information about age, sex,
u/.# zn@9h country of birth, language spoken at home, education, use of
Q79WGW corrective spectacles and use of eye care services was collected.
,:6.Gi)| Eligible residents were then invited to attend a local
@>q4hYF examination site for a more detailed interview and examination.
FG5YZrONx The study protocol was approved by the Royal Victorian
Uo
0[ZsFD Eye and Ear Hospital Human Research Ethics Committee.
W_bA
.zT{ Assessment of cataract
qNX+!Y}y A standardized ophthalmic examination was performed after
'>
:%n pupil dilatation with one drop of 10% phenylephrine
08_<G`r hydrochloride. Lens opacities were graded clinically at the
#}+_Hy time of the examination and subsequently from photos using
C
{G647 the Wilmer cataract photo-grading system.12 Cortical and
,8)aKy posterior subcapsular (PSC) opacities were assessed on
8E|FFHNK<2 retroillumination and measured as the proportion (in 1/16)
\F9HsR6 of pupil circumference occupied by opacity. For this analysis,
q
rF:=?`E cortical cataract was defined as 4/16 or greater opacity,
&\W5|*`x- PSC cataract was defined as opacity equal to or greater than
$AF,4Ir-b+ 1 mm2 and nuclear cataract was defined as opacity equal to
F#Bi*YY or greater than Wilmer standard 2,12 independent of visual
o@qI!?p& acuity. Examples of the minimum opacities defined as cortical,
!|-:"hE1h nuclear and PSC cataract are presented in Figure 1.
nnuJY$O;M Bilateral congenital cataracts or cataracts secondary to
F-<c.
0;6 intraocular inflammation or trauma were excluded from the
',s{N9 analysis. Two cases of bilateral secondary cataract and eight
.#_g.0< cases of bilateral congenital cataract were excluded from the
_Kv;hR> analyses.
ar:qCq$\ A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
t]6
4= Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
lTZcbaO?] height set to an incident angle of 30° was used for examinations.
kYu"`_n} Ektachrome® 200 ASA colour slide film (Eastman
tRXR/;3O Kodak Company, Rochester, NY, USA) was used to photograph
p;rT#R&6> the nuclear opacities. The cortical opacities were
k-8$43 photographed with an Oxford® retroillumination camera
V3[>^ZCA (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
^fhkWx 4i film (Eastman Kodak). Photographs were graded separately
j12khp? by two research assistants and discrepancies were adjudicated
qViolmDz by an independent reviewer. Any discrepancies
2@f?yh0 between the clinical grades and the photograph grades were
t**o<p#)f resolved. Except in cases where photographs were missing,
FQw@@ the photograph grades were used in the analyses. Photograph
S*a_ grades were available for 4301 (84%) for cortical
h9j/mUwV cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
Zl7m:b2M for PSC cataract. Cataract status was classified according to
H:`[$
^ the severity of the opacity in the worse eye.
S@vLh=65 Assessment of risk factors
<'<{|$Pw A standardized questionnaire was used to obtain information
WHvxBd about education, employment and ethnic background.11
Hh0a\%! Specific information was elicited on the occurrence, duration
Hbi2amfBu and treatment of a number of medical conditions,
-,}p
pTG including ocular trauma, arthritis, diabetes, gout, hypertension
"~aCW~ and mental illness. Information about the use, dose and
TkV*^j5 duration of tobacco, alcohol, analgesics and steriods were
16n8[U! collected, and a food frequency questionnaire was used to
\!,qXfTMB determine current consumption of dietary sources of antioxidants
kV3Z
t@+ and use of vitamin supplements.
t"]~e" Data management and statistical analysis
Zv)x-48 Data were collected either by direct computer entry with a
x@480r questionnaire programmed in Paradox© (Carel Corporation,
gTwxmp., Ottawa, Canada) with internal consistency checks, or
tO]`
I- on self-coding forms. Open-ended responses were coded at
i-_ * 5%A a later time. Data that were entered on the self-coded forms
9?#L/ were entered into a computer with double data entry and
-P|st;?# reconciliation of any inconsistencies. Data range and consistency
8^%Nl `_2B checks were performed on the entire data set.
x"QZ}28(t SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
T?'Vb employed for statistical analyses.
XB'PEvh8 Ninety-five per cent confidence limits around the agespecific
6_h'0~3?` rates were calculated according to Cochran13 to
GV T[)jS account for the effect of the cluster sampling. Ninety-five
p!xCNZ(m per cent confidence limits around age-standardized rates
`@07n]KB were calculated according to Breslow and Day.14 The strataspecific
CDTM<0`% data were weighted according to the 1996
8RJ^e[?o( Australian Bureau of Statistics census data15 to reflect the
0O:')R& cataract prevalence in the entire Victorian population.
8Mf{6&F= Univariate analyses with Student’s t-tests and chi-squared
8Cw+<A* tests were first employed to evaluate risk factors for unoperated
vMB`TpZ cataract. Any factors with P < 0.10 were then fitted
,aBo
p# into a backwards stepwise logistic regression model. For the
l4+Bs!i` Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
^N\$oV$ final multivariate models, P < 0.05 was considered statistically
M$0-!$RY significant. Design effect was assessed through the use
t/TWLhx/ of cluster-specific models and multivariate models. The
aX$Q}mgb design effect was assumed to be additive and an adjustment
yhpeP made in the variance by adding the variance associated with
at-+%e
the design effect prior to constructing the 95% confidence
`oq][| limits.
.!pr0/9B RESULTS
@ysc?4% q Study population
Ob#d;F A total of 3271 (83%) of the Melbourne residents, 403
_^5OoE"}! (90%) Melbourne nursing home residents, and 1473 (92%)
y
Hk}'YP rural residents participated. In general, non-participants did
2aR<xcSg not differ from participants.16 The study population was
E kv
Tl- representative of the Victorian population and Australia as
e(~9JP9
a whole.
iUua!uC The Melbourne residents ranged in age from 40 to
=h
Lw1~ 98 years (mean = 59) and 1511 (46%) were male. The
zG. \xmp Melbourne nursing home residents ranged in age from 46 to
y`|86`
Y 101 years (mean = 82) and 85 (21%) were men. The rural
zv8AvNDK residents ranged in age from 40 to 103 years (mean = 60)
miTySY6^ and 701 (47.5%) were men.
'fIoN% Prevalence of cataract and prior cataract surgery
qLYz-P'ik As would be expected, the rate of any cataract increases
p-Jp/*R5 dramatically with age (Table 1). The weighted rate of any
Sr#\5UDS cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
L]kd.JJvy Although the rates varied somewhat between the three
-+ha4JOB strata, they were not significantly different as the 95% confidence
9k.5'# limits overlapped. The per cent of cataractous eyes
Id}/(Pkq with best-corrected visual acuity of less than 6/12 was 12.5%
rn9n _) (65/520) for cortical cataract, 18% for nuclear cataract
@?vC4+' (97/534) and 14.4% (27/187) for PSC cataract. Cataract
{TL.2 surgery also rose dramatically with age. The overall
B8~JUGD weighted rate of prior cataract surgery in Victoria was
/f}!G 3.79% (95% CL 2.97, 4.60) (Table 2).
H _0F:e Risk factors for unoperated cataract
SIridZ*% Cases of cataract that had not been removed were classified
90[6PSXk as unoperated cataract. Risk factor analyses for unoperated
_@5|r|P> cataract were not performed with the nursing home residents
1)o6jGQ as information about risk factor exposure was not
{Z,_/@}N available for this cohort. The following factors were assessed
XU y[l in relation to unoperated cataract: age, sex, residence
m!K`?P]:N (urban/rural), language spoken at home (a measure of ethnic
9?XQB%44 integration), country of birth, parents’ country of birth (a
;p+[R+ ) measure of ethnicity), years since migration, education, use
jP{&U&!i of ophthalmic services, use of optometric services, private
\47djmG- health insurance status, duration of distance glasses use,
YO'aX glaucoma, age-related maculopathy and employment status.
2O
2HmL In this cross sectional study it was not possible to assess the
XkPE%m_5D level of visual acuity that would predict a patient’s having
{sfA$ d0 cataract surgery, as visual acuity data prior to cataract
ZuFcJ?8i surgery were not available.
-tZ~&
1" The significant risk factors for unoperated cataract in univariate
k-Yli21-/| analyses were related to: whether a participant had
'^.`mT'P ever seen an optometrist, seen an ophthalmologist or been
,g pZz$Ef( diagnosed with glaucoma; and participants’ employment
n_
4 r'w status (currently employed) and age. These significant
]9N&I/- factors were placed in a backwards stepwise logistic regression
bp!Jjct model. The factors that remained significantly related
M#_|WL~ to unoperated cataract were whether participants had ever
s IFE:/1, seen an ophthalmologist, seen an optometrist and been
^)(-7H diagnosed with glaucoma. None of the demographic factors
.P
<3+ were associated with unoperated cataract in the multivariate
k8?G%/TD model.
4[(NxXH8M The per cent of participants with unoperated cataract
g/FZ?Wo who said that they were dissatisfied or very dissatisfied with
84WX I#BH Operated and unoperated cataract in Australia 79
[!De|,u(^ Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
6w=`0r3hy Age group Sex Urban Rural Nursing home Weighted total
&7i&"TNptP (years) (%) (%) (%)
?-zuy
US 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
Z}TLk^_[ Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
$AT@r"
50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
?ac4GA( Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
9O- 2 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
&JXb) W Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
m8=n `XI 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
Cs_&BSs Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
^?$,sS
;Q 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
xbBqR_H_ Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
fZezDm(Q 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
D#G%WT/" Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
W|D
kq Age-standardized
hJ$9Hb (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
{"+M%%`*# aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
.%s
U)$bH their current vision was 30% (290/683), compared with 27%
jM&di (26/95) of participants with prior cataract surgery (chisquared,
Lo~;pvv 1 d.f. = 0.25, P = 0.62).
[lg!* Outcomes of cataract surgery
":_II[FPY Two hundred and forty-nine eyes had undergone prior
kDE-GX"Y cataract surgery. Of these 249 operated eyes, 49 (20%) were
i1|>JM[V left aphakic, 6 (2.4%) had anterior chamber intraocular
!(rAI lenses and 194 (78%) had posterior chamber intraocular
@uH!n~QV lenses. The rate of capsulotomy in the eyes with intact
|)+
SG>- posterior capsules was 36% (73/202). Fifteen per cent of
Y@`uBB[ eyes (17/114) with a clear posterior capsule had bestcorrected
HMCLJ/ visual acuity of less than 6/12 compared with 43%
Xva(R<W7d< of eyes (6/14) with opaque capsules, and 15% of eyes
.
P$m?p# (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
=nGFLH6) P = 0.027).
B=!!R]dxA The percentage of eyes with best-corrected visual acuity
]*#i_dho7 of 6/12 or better was 96% (302/314) for eyes without
=3.dgtH cataract, 88% (1417/1609) for eyes with prevalent cataract
"_q~S$i^ and 85% (211/249) for eyes with operated cataract (chisquared,
9h amxi 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
lN#j%0MaUo operated eyes (11%) had visual acuities of less than 6/18
/)6T>/ (moderate vision impairment) (Fig. 2). A cause of this
M
bWby' moderate visual impairment (but not the only cause) in four
~;3yjO)l?) (15%) eyes was secondary to cataract surgery. Three of these
#NW+t|E four eyes had undergone intracapsular cataract extraction
#4JMb#q0E and the fourth eye had an opaque posterior capsule. No one
*S ag had bilateral vision impairment as a result of their cataract
zr/v .$< surgery.
Hu"$)V DISCUSSION
t1Fqq4wRi To our knowledge, this is the first paper to systematically
;OlnIxH(W assess the prevalence of current cataract, previous cataract
[)Nt;|U surgery, predictors of unoperated cataract and the outcomes
.; F<X\_ of cataract surgery in a population-based sample. The Visual
h mRmU{(Y Impairment Project is unique in that the sampling frame and
@3.Z>KONx high response rate have ensured that the study population is
'2.ey33V representative of Australians aged 40 years and over. Therefore,
J\y^T3
Z these data can be used to plan age-related cataract
`;j1H<L services throughout Australia.
TcaW'&(K We found the rate of any cataract in those over the age
LP"g(D2'n of 40 years to be 22%. Although relatively high, this rate is
g{V(WyT@ significantly less than was reported in a number of previous
Pvc)-A studies,2,4,6 with the exception of the Casteldaccia Eye
^
8 }P_ Study.5 However, it is difficult to compare rates of cataract
q`1tUd 4G between studies because of different methodologies and
}_nBe
gv cataract definitions employed in the various studies, as well
y||
n9 as the different age structures of the study populations.
7Mh'x:p Other studies have used less conservative definitions of
peVY2\1>R cataract, thus leading to higher rates of cataract as defined.
n+8YTjd In most large epidemiologic studies of cataract, visual acuity
ZWCsrV*; has not been included in the definition of cataract.
=FzmifTc Therefore, the prevalence of cataract may not reflect the
9
Zo s; actual need for cataract surgery in the community.
xw8k<` 80 McCarty et al.
}!iopu Table 2. Prevalence of previous cataract by age, gender and cohort
2H`r:x<Z- Age group Gender Urban Rural Nursing home Weighted total
nGVr\u9z (years) (%) (%) (%)
@ym:@<D 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
I0F[Z\U Female 0.00 0.00 0.00 0.00 (
k{f1q>gd 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
_/:- -Z Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
u0wu\ 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
Qr
R+3kxM Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
(')t>B1Z 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
%72# tY Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
lz`\Q6rZ 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
D\G 8p; Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
C/!P&`<6 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
1Lf - Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
c^_+<C-F Age-standardized
q}_8iDO6 (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)
gkK(
7=r% Figure 2. Visual acuity in eyes that had undergone cataract
^
h_rE
|c surgery, n = 249. h, Presenting; j, best-corrected.
:30daKo
Operated and unoperated cataract in Australia 81
I_B%F#X) The weighted prevalence of prior cataract surgery in the
&DQ_qOKD Visual Impairment Project (3.6%) was similar to the crude
3x(Y+
ymP rate in the Beaver Dam Eye Study4 (3.1%), but less than the
"A[.7 w crude rate in the Blue Mountains Eye Study6 (6.0%).
-qSGa;PJ However, the age-standardized rate in the Blue Mountains
fbI5!i#lz Eye Study (standardized to the age distribution of the urban
-wUT@a Visual Impairment Project cohort) was found to be less than
H
E*^!2f the Visual Impairment Project (standardized rate = 1.36%,
c
CjN8< 95% CL 1.25, 1.47). The incidence of cataract surgery in
Fp B3SJ6 B Australia has exceeded population growth.1 This is due,
+v%+E{F$+ perhaps, to advances in surgical techniques and lens
c@lF*"4 implants that have changed the risk–benefit ratio.
|s#,^SJ0 The Global Initiative for the Elimination of Avoidable
Z2;~{$&M+ Blindness, sponsored by the World Health Organization,
D{7sfkcJ states that cataract surgical services should be provided that
#x;d+Q@ ‘have a high success rate in terms of visual outcome and
eLH=PDdO improved quality of life’,17 although the ‘high success rate’ is
pl}W|kW} not defined. Population- and clinic-based studies conducted
0}Kyj"-3 in the United States have demonstrated marked improvement
>8NUji2I in visual acuity following cataract surgery.18–20 We
T2?.o.&u found that 85% of eyes that had undergone cataract extraction
#m{F*(% had visual acuity of 6/12 or better. Previously, we have
asW
W@E shown that participants with prevalent cataract in this
WM9({BZ cohort are more likely to express dissatisfaction with their
OZKZv, current vision than participants without cataract or participants
'0Q/oU with prior cataract surgery.21 In a national study in the
e[Z-&' United States, researchers found that the change in patients’
eiA$) rzy ratings of their vision difficulties and satisfaction with their
TPj,4&| vision after cataract surgery were more highly related to
B0g?!.#23 their change in visual functioning score than to their change
{iQ4jJ`n in visual acuity.19 Furthermore, improvement in visual function
|]HA@7B has been shown to be associated with improvement in
-Zg.o$ overall quality of life.22
| @B|o- A recent review found that the incidence of visually
6m:$RW significant posterior capsule opacification following
;iN[du cataract surgery to be greater than 25%.23 We found 36%
'^Q$:P{G? capsulotomy in our population and that this was associated
z+c8G with visual acuity similar to that of eyes with a clear
Yru,YA
capsule, but significantly better than that of eyes with an
6ZXRb opaque capsule.
~A(^< A number of studies have shown that the demand and
V_4=0( timing of cataract surgery vary according to visual acuity,
R<r,&X?m degree of handicap and socioeconomic factors.8–10,24,25 We
$m-@ICG# have also shown previously that ophthalmologists are more
dA#'HMh@ likely to refer a patient for cataract surgery if the patient is
p8iKZI]g employed and less likely to refer a nursing home resident.7
nx!+:P , In the Visual Impairment Project, we did not find that any
H@|m^1 particular subgroup of the population was at greater risk of
Eb&=$4c= having unoperated cataract. Universal access to health care
e[QEOx/-h2 in Australia may explain the fact that people without
DnCIfda2g Medicare are more likely to delay cataract operations in the
.;
dI&0Z USA,8 but not having private health insurance is not associated
1_mqPMm with unoperated cataract in Australia.
Q+IB&LdE In summary, cataract is a significant public health problem
QwnqysNx4 in that one in four people in their 80s will have had cataract
#Fh:z4 surgery. The importance of age-related cataract surgery will
S<I9`k G increase further with the ageing of the population: the
'qoaMJxN` number of people over age 60 years is expected to double in
1#XZVp;M the next 20 years. Cataract surgery services are well
.sZ"|j9m accessed by the Victorian population and the visual outcomes
ZQsVSz( 1 of cataract surgery have been shown to be very good.
@f#6Nu These data can be used to plan for age-related cataract
c`UizZ surgical services in Australia in the future as the need for
dp }z
G+ cataract extractions increases.
<,t6A?YoMP ACKNOWLEDGEMENTS
QOv@rP/ The Visual Impairment Project was funded in part by grants
`Js"*[z from the Victorian Health Promotion Foundation, the
%\1W0%w National Health and Medical Research Council, the Ansell
MVDy|i4 Ophthalmology Foundation, the Dorothy Edols Estate and
PSU}fo the Jack Brockhoff Foundation. Dr McCarty is the recipient
cE*d(g of a Wagstaff Fellowship in Ophthalmology from the Royal
!w
o Victorian Eye and Ear Hospital.
C|S~>4` REFERENCES
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