ABSTRACT
p=13
tQS< Purpose: To quantify the prevalence of cataract, the outcomes
EY+/
foP of cataract surgery and the factors related to
(S<Z@y+d unoperated cataract in Australia.
tFj[>_d7 Methods: Participants were recruited from the Visual
{9mXJu$cc Impairment Project: a cluster, stratified sample of more than
`wGP31Y. 5000 Victorians aged 40 years and over. At examination
Ei$?]~
& sites interviews, clinical examinations and lens photography
ahJ-T@ were performed. Cataract was defined in participants who
^lw0}
i had: had previous cataract surgery, cortical cataract greater
[v0[,K than 4/16, nuclear greater than Wilmer standard 2, or
r [NI#wW posterior subcapsular greater than 1 mm2.
BeR7LV Results: The participant group comprised 3271 Melbourne
#k}x} rn<' residents, 403 Melbourne nursing home residents and 1473
_U
Q|I|V# rural residents.The weighted rate of any cataract in Victoria
322)r$!" was 21.5%. The overall weighted rate of prior cataract
k 'CM^,F& surgery was 3.79%. Two hundred and forty-nine eyes had
fC4#b?Q had prior cataract surgery. Of these 249 procedures, 49
lhk=yVG3 (20%) were aphakic, 6 (2.4%) had anterior chamber
ox|K2A intraocular lenses and 194 (78%) had posterior chamber
=P}BAJ intraocular lenses.Two hundred and eleven of these operated
mQ$a^28=qR eyes (85%) had best-corrected visual acuity of 6/12 or
\jR('5DcB better, the legal requirement for a driver’s license.Twentyseven
[\_#n5 (11%) had visual acuity of less than 6/18 (moderate
/7`fg0A vision impairment). Complications of cataract surgery
^Fop/\E caused reduced vision in four of the 27 eyes (15%), or 1.9%
- WEEnwZ of operated eyes. Three of these four eyes had undergone
wO-](3A-8P intracapsular cataract extraction and the fourth eye had an
g %ZKn opaque posterior capsule. No one had bilateral vision
s:p6oEQ=J impairment as a result of cataract surgery. Surprisingly, no
)NjxKSiU@ particular demographic factors (such as age, gender, rural
vG2&qjY1 residence, occupation, employment status, health insurance
U%PII>s'# status, ethnicity) were related to the presence of unoperated
fR^
aFT cataract.
Yw!(]8PYdU Conclusions: Although the overall prevalence of cataract is
?|$IZ9 quite high, no particular subgroup is systematically underserviced
<+r<3ZBA in terms of cataract surgery. Overall, the results of
$D
%[}[2 cataract surgery are very good, with the majority of eyes
RZL
:k;}5 achieving driving vision following cataract extraction.
r5s$#,O/&Q Key words: cataract extraction, health planning, health
'P`L?/_3 services accessibility, prevalence
)=9EShz! INTRODUCTION
.ou#BWav/ Cataract is the leading cause of blindness worldwide and, in
USrBi[_ci\ Australia, cataract extractions account for the majority of all
i0jR~vF
{B ophthalmic procedures.1 Over the period 1985–94, the rate
>cdxe3I\ of cataract surgery in Australia was twice as high as would be
y5!fbmf expected from the growth in the elderly population.1
2 y;J 11\ Although there have been a number of studies reporting
[W*xPXr* the prevalence of cataract in various populations,2–6 there is
nyRQ/.3 little information about determinants of cataract surgery in
H}f}Y8J{ the population. A previous survey of Australian ophthalmologists
? 3'O showed that patient concern and lifestyle, rather
Up*.z\|'y than visual acuity itself, are the primary factors for referral
2sXNVo8`w" for cataract surgery.7 This supports prior research which has
v "
Yo shown that visual acuity is not a strong predictor of need for
#CcC& I
:c cataract surgery.8,9 Elsewhere, socioeconomic status has
O)EA2`)E been shown to be related to cataract surgery rates.10
m,1Hlp To appropriately plan health care services, information is
^:Hx . needed about the prevalence of age-related cataract in the
gOSFvH8FU community as well as the factors associated with cataract
r,FPTf
surgery. The purpose of this study is to quantify the prevalence
&X`zk of any cataract in Australia, to describe the factors
-&UP[Mq related to unoperated cataract in the community and to
=TcT` ](o describe the visual outcomes of cataract surgery.
#J_+
SL[ METHODS
%+F%C=GqI Study population
+yO^,{8SE Details about the study methodology for the Visual
4eh~/o&h Impairment Project have been published previously.11
Q}qw`L1 Briefly, cluster sampling within three strata was employed to
piPx8jT`F recruit subjects aged 40 years and over to participate.
.9'bi#:Cw Within the Melbourne Statistical Division, nine pairs of
n5e1ky*9w census collector districts were randomly selected. Fourteen
1v2pPUH\ nursing homes within a 5 km radius of these nine test sites
^{+,j}V_H were randomly chosen to recruit nursing home residents.
]\ DIJ>JZ Clinical and Experimental Ophthalmology (2000) 28, 77–82
K H&o`U(} Original Article
<{"Jy)Uf Operated and unoperated cataract in Australia
-s5>GwZt Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
fHc/5uYW Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
Hi5}s
n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
,2*x4Gycb Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au 23_\UTM}1 78 McCarty et al.
_ giZ'&l! Finally, four pairs of census collector districts in four rural
L2P#5B!S Victorian communities were randomly selected to recruit rural
4Y!_tZ> residents. A household census was conducted to identify
@9ndr$t eligible residents aged 40 years and over who had been a
oD?c]}3 resident at that address for at least 6 months. At the time of
fJ8Q\lb<_ the household census, basic information about age, sex,
lQ!)0F country of birth, language spoken at home, education, use of
UP?]5x> corrective spectacles and use of eye care services was collected.
\Ng|bWR>LQ Eligible residents were then invited to attend a local
o%1dbbh examination site for a more detailed interview and examination.
XeRbn The study protocol was approved by the Royal Victorian
1 ^q~NYTK Eye and Ear Hospital Human Research Ethics Committee.
KH_~DZU*5 Assessment of cataract
\
pJB
BG A standardized ophthalmic examination was performed after
pjaDtNb pupil dilatation with one drop of 10% phenylephrine
sPoH12?AL hydrochloride. Lens opacities were graded clinically at the
5L% \rH&N time of the examination and subsequently from photos using
PY{])z3N the Wilmer cataract photo-grading system.12 Cortical and
<-avC/M$d posterior subcapsular (PSC) opacities were assessed on
+,$ SZ O] retroillumination and measured as the proportion (in 1/16)
6B .x= of pupil circumference occupied by opacity. For this analysis,
+D&aE$< cortical cataract was defined as 4/16 or greater opacity,
E%tGwbi7 PSC cataract was defined as opacity equal to or greater than
AQR/nWwx 1 mm2 and nuclear cataract was defined as opacity equal to
mO|YX/> or greater than Wilmer standard 2,12 independent of visual
co-dq\P acuity. Examples of the minimum opacities defined as cortical,
L28DBj E)A nuclear and PSC cataract are presented in Figure 1.
B!X;T9^d Bilateral congenital cataracts or cataracts secondary to
,ag:w<km intraocular inflammation or trauma were excluded from the
6Rcl HU analysis. Two cases of bilateral secondary cataract and eight
;{% R[M' cases of bilateral congenital cataract were excluded from the
u:[vqlU analyses.
X6`F<H` A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
kl/eJN'S Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
jXu)%< height set to an incident angle of 30° was used for examinations.
8a}et8df: Ektachrome® 200 ASA colour slide film (Eastman
brXLx+H8 Kodak Company, Rochester, NY, USA) was used to photograph
KDQqN]rg the nuclear opacities. The cortical opacities were
E!_mXjlPc photographed with an Oxford® retroillumination camera
>3\($<YDZM (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
c@&-c [k^W film (Eastman Kodak). Photographs were graded separately
IA$)E
by two research assistants and discrepancies were adjudicated
l%^VBv>
2 by an independent reviewer. Any discrepancies
n9p_D between the clinical grades and the photograph grades were
+q N
X/F resolved. Except in cases where photographs were missing,
5OS|Vp||b the photograph grades were used in the analyses. Photograph
m.
|__L grades were available for 4301 (84%) for cortical
9f/RD?(1O cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
J/ !Mt for PSC cataract. Cataract status was classified according to
1B#Z<p the severity of the opacity in the worse eye.
WBIJ9e
2~ Assessment of risk factors
miCW(mbO8 A standardized questionnaire was used to obtain information
|4lrVYG^K about education, employment and ethnic background.11
.PHz
Specific information was elicited on the occurrence, duration
pD)$O} and treatment of a number of medical conditions,
V_.n G; including ocular trauma, arthritis, diabetes, gout, hypertension
+2WvGRC and mental illness. Information about the use, dose and
wy)I6`v duration of tobacco, alcohol, analgesics and steriods were
SA1|7 collected, and a food frequency questionnaire was used to
.&Rj2d determine current consumption of dietary sources of antioxidants
g
OnVN6 and use of vitamin supplements.
kCoTz"Z-
Data management and statistical analysis
W\W|v?r Data were collected either by direct computer entry with a
M1sR+e$" questionnaire programmed in Paradox© (Carel Corporation,
| D?lF Ottawa, Canada) with internal consistency checks, or
Q8^fgI | on self-coding forms. Open-ended responses were coded at
w)u6J, a later time. Data that were entered on the self-coded forms
Z\@m_/g were entered into a computer with double data entry and
EP;TfWc}1 reconciliation of any inconsistencies. Data range and consistency
AlQE;4yX checks were performed on the entire data set.
H%AF, SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
AzwG_XgM) employed for statistical analyses.
^9 g+\W Ninety-five per cent confidence limits around the agespecific
T{VdlgL rates were calculated according to Cochran13 to
q!5 *)nw" account for the effect of the cluster sampling. Ninety-five
g'F{;Ur per cent confidence limits around age-standardized rates
$G_,$U! were calculated according to Breslow and Day.14 The strataspecific
B<`'h data were weighted according to the 1996
9w%|Nk>=> Australian Bureau of Statistics census data15 to reflect the
YjV-70' cataract prevalence in the entire Victorian population.
4IW7^Pq`P Univariate analyses with Student’s t-tests and chi-squared
pu"`*NL tests were first employed to evaluate risk factors for unoperated
D)u 9Y cataract. Any factors with P < 0.10 were then fitted
]B;\?Tim into a backwards stepwise logistic regression model. For the
%Q0J$eC Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
K1F,M9 0] final multivariate models, P < 0.05 was considered statistically
Hvm+Tr2@ significant. Design effect was assessed through the use
<}^W9>u< of cluster-specific models and multivariate models. The
L;n
2,b design effect was assumed to be additive and an adjustment
c]y"5;V8 made in the variance by adding the variance associated with
6__#n` the design effect prior to constructing the 95% confidence
A=v^`a03I limits.
}Z|uLXaz RESULTS
T%%+v#+ Study population
f-V8/ A total of 3271 (83%) of the Melbourne residents, 403
}WN0L?h.E (90%) Melbourne nursing home residents, and 1473 (92%)
3E!#?N|v rural residents participated. In general, non-participants did
ed,w-;(n~ not differ from participants.16 The study population was
2 us-s representative of the Victorian population and Australia as
L=. 4x=%% a whole.
=ZsM[wd The Melbourne residents ranged in age from 40 to
m"2KAq61 98 years (mean = 59) and 1511 (46%) were male. The
k
\|[
= Melbourne nursing home residents ranged in age from 46 to
Z=ayVsJ3 101 years (mean = 82) and 85 (21%) were men. The rural
MI
|51&m residents ranged in age from 40 to 103 years (mean = 60)
/\%K7\ and 701 (47.5%) were men.
H$^b.5K Prevalence of cataract and prior cataract surgery
X(-e-:B4; As would be expected, the rate of any cataract increases
=:
+k dramatically with age (Table 1). The weighted rate of any
N0@&eX|$i4 cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
>H@
zP8 Although the rates varied somewhat between the three
wff&ci28 strata, they were not significantly different as the 95% confidence
k,L ,
limits overlapped. The per cent of cataractous eyes
\dyJ=tg with best-corrected visual acuity of less than 6/12 was 12.5%
{gE19J3 (65/520) for cortical cataract, 18% for nuclear cataract
kIAWI;H{ (97/534) and 14.4% (27/187) for PSC cataract. Cataract
+$MNG
surgery also rose dramatically with age. The overall
<a-I-~ weighted rate of prior cataract surgery in Victoria was
1cE3uA7 3.79% (95% CL 2.97, 4.60) (Table 2).
D6iHkDTg Risk factors for unoperated cataract
7$(>Z^ Em Cases of cataract that had not been removed were classified
kL.JrbM" as unoperated cataract. Risk factor analyses for unoperated
&qki
NS cataract were not performed with the nursing home residents
|
x|#n as information about risk factor exposure was not
'`q&UPg] available for this cohort. The following factors were assessed
K/Q^8%Z in relation to unoperated cataract: age, sex, residence
PaF`dnJ (urban/rural), language spoken at home (a measure of ethnic
n'D1s:W^B integration), country of birth, parents’ country of birth (a
bk E4{P" measure of ethnicity), years since migration, education, use
7Op6>i
of ophthalmic services, use of optometric services, private
X>w(^L*> health insurance status, duration of distance glasses use,
+tL]qOBP glaucoma, age-related maculopathy and employment status.
OWs K>egD In this cross sectional study it was not possible to assess the
2f1WT g) level of visual acuity that would predict a patient’s having
xzg81sV7 cataract surgery, as visual acuity data prior to cataract
1 dT1DcZ surgery were not available.
WjxOM\?# The significant risk factors for unoperated cataract in univariate
+0mU) 4n/ analyses were related to: whether a participant had
>HatbbA ever seen an optometrist, seen an ophthalmologist or been
@b\/\\{ diagnosed with glaucoma; and participants’ employment
V6Kw71'9 status (currently employed) and age. These significant
EnXNTat}) factors were placed in a backwards stepwise logistic regression
K1 M s model. The factors that remained significantly related
OosxuAC( to unoperated cataract were whether participants had ever
1.YDIB|| seen an ophthalmologist, seen an optometrist and been
@K; 4'b~ diagnosed with glaucoma. None of the demographic factors
tgy*!B6a~ were associated with unoperated cataract in the multivariate
8%]o6'd4 model.
iJE
$3 The per cent of participants with unoperated cataract
]6NpHDip1 who said that they were dissatisfied or very dissatisfied with
K^j7T[pR Operated and unoperated cataract in Australia 79
'+LbFGrO3 Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
d 6 t#4! Age group Sex Urban Rural Nursing home Weighted total
m,KG}KX (years) (%) (%) (%)
VWqmqR% 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
Jhdo#}Ub Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
5[3vup? 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
lt\.
)Y>4 Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
Os--@5e 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
?S^ U-.` Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
"J|{'k` 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
%O]]La
Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
(/TYET_H 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
3Au3>q, Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
RV^
N4q4 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
#[$^M:X. Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
6v(?Lr`D Age-standardized
SVKjhZK (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)
4#?Sxs aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
s6=jHrdvv their current vision was 30% (290/683), compared with 27%
4mYJ i#e6x (26/95) of participants with prior cataract surgery (chisquared,
Msj(>U&}+ 1 d.f. = 0.25, P = 0.62).
)Iu0MN& Outcomes of cataract surgery
kucH=96 Two hundred and forty-nine eyes had undergone prior
+9EG6"..@H cataract surgery. Of these 249 operated eyes, 49 (20%) were
S9\_ODv left aphakic, 6 (2.4%) had anterior chamber intraocular
'Lm\ r+$F lenses and 194 (78%) had posterior chamber intraocular
PydU.,^7 lenses. The rate of capsulotomy in the eyes with intact
u*n%cXY;J/ posterior capsules was 36% (73/202). Fifteen per cent of
Q8d-yJs& eyes (17/114) with a clear posterior capsule had bestcorrected
E~]37!,\\9 visual acuity of less than 6/12 compared with 43%
f%#q}vK- of eyes (6/14) with opaque capsules, and 15% of eyes
2Kg-ZDK8 (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
o'Rr2,lVi P = 0.027).
Ht`kmk;I) The percentage of eyes with best-corrected visual acuity
r@WfZZ of 6/12 or better was 96% (302/314) for eyes without
I(rZ(|^A cataract, 88% (1417/1609) for eyes with prevalent cataract
8&q[jxI@8 and 85% (211/249) for eyes with operated cataract (chisquared,
Uw!N;QsC 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
YB`
1S operated eyes (11%) had visual acuities of less than 6/18
_|^cudRv (moderate vision impairment) (Fig. 2). A cause of this
OV>JmYe1{/ moderate visual impairment (but not the only cause) in four
J?y0RX (15%) eyes was secondary to cataract surgery. Three of these
I9VU,8~ four eyes had undergone intracapsular cataract extraction
m7$t$/g and the fourth eye had an opaque posterior capsule. No one
Ea<kc[Q had bilateral vision impairment as a result of their cataract
'lWgHmE surgery.
$R&K-;D/8 DISCUSSION
;ElwF&"!X To our knowledge, this is the first paper to systematically
#_pQS}$ assess the prevalence of current cataract, previous cataract
k]"DsN$ surgery, predictors of unoperated cataract and the outcomes
fVvB8[(;~ of cataract surgery in a population-based sample. The Visual
T8t_+|(
G Impairment Project is unique in that the sampling frame and
P9
yg high response rate have ensured that the study population is
=zsA@UM0 representative of Australians aged 40 years and over. Therefore,
-]~KQvIH! these data can be used to plan age-related cataract
-\I".8"YE services throughout Australia.
;
8B)J<y We found the rate of any cataract in those over the age
~ TfN*0 of 40 years to be 22%. Although relatively high, this rate is
EvGKcu significantly less than was reported in a number of previous
Y'U]!c9 studies,2,4,6 with the exception of the Casteldaccia Eye
+@mgb4_ Study.5 However, it is difficult to compare rates of cataract
x%J.$o[<_ between studies because of different methodologies and
BenUyv1d cataract definitions employed in the various studies, as well
^&!iq K2o as the different age structures of the study populations.
q/eo
d Other studies have used less conservative definitions of
c`s ]ciC cataract, thus leading to higher rates of cataract as defined.
/oC@:7 In most large epidemiologic studies of cataract, visual acuity
njGZ#{"eC has not been included in the definition of cataract.
79d<,q;uR Therefore, the prevalence of cataract may not reflect the
E oh{+>:6 actual need for cataract surgery in the community.
iPK:gK3Q 80 McCarty et al.
b{(= C
3 Table 2. Prevalence of previous cataract by age, gender and cohort
,7os3~Mk9 Age group Gender Urban Rural Nursing home Weighted total
|_u|Td(n (years) (%) (%) (%)
Jq8:33s 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
<d
~IdK'\x Female 0.00 0.00 0.00 0.00 (
b~Un=-@5a 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
['_W< Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
(Y~gItej 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
w\%AR1,rs Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
fD~f_Wr 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
a"
!r]=r Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
z+{Q(8'b] 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
%
ou@Y` Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
%mNd9 ]< 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
n0vhc; d Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
fK10{>E1 Age-standardized
@,; VMO (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)
6g 5Lf) yG Figure 2. Visual acuity in eyes that had undergone cataract
&H:2TL! surgery, n = 249. h, Presenting; j, best-corrected.
v
O@7o
Operated and unoperated cataract in Australia 81
qrkJ:
The weighted prevalence of prior cataract surgery in the
UUR` m Visual Impairment Project (3.6%) was similar to the crude
bq"dKN` rate in the Beaver Dam Eye Study4 (3.1%), but less than the
LLd5Z44v crude rate in the Blue Mountains Eye Study6 (6.0%).
H{ +[
,l However, the age-standardized rate in the Blue Mountains
@
!,W]?{ Eye Study (standardized to the age distribution of the urban
jPmp=qg"q Visual Impairment Project cohort) was found to be less than
*x@.$=NF" the Visual Impairment Project (standardized rate = 1.36%,
c+.?
+g 95% CL 1.25, 1.47). The incidence of cataract surgery in
Q)93+1] Australia has exceeded population growth.1 This is due,
JqP~2,T perhaps, to advances in surgical techniques and lens
{ v#wU implants that have changed the risk–benefit ratio.
18AlQ+')?w The Global Initiative for the Elimination of Avoidable
N6w!V]b Blindness, sponsored by the World Health Organization,
}q=uI` states that cataract surgical services should be provided that
RFT`r ‘have a high success rate in terms of visual outcome and
+J
<<me4 improved quality of life’,17 although the ‘high success rate’ is
MOIMW+n not defined. Population- and clinic-based studies conducted
8w9?n3z=} in the United States have demonstrated marked improvement
^9
Pae) in visual acuity following cataract surgery.18–20 We
/
(?,S{] found that 85% of eyes that had undergone cataract extraction
^ SW!S_&Z2 had visual acuity of 6/12 or better. Previously, we have
a"whg~ shown that participants with prevalent cataract in this
\!s0H_RJY cohort are more likely to express dissatisfaction with their
OJXK]dZ current vision than participants without cataract or participants
9
M!U@> with prior cataract surgery.21 In a national study in the
SoNT12> United States, researchers found that the change in patients’
5v5K}hx ratings of their vision difficulties and satisfaction with their
C0[Z>$ vision after cataract surgery were more highly related to
6
u}c543 their change in visual functioning score than to their change
7|^5E*8/ in visual acuity.19 Furthermore, improvement in visual function
6i'kc3w has been shown to be associated with improvement in
N\W4LO6 overall quality of life.22
f ]DO2r A recent review found that the incidence of visually
Nj$h/P significant posterior capsule opacification following
0)E`6s#M cataract surgery to be greater than 25%.23 We found 36%
k8O%gO capsulotomy in our population and that this was associated
Ct0YwIR* with visual acuity similar to that of eyes with a clear
.;jp
2^ capsule, but significantly better than that of eyes with an
#ByrX\ opaque capsule.
GCv*a[8?n A number of studies have shown that the demand and
r>;6>ZMe timing of cataract surgery vary according to visual acuity,
BiCC72oig degree of handicap and socioeconomic factors.8–10,24,25 We
JQk][3Rv have also shown previously that ophthalmologists are more
N^xk.O_TO likely to refer a patient for cataract surgery if the patient is
'1[Bbs employed and less likely to refer a nursing home resident.7
m5\/7 VC In the Visual Impairment Project, we did not find that any
/I@Dv? particular subgroup of the population was at greater risk of
Mi2lBEu, having unoperated cataract. Universal access to health care
&#DKB#.2 in Australia may explain the fact that people without
aOK,Mm:iO Medicare are more likely to delay cataract operations in the
0VwmV_6'<W USA,8 but not having private health insurance is not associated
v+qHH8 with unoperated cataract in Australia.
bZ_vb? n In summary, cataract is a significant public health problem
z57|9$h}w in that one in four people in their 80s will have had cataract
&HIG776 surgery. The importance of age-related cataract surgery will
J6W
"t increase further with the ageing of the population: the
GjGt'
m* number of people over age 60 years is expected to double in
i.Jk(%c
the next 20 years. Cataract surgery services are well
9&7$oI$!J accessed by the Victorian population and the visual outcomes
OF/DI)j3 of cataract surgery have been shown to be very good.
QZ^P2==x These data can be used to plan for age-related cataract
VT~jgsY surgical services in Australia in the future as the need for
:bBMy\(u cataract extractions increases.
sV5S>*A[ ACKNOWLEDGEMENTS
HDV
$y=oHh The Visual Impairment Project was funded in part by grants
1KWGQJ%%s from the Victorian Health Promotion Foundation, the
G$_=rHt_% National Health and Medical Research Council, the Ansell
A57e]2_ Ophthalmology Foundation, the Dorothy Edols Estate and
)Ao
F-&,w the Jack Brockhoff Foundation. Dr McCarty is the recipient
?PSVVUq,Z of a Wagstaff Fellowship in Ophthalmology from the Royal
$(JB"%S8c Victorian Eye and Ear Hospital.
t!JD]j>q REFERENCES
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