ABSTRACT
{[[j .) Purpose: To quantify the prevalence of cataract, the outcomes
r;"uk+{i of cataract surgery and the factors related to
JA]qAr unoperated cataract in Australia.
,UA-Pq3} Methods: Participants were recruited from the Visual
?AlTQL~c Impairment Project: a cluster, stratified sample of more than
SmMJ%lgA6 5000 Victorians aged 40 years and over. At examination
D&]dlY@* sites interviews, clinical examinations and lens photography
YsBOh{Ml were performed. Cataract was defined in participants who
wc~k4B9" had: had previous cataract surgery, cortical cataract greater
*B0
7- than 4/16, nuclear greater than Wilmer standard 2, or
vUD>+*D posterior subcapsular greater than 1 mm2.
0XLoGQ
= Results: The participant group comprised 3271 Melbourne
NNTUl$ residents, 403 Melbourne nursing home residents and 1473
h;RKF\U:" rural residents.The weighted rate of any cataract in Victoria
VYAz0H1-_ was 21.5%. The overall weighted rate of prior cataract
-6yFE- X/ surgery was 3.79%. Two hundred and forty-nine eyes had
rd0[(- had prior cataract surgery. Of these 249 procedures, 49
eI:;l];G9 (20%) were aphakic, 6 (2.4%) had anterior chamber
l6y*SW5+ intraocular lenses and 194 (78%) had posterior chamber
wx*)7Y* intraocular lenses.Two hundred and eleven of these operated
tEC`->| eyes (85%) had best-corrected visual acuity of 6/12 or
\|< 5zL better, the legal requirement for a driver’s license.Twentyseven
<`Q*I
Y (11%) had visual acuity of less than 6/18 (moderate
jv5Os- vision impairment). Complications of cataract surgery
A{(<#yRfg caused reduced vision in four of the 27 eyes (15%), or 1.9%
laX67Vjv of operated eyes. Three of these four eyes had undergone
|.;LI=CT intracapsular cataract extraction and the fourth eye had an
?T\_"G opaque posterior capsule. No one had bilateral vision
MET"s.v impairment as a result of cataract surgery. Surprisingly, no
#->#mshd4 particular demographic factors (such as age, gender, rural
NUjo5.7 residence, occupation, employment status, health insurance
`
xm4?6 status, ethnicity) were related to the presence of unoperated
/'WIgP cataract.
\}9GK`oR Conclusions: Although the overall prevalence of cataract is
O9Fg_qfuT_ quite high, no particular subgroup is systematically underserviced
.C7;T'>! in terms of cataract surgery. Overall, the results of
C?h`i ^ >2 cataract surgery are very good, with the majority of eyes
VsTa!V^~ achieving driving vision following cataract extraction.
yG%<LP2p@f Key words: cataract extraction, health planning, health
Rb=8(# services accessibility, prevalence
dXvp-oi INTRODUCTION
SeX:A)*ez% Cataract is the leading cause of blindness worldwide and, in
tM&;b?bJ[ Australia, cataract extractions account for the majority of all
tMQz'3,X ophthalmic procedures.1 Over the period 1985–94, the rate
\Tii
S of cataract surgery in Australia was twice as high as would be
Xj+oV expected from the growth in the elderly population.1
RLtIn!2OU Although there have been a number of studies reporting
TP-<Lhy the prevalence of cataract in various populations,2–6 there is
]Y%U5\$ little information about determinants of cataract surgery in
MlBw=Nr the population. A previous survey of Australian ophthalmologists
7vf?#^RlV showed that patient concern and lifestyle, rather
3jG
#<4;J than visual acuity itself, are the primary factors for referral
*[MK
{m for cataract surgery.7 This supports prior research which has
])YGeY(V0+ shown that visual acuity is not a strong predictor of need for
|>2IgTh1a cataract surgery.8,9 Elsewhere, socioeconomic status has
-Ze{d
$ been shown to be related to cataract surgery rates.10
z%pD3J?> To appropriately plan health care services, information is
}Cy
S_Tc needed about the prevalence of age-related cataract in the
:1O1I2L0 community as well as the factors associated with cataract
{g7[3WRy surgery. The purpose of this study is to quantify the prevalence
h)746T ) of any cataract in Australia, to describe the factors
|8s)kQ4$ related to unoperated cataract in the community and to
cx(W{O"Jb describe the visual outcomes of cataract surgery.
;C+g)BW METHODS
~il{6Z+#n Study population
ydyGPZt Details about the study methodology for the Visual
i47xF7y\ Impairment Project have been published previously.11
Qf}^x9' Briefly, cluster sampling within three strata was employed to
?<#2raH- recruit subjects aged 40 years and over to participate.
ZSu0e% Within the Melbourne Statistical Division, nine pairs of
u?>]C6$ census collector districts were randomly selected. Fourteen
<R?_Yjs
w nursing homes within a 5 km radius of these nine test sites
j
r9/ were randomly chosen to recruit nursing home residents.
bxS+ R\ Clinical and Experimental Ophthalmology (2000) 28, 77–82
D<m+M@u Original Article
N{f4-i~ Operated and unoperated cataract in Australia
_IK@K6V1 Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
mu1Lg s$; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
&!kr&g#] n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
( _{\tgSm Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au o~*5FN}%+l 78 McCarty et al.
'<v/Gl\ Finally, four pairs of census collector districts in four rural
73C
Victorian communities were randomly selected to recruit rural
Dw@0P residents. A household census was conducted to identify
Q6?}/p eligible residents aged 40 years and over who had been a
?Q< o-o;B resident at that address for at least 6 months. At the time of
"z^&>#F the household census, basic information about age, sex,
\y-Lt!} country of birth, language spoken at home, education, use of
u,d@oF(= corrective spectacles and use of eye care services was collected.
<V3N!H_d Eligible residents were then invited to attend a local
@CSTp6{y examination site for a more detailed interview and examination.
ZjE!?
'(ef The study protocol was approved by the Royal Victorian
amL8yb Eye and Ear Hospital Human Research Ethics Committee.
DO!?]" Assessment of cataract
]Y3|*t(\ A standardized ophthalmic examination was performed after
3zO'=gwJ pupil dilatation with one drop of 10% phenylephrine
+M+ht
hydrochloride. Lens opacities were graded clinically at the
w/KCuW< time of the examination and subsequently from photos using
ccW z,[ the Wilmer cataract photo-grading system.12 Cortical and
}Om+,!_d posterior subcapsular (PSC) opacities were assessed on
HS|X//] retroillumination and measured as the proportion (in 1/16)
:eK;:pN of pupil circumference occupied by opacity. For this analysis,
L`yyn/2> cortical cataract was defined as 4/16 or greater opacity,
|]5g+sd PSC cataract was defined as opacity equal to or greater than
R~,*W1G6sF 1 mm2 and nuclear cataract was defined as opacity equal to
C(:tFuacpw or greater than Wilmer standard 2,12 independent of visual
v'C`;I acuity. Examples of the minimum opacities defined as cortical,
Z#wmEc.}C nuclear and PSC cataract are presented in Figure 1.
$I L7c]Gw Bilateral congenital cataracts or cataracts secondary to
D?u*^?
a2 intraocular inflammation or trauma were excluded from the
cS98%@DR analysis. Two cases of bilateral secondary cataract and eight
(;o,t?:d cases of bilateral congenital cataract were excluded from the
!b"#`O%` analyses.
':71;^zXf A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
C:n55BE9 Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
*`:zSnu height set to an incident angle of 30° was used for examinations.
eKlh }v Ektachrome® 200 ASA colour slide film (Eastman
`Jh> 1l Kodak Company, Rochester, NY, USA) was used to photograph
$cri"G the nuclear opacities. The cortical opacities were
%C%~f{4 photographed with an Oxford® retroillumination camera
FO{K=9O (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
NTk"W!<Cl2 film (Eastman Kodak). Photographs were graded separately
$
X~4J by two research assistants and discrepancies were adjudicated
DfFsCTu by an independent reviewer. Any discrepancies
-I.OvzQ* between the clinical grades and the photograph grades were
5taYm' resolved. Except in cases where photographs were missing,
>3
Q%Yn the photograph grades were used in the analyses. Photograph
J7BfH,o grades were available for 4301 (84%) for cortical
u>j:8lhtV cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
:]Jwcp for PSC cataract. Cataract status was classified according to
NAjK0]SRY the severity of the opacity in the worse eye.
]3<k>? Assessment of risk factors
|1H"ya A standardized questionnaire was used to obtain information
-Cwx % about education, employment and ethnic background.11
'{j.5~4y Specific information was elicited on the occurrence, duration
fr8:L!9 and treatment of a number of medical conditions,
8Letpygm including ocular trauma, arthritis, diabetes, gout, hypertension
;2
oR?COW and mental illness. Information about the use, dose and
P?dE\Po7 duration of tobacco, alcohol, analgesics and steriods were
_"%ef"oPh collected, and a food frequency questionnaire was used to
WC,&p determine current consumption of dietary sources of antioxidants
f{[U->#^ and use of vitamin supplements.
EUj'%;sz- Data management and statistical analysis
PZ~uHX_d> Data were collected either by direct computer entry with a
2-i>ymoOS questionnaire programmed in Paradox© (Carel Corporation,
uYAPGs#k Ottawa, Canada) with internal consistency checks, or
Y9ueE+6 on self-coding forms. Open-ended responses were coded at
ZKyK#\v< a later time. Data that were entered on the self-coded forms
PA;RUe
were entered into a computer with double data entry and
>(Jy=m? reconciliation of any inconsistencies. Data range and consistency
S`TP#uzKu] checks were performed on the entire data set.
CZv.$H"lW SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
J')Dt]/9 employed for statistical analyses.
Wq8Uq}~_g Ninety-five per cent confidence limits around the agespecific
LX[J6YKR rates were calculated according to Cochran13 to
PhF3'
"> account for the effect of the cluster sampling. Ninety-five
.?9+1.` per cent confidence limits around age-standardized rates
"0Uh(9Fv were calculated according to Breslow and Day.14 The strataspecific
)Ac+5bs data were weighted according to the 1996
*xXa4HB Australian Bureau of Statistics census data15 to reflect the
g
PogV(V cataract prevalence in the entire Victorian population.
o0^'xVv Univariate analyses with Student’s t-tests and chi-squared
{4Cn/}7Ly^ tests were first employed to evaluate risk factors for unoperated
:)X?ML? cataract. Any factors with P < 0.10 were then fitted
LF?83P,UJ# into a backwards stepwise logistic regression model. For the
>up'`K, Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
C"_f3[Z final multivariate models, P < 0.05 was considered statistically
X64OX9:YF significant. Design effect was assessed through the use
W+V#z8K of cluster-specific models and multivariate models. The
c%w@-n` design effect was assumed to be additive and an adjustment
'm9f:iTr made in the variance by adding the variance associated with
*IUw$|Z6z) the design effect prior to constructing the 95% confidence
|ZW%+AQ|
limits.
a@Tn_y
X RESULTS
iX qB-4" Study population
!xyO A total of 3271 (83%) of the Melbourne residents, 403
3Vj
uk7 (90%) Melbourne nursing home residents, and 1473 (92%)
I
<`9ANe rural residents participated. In general, non-participants did
4thLK8/c5g not differ from participants.16 The study population was
?#idmb}( representative of the Victorian population and Australia as
#k5WTcE a whole.
L{(\k$>' The Melbourne residents ranged in age from 40 to
Z<6xQTx 98 years (mean = 59) and 1511 (46%) were male. The
b}4k-hZL Melbourne nursing home residents ranged in age from 46 to
3>q
UYxG8 101 years (mean = 82) and 85 (21%) were men. The rural
I`w1IIY?m residents ranged in age from 40 to 103 years (mean = 60)
de]r
9$D and 701 (47.5%) were men.
ZeD; Prevalence of cataract and prior cataract surgery
@sv==|h As would be expected, the rate of any cataract increases
ei
'=%r8~ dramatically with age (Table 1). The weighted rate of any
0 (jb19 cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
n~N>c*p Although the rates varied somewhat between the three
*f|9A/*B3 strata, they were not significantly different as the 95% confidence
k .?
aq limits overlapped. The per cent of cataractous eyes
4} uX[~e& with best-corrected visual acuity of less than 6/12 was 12.5%
Y,K): ~T (65/520) for cortical cataract, 18% for nuclear cataract
.CH0PK=l (97/534) and 14.4% (27/187) for PSC cataract. Cataract
&RP!9{F< surgery also rose dramatically with age. The overall
xMJF1O?3 weighted rate of prior cataract surgery in Victoria was
B$qmXA)ze 3.79% (95% CL 2.97, 4.60) (Table 2).
{n
}6 Risk factors for unoperated cataract
c7T9kV8hS Cases of cataract that had not been removed were classified
+F q`I2l| as unoperated cataract. Risk factor analyses for unoperated
MN\/F4Io cataract were not performed with the nursing home residents
Q#xeu as information about risk factor exposure was not
|eL&hwqzG available for this cohort. The following factors were assessed
:Z(?Ct&8 in relation to unoperated cataract: age, sex, residence
3nv7Uz
(urban/rural), language spoken at home (a measure of ethnic
)\_xB_K\ integration), country of birth, parents’ country of birth (a
KpBh@S measure of ethnicity), years since migration, education, use
n's3!HQY[ of ophthalmic services, use of optometric services, private
2%\Nq:;T health insurance status, duration of distance glasses use,
m)9N9Ii#) glaucoma, age-related maculopathy and employment status.
'Y3>+7bI In this cross sectional study it was not possible to assess the
3n9$qr=' level of visual acuity that would predict a patient’s having
NhQIpzL) cataract surgery, as visual acuity data prior to cataract
mLX1w)=r surgery were not available.
,}F2l|x_ The significant risk factors for unoperated cataract in univariate
=BJ/ZM analyses were related to: whether a participant had
2pFOC;tl ever seen an optometrist, seen an ophthalmologist or been
?TLEZlB2" diagnosed with glaucoma; and participants’ employment
cAC2Xq status (currently employed) and age. These significant
NWPL18*C factors were placed in a backwards stepwise logistic regression
, M$*c model. The factors that remained significantly related
Mp;t?C4 to unoperated cataract were whether participants had ever
$+Ke$fq.> seen an ophthalmologist, seen an optometrist and been
g(<02t!OT= diagnosed with glaucoma. None of the demographic factors
9x.vz were associated with unoperated cataract in the multivariate
I2("p.+R model.
qT#+DDEAL The per cent of participants with unoperated cataract
]3hz{zqV^ who said that they were dissatisfied or very dissatisfied with
>bxT_qEm Operated and unoperated cataract in Australia 79
Ou/@!Y1 Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
ZmO/6_nU? Age group Sex Urban Rural Nursing home Weighted total
udB:ys (years) (%) (%) (%)
*{tn/ro6a 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
R?+Eo(0q, Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
kac@yQD 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
,HS\
(Z Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
|DfYH~@( 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
`m<l8'g Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
{@g3AG% 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
VY<v?Of
i- Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
m}6GVQ'Q 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
}aXc,;Ps Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
_Pa(5-S'KR 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
!Qrlb>1z- Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
VZYdCZ&l7 Age-standardized
jD0^,aiG (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)
'1ff| c!x9 aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
kxoJL6IC their current vision was 30% (290/683), compared with 27%
gm8L
5c
V (26/95) of participants with prior cataract surgery (chisquared,
X55Eemg/ 1 d.f. = 0.25, P = 0.62).
:<gmgI Outcomes of cataract surgery
n5 @H Two hundred and forty-nine eyes had undergone prior
Zi$a6 cataract surgery. Of these 249 operated eyes, 49 (20%) were
Ia)wlA02S left aphakic, 6 (2.4%) had anterior chamber intraocular
G9 z Q{E lenses and 194 (78%) had posterior chamber intraocular
=r+u!~%@'' lenses. The rate of capsulotomy in the eyes with intact
W2tIt&{ posterior capsules was 36% (73/202). Fifteen per cent of
"vH@b_>9| eyes (17/114) with a clear posterior capsule had bestcorrected
v;el= D visual acuity of less than 6/12 compared with 43%
P^v`5v of eyes (6/14) with opaque capsules, and 15% of eyes
Ee9u
7TFT (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
&AGV0{NMh] P = 0.027).
8_U*_I7( The percentage of eyes with best-corrected visual acuity
x_v pds of 6/12 or better was 96% (302/314) for eyes without
q ]rsp0P2 cataract, 88% (1417/1609) for eyes with prevalent cataract
{#=q[jVi%1 and 85% (211/249) for eyes with operated cataract (chisquared,
|=l;UqB 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
Y!i4P#4+q operated eyes (11%) had visual acuities of less than 6/18
PAH;
+ (moderate vision impairment) (Fig. 2). A cause of this
|6`yE]3-( moderate visual impairment (but not the only cause) in four
azPFKg+ (15%) eyes was secondary to cataract surgery. Three of these
@`$8rck` four eyes had undergone intracapsular cataract extraction
~8`r.1aUO and the fourth eye had an opaque posterior capsule. No one
$4 >K2 had bilateral vision impairment as a result of their cataract
ED[PP2[/ surgery.
LEc%BQx
DISCUSSION
#p*{p)]HiA To our knowledge, this is the first paper to systematically
ocAoq
jlT[ assess the prevalence of current cataract, previous cataract
a[xEN7L~4D surgery, predictors of unoperated cataract and the outcomes
CO0Nq/@ of cataract surgery in a population-based sample. The Visual
a5?Rj~h!< Impairment Project is unique in that the sampling frame and
vov"60K high response rate have ensured that the study population is
7tUl$H;I/R representative of Australians aged 40 years and over. Therefore,
)+N%!(ki these data can be used to plan age-related cataract
f`RcfYt services throughout Australia.
/AjGj*O We found the rate of any cataract in those over the age
Z99%uI3 of 40 years to be 22%. Although relatively high, this rate is
!R[o6V5T significantly less than was reported in a number of previous
v#(wc+[ studies,2,4,6 with the exception of the Casteldaccia Eye
bxc#bl3 Study.5 However, it is difficult to compare rates of cataract
$a(wM1S4 between studies because of different methodologies and
?%iAkV cataract definitions employed in the various studies, as well
wP+wA}SN
as the different age structures of the study populations.
U:#9!J?41 Other studies have used less conservative definitions of
,N<xyx. cataract, thus leading to higher rates of cataract as defined.
*
"~^k^_b} In most large epidemiologic studies of cataract, visual acuity
z./u;/: has not been included in the definition of cataract.
o D*h@yL Therefore, the prevalence of cataract may not reflect the
0KHA5dt actual need for cataract surgery in the community.
&f|LjpMCf 80 McCarty et al.
UKZsq5Q Table 2. Prevalence of previous cataract by age, gender and cohort
ZxwI< T:& Age group Gender Urban Rural Nursing home Weighted total
w6qx (years) (%) (%) (%)
,+oQ
5c(f 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
hof:36 < Female 0.00 0.00 0.00 0.00 (
>(|T]u](q 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
\.POb5]p0 Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
y7u"a)T 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
KaauX
m Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
V[(zRGa{ 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
dK#:io[Nz Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
h&{9 &D1t 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
l7Zqk GG] Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
(ye1t96 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
-L NJ*?b Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
G yvEc3|@ Age-standardized
XPBKQm_} (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)
>KNiMW^V Figure 2. Visual acuity in eyes that had undergone cataract
[O2xE037h` surgery, n = 249. h, Presenting; j, best-corrected.
}G]6Rip3 Operated and unoperated cataract in Australia 81
$>hPB[ [ The weighted prevalence of prior cataract surgery in the
%|*tL7 Visual Impairment Project (3.6%) was similar to the crude
u3a"[DB9c rate in the Beaver Dam Eye Study4 (3.1%), but less than the
': 87.8$ crude rate in the Blue Mountains Eye Study6 (6.0%).
8doKB<#_+= However, the age-standardized rate in the Blue Mountains
%c<e`P; Eye Study (standardized to the age distribution of the urban
,6=j'j1#a Visual Impairment Project cohort) was found to be less than
2-s ,PQno^ the Visual Impairment Project (standardized rate = 1.36%,
i+
]3J/J 95% CL 1.25, 1.47). The incidence of cataract surgery in
-y|>#`T/ Australia has exceeded population growth.1 This is due,
v-B{7
~=#Z perhaps, to advances in surgical techniques and lens
$M5iU@A implants that have changed the risk–benefit ratio.
J$F
1sy The Global Initiative for the Elimination of Avoidable
_ I"}3* Blindness, sponsored by the World Health Organization,
3k(A&]~v states that cataract surgical services should be provided that
Q'5]E{1<'n ‘have a high success rate in terms of visual outcome and
wW
EnA
W~ improved quality of life’,17 although the ‘high success rate’ is
"
R!,5HQF; not defined. Population- and clinic-based studies conducted
F$.h+v in the United States have demonstrated marked improvement
|(u6xPs;P in visual acuity following cataract surgery.18–20 We
s;e%*4 found that 85% of eyes that had undergone cataract extraction
JN)@bP had visual acuity of 6/12 or better. Previously, we have
bWWZGl
9 shown that participants with prevalent cataract in this
;
l`
us cohort are more likely to express dissatisfaction with their
]dIcW9a current vision than participants without cataract or participants
ywQ[>itMa with prior cataract surgery.21 In a national study in the
2>TOCBB" United States, researchers found that the change in patients’
'tvX.aX2 ratings of their vision difficulties and satisfaction with their
xKl\:}Ytp vision after cataract surgery were more highly related to
4FQB%3>* their change in visual functioning score than to their change
'^B[Krs'Z` in visual acuity.19 Furthermore, improvement in visual function
.JCd:'- has been shown to be associated with improvement in
+*uaB overall quality of life.22
\.ukZqB3
0 A recent review found that the incidence of visually
4N6JKS significant posterior capsule opacification following
4}4 cA\B:n cataract surgery to be greater than 25%.23 We found 36%
DpQ\q; capsulotomy in our population and that this was associated
OFe-e(c1 with visual acuity similar to that of eyes with a clear
=$mPReA3v capsule, but significantly better than that of eyes with an
W{Uz#o
opaque capsule.
QNbV=*F? A number of studies have shown that the demand and
6mV-+CnYC timing of cataract surgery vary according to visual acuity,
}fO+b5U degree of handicap and socioeconomic factors.8–10,24,25 We
Upw`|$1S have also shown previously that ophthalmologists are more
)DB\du likely to refer a patient for cataract surgery if the patient is
Zzn
N"Si, employed and less likely to refer a nursing home resident.7
8;Zz25* In the Visual Impairment Project, we did not find that any
] M`%@ps particular subgroup of the population was at greater risk of
3 C{A having unoperated cataract. Universal access to health care
U7#C. Z in Australia may explain the fact that people without
}#r awVe= Medicare are more likely to delay cataract operations in the
k,eo+qH.Hz USA,8 but not having private health insurance is not associated
|
|"W=E with unoperated cataract in Australia.
"7q!u,u In summary, cataract is a significant public health problem
ui
RO,B}z in that one in four people in their 80s will have had cataract
(^oN, 7 surgery. The importance of age-related cataract surgery will
k?Kt*T increase further with the ageing of the population: the
_?>x{![ number of people over age 60 years is expected to double in
j"hNkCF the next 20 years. Cataract surgery services are well
|yl,7m/B-G accessed by the Victorian population and the visual outcomes
=MU(!` of cataract surgery have been shown to be very good.
{p.^E5& These data can be used to plan for age-related cataract
!>\&*h-Cm# surgical services in Australia in the future as the need for
4VF4 8 cataract extractions increases.
e"y-A&| ACKNOWLEDGEMENTS
QJ&]4*>a The Visual Impairment Project was funded in part by grants
IaZmN.k* from the Victorian Health Promotion Foundation, the
V0NLwl
O National Health and Medical Research Council, the Ansell
5@DCo Ophthalmology Foundation, the Dorothy Edols Estate and
fMIRr5 the Jack Brockhoff Foundation. Dr McCarty is the recipient
<2d)4@B= of a Wagstaff Fellowship in Ophthalmology from the Royal
15
@2h Victorian Eye and Ear Hospital.
LC4VlfU
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