ABSTRACT
t =ErJ Purpose: To quantify the prevalence of cataract, the outcomes
k\UDZ)TQV of cataract surgery and the factors related to
)x1LOMe unoperated cataract in Australia.
$~xY6"_}!! Methods: Participants were recruited from the Visual
^lCys Impairment Project: a cluster, stratified sample of more than
#M;Cw}pW 5000 Victorians aged 40 years and over. At examination
<S'5`-& sites interviews, clinical examinations and lens photography
Fv \yhR were performed. Cataract was defined in participants who
U$R+&@; had: had previous cataract surgery, cortical cataract greater
UxZT&x3=)} than 4/16, nuclear greater than Wilmer standard 2, or
VU7x w posterior subcapsular greater than 1 mm2.
R9X*R3n
B Results: The participant group comprised 3271 Melbourne
^J3\
U{B residents, 403 Melbourne nursing home residents and 1473
"G\OKt'Z rural residents.The weighted rate of any cataract in Victoria
q.6$-w was 21.5%. The overall weighted rate of prior cataract
'ojI_%9< surgery was 3.79%. Two hundred and forty-nine eyes had
(;2J}XQvO~ had prior cataract surgery. Of these 249 procedures, 49
LyM" (20%) were aphakic, 6 (2.4%) had anterior chamber
Ky33h 0TX intraocular lenses and 194 (78%) had posterior chamber
,6Ulj+l intraocular lenses.Two hundred and eleven of these operated
Q70LQCms eyes (85%) had best-corrected visual acuity of 6/12 or
o*7`r ~ better, the legal requirement for a driver’s license.Twentyseven
1A;>@4iC0 (11%) had visual acuity of less than 6/18 (moderate
5tMp@$F\{[ vision impairment). Complications of cataract surgery
1*aw~nY0 caused reduced vision in four of the 27 eyes (15%), or 1.9%
2
F3U,} of operated eyes. Three of these four eyes had undergone
s u]x intracapsular cataract extraction and the fourth eye had an
cx?t C#t opaque posterior capsule. No one had bilateral vision
zmk# gk2H impairment as a result of cataract surgery. Surprisingly, no
.du FMJl particular demographic factors (such as age, gender, rural
/7Z;/|
oU residence, occupation, employment status, health insurance
ZW\}4q;[A status, ethnicity) were related to the presence of unoperated
p`ai2`qC` cataract.
u!TVvc Conclusions: Although the overall prevalence of cataract is
SS;[{u! quite high, no particular subgroup is systematically underserviced
iXpLcHi in terms of cataract surgery. Overall, the results of
4%do.D* cataract surgery are very good, with the majority of eyes
!"{+|heU9p achieving driving vision following cataract extraction.
s,UccA@ Key words: cataract extraction, health planning, health
).HYW _Yih services accessibility, prevalence
V_*TY6 INTRODUCTION
bM`7>3
d7E Cataract is the leading cause of blindness worldwide and, in
g:bw;6^u Australia, cataract extractions account for the majority of all
-z%|
Jk ophthalmic procedures.1 Over the period 1985–94, the rate
qI,4uGg of cataract surgery in Australia was twice as high as would be
|/B2Bm expected from the growth in the elderly population.1
FL-yt Although there have been a number of studies reporting
VY }?Nb<& the prevalence of cataract in various populations,2–6 there is
=sVB.P little information about determinants of cataract surgery in
W~sP7&sp the population. A previous survey of Australian ophthalmologists
|1vikG8 showed that patient concern and lifestyle, rather
$7%e|0jC than visual acuity itself, are the primary factors for referral
F.:B_t for cataract surgery.7 This supports prior research which has
nY7
ZK shown that visual acuity is not a strong predictor of need for
r@;n \ cataract surgery.8,9 Elsewhere, socioeconomic status has
)L}6to been shown to be related to cataract surgery rates.10
&sJZSrk| To appropriately plan health care services, information is
Y>}[c
needed about the prevalence of age-related cataract in the
5x";}Vp>P community as well as the factors associated with cataract
P~Cx#`#(V surgery. The purpose of this study is to quantify the prevalence
.H,v7L,~88 of any cataract in Australia, to describe the factors
bnS"@^M related to unoperated cataract in the community and to
E:,V{&tLK describe the visual outcomes of cataract surgery.
8RS=Xemds METHODS
V@6,\1#`| Study population
0'ha!4h3Z Details about the study methodology for the Visual
"/v{B?~%! Impairment Project have been published previously.11
"P O>@tY Briefly, cluster sampling within three strata was employed to
dD _(MbTt recruit subjects aged 40 years and over to participate.
+
k1|+z
zS Within the Melbourne Statistical Division, nine pairs of
8 /3`rEW census collector districts were randomly selected. Fourteen
pJ*x[y nursing homes within a 5 km radius of these nine test sites
04eE\%? were randomly chosen to recruit nursing home residents.
$f`\TKlN Clinical and Experimental Ophthalmology (2000) 28, 77–82
o /uA_19 Original Article
3\J-=U Operated and unoperated cataract in Australia
pa1.+ ~) Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
ROZOX$XM Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
hdZ{8 rP n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
YcJZG|[ Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au 7]}n0*fe 78 McCarty et al.
4L'dV Finally, four pairs of census collector districts in four rural
Gt9(@USK Victorian communities were randomly selected to recruit rural
EjZ_|Q residents. A household census was conducted to identify
e
C\;n eligible residents aged 40 years and over who had been a
FbxrBM resident at that address for at least 6 months. At the time of
nW1Obu8x| the household census, basic information about age, sex,
6.X| .N country of birth, language spoken at home, education, use of
RLuA^ONI corrective spectacles and use of eye care services was collected.
!RX7TYf Eligible residents were then invited to attend a local
!L..I2' examination site for a more detailed interview and examination.
i9KQpWG: The study protocol was approved by the Royal Victorian
U/v }4b Eye and Ear Hospital Human Research Ethics Committee.
4.?tP7UE Assessment of cataract
zoFCHsr A standardized ophthalmic examination was performed after
:u}FF"j pupil dilatation with one drop of 10% phenylephrine
{(o$? = hydrochloride. Lens opacities were graded clinically at the
r*e<`Is time of the examination and subsequently from photos using
&O0@)jIV the Wilmer cataract photo-grading system.12 Cortical and
ZHQa}C+ posterior subcapsular (PSC) opacities were assessed on
nP9zTa retroillumination and measured as the proportion (in 1/16)
Yv="oG!xL of pupil circumference occupied by opacity. For this analysis,
BT?)-wS cortical cataract was defined as 4/16 or greater opacity,
sn.Xvk%75 PSC cataract was defined as opacity equal to or greater than
J|vriI; 1 mm2 and nuclear cataract was defined as opacity equal to
'q+CL&D or greater than Wilmer standard 2,12 independent of visual
r!DUsE acuity. Examples of the minimum opacities defined as cortical,
#0yU
K5J nuclear and PSC cataract are presented in Figure 1.
K,pQ11J Bilateral congenital cataracts or cataracts secondary to
Xi^#F;@sU intraocular inflammation or trauma were excluded from the
e!+_U C analysis. Two cases of bilateral secondary cataract and eight
_*(n2'
2B cases of bilateral congenital cataract were excluded from the
-Re4G78% analyses.
x>Hg.%/c[ A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
&y1
64xn'h Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
5.1 c#rL height set to an incident angle of 30° was used for examinations.
dd $}FlT Ektachrome® 200 ASA colour slide film (Eastman
Rd 4
z+G Kodak Company, Rochester, NY, USA) was used to photograph
y$JM=f$ the nuclear opacities. The cortical opacities were
e.8(t
EqZ1 photographed with an Oxford® retroillumination camera
-F&4<\=+ (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
ups]k?4 film (Eastman Kodak). Photographs were graded separately
zOV.cI6fZz by two research assistants and discrepancies were adjudicated
DOk(5gR by an independent reviewer. Any discrepancies
zjuU*$A4 between the clinical grades and the photograph grades were
^#^\@jLm resolved. Except in cases where photographs were missing,
5*Wo/%#q the photograph grades were used in the analyses. Photograph
G-vBJlt=t grades were available for 4301 (84%) for cortical
hcQky/c\#b cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
UK{6Rh
; for PSC cataract. Cataract status was classified according to
7'pmW,; the severity of the opacity in the worse eye.
a{oG[e Assessment of risk factors
:P!"'&gCL A standardized questionnaire was used to obtain information
`i'72\( about education, employment and ethnic background.11
3hN.`G-E Specific information was elicited on the occurrence, duration
1WArgR and treatment of a number of medical conditions,
>?pWbL including ocular trauma, arthritis, diabetes, gout, hypertension
BtPUUy. and mental illness. Information about the use, dose and
{C% #r@6 duration of tobacco, alcohol, analgesics and steriods were
`7f><p/q collected, and a food frequency questionnaire was used to
dKKh ^D`~ determine current consumption of dietary sources of antioxidants
LF2@qv w D and use of vitamin supplements.
`|{6U"n Data management and statistical analysis
s>pOfXIx Data were collected either by direct computer entry with a
IvW%n(a8^ questionnaire programmed in Paradox© (Carel Corporation,
f3g
#(1 Ottawa, Canada) with internal consistency checks, or
R a> k
#pQ on self-coding forms. Open-ended responses were coded at
fmDn1N-bG a later time. Data that were entered on the self-coded forms
hkK+BmMj\ were entered into a computer with double data entry and
CY"iP,nHl reconciliation of any inconsistencies. Data range and consistency
5BztOYn, checks were performed on the entire data set.
?iX1;c9 SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
SO~]aFoYt employed for statistical analyses.
u:6PAVW? Ninety-five per cent confidence limits around the agespecific
5|4=uoA< rates were calculated according to Cochran13 to
0<,Q7onDD: account for the effect of the cluster sampling. Ninety-five
/Ir|& <yB per cent confidence limits around age-standardized rates
Ps0g were calculated according to Breslow and Day.14 The strataspecific
&~%(
RO data were weighted according to the 1996
L\:f#b~W Australian Bureau of Statistics census data15 to reflect the
fs43\m4=m cataract prevalence in the entire Victorian population.
%XpYiW#AK Univariate analyses with Student’s t-tests and chi-squared
wFgL\[$^| tests were first employed to evaluate risk factors for unoperated
wR x5`
@ cataract. Any factors with P < 0.10 were then fitted
FMuakCic5 into a backwards stepwise logistic regression model. For the
?|&plf| Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
/7bIE!Cn final multivariate models, P < 0.05 was considered statistically
L>,j*a_[ significant. Design effect was assessed through the use
P3due|4M of cluster-specific models and multivariate models. The
FY^#%0~ design effect was assumed to be additive and an adjustment
uSAb made in the variance by adding the variance associated with
6{XdLI the design effect prior to constructing the 95% confidence
HjX!a29Wf limits.
c|kQ3( RESULTS
V4('}Q! Study population
b),_rr A total of 3271 (83%) of the Melbourne residents, 403
Ww{|:>j (90%) Melbourne nursing home residents, and 1473 (92%)
2EHeQ|# rural residents participated. In general, non-participants did
:6^8Q,C1@ not differ from participants.16 The study population was
w|"cf{$^x representative of the Victorian population and Australia as
Kg#5
@; a whole.
Ji> The Melbourne residents ranged in age from 40 to
[n53eC 98 years (mean = 59) and 1511 (46%) were male. The
J!%cHqR Melbourne nursing home residents ranged in age from 46 to
\Ty%E< 101 years (mean = 82) and 85 (21%) were men. The rural
*-!&5~o/U residents ranged in age from 40 to 103 years (mean = 60)
,W'?F9Y\ and 701 (47.5%) were men.
uq}>5 Prevalence of cataract and prior cataract surgery
[5v[
Zqud As would be expected, the rate of any cataract increases
[@Db7]nG dramatically with age (Table 1). The weighted rate of any
>3S^9{d cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
%-Z0OzWe Although the rates varied somewhat between the three
IZ2c<B5& strata, they were not significantly different as the 95% confidence
x?ajTzMv limits overlapped. The per cent of cataractous eyes
nDR)UR with best-corrected visual acuity of less than 6/12 was 12.5%
qR
WWG& (65/520) for cortical cataract, 18% for nuclear cataract
S?Y,sl+A: (97/534) and 14.4% (27/187) for PSC cataract. Cataract
N6GvzmG#g surgery also rose dramatically with age. The overall
zU+` o?al weighted rate of prior cataract surgery in Victoria was
9s5PJj "u 3.79% (95% CL 2.97, 4.60) (Table 2).
DqLZc01> Risk factors for unoperated cataract
x<
Td Cases of cataract that had not been removed were classified
0G(T'Z1 as unoperated cataract. Risk factor analyses for unoperated
uT5sLpA|6 cataract were not performed with the nursing home residents
=H'7g6 as information about risk factor exposure was not
k^|P8v+"D available for this cohort. The following factors were assessed
Kn]c4h}@b5 in relation to unoperated cataract: age, sex, residence
4{d`-reHg (urban/rural), language spoken at home (a measure of ethnic
=[O;/~J%: integration), country of birth, parents’ country of birth (a
C+B`A9 measure of ethnicity), years since migration, education, use
r?e)2l~C8j of ophthalmic services, use of optometric services, private
4v+4qyMyE health insurance status, duration of distance glasses use,
{DPobyvwFk glaucoma, age-related maculopathy and employment status.
yqpb_h9 In this cross sectional study it was not possible to assess the
Ea%}VZ&[ level of visual acuity that would predict a patient’s having
Kt,ENbF cataract surgery, as visual acuity data prior to cataract
aqTMOWyeu surgery were not available.
.\0PyV( The significant risk factors for unoperated cataract in univariate
<r*A(}Y analyses were related to: whether a participant had
[.}-n AN ever seen an optometrist, seen an ophthalmologist or been
)'{:4MX diagnosed with glaucoma; and participants’ employment
' LT6%<| status (currently employed) and age. These significant
YuWsE4$ factors were placed in a backwards stepwise logistic regression
Xa._ model. The factors that remained significantly related
l\W[WQPh to unoperated cataract were whether participants had ever
Vi~9[&.E\! seen an ophthalmologist, seen an optometrist and been
~eH+*U|\|M diagnosed with glaucoma. None of the demographic factors
mZVYgJQ[ were associated with unoperated cataract in the multivariate
L]o
5=K model.
gB!K{ Io' The per cent of participants with unoperated cataract
b??k|q who said that they were dissatisfied or very dissatisfied with
YadY?o./ Operated and unoperated cataract in Australia 79
Z9rs,_A Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
_
i )Z8# Age group Sex Urban Rural Nursing home Weighted total
pIh%5ZU (years) (%) (%) (%)
2nOoG/6
E 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
RHo|&.B;+ Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
6aG/=fq 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
iP1u u Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
EQ&E C 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
8$!/Zg Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
`F:PWG` 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
CCJ!;d;&87 Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
QKYGeT7&Y' 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
ruM16*S{= Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
24 S,w>j 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
'z\K0 Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
|5SYKA7CS Age-standardized
Lxm1.TOJ (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)
mqGp]'{ aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
{9KG06%+ their current vision was 30% (290/683), compared with 27%
iulM8"P
(26/95) of participants with prior cataract surgery (chisquared,
`Nnqdc2
1 d.f. = 0.25, P = 0.62).
Fl GKy9k Outcomes of cataract surgery
fSdv%$;Hc Two hundred and forty-nine eyes had undergone prior
IMzhEm cataract surgery. Of these 249 operated eyes, 49 (20%) were
GeN8_i[ left aphakic, 6 (2.4%) had anterior chamber intraocular
dX0A(6 lenses and 194 (78%) had posterior chamber intraocular
@W|}|V5 lenses. The rate of capsulotomy in the eyes with intact
;
pdW7 posterior capsules was 36% (73/202). Fifteen per cent of
vyT$IdV2 eyes (17/114) with a clear posterior capsule had bestcorrected
{{M?+]p,^ visual acuity of less than 6/12 compared with 43%
F(/^??<5 of eyes (6/14) with opaque capsules, and 15% of eyes
J?$4Yf (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
w5|az6wZB! P = 0.027).
$53I%. The percentage of eyes with best-corrected visual acuity
G8"L#[~ of 6/12 or better was 96% (302/314) for eyes without
;<%~g8:XL cataract, 88% (1417/1609) for eyes with prevalent cataract
$@q)IK%FDL and 85% (211/249) for eyes with operated cataract (chisquared,
&O(z|-&| x 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
f+Nq?GvwBQ operated eyes (11%) had visual acuities of less than 6/18
iUqL / (moderate vision impairment) (Fig. 2). A cause of this
]t]s/;9]K moderate visual impairment (but not the only cause) in four
p_=^E*J] (15%) eyes was secondary to cataract surgery. Three of these
[|V<e+>T/ four eyes had undergone intracapsular cataract extraction
J=W"FEXTL7 and the fourth eye had an opaque posterior capsule. No one
R
H^8 "%\ had bilateral vision impairment as a result of their cataract
+](^gaDw<L surgery.
?G+v#?A DISCUSSION
u!mUUFl To our knowledge, this is the first paper to systematically
-uN5DJSW assess the prevalence of current cataract, previous cataract
31k.{dnm surgery, predictors of unoperated cataract and the outcomes
;id0|x of cataract surgery in a population-based sample. The Visual
U$6N-q Impairment Project is unique in that the sampling frame and
N54U
[sy high response rate have ensured that the study population is
Ll lyx20U representative of Australians aged 40 years and over. Therefore,
SfQ,uD6 these data can be used to plan age-related cataract
>f4H<V- services throughout Australia.
828E^Q"< We found the rate of any cataract in those over the age
YmFJlMK of 40 years to be 22%. Although relatively high, this rate is
FkR9-X< significantly less than was reported in a number of previous
Hb=4k)-/] studies,2,4,6 with the exception of the Casteldaccia Eye
y^=\w?d Study.5 However, it is difficult to compare rates of cataract
BdB/`X* between studies because of different methodologies and
|/[?]` cataract definitions employed in the various studies, as well
V9NE kS as the different age structures of the study populations.
0Pu$1Fp Other studies have used less conservative definitions of
U)=?3}s( cataract, thus leading to higher rates of cataract as defined.
1XUsr;Wz In most large epidemiologic studies of cataract, visual acuity
su>GeJiPW has not been included in the definition of cataract.
U-#wFc2N Therefore, the prevalence of cataract may not reflect the
_CDUUr actual need for cataract surgery in the community.
XLz>h(w= 80 McCarty et al.
i&$L$zf, Table 2. Prevalence of previous cataract by age, gender and cohort
yYwZZa1 Age group Gender Urban Rural Nursing home Weighted total
IQf:aX (years) (%) (%) (%)
p)RASIB 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
AK%`EsI^ Female 0.00 0.00 0.00 0.00 (
CEq0ZL-W 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
uV`r_P Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
K[PH#dF5,x 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
R$k4}p Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
zMxHJNQ\D 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
ZH;VEX Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
;D&FZ|`(u 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
<SGO+1ztp Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
DKnjmZ:J| 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
{DJ!T Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
=7wI/5iN Age-standardized
?j9J6=2 (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)
=~6A c}$ Figure 2. Visual acuity in eyes that had undergone cataract
/ E}L%OvE surgery, n = 249. h, Presenting; j, best-corrected.
3cfW|J
Operated and unoperated cataract in Australia 81
0F> ils The weighted prevalence of prior cataract surgery in the
ej,j1iB Visual Impairment Project (3.6%) was similar to the crude
EKo!vieG rate in the Beaver Dam Eye Study4 (3.1%), but less than the
ui%B|b&& crude rate in the Blue Mountains Eye Study6 (6.0%).
kKL'rT6z However, the age-standardized rate in the Blue Mountains
^=`7]E [p Eye Study (standardized to the age distribution of the urban
CC&o pC Visual Impairment Project cohort) was found to be less than
djJD'JL the Visual Impairment Project (standardized rate = 1.36%,
F|pM$Kd` 95% CL 1.25, 1.47). The incidence of cataract surgery in
|`vwykhezO Australia has exceeded population growth.1 This is due,
>L[n4x\ perhaps, to advances in surgical techniques and lens
n'*4zxAA implants that have changed the risk–benefit ratio.
ehCGu(= The Global Initiative for the Elimination of Avoidable
5"5!\Zo Blindness, sponsored by the World Health Organization,
ZD!?mR+- states that cataract surgical services should be provided that
HXV4E\JA ‘have a high success rate in terms of visual outcome and
X.}i9a
6 improved quality of life’,17 although the ‘high success rate’ is
jMUd,j`Opx not defined. Population- and clinic-based studies conducted
;B*im
S10 in the United States have demonstrated marked improvement
'kBg3E$y in visual acuity following cataract surgery.18–20 We
g{PEplk found that 85% of eyes that had undergone cataract extraction
>s dT=6v had visual acuity of 6/12 or better. Previously, we have
n vzk P{ shown that participants with prevalent cataract in this
RTC;Wj cohort are more likely to express dissatisfaction with their
RvQa&r5l current vision than participants without cataract or participants
rfo7\'yk with prior cataract surgery.21 In a national study in the
T.d1? United States, researchers found that the change in patients’
Y#e,NN ratings of their vision difficulties and satisfaction with their
'#<4oW\] vision after cataract surgery were more highly related to
W*2d!/;7> their change in visual functioning score than to their change
jD
}G9=[$1 in visual acuity.19 Furthermore, improvement in visual function
?iXN..6x has been shown to be associated with improvement in
Nyx)&T&I overall quality of life.22
[D%(Y
~2 A recent review found that the incidence of visually
[?>\] significant posterior capsule opacification following
lcVZ 32MQ cataract surgery to be greater than 25%.23 We found 36%
|hl:!j.t capsulotomy in our population and that this was associated
Wn%b}{9Fb with visual acuity similar to that of eyes with a clear
WuuF&0?8C capsule, but significantly better than that of eyes with an
;cEoc(<? opaque capsule.
,>p1:pga A number of studies have shown that the demand and
7Is:hx|: timing of cataract surgery vary according to visual acuity,
WAt= T3 degree of handicap and socioeconomic factors.8–10,24,25 We
!S~0T!afF have also shown previously that ophthalmologists are more
Gf=3h4 likely to refer a patient for cataract surgery if the patient is
;rRV=$y employed and less likely to refer a nursing home resident.7
C4aAPkcp2$ In the Visual Impairment Project, we did not find that any
-e4TqzRr particular subgroup of the population was at greater risk of
9Iu"DOxX% having unoperated cataract. Universal access to health care
[H[L};%=j in Australia may explain the fact that people without
xp? YM35 Medicare are more likely to delay cataract operations in the
hmkm^2 USA,8 but not having private health insurance is not associated
!,|-{": with unoperated cataract in Australia.
72CHyl`|l In summary, cataract is a significant public health problem
YK\pV'&+ in that one in four people in their 80s will have had cataract
q|{z9V< surgery. The importance of age-related cataract surgery will
QWc,JCu
increase further with the ageing of the population: the
uUiS:Tp] number of people over age 60 years is expected to double in
Ht:\
z;cu the next 20 years. Cataract surgery services are well
'}^qz#w
accessed by the Victorian population and the visual outcomes
b
vOnS0,y of cataract surgery have been shown to be very good.
G@KDRv These data can be used to plan for age-related cataract
ppo0DC\> surgical services in Australia in the future as the need for
0xx4rpH cataract extractions increases.
"F =NDF ACKNOWLEDGEMENTS
Pr:\zI The Visual Impairment Project was funded in part by grants
&) 64:l& from the Victorian Health Promotion Foundation, the
.{t*v6(TP National Health and Medical Research Council, the Ansell
{+m8^-T Ophthalmology Foundation, the Dorothy Edols Estate and
Y7zs)W8xTT the Jack Brockhoff Foundation. Dr McCarty is the recipient
#UE}JR3g of a Wagstaff Fellowship in Ophthalmology from the Royal
wfv\xHG Victorian Eye and Ear Hospital.
C1fd@6 REFERENCES
*u-$$@|y 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
eR,/}g\ Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
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