ABSTRACT
Ssw&'B|o Purpose: To quantify the prevalence of cataract, the outcomes
:\mRtVH
of cataract surgery and the factors related to
"?P[9x} unoperated cataract in Australia.
G,=F<TnI' Methods: Participants were recruited from the Visual
'#A:.P Impairment Project: a cluster, stratified sample of more than
9s(i`RTM 5000 Victorians aged 40 years and over. At examination
mpAHL( sites interviews, clinical examinations and lens photography
Sl"BK0:%7 were performed. Cataract was defined in participants who
3 "Yif had: had previous cataract surgery, cortical cataract greater
ZjS(ad*.2 than 4/16, nuclear greater than Wilmer standard 2, or
+}
U2@03I posterior subcapsular greater than 1 mm2.
wd wp9 r Results: The participant group comprised 3271 Melbourne
3b@VY'P residents, 403 Melbourne nursing home residents and 1473
\Tyf *:_F> rural residents.The weighted rate of any cataract in Victoria
f TO+ZTRqf was 21.5%. The overall weighted rate of prior cataract
=JW[pRI5a surgery was 3.79%. Two hundred and forty-nine eyes had
f`?0WJ(M had prior cataract surgery. Of these 249 procedures, 49
oNIFx5*Z (20%) were aphakic, 6 (2.4%) had anterior chamber
`eC+% O
intraocular lenses and 194 (78%) had posterior chamber
t8/%Dgu intraocular lenses.Two hundred and eleven of these operated
~RInN+N# eyes (85%) had best-corrected visual acuity of 6/12 or
AkA!:!l better, the legal requirement for a driver’s license.Twentyseven
:6D0j (11%) had visual acuity of less than 6/18 (moderate
Y\(;!o0a vision impairment). Complications of cataract surgery
kiX%3( caused reduced vision in four of the 27 eyes (15%), or 1.9%
)xt4Wk/ of operated eyes. Three of these four eyes had undergone
Q'K$L9q intracapsular cataract extraction and the fourth eye had an
1TZPef^y opaque posterior capsule. No one had bilateral vision
1
i3k impairment as a result of cataract surgery. Surprisingly, no
=9$mbn
r particular demographic factors (such as age, gender, rural
XYAm
J residence, occupation, employment status, health insurance
0
iRR{a< status, ethnicity) were related to the presence of unoperated
>DP:GcTG cataract.
Qxt@V Conclusions: Although the overall prevalence of cataract is
9i%9
quite high, no particular subgroup is systematically underserviced
d!V$Y}n in terms of cataract surgery. Overall, the results of
!d8A cataract surgery are very good, with the majority of eyes
10O$'` achieving driving vision following cataract extraction.
URw5U1 Key words: cataract extraction, health planning, health
&{z<kmc$6 services accessibility, prevalence
@Y-TOCadT INTRODUCTION
iM5vrz`n Cataract is the leading cause of blindness worldwide and, in
Hg+
F^2<y Australia, cataract extractions account for the majority of all
y LM"+.?pL ophthalmic procedures.1 Over the period 1985–94, the rate
/;oqf4MF of cataract surgery in Australia was twice as high as would be
kg>>D expected from the growth in the elderly population.1
SlaDt Although there have been a number of studies reporting
-^SA8y the prevalence of cataract in various populations,2–6 there is
&tE.6^F little information about determinants of cataract surgery in
f /y` the population. A previous survey of Australian ophthalmologists
#/
"+ showed that patient concern and lifestyle, rather
lddp^ #f than visual acuity itself, are the primary factors for referral
GwLFL.Ke for cataract surgery.7 This supports prior research which has
s 3r=mp{ shown that visual acuity is not a strong predictor of need for
z$[C#5+2 cataract surgery.8,9 Elsewhere, socioeconomic status has
C@gXT]Q
0} been shown to be related to cataract surgery rates.10
|d}MxS`^ To appropriately plan health care services, information is
(OmH~lSO. needed about the prevalence of age-related cataract in the
p#@Z$gTH`' community as well as the factors associated with cataract
50~K,Jx6B surgery. The purpose of this study is to quantify the prevalence
L*JPe"N-e of any cataract in Australia, to describe the factors
@i%YNI5* related to unoperated cataract in the community and to
Qe$k3! describe the visual outcomes of cataract surgery.
ig_2={Q@ METHODS
-<f;l_( Study population
%y<]Yzv. Details about the study methodology for the Visual
:c]`D> Impairment Project have been published previously.11
pq!%?m] Briefly, cluster sampling within three strata was employed to
x\@*60o recruit subjects aged 40 years and over to participate.
L,]=vba'$ Within the Melbourne Statistical Division, nine pairs of
vqNsZ 8|` census collector districts were randomly selected. Fourteen
QIU,!w-3X nursing homes within a 5 km radius of these nine test sites
;4#D,z lO^ were randomly chosen to recruit nursing home residents.
C)RBkcb Clinical and Experimental Ophthalmology (2000) 28, 77–82
,FQK;BU!lh Original Article
uCP>y6I Operated and unoperated cataract in Australia
o>lmst%< Catherine A McCarty PhD, MPH, Mukesh B Nanjan PhD, Hugh R Taylor MD
[=%YV# O Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
lmCZ8 j(FF n Correspondence: Dr Cathy McCarty MPH, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne,
s0W2?!>) Victoria 3002, Australia. Email:
cathy@cera.unimelb.edu.au X% {'<baR 78 McCarty et al.
pW?&J>\6 Finally, four pairs of census collector districts in four rural
*cv}*D Victorian communities were randomly selected to recruit rural
!|G(Yg7C residents. A household census was conducted to identify
SU%DW 46 eligible residents aged 40 years and over who had been a
!?FK
We resident at that address for at least 6 months. At the time of
nCxAQ|P? the household census, basic information about age, sex,
/SR^C$h'I country of birth, language spoken at home, education, use of
[`_io>*g corrective spectacles and use of eye care services was collected.
@R2at Eligible residents were then invited to attend a local
)j&"%[2F examination site for a more detailed interview and examination.
\gO,hST The study protocol was approved by the Royal Victorian
#=,(JmQPt Eye and Ear Hospital Human Research Ethics Committee.
KLQ!b,=q Assessment of cataract
dZ(|uC!? A standardized ophthalmic examination was performed after
'c`
jyn pupil dilatation with one drop of 10% phenylephrine
"HIXm hydrochloride. Lens opacities were graded clinically at the
0t.p1 time of the examination and subsequently from photos using
oduDA: the Wilmer cataract photo-grading system.12 Cortical and
9s$U%F6} posterior subcapsular (PSC) opacities were assessed on
WQePSU retroillumination and measured as the proportion (in 1/16)
/!xF?OmVd of pupil circumference occupied by opacity. For this analysis,
A}VYb
:u/ cortical cataract was defined as 4/16 or greater opacity,
%@J1]E; PSC cataract was defined as opacity equal to or greater than
LLAa1Wq 1 mm2 and nuclear cataract was defined as opacity equal to
VM=+afY5M or greater than Wilmer standard 2,12 independent of visual
'\ DSTr:N acuity. Examples of the minimum opacities defined as cortical,
%b!-~
Y. nuclear and PSC cataract are presented in Figure 1.
m~l
F`? Bilateral congenital cataracts or cataracts secondary to
x8#ODuH intraocular inflammation or trauma were excluded from the
9uB(Mx(-:` analysis. Two cases of bilateral secondary cataract and eight
7,$z;Lr0S cases of bilateral congenital cataract were excluded from the
]
Uc`J8p, analyses.
!fkep= A Topcon® SL5 photo slit-lamp (Topcon America Corp.,
:Ao!ls'= Paramus, NJ, USA) with a 0.1 mm slit beam of 9.0 mm in
g[z.*y/ height set to an incident angle of 30° was used for examinations.
GUB`|
is^ Ektachrome® 200 ASA colour slide film (Eastman
]dPZ .r Kodak Company, Rochester, NY, USA) was used to photograph
deX5yrvOie the nuclear opacities. The cortical opacities were
.w?
.
ib( photographed with an Oxford® retroillumination camera
Uu p(6`7 (Marcher Enterprises Ltd, Hereford, UK) and T-MAX® 400
$a;]_ Y film (Eastman Kodak). Photographs were graded separately
9l/EjF^ by two research assistants and discrepancies were adjudicated
hq>Csj=
=@ by an independent reviewer. Any discrepancies
<g2_6C\j between the clinical grades and the photograph grades were
J
u` [m resolved. Except in cases where photographs were missing,
GJ(d&o8 the photograph grades were used in the analyses. Photograph
V L( < grades were available for 4301 (84%) for cortical
WgGm#I>K
cataract, 4147 (81%) for nuclear cataract and 4303 (84%)
-#&kYK#Ph for PSC cataract. Cataract status was classified according to
kUHE\L.Y] the severity of the opacity in the worse eye.
^C^*,V3 Assessment of risk factors
p#8W#t$ A standardized questionnaire was used to obtain information
=(r*
5vd about education, employment and ethnic background.11
|PVt}*0" Specific information was elicited on the occurrence, duration
Zy"=y+e!E; and treatment of a number of medical conditions,
g<*jlM1r including ocular trauma, arthritis, diabetes, gout, hypertension
OJ>.-" and mental illness. Information about the use, dose and
zzpZ19"`1 duration of tobacco, alcohol, analgesics and steriods were
3HV%4nZLf collected, and a food frequency questionnaire was used to
<|6%9@ determine current consumption of dietary sources of antioxidants
!3&kQpF and use of vitamin supplements.
]n1dp2aH Data management and statistical analysis
*6ZCDm&N Data were collected either by direct computer entry with a
>O9sk questionnaire programmed in Paradox© (Carel Corporation,
j}HFs0<L Ottawa, Canada) with internal consistency checks, or
QOFvsJ<s on self-coding forms. Open-ended responses were coded at
"`tXA a later time. Data that were entered on the self-coded forms
#} ,x @]p were entered into a computer with double data entry and
P~C rtTss reconciliation of any inconsistencies. Data range and consistency
Z)<
wv&K checks were performed on the entire data set.
Xh3; SAS© version 6.1 (SAS Institute, Cary, North Carolina) was
x!TZ0fq0 employed for statistical analyses.
H-t|i Ninety-five per cent confidence limits around the agespecific
pgc3j
P! rates were calculated according to Cochran13 to
Qc-(*} account for the effect of the cluster sampling. Ninety-five
+=@ ^i' per cent confidence limits around age-standardized rates
7v~j=Z> were calculated according to Breslow and Day.14 The strataspecific
x!7yU_ls` data were weighted according to the 1996
-e -e9uP Australian Bureau of Statistics census data15 to reflect the
9t:] cataract prevalence in the entire Victorian population.
D#rrW?-z Univariate analyses with Student’s t-tests and chi-squared
GuQRn tests were first employed to evaluate risk factors for unoperated
.-I|DVHe cataract. Any factors with P < 0.10 were then fitted
w<wV]F* into a backwards stepwise logistic regression model. For the
sRRI3y@ Figure 1. Minimum levels of cortical (a), nuclear (b), and posterior subcapsular (c) cataract.
Mhpdaos final multivariate models, P < 0.05 was considered statistically
HxwlYx,4 significant. Design effect was assessed through the use
V^fV7hw< of cluster-specific models and multivariate models. The
0&w0aP`Y design effect was assumed to be additive and an adjustment
2ypIq made in the variance by adding the variance associated with
70gg4BS the design effect prior to constructing the 95% confidence
D,;\F,p limits.
P~7.sM RESULTS
wz(K*FP Study population
'5.\#=S 1 A total of 3271 (83%) of the Melbourne residents, 403
1=GI&f2I (90%) Melbourne nursing home residents, and 1473 (92%)
E%pz9gcSx rural residents participated. In general, non-participants did
MgJ5B(
c not differ from participants.16 The study population was
&y.dmW representative of the Victorian population and Australia as
)m#']c:rg a whole.
?-~I<f]_ The Melbourne residents ranged in age from 40 to
.KA V) So" 98 years (mean = 59) and 1511 (46%) were male. The
=:7$/T'Qg Melbourne nursing home residents ranged in age from 46 to
{w5Z7s0 101 years (mean = 82) and 85 (21%) were men. The rural
~l4f{uOD>] residents ranged in age from 40 to 103 years (mean = 60)
mUXk9X%n and 701 (47.5%) were men.
[#b2%G1 Prevalence of cataract and prior cataract surgery
%$X\" As would be expected, the rate of any cataract increases
AlX3Wv} dramatically with age (Table 1). The weighted rate of any
g:~+Pe cataract in Victoria was 21.5% (95% CL 18.1, 24.9).
%v=!'?VT Although the rates varied somewhat between the three
xy^1US,L1 strata, they were not significantly different as the 95% confidence
Jq1 n0O limits overlapped. The per cent of cataractous eyes
C3"&sdLb$ with best-corrected visual acuity of less than 6/12 was 12.5%
__\P`S_ (65/520) for cortical cataract, 18% for nuclear cataract
WmVVR>0V| (97/534) and 14.4% (27/187) for PSC cataract. Cataract
;h=S7M9
. surgery also rose dramatically with age. The overall
7'j9rmTXs weighted rate of prior cataract surgery in Victoria was
;93KG4a 3.79% (95% CL 2.97, 4.60) (Table 2).
YKx 1NC Risk factors for unoperated cataract
CT"Fk'B' Cases of cataract that had not been removed were classified
5si}i'in as unoperated cataract. Risk factor analyses for unoperated
UKs$W` cataract were not performed with the nursing home residents
OlGR<X as information about risk factor exposure was not
myvh@@N available for this cohort. The following factors were assessed
> V%Q O>C in relation to unoperated cataract: age, sex, residence
V5s&hZZYa (urban/rural), language spoken at home (a measure of ethnic
P|}\/}{` integration), country of birth, parents’ country of birth (a
#v/ry)2Y= measure of ethnicity), years since migration, education, use
K-@bwB7~s of ophthalmic services, use of optometric services, private
_E
x?Xk health insurance status, duration of distance glasses use,
2Ow<`[7 glaucoma, age-related maculopathy and employment status.
F
6&P ~H In this cross sectional study it was not possible to assess the
K%2I level of visual acuity that would predict a patient’s having
DQ_ 2fX~) cataract surgery, as visual acuity data prior to cataract
<.$,`m,
surgery were not available.
h AAU ecx The significant risk factors for unoperated cataract in univariate
x]'H jTqX analyses were related to: whether a participant had
<Kp+&(l,l ever seen an optometrist, seen an ophthalmologist or been
b%<jUY diagnosed with glaucoma; and participants’ employment
!E0fGh status (currently employed) and age. These significant
Rp4FXR jC factors were placed in a backwards stepwise logistic regression
npj5U/
model. The factors that remained significantly related
/j
%_t to unoperated cataract were whether participants had ever
[x$;Xq
A seen an ophthalmologist, seen an optometrist and been
sH@ &* diagnosed with glaucoma. None of the demographic factors
X|)Il8 were associated with unoperated cataract in the multivariate
gix>DHq$k model.
Cz[5Ug'V The per cent of participants with unoperated cataract
ck~ '`<7 who said that they were dissatisfied or very dissatisfied with
`\e'K56W6 Operated and unoperated cataract in Australia 79
Gl"wEL* Table 1. Prevalence of any cataracta (excluding previous cataract surgery) by age, gender and cohort
ChVY
Vx( Age group Sex Urban Rural Nursing home Weighted total
4K'|DO|dH (years) (%) (%) (%)
ku-cn2M/ 40–49 Male 2.56 4.04 0.00 3.00 (1.91, 4.08)
ULck Female 2.61 1.70 0.00 2.36 (1.61, 3.10)
R/rcXX7% 50–59 Male 7.69 6.94 0.00 7.47 (5.80, 9.15)
Tz2x9b\82 Female 6.67 7.56 0.00 6.92 (5.60, 8.24)
-BjEL; 60–69 Male 20.7 25.0 10.0 22.0 (18.1, 26.0)
u{pTva Female 27.9 35.7 37.5 30.3 (26.0, 34.7)
J]\s*,C& 70–79 Male 43.1 58.7 39.1 48.1 (41.2, 55.1)
~Ji>[#W
K Female 58.6 66.2 55.6 61.0 (56.0, 65.9)
$'y1Po'2 80–89 Male 74.0 89.3 92.0 79.3 (72.3, 86.3)
W=F3XYS Female 91.9 97.0 80.2 92.6 (86.4, 98.8)
T77)Np 90 + Male 100.0 100.0 75.0 98.8 (96.2, 100.0)
#yX^?+Rc Female 100.0 100.0 93.8 98.6 (97.0, 100.0)
nHE
+p\ Age-standardized
'&/(oJ;O~ (95% CL) Combined 19.7 (16.3, 23.1) 23.2 (16.1, 30.2) 16.5 (2.06, 30.9) 21.5 (18.1, 25.0)
Zr5'TZ`$ aCortical > 4/16, nuclear > standard 2, posterior subcapsular > 1 mm2
EI<"DB their current vision was 30% (290/683), compared with 27%
VDPxue (26/95) of participants with prior cataract surgery (chisquared,
@H3|u`6V 1 d.f. = 0.25, P = 0.62).
+6uOg,; Outcomes of cataract surgery
8R&z3k;!t Two hundred and forty-nine eyes had undergone prior
Mi<*6j0 cataract surgery. Of these 249 operated eyes, 49 (20%) were
= SA
4\/
left aphakic, 6 (2.4%) had anterior chamber intraocular
#T
Z!#,q lenses and 194 (78%) had posterior chamber intraocular
J&( lenses. The rate of capsulotomy in the eyes with intact
`Nkx7Z~w: posterior capsules was 36% (73/202). Fifteen per cent of
T..-)kL+p eyes (17/114) with a clear posterior capsule had bestcorrected
pn+D@x#IA visual acuity of less than 6/12 compared with 43%
UnJi& ~O of eyes (6/14) with opaque capsules, and 15% of eyes
:u,2"] (11/73) with prior capsulotomies (chi-squared, 2 d.f. = 7.21,
O2/%mFS. P = 0.027).
>qr=l,Hi The percentage of eyes with best-corrected visual acuity
hU |LFjc of 6/12 or better was 96% (302/314) for eyes without
Ty)gPh6O cataract, 88% (1417/1609) for eyes with prevalent cataract
SB5@\^ and 85% (211/249) for eyes with operated cataract (chisquared,
9
Wxq) 2 d.f. = 22.3), P < 0.001). Twenty-seven of the
goG]WGVr operated eyes (11%) had visual acuities of less than 6/18
N)`tI0/W (moderate vision impairment) (Fig. 2). A cause of this
Z?vY3) moderate visual impairment (but not the only cause) in four
}Ox2olUX (15%) eyes was secondary to cataract surgery. Three of these
AEBw#v!,o four eyes had undergone intracapsular cataract extraction
V*0Y_ T{_
and the fourth eye had an opaque posterior capsule. No one
[RroHXdk+ had bilateral vision impairment as a result of their cataract
c }g$1of87 surgery.
@Z"QA!OK~c DISCUSSION
G:H(IA7Z To our knowledge, this is the first paper to systematically
0b!fWS?,k0 assess the prevalence of current cataract, previous cataract
Nj! R9N surgery, predictors of unoperated cataract and the outcomes
uOy\{5s8 of cataract surgery in a population-based sample. The Visual
h5h-}qBA Impairment Project is unique in that the sampling frame and
vLVSZX high response rate have ensured that the study population is
M$DwQ}Z representative of Australians aged 40 years and over. Therefore,
M}_M_ these data can be used to plan age-related cataract
C{lB/F/|! services throughout Australia.
w+:+r/!g We found the rate of any cataract in those over the age
f?oI'5R41 of 40 years to be 22%. Although relatively high, this rate is
Br?++
\ significantly less than was reported in a number of previous
F<XD^sO studies,2,4,6 with the exception of the Casteldaccia Eye
^ ^U)WB Study.5 However, it is difficult to compare rates of cataract
dW] Ej"W between studies because of different methodologies and
.>cL/KaP cataract definitions employed in the various studies, as well
hU=f?jo/ as the different age structures of the study populations.
`qQQQ.K7)z Other studies have used less conservative definitions of
y2d_b/ cataract, thus leading to higher rates of cataract as defined.
`K ~>!d_ In most large epidemiologic studies of cataract, visual acuity
c"jhbH!u4 has not been included in the definition of cataract.
D0"yZp} Therefore, the prevalence of cataract may not reflect the
zjhR9 actual need for cataract surgery in the community.
J0{WqA.P 80 McCarty et al.
J^e|"0d Table 2. Prevalence of previous cataract by age, gender and cohort
uvAy#, Age group Gender Urban Rural Nursing home Weighted total
&vGEz
*F (years) (%) (%) (%)
2R~=@ 40–49 Male 1.14 0.00 0.00 0.80 (0.00, 1.81)
Z2Y583D Female 0.00 0.00 0.00 0.00 (
c"_H%x<[ 50–59 Male 0.68 0.58 0.00 0.65 (0.13, 1.17)
E,nYtn|B Female 0.57 0.00 0.00 0.41 (0.00, 1.00)
_a:!U^4 60–69 Male 2.12 7.59 0.00 3.80 (1.41, 6.19)
'FvhzGn9Q Female 2.11 3.51 0.00 2.54 (1.81, 3.26)
RI<Yg# 70–79 Male 8.22 9.85 8.70 8.75 (6.38, 11.1)
4h0jX9 Female 7.21 7.86 7.02 7.41 (5.36, 9.46)
qhHRR/p 80–89 Male 25.0 30.0 14.3 26.2 (17.0, 35.4)
?F_;~ Female 27.9 25.6 18.3 26.7 (20.2, 33.3)
0C
i"tA3" 90 + Male 0.00 16.7 66.7 9.19 (0.00, 21.5)
znDtM1sLeV Female 58.3 100.0 26.9 63.1 (44.4, 81.8)
"Ezr- 4 Age-standardized
9jJ/ RX p (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)
E6d8z=X( Figure 2. Visual acuity in eyes that had undergone cataract
2ucsTh@ surgery, n = 249. h, Presenting; j, best-corrected.
*p<5(-J3 Operated and unoperated cataract in Australia 81
J7aK3he The weighted prevalence of prior cataract surgery in the
.]d
tRH< Visual Impairment Project (3.6%) was similar to the crude
"vHAp55B{ rate in the Beaver Dam Eye Study4 (3.1%), but less than the
():?FJM crude rate in the Blue Mountains Eye Study6 (6.0%).
<38@b
]+ However, the age-standardized rate in the Blue Mountains
, $F0D Eye Study (standardized to the age distribution of the urban
s%?p%2&RA Visual Impairment Project cohort) was found to be less than
q@!H^hd} the Visual Impairment Project (standardized rate = 1.36%,
38.J:?Q 95% CL 1.25, 1.47). The incidence of cataract surgery in
z4%F2Czai& Australia has exceeded population growth.1 This is due,
Bv|9{:1%X} perhaps, to advances in surgical techniques and lens
N[D\@
o implants that have changed the risk–benefit ratio.
+!Gr`&w*) The Global Initiative for the Elimination of Avoidable
_nCs$U Blindness, sponsored by the World Health Organization,
W;9X*I8f8 states that cataract surgical services should be provided that
,f""|X5 ‘have a high success rate in terms of visual outcome and
4I[FE;^ improved quality of life’,17 although the ‘high success rate’ is
u$ / ]59 not defined. Population- and clinic-based studies conducted
9Q5P7}%p in the United States have demonstrated marked improvement
~;4k UJD in visual acuity following cataract surgery.18–20 We
$}c@S0%P" found that 85% of eyes that had undergone cataract extraction
cg5{o|x had visual acuity of 6/12 or better. Previously, we have
:[rKSA]@ shown that participants with prevalent cataract in this
COJ!b cohort are more likely to express dissatisfaction with their
U[ungvU1U current vision than participants without cataract or participants
J^a"1| with prior cataract surgery.21 In a national study in the
Tsp-]
-) United States, researchers found that the change in patients’
;GEu.PdxB ratings of their vision difficulties and satisfaction with their
NjyIwo0 vision after cataract surgery were more highly related to
e{+{,g{iu their change in visual functioning score than to their change
:|mkI#P. in visual acuity.19 Furthermore, improvement in visual function
%hb5C 4q has been shown to be associated with improvement in
{!?RG\EYN overall quality of life.22
D}U<7=\3H A recent review found that the incidence of visually
-Dm
.z16 significant posterior capsule opacification following
[$Bb'],k cataract surgery to be greater than 25%.23 We found 36%
h4i$z-! capsulotomy in our population and that this was associated
?a9k5@s with visual acuity similar to that of eyes with a clear
meD (ja capsule, but significantly better than that of eyes with an
Ax*~[$$~% opaque capsule.
Czxrn2p/ A number of studies have shown that the demand and
?C2;:ol timing of cataract surgery vary according to visual acuity,
bD-Em#> degree of handicap and socioeconomic factors.8–10,24,25 We
X&8,.=kt"
have also shown previously that ophthalmologists are more
291|KG likely to refer a patient for cataract surgery if the patient is
nv{4
U}&P employed and less likely to refer a nursing home resident.7
5z>\'a1U In the Visual Impairment Project, we did not find that any
V gk
,+l!4 particular subgroup of the population was at greater risk of
%"^XxVJ* having unoperated cataract. Universal access to health care
~{Bi{aK2 in Australia may explain the fact that people without
B'/ >Ax& Medicare are more likely to delay cataract operations in the
/CE d14. USA,8 but not having private health insurance is not associated
4,DsB' with unoperated cataract in Australia.
NyLnE In summary, cataract is a significant public health problem
<J`xCm K in that one in four people in their 80s will have had cataract
*b_54X%3 surgery. The importance of age-related cataract surgery will
&2igX?60 increase further with the ageing of the population: the
-"H4brj;G number of people over age 60 years is expected to double in
XCriZ|s the next 20 years. Cataract surgery services are well
- S-1<xR accessed by the Victorian population and the visual outcomes
9#6/c of cataract surgery have been shown to be very good.
gAP}KR#T These data can be used to plan for age-related cataract
A,)ELVk1F surgical services in Australia in the future as the need for
^W'[l al. cataract extractions increases.
ulM&kw.4i ACKNOWLEDGEMENTS
xv l The Visual Impairment Project was funded in part by grants
=rF8[Q0K from the Victorian Health Promotion Foundation, the
V}-o):dI| National Health and Medical Research Council, the Ansell
#+k[[; 0 Ophthalmology Foundation, the Dorothy Edols Estate and
%m3efaC the Jack Brockhoff Foundation. Dr McCarty is the recipient
1bkUT_ of a Wagstaff Fellowship in Ophthalmology from the Royal
5zOSb$; Victorian Eye and Ear Hospital.
C<XDQ>? REFERENCES
Kf~+jYobO 1. Keeffe JE, Taylor HR. Cataract surgery in Australia 1985–94.
It-*CD9
Aust. N.Z. J. Ophthalmol. 1996; 24: 313–17.
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