THE WORLD-WIDE EFFECTS OF GLAUCOMA
Rohit Varma, MD, MPH
Cataract is the
leading cause of Blindness in the world with over 30 million persons
affected by it. The second leading cause in the past was trachoma.
However, with improvements in prevention and treatment, trachoma
is on the decline. In contrast, Glaucoma (Open-angle and Angle
Closure) is currently the second leading cause of blindness and
given the aging population in both the developed and developing
world, the prevalence of Glaucoma is increasing. It is estimated,
that in 2000, 66.8 million persons in the world have Glaucoma
(Open angle and Angle Closure) and 7.6 million of them are bilaterally
blind based primarily on visual acuity measurement. The level
of disability associated with glaucoma due to unilateral blindness
and peripheral field loss has not been evaluated carefully. This
is particularly important since recent data suggest that restriction
in activities of daily living and accidental falls are associated
with visual field loss.
The following
tables and figure provide some estimates of open angle glaucoma
and angle closure glaucoma and are adapted from Elolia
and Stokes (www.hc-sc.gc.ca/pphb-dgspsp/publicat/cdic-mcc/19-4/d_e.html).
Age, gender and race/ethnicity specific data are also provided.
These data have then been synthesized into worldwide estimates(2).
Table 1
Prevalence Rates of Open Angle Glaucoma in
Some Population-based Studies
| Study
(Year) |
Age group |
N |
No of
cases |
Prevalence rate |
| |
|
|
|
|
| Framingham, MA
(1973–1975) |
52–85 |
2433 |
28 |
1.4 |
| Roscommon, Ireland
(1990) |
>50 |
2186 |
41 |
1.9 |
| Casteldaccia, Italy
(before
1992) |
>40 |
1062 |
13 |
1.2 |
| Ponza, Italy
(1986) |
>40 |
1034 |
26 |
2.5 |
| Beaver Dam, WI
(1988–1990)
|
43–84 |
4926 |
104 |
2.1 |
| Baltimore, MD
(1985–1988) |
>40
White
Black |
5308
2913
2395 |
132
32
100 |
2.5
1.1
4.2 |
| Barbados
(1988–1992) |
40–84, AC |
4631 |
309 |
6.7 |
| St. Lucia |
>30 |
1679 |
147 |
8.8 |
| Japan
(1988–1989) |
>40 |
8126 |
213 |
2.6 |
| Mongolia
(1995) |
>40 |
942 |
5 |
0.5 |
| Mamre, South Africa (1992) |
>40 |
987 |
15 |
1.5 |
| Blue Mountains, Australia
(1992–1994) |
>49 |
3654 |
108 |
3.0 |
| Andhra Pradesh, India (1998-2000)
|
>30 |
1399 |
27 |
1.62 |
| Melbourne, Australia |
>40 |
3271 |
72 |
2.2 |
|
Tucson, AZ
(1997-1999) |
>40 |
4774 |
94 |
1.97 |
Table
2 Age-Specific Prevalence Rates of Open Angle Glaucoma
| Study |
Age group |
Prevalence (%) |
| Baltimore, MD.
(European) |
|
|
40–49 |
0.9 |
| 50–59 |
0.4 |
|
60–69 |
0.9 |
| 70–79 |
2.9 |
|
80+ |
2.2 |
| Total |
1.3 |
| Baltimore, MD
(African-
American) |
|
| 40–49 |
1.2 |
| 50–59 |
4.1 |
| 60–69 |
5.5 |
| 70–79 |
9.2 |
| 80+ |
11.3 |
| Total |
4.7 |
|
Barbados |
40–49 |
1.4 |
|
50–59 |
4.1 |
|
60–69 |
6.7 |
|
70–79 |
14.8 |
|
80+ |
23.2 |
|
Total |
6.8
|
| Andhra Pradesh, India |
30-39 |
0.22 |
| 40-49 |
1.26 |
| 50-59 |
2.31 |
| 60-69 |
4.89 |
| 70+ |
6.32 |
| Total |
1.62
|
| Tucson, AZ |
41-49 |
0.5 |
|
50-59 |
0.59 |
|
60-69 |
1.73 |
|
70-79 |
5.66 |
|
80-89 |
12.02 |
|
90+ |
20 |
|
Total |
1.97
|
| Japan |
30–49 |
1.0 |
| 50–69 |
2.6 |
| 70+ |
5.3 |
| Total 2.5 |
| TABLE 3
Prevalence of primary
angle-closure glaucoma |
| Study
(Year) |
Age
group |
N |
No of
cases |
Crude
prevalence
(%) |
| Beaver Dam, US
(1988–1990) |
43–84 |
4926 |
2 |
0.04 |
| Roscommon, Ireland
(1990) |
|
