9
Freeman, Cataract Surgery and Age-Related Macular Degeneration
The general characteristics of the three study populations are presented in Table 1. The
SEE population was more likely to be white, to have had more formal education, to be current
smokers, and because they were older (selected to be age 65 to 84), they were more likely to
have had previous cataract surgery and late AMD compared to the PVER and BES populations.
The proportion of blacks in BES was high (42%) due to the sampling strategy. BES participants
had the highest proportion of current smokers at 39%. Late AMD was rare in the three studies
with 73 cases in SEE, 53 in PVER, and 48 in BES.
The characteristics of those who had cataract surgery in at least 1 eye compared to those
who did not for the three studies are shown in Table 2. Individuals who had undergone cataract
surgery were older and were more likely to be white. In addition, those who did not have cataract
surgery in SEE were more likely to have never smoked.
The age and race-specific late AMD prevalence rates for the study populations are
presented in Table 3. The prevalence of late AMD tended to increase with age in the Caucasian
population. This was not obviously so in the African-American population, although there were
very small numbers of cases in the older age groups. African-Americans were less likely to have
late AMD compared to Caucasians and Hispanics.
Cataract Surgery, Severe Cataract, and AMD
The three datasets consistently showed that previous cataract surgery was associated with
an increased prevalence of late AMD, although they differed in the magnitude of the point
estimates and none of them were individually statistically significant (Table 4). An analysis of
the three data sets combined together revealed an odds ratio for previous cataract surgery of 1.7,
which was statistically significant (95% CI 1.1-2.6) (Table 4). In addition, having a severe
cataract in the eye at the time of the clinic exam was also associated with a higher odds of AMD
