Cataract surgery and the 5-year incidence of late-stage age-related maculopathy: pooled findings from the Beaver Dam and Blue Mountains eye studies.

PURPOSE

To assess whether cataract surgery in older persons increases risk for the development of late-stage age-related maculopathy (ARM).

DESIGN

Combined analysis of longitudinal data from two population-based cohorts, the Beaver Dam Eye Study and Blue Mountains Eye Study.

PARTICIPANTS

The Beaver Dam Eye Study examined 4926 persons aged 43 years or older at baseline and re-examined 3684 after 5 years. The Blue Mountains Eye Study examined 3654 persons aged 49 years or older at baseline and re-examined 2335 after 5 years.

METHODS

The two studies used similar protocols for retinal photography and photographic grading. We defined incident late-stage ARM as the development of neovascular ARM or geographic atrophy in eyes without either lesion type at baseline that was confirmed by consensus between the study investigators. Nonphakic eyes included eyes that were aphakic or pseudophakic at baseline. Eye-specific data were analyzed. Age- and study site-adjusted relative risks were calculated using the Cochran-Mantel-Haenszel method. Multivariate-adjusted odds ratios (ORs) were also estimated using generalized estimating equation models.

RESULTS

Of the 6019 participants examined after 5 years, 11,391 eyes were considered at risk for developing late-stage ARM, including 315 nonphakic and 11,076 phakic eyes. Late-state ARM (either neovascular ARM or geographic atrophy) developed in 6.0% to 7.5% of nonphakic eyes (10 of 168 right and 11 of 147 left eyes), compared with 0.7% of phakic eyes (40 of 5504 right and 37 of 5572 left eyes) during the 5-year period. Age- and study site-adjusted 5-year relative risks were 2.8 (95% confidence interval [CI], 1.6-5.1) for right and 3.7 (95% CI, 2.1-6.4) for left eyes. After further adjustment for gender, smoking, and the presence of indistinct or reticular drusen or pigmentary abnormalities at baseline, nonphakic eyes had a substantially higher risk for developing either late-stage ARM lesion compared with phakic eyes, OR = 5.7 (95% CI, 2.4-13.6).

CONCLUSIONS

Pooled findings from these two large population-based cohorts support the hypothesis that cataract surgery in older persons may be associated with an increased subsequent risk for developing late-stage ARM, particularly neovascular ARM.