Purpose: To determine if prior exposure to pathogens associated with vascular disease, cytomegalovirus, Chlamydia pneumoniae, and Helicobacter pylori correlates with neovascular age-related macular degeneration (AMD).
Design: An experimental study.
Setting: Institutional. Bascom Palmer Eye Institute, October 2001 to December 2002.
Patient population: 150 patients (47 neovascular amd, 36 dry amd, and 67 non-amd controls) were included in the study. exclusion criteria included hiv infection, malignancy, recent acute illness requiring hospitalization within 6 months, or immunosuppressive illness.
Procedure: Serum samples were obtained for analysis of cytomegalovirus, chlamydia pneumoniae, and helicobacter pylori igg antibody titers by elisa.
Main outcome measure: Comparison of the distribution of igg titers between patients with wet amd, dry amd, and controls.
Results: The average cytomegalovirus IgG titer was higher in patients with wet AMD versus controls (p = 0.02, Student t-test, two-tailed) and patients with dry AMD (p = 0.06). Twenty-six (55%) of 47 subjects with wet AMD had high cytomegalovirus IgG titers compared with 14 (39%) of 36 patients with dry AMD (odds ratio [OR] = 2.23, 95% confidence interval [CI] = 0.77 to 6.44) and 23 (34%) of 67 control patients (OR = 2.49, 95% CI = 0.98 to 6.33). There was no major difference in the distribution of titers for Chlamydia pneumoniae IgG and Helicobacter pylori IgG in wet and dry AMD patients. Five of 47 patients with wet AMD (11%) had high antibody titers to all three pathogens, compared with only 1 of 36 patients with dry AMD (3%) (OR = 4.17, 95% CI = 0.46 to 37.36).
Conclusions: There was a significant association of high cytomegalovirus IgG titer with neovascular AMD compared with dry AMD and control patients. Chronic infection with cytomegalovirus may be a novel risk factor for the progression from dry to neovascular AMD.