Exposure to Chlamydia pneumoniae Infection and Progression of Age-related Macular Degeneration

• Published in: American journal of epidemiology Vol. 161; no. 11; pp. 1013 - 1019
• Main Authors: Robman, Luba, Mahdi, Olaimatu, McCarty, Catherine, Dimitrov, Peter, Tikellis, Gabriella, McNeil, John, Byrne, Gerald, Taylor, Hugh, Guymer, Robyn
• Format: Journal Article
• Language: English
• Published: Cary, NC Oxford University Press 01.06.2005; Oxford Publishing Limited (England)
• Subjects: age-related macular degeneration; Aged; Aged, 80 and over; Aging; AMD; Analysis. Health state; and Age-related Maculopathy Trial; Antibodies, Bacterial - analysis; Biological and medical sciences; Cataract; Chlamydiaceae Infections - complications; Chlamydophila pneumoniae; Chlamydophila pneumoniae - pathogenicity; Disease Progression; Enzyme-Linked Immunosorbent Assay; Epidemiology; Female; General aspects; Humans; infection; Infections; Macular degeneration; Macular Degeneration - microbiology; Macular Degeneration - pathology; Male; Medical sciences; Middle Aged; Ophthalmology; Public health. Hygiene; Public health. Hygiene-occupational medicine; Retinopathies; Risk Factors; VECAT; Vitamin E; Australia; Oceania; Human; Chlamydia pneumoniae; Retinopathy; Prognosis; Chlamydiaceae; Disease; Maculopathy; Exposure; disease progression; Epidemiology; Macular degeneration; Infection; Eye disease; Bacteriosis; Chlamydiales; Bacteria; Evolution; Chlamydiosis; Elderly; Public health; Chlamydophila pneumoniae
• ISSN: 0002-9262; 1476-6256
• DOI: 10.1093/aje/kwi130

Recent studies have found an association between exposure to Chlamydia pneumoniae infection and risk of age-related macular degeneration (AMD). To assess a potential risk of AMD progression posed by exposure to C. pneumoniae, the authors reexamined Australian residents in 2001–2002 who were aged 51–89 years with early AMD at baseline (1992–1995). Examination included macular photography and an enzyme-linked immunosorbent assay to determine antibody titers to the elementary bodies from C. pneumoniae AR39. AMD progression was assessed quantitatively, using both coarse and fine progression steps following an international classification for AMD grading, and also qualitatively, by side-by-side comparison of baseline and follow-up macular photographs. Serologic data were available for 246 of 254 (97%) subjects. AMD progression was associated with a higher antibody titer. After adjustment for age, smoking, family history of AMD, history of cardiovascular diseases, and source study, the subjects in the upper tertiles of antibody titers were 2.1 (95% confidence interval: 0.92, 4.69), 2.6 (95% confidence interval: 1.24, 5.41), and 3.0 (95% confidence interval: 1.46, 6.37) times more at risk of progression than those in the lowest tertile, using three definitions of progression, respectively. The fact that seroreactivity to C. pneumoniae was independently associated with the risk of AMD progression suggests that C. pneumoniae infection may be an additional risk factor for AMD progression.