February 27, 2009 — Serum cystatin C level and chronic kidney disease may have a link to incidence of age-related macular degeneration (AMD) that is independent of smoking and other risk factors, according to a population-based cohort study reported in the February issue of the Archives of Ophthalmology.
"Serum cystatin C has been used to estimate glomerular filtration rate to define the presence of CKD," write Ronald Klein, MD, MPH, from the University of Wisconsin School of Medicine and Public Health, Madison, and colleagues. "It is abundant in retinal pigment epithelium (RPE) cells and has been hypothesized through its effects on cathepsins to have a role in the pathogenesis of AMD."
The goal of this study was to examine the associations of the serum cystatin C level and chronic kidney disease with the incidence and progression of AMD during 15 years of follow-up in 4926 participants of the Beaver Dam Eye Study.
The participants were residents of Beaver Dam, Wisconsin, and were 43 to 84 years old at the time of their baseline examination, which took place between March 1, 1988, and September 14, 1990. Follow-up examinations were done at 5-year intervals. The 15-year follow-up examination was performed from March 31, 2003, through April 30, 2005, and included 2119 survivors of the original study cohort.
