title: Aging and low-grade inflammation reduce renal function in middle-aged and older adults in Japan and the USA.
abstract: The objective of this study was to investigate the effects of low-grade inflammation on age-related changes in glomerular filtration rate (GFR) in middle-aged and older white Americans, African-Americans, and Japanese adults. Serum creatinine, C-reactive protein (CRP), and interleukin-6 (IL-6) levels were determined for 1570 adult participants in two surveys of aging in the USA and Japan (N = 1188 and 382, respectively). Kidney function declined with age in both countries and was associated with IL-6 and CRP. IL-6 and CRP also influenced the extent of the arithmetic bias when calculating the GFR using the chronic kidney disease epidemiology (CKD-EPI) formula with just serum creatinine. Younger African-Americans initially had the highest GFR but showed a steep age-related decrement that was associated with elevated inflammation. Japanese adults had the lowest average GFR but evinced a large effect of increased inflammatory activity when over 70 years of age. Importantly, our results also indicate that low-grade inflammation is important to consider when evaluating kidney function solely from serum creatinine.
authors.affiliation: University of Wisconsin, Madison, WI, USA.
authors.forename: Reagan
authors.initials: R
authors.lastname: Costello-White
authors.forename: Carol D
authors.initials: CD
authors.lastname: Ryff
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Coe
mesh_terms: D000328:Adult; D001741:Black or African American; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D044466:Asian People; D002097:C-Reactive Protein / Q000378:metabolism; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis / Q000453:epidemiology*; D014481:United States / Q000453:epidemiology; D044465:White People
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6; D002097:C-Reactive Protein