title: Cystatin C-based estimated glomerular filtration rate and periodontitis.
abstract: OBJECTIVE
  Accumulating evidence suggests that decreased kidney function characterised by low estimated glomerular filtration rate (eGFR) may be associated with periodontitis. Recent studies have suggested that the use of cystatin C strengthens the association between the eGFR and the risks of adverse outcomes in decreased kidney function. The aim of this cross-sectional study was to investigate the association of cystatin C-based eGFR (eGFRcys) and creatinine-based eGFR (eGFRcreat), the commonly used method to assess kidney function, with periodontitis in 502 Japanese women (average age, 68.6 years).
  
  
  METHODS
  GFR was estimated from serum cystatin C and serum creatinine, respectively, using the Japanese equation for GFR. Participants were classified into five groups according to their eGFRcys and eGFRcreat values. Poisson regression models with robust error variance assessed the associations of eGFRcys and eGFRcreat with periodontitis. Tests for trends were performed by fitting the five-category eGFR variables in their continuous form to the regression models.
  
  
  RESULTS
  Participants with eGFRcys < 50 ml/min/1.73 m(2) were at significantly higher risk of periodontitis compared with the reference group (≥90 ml/min/1.73 m(2) ) (adjusted relative risk = 2.12, 95% confidence interval = 1.12 to 4.02). Additionally, there was a trend towards a higher risk of periodontitis among participants with lower eGFRcys values (p for trend in the multivariable model = 0.008). In contrast, eGFRcreat did not show a significant association with periodontitis.
  
  
  CONCLUSIONS
  The findings of this study of Japanese older women showed that eGFRcys had a stronger and more linear association with periodontitis than eGFRcreat.
authors.affiliation: Division of Preventive Dentistry, Department of Oral Health Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Iwasaki
authors.affiliation: Department of Preventive and Restorative Dental Sciences, University of California San Francisco, San Francisco, CA, USA.
authors.forename: George W
authors.initials: GW
authors.lastname: Taylor
authors.affiliation: Division of Preventive Dentistry, Department of Oral Health Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Japan.
authors.forename: Misuzu
authors.initials: M
authors.lastname: Sato
authors.affiliation: Department of Preventive Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Japan.
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: Division of Oral Science for Health Promotion, Department of Oral Health and Welfare, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Yoshihara
authors.affiliation: Division of Preventive Dentistry, Department of Oral Health Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Miyazaki
mesh_terms: D000368:Aged; D003404:Creatinine; D003430:Cross-Sectional Studies; D055316:Cystatin C / Q000378:metabolism*; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D007564:Japan; D007674:Kidney Diseases / Q000150:complications*; D010518:Periodontitis / Q000209:etiology* / Q000503:physiopathology*
chemical_list: D055316:Cystatin C; D003404:Creatinine
keywords: aged; epidemiology; periodontal diseases; renal insufficiency