title: Tubular proteinuria is the dominant type of proteinuria in an elderly community population in China.
abstract: OBJECTIVE
  To explore the types of proteinuria in the elderly population in China.
  
  
  METHODS
  Seven hundred and fourteen elderly people (≥ 60 years old) from Tianjin, China, were selected for the study. The albumin-to-creatinine ratio and α1-microglobulin-to-creatinine ratio from morning urine samples were used as indicators of proteinuria. The prevalence of proteinuria was evaluated and the proportion of three different types of proteinuria (mixed, glomerular, and tubular) was assessed in the subjects by analyzing these indicators.
  
  
  RESULTS
  Of the 714 subjects, 29.13 % had elevated ACR and 46.36 % had elevated MCR. The proportion of subjects with either elevated ACR or MCR was 53.78 %. The correlation between MCR and ACR was moderate (r = 0.58, R (2) = 0.34, P < 0.001). Overall, tubular proteinuria was dominant (45.83 %), followed by mixed glomerular and tubular proteinuria (35.68 %), and significantly higher than glomerular proteinuria. A diet high in salt was the independent risk factor for tubular proteinuria; physical activity was the independent risk factor for glomerular proteinuria. The risk of glomerular proteinuria was lower in males than in females, but the risk of tubular proteinuria was higher in males.
  
  
  CONCLUSIONS
  The prevalence of tubular proteinuria was higher than that of glomerular proteinuria, and the risk factors are different, in the elderly in China; therefore, tubular damage markers should get more attention in the overall population.
authors.affiliation: Graduate School of Tianjin Medical University, Tianjin, People's Republic of China.
authors.forename: Hua-Bin
authors.initials: HB
authors.lastname: Wang
authors.forename: Qing-Hong
authors.initials: QH
authors.lastname: Yang
authors.forename: Xu
authors.initials: X
authors.lastname: Jiang
authors.forename: Xiao-Fan
authors.initials: XF
authors.lastname: Cui
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
mesh_terms: D000367:Age Factors; D000368:Aged; D002681:China / Q000453:epidemiology; D003404:Creatinine / Q000652:urine; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007684:Kidney Tubules / Q000378:metabolism*; D008297:Male; D011159:Population Surveillance; D015995:Prevalence; D011507:Proteinuria / Q000175:diagnosis / Q000453:epidemiology* / Q000652:urine; D012189:Retrospective Studies; D016482:Urinalysis
chemical_list: D003404:Creatinine