title: Impact of kidney function and urinary protein excretion on pulmonary function in Japanese patients with chronic kidney disease.
abstract: BACKGROUND
  Although the cardiorenal relationship in chronic kidney disease has been investigated, information about the lung-kidney relationship is limited. Here, we investigated the impact of kidney function and urinary protein excretion on pulmonary dysfunction.
  
  
  METHODS
  The data from pulmonary function tests and kidney function (estimated glomerular filtration rate [eGFR] and urinary protein) between 1 April 2005 and 30 June 2010 were selected from our laboratory database. Data were classified into 4 categories according to eGFR and proteinuria. Category 1, eGFR ≥60 ml/min/1.73 m(2) and urinary protein <0.3 g/gCr; category 2, eGFR <60 ml/min/1.73 m(2) and urinary protein <0.3 g/gCr; category 3, eGFR ≥60 ml/min/1.73 m(2) and urinary protein ≥0.3 g/gCr; and category 4, eGFR <60 ml/min/1.73 m(2) and urinary protein ≥0.3 g/gCr. Pulmonary function data were evaluated according to these 4 categories.
  
  
  RESULTS
  A total of 133 participants without major respiratory disease, abnormal computed tomography and smoking history were enrolled. Hemoglobin (Hb)-adjusted percentage carbon monoxide diffusing capacity (%DLCO) in category 4 (46.2 ± 7.5) and category 2 (63.6 ± 17.8) were significantly lower than in category 1 (75.8 ± 18.9) (P < 0.05). In addition, Hb-adjusted %DLCO was weakly correlated with eGFR in participants with urinary protein <0.3 g/gCr (R = 0.30, P = 0.001). Hb-adjusted %DLCO was strongly correlated with eGFR in participants with urinary protein ≥0.3 g/gCr (R = 0.81, P < 0.001). Other pulmonary function test markers (percentage (%) vital capacity, % forced expiratory volume in one second (FEV1), FEV1/forced vital capacity, % total lung capacity, and % residual volume) were not significantly different between categories.
  
  
  CONCLUSIONS
  This study suggests that decreased eGFR is associated with decreased %DLCO in proteinuric patients.
authors: Clinical Laboratory, Kanazawa University Hospital, Kanazawa, Japan.
authors: Yusuke
authors: Y
authors: Nakade
authors: Tadashi
authors: T
authors: Toyama
authors: Kengo
authors: K
authors: Furuichi
authors: Shinji
authors: S
authors: Kitajima
authors: Noriyuki
authors: N
authors: Ohkura
authors: Akihiro
authors: A
authors: Sagara
authors: Yasuyuki
authors: Y
authors: Shinozaki
authors: Akinori
authors: A
authors: Hara
authors: Kiyoki
authors: K
authors: Kitagawa
authors: Miho
authors: M
authors: Shimizu
authors: Yasunori
authors: Y
authors: Iwata
authors: Hiroyasu
authors: H
authors: Oe
authors: Mikio
authors: M
authors: Nagahara
authors: Hiroshi
authors: H
authors: Horita
authors: Yoshio
authors: Y
authors: Sakai
authors: Shuichi
authors: S
authors: Kaneko
authors: Takashi
authors: T
authors: Wada
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007564:Japan; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011507:Proteinuria / Q000503:physiopathology*; D051436:Renal Insufficiency, Chronic / Q000503:physiopathology*; D012129:Respiratory Function Tests