Determinants of Evolution of Glomerular Filtration Rate After Bariatric Surgery: a 1-Year Observational Study.
Many studies have shown that hyperfiltration induced by obesity decreases after bariatric surgery, while others also showed an increase in glomerular filtration rate (GFR). Furthermore, the factors that influence GFR after bariatric surgery have been poorly studied. The objective was to study the impact of bariatric surgery on renal function and clarify the factors that determine the evolution of GFR after surgery.



We prospectively evaluated GFR (assessed with 24-h urinary clearance of creatinine) in all patients who underwent bariatric surgery between 2004 and 2014, before and 1 year after surgery. The links between GFR changes and usual clinical and biological parameters were studied.



Three hundred twenty-three patients with complete urine datasets were included (age 43 ± 11 year, M/F 49/274, BMI 46 ± 7 kg/m2). Excess weight loss was 61 ± 24 % and body surface area (BSA) decreased from 2.26 ± 0.23 to 1.98 ± 0.21 m2(p < 0.001). Mean GFR decreased from 133 ± 37 to 122 ± 49 ml/min (p < 0.001), in parallel to weight loss. However, GFR decreased in subjects with a preoperative GFR >120 ml/min (p < 0.001), was stable in those with 90 < GFR < 120 ml/min, and increased in those with GFR <90 ml/min (p < 0.01). In multivariate analysis, postoperative GFR did not correlate with metabolic parameters but correlated positively with BSA (p < 0.001) and protein intake (p < 0.01) and negatively with age (p < 0.001) and persistence of antihypertensive drugs (p < 0.001) after surgery.



GFR decreased after bariatric surgery in subjects with hyperfiltration, but increased in subjects with renal failure. Changes in body mass, protein intake, and blood pressure appeared to be the main determinants of GFR evolution after surgery.
Explorations Fonctionnelles, Centre de Référence de l'Obésité, Hôpital Louis Mourier (AP-HP), 178 rue des Renouillers, 92700, Colombes, France.|Université Denis Diderot, PRES Sorbonne Paris Cité, Paris, France.
Muriel
M
Coupaye
Université Denis Diderot, PRES Sorbonne Paris Cité, Paris, France.|Explorations Fonctionnelles, Hôpital Bichat (AP-HP), Paris, France.
Martin
M
Flamant
Explorations Fonctionnelles, Centre de Référence de l'Obésité, Hôpital Louis Mourier (AP-HP), 178 rue des Renouillers, 92700, Colombes, France.|Université Denis Diderot, PRES Sorbonne Paris Cité, Paris, France.
Ouidad
O
Sami
Université Denis Diderot, PRES Sorbonne Paris Cité, Paris, France.|Service de Chirurgie, Centre de Référence de l'Obésité, Hôpital Louis Mourier (AP-HP), 92700, Colombes, France.
Daniela
D
Calabrese
Université Denis Diderot, PRES Sorbonne Paris Cité, Paris, France.|Service de Chirurgie, Centre de Référence de l'Obésité, Hôpital Louis Mourier (AP-HP), 92700, Colombes, France.
Simon
S
Msika
Université Denis Diderot, PRES Sorbonne Paris Cité, Paris, France.|Service de Biochimie, Hôpital Louis Mourier (AP-HP), 92700, Colombes, France.
Catherine
C
Bogard
Université Denis Diderot, PRES Sorbonne Paris Cité, Paris, France.|Explorations Fonctionnelles, Hôpital Bichat (AP-HP), Paris, France.
Emmanuelle
E
Vidal-Petiot
Explorations Fonctionnelles, Centre de Référence de l'Obésité, Hôpital Louis Mourier (AP-HP), 178 rue des Renouillers, 92700, Colombes, France. severine.ledoux@lmr.aphp.fr.|Université Denis Diderot, PRES Sorbonne Paris Cité, Paris, France. severine.ledoux@lmr.aphp.fr.
Séverine
S
Ledoux
D000328:Adult; D050110:Bariatric Surgery; D001794:Blood Pressure; D003404:Creatinine / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000503:physiopathology / Q000601:surgery*; D011184:Postoperative Period; D012189:Retrospective Studies; D015431:Weight Loss / Q000502:physiology
D003404:Creatinine
Bariatric surgery; Creatinine clearance; Glomerular filtration rate; Obesity; Weight loss