The impact of bariatric surgery on estimated glomerular filtration rate in patients with type 2 diabetes: a retrospective cohort study

Research output: Contribution to journalArticlepeer-review


  • Nikhil Mirajkar
  • Srikanth Bellary
  • Mohamed Ahmed
  • Markos Daskalakis

External organisations

  • University of Birmingham


BACKGROUND: Diabetes mellitus is the most common cause of end-stage renal disease, which is associated with increased morbidity and mortality. The impact of bariatric surgery on chronic kidney disease is unclear.

OBJECTIVES: Our primary aim was to assess the impact of bariatric surgery on estimated glomerular filtration rate (eGFR) in type 2 diabetes (T2D) patients. Our secondary aim was to compare the impact of bariatric surgery versus routine care on eGFR in patients with T2D.

SETTING: University Hospital, United Kingdom.

METHODS: A retrospective cohort analysis of adults with T2D who underwent bariatric surgery at a single center between January 2005 and December 2012. Data regarding eGFR were obtained from electronic patients records. eGFR was calculated using the Modification of Diet in Renal Disease formula. Data regarding patients with T2D who did not undergo bariatric surgery ("routine care") were obtained from patients attending the diabetes clinic at the same center from 2009 to 2011.

RESULTS: One hundred sixty-three patients were included (mean age 48.5±8.8 yr; baseline body mass index 50.8±9.1 kg/m(2)) and were followed for 3.0±2.3 years. Bariatric surgery resulted in an improvement in eGFR (median [interquartile range] 86.0 [73.0-100.0] versus 92.0 [77.0-101.0] mL/min/1.73 m(2) for baseline versus follow-up, respectively; P = .003), particularly in patients with baseline eGFR≤60 mL/min/1.73 m(2) (48.0 [42.0-57.0] versus 61.0 [55.0-63.0] mL/min/1.73 m(2); P = .004). After adjusting for baseline eGFR, glycated hemoglobin (HbA1C), body mass index, age, and gender, bariatric surgery was associated with higher study-end eGFR compared with routine care (B = 7.787; P< .001).

CONCLUSION: Bariatric surgery results in significant improvements in eGFR in T2D patients, particularly those with an eGFR≤60 mL/min/1.73 m(2), while routine care was associated with a decline in eGFR.


Original languageEnglish
JournalSurgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery
Early online date8 Aug 2016
Publication statusE-pub ahead of print - 8 Aug 2016


  • Bariatric surgery , Type 2 diabetes , Chronic kidney disease , Nephropathy , Albuminuria , Renal function , Estimated glomerular filtration rate