Author's Accepted Manuscript
The Effect of Bariatric Surgery on Renal Function Tirissa J. Reid MD, Saqib Saeed MD, Shiranda McCoy RPA-C, Adebola A. Osewa RN, FNP, Amrita Persaud MS, M.Ed, RD, Leaque Ahmed MD
www.elsevier.com/locate/buildenv
PII: DOI: Reference:
S1550-7289(14)00243-3 http://dx.doi.org/10.1016/j.soard.2014.02.048 SOARD2034
To appear in:
Surgery for Obesity and Related Diseases
Cite this article as: Tirissa J. Reid MD, Saqib Saeed MD, Shiranda McCoy RPA-C, Adebola A. Osewa RN, FNP, Amrita Persaud MS, M.Ed, RD, Leaque Ahmed MD, The Effect of Bariatric Surgery on Renal Function, Surgery for Obesity and Related Diseases, http://dx.doi.org/10.1016/j.soard.2014.02.048 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
The Effect of Bariatric Surgery on Renal Function Authors and affiliations: Tirissa J. Reid, MD1,2 Saqib Saeed, MD1 Shiranda McCoy, RPA-C1 Adebola A. Osewa, RN, FNP1 Amrita Persaud, MS, M.Ed, RD1 Leaque Ahmed, MD1,3 1
2
Dept of Surgery, Harlem Hospital, New York, NY, United States
Dept of Medicine, Columbia University, College of Physicians & Surgeons, New York, NY,
United States 3
Dept of Surgery, Columbia University, College of Physicians & Surgeons, New York, NY,
United States
Funding: None Corresponding Author: Tirissa J. Reid, MD 630 West 168th Street PH8W, Room 864 New York, NY 10032 (W): 212-305-5568, (C): 347-307-3619, Fax: 212-305-5420, e-mail:[email protected]
Effect of Bariatric Surgery on Renal Function 1
The Effect of Bariatric Surgery on Renal Function
The Effect of Bariatric Surgery on Renal Function
Abstract Background: Obesity is associated with albuminuria and impaired renal function. We previously reported on 38 non-diabetics with improved albuminuria after Roux-en-Y gastric bypass (RYGB).
Objectives: Evaluate changes in renal function, urinary-to-albumin-creatinine ratio (UACR) and glomerular filtration rate (GFR), in a larger cohort of patients with normal or mildly impaired renal function, undergoing RYGB or sleeve gastrectomy at 1 year post-op.
Setting: Public hospital in New York City, 2004-2011.
Methods: Retrospective study. Inclusions: patients with pre-operative and 1 yr post-operative serum and urine albumin and creatinine and weight (kg). Exclusions: pre-op CKD ≥ Stage 3 or macroalbuminuria (UACR ≥ 300 mg/g). Primary outcomes: changes in UACR and eGFR at 1 year.
Results: 158 patients met inclusion criteria; 91.8% female; mean age 40.8 yrs; 84.2% white Hispanic, 14.6 % African-American. Hypertension was present in 43.0%, diabetes mellitus in 28.5%. UACR was 21.5 ± 3.2 mg/g, decreasing to 10.2 ± 1.2 mg/g at 1 yr (p2 standard deviations above the mean GFR in healthy individuals. NHANES (1) data was used for the reference GFR of our population.
Subjects and Methods Study Subjects The study consisted of 158 patients who met NIH criteria (26) for bariatric surgery, body mass index (BMI) ≥ 40 or BMI ≥ 35 with weight-related comorbidities, and underwent RYGB or SG at a New York City public hospital from 2004-2011.
Study Design Retrospective review of electronic medical records was performed. Demographic, clinical and biochemical data were collected. Demographic data included age, gender, and race/ethnicity as defined by patients. Clinical data included date/type of bariatric surgery, height (cm) and weight 5
(kg), presence/absence of Type 2 diabetes mellitus (DM2), hypertension (HTN) or chronic kidney disease (CKD) ≥ Stage 3. Biochemical data included serum/urine creatinine and albumin. Inclusion criteria: pre-operative and 1 yr post-operative serum/urine creatinine and albumin, height/weight data. Exclusion criteria: pre-operative CKD ≥ Stage 3, macroalbuminuria (UACR ≥ 300 mg/g) or revisional bariatric surgery. Of 903 bariatric surgeries performed from 20042011, patients were excluded due to: absent pre-op urine microalbumin (178), absent 1 year postop urine microalbumin (504), revisional bariatric surgery (38), and gastric banding (25).
Primary outcomes: changes in urinary albumin-to-creatinine ratio and glomerular filtration rate at 1 year. Secondary outcomes: changes in prevalence of microalbuminuria (UACR of 30-299 mg/g) and hyperfiltration, baseline vs. 1 year post-op.
The study was approved by our hospital Institutional Review Board.
Biochemical Measurements Serum/urine creatinine were measured by modified Jaffe method (colorimetric). Serum albumin was measured by bromocresol green colorimetric assay. Urine microalbumin was measured by polyethylene glycol-enhanced immunoturbidimetric assay.
Statistical Analysis Body mass index (BMI) was calculated as: weight (kg)/height (m2) Urinary albumin-to-creatinine ratio was calculated as: urine albumin (mg)/urine creatinine (g) 6
GFR (mL/min) was estimated using the Cockcroft-Gault formula, modified for obese subjects using LBW (18) as follows: eGFR= Creatinine clearance = (140-age)*LBW*(.85 if female)/72*serum creatinine LBW for males = (9270 * total body weight) / (6680 + 216 * BMI) LBW for females = (9270 * total body weight) / (8780 + 244 * BMI) Statistical analyses were performed using GraphPad Prism v5.03 for Windows. Data are expressed as mean ± SE. Within group differences were tested by paired Student’s t-test and between group differences by Mann-Whitney U-test. Associations were tested using Pearson’s correlation coefficient test. A P-value
The Effect of Bariatric Surgery on Renal Function Tirissa J. Reid MD, Saqib Saeed MD, Shiranda McCoy RPA-C, Adebola A. Osewa RN, FNP, Amrita Persaud MS, M.Ed, RD, Leaque Ahmed MD
www.elsevier.com/locate/buildenv
PII: DOI: Reference:
S1550-7289(14)00243-3 http://dx.doi.org/10.1016/j.soard.2014.02.048 SOARD2034
To appear in:
Surgery for Obesity and Related Diseases
Cite this article as: Tirissa J. Reid MD, Saqib Saeed MD, Shiranda McCoy RPA-C, Adebola A. Osewa RN, FNP, Amrita Persaud MS, M.Ed, RD, Leaque Ahmed MD, The Effect of Bariatric Surgery on Renal Function, Surgery for Obesity and Related Diseases, http://dx.doi.org/10.1016/j.soard.2014.02.048 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
The Effect of Bariatric Surgery on Renal Function Authors and affiliations: Tirissa J. Reid, MD1,2 Saqib Saeed, MD1 Shiranda McCoy, RPA-C1 Adebola A. Osewa, RN, FNP1 Amrita Persaud, MS, M.Ed, RD1 Leaque Ahmed, MD1,3 1
2
Dept of Surgery, Harlem Hospital, New York, NY, United States
Dept of Medicine, Columbia University, College of Physicians & Surgeons, New York, NY,
United States 3
Dept of Surgery, Columbia University, College of Physicians & Surgeons, New York, NY,
United States
Funding: None Corresponding Author: Tirissa J. Reid, MD 630 West 168th Street PH8W, Room 864 New York, NY 10032 (W): 212-305-5568, (C): 347-307-3619, Fax: 212-305-5420, e-mail:[email protected]
Effect of Bariatric Surgery on Renal Function 1
The Effect of Bariatric Surgery on Renal Function
The Effect of Bariatric Surgery on Renal Function
Abstract Background: Obesity is associated with albuminuria and impaired renal function. We previously reported on 38 non-diabetics with improved albuminuria after Roux-en-Y gastric bypass (RYGB).
Objectives: Evaluate changes in renal function, urinary-to-albumin-creatinine ratio (UACR) and glomerular filtration rate (GFR), in a larger cohort of patients with normal or mildly impaired renal function, undergoing RYGB or sleeve gastrectomy at 1 year post-op.
Setting: Public hospital in New York City, 2004-2011.
Methods: Retrospective study. Inclusions: patients with pre-operative and 1 yr post-operative serum and urine albumin and creatinine and weight (kg). Exclusions: pre-op CKD ≥ Stage 3 or macroalbuminuria (UACR ≥ 300 mg/g). Primary outcomes: changes in UACR and eGFR at 1 year.
Results: 158 patients met inclusion criteria; 91.8% female; mean age 40.8 yrs; 84.2% white Hispanic, 14.6 % African-American. Hypertension was present in 43.0%, diabetes mellitus in 28.5%. UACR was 21.5 ± 3.2 mg/g, decreasing to 10.2 ± 1.2 mg/g at 1 yr (p2 standard deviations above the mean GFR in healthy individuals. NHANES (1) data was used for the reference GFR of our population.
Subjects and Methods Study Subjects The study consisted of 158 patients who met NIH criteria (26) for bariatric surgery, body mass index (BMI) ≥ 40 or BMI ≥ 35 with weight-related comorbidities, and underwent RYGB or SG at a New York City public hospital from 2004-2011.
Study Design Retrospective review of electronic medical records was performed. Demographic, clinical and biochemical data were collected. Demographic data included age, gender, and race/ethnicity as defined by patients. Clinical data included date/type of bariatric surgery, height (cm) and weight 5
(kg), presence/absence of Type 2 diabetes mellitus (DM2), hypertension (HTN) or chronic kidney disease (CKD) ≥ Stage 3. Biochemical data included serum/urine creatinine and albumin. Inclusion criteria: pre-operative and 1 yr post-operative serum/urine creatinine and albumin, height/weight data. Exclusion criteria: pre-operative CKD ≥ Stage 3, macroalbuminuria (UACR ≥ 300 mg/g) or revisional bariatric surgery. Of 903 bariatric surgeries performed from 20042011, patients were excluded due to: absent pre-op urine microalbumin (178), absent 1 year postop urine microalbumin (504), revisional bariatric surgery (38), and gastric banding (25).
Primary outcomes: changes in urinary albumin-to-creatinine ratio and glomerular filtration rate at 1 year. Secondary outcomes: changes in prevalence of microalbuminuria (UACR of 30-299 mg/g) and hyperfiltration, baseline vs. 1 year post-op.
The study was approved by our hospital Institutional Review Board.
Biochemical Measurements Serum/urine creatinine were measured by modified Jaffe method (colorimetric). Serum albumin was measured by bromocresol green colorimetric assay. Urine microalbumin was measured by polyethylene glycol-enhanced immunoturbidimetric assay.
Statistical Analysis Body mass index (BMI) was calculated as: weight (kg)/height (m2) Urinary albumin-to-creatinine ratio was calculated as: urine albumin (mg)/urine creatinine (g) 6
GFR (mL/min) was estimated using the Cockcroft-Gault formula, modified for obese subjects using LBW (18) as follows: eGFR= Creatinine clearance = (140-age)*LBW*(.85 if female)/72*serum creatinine LBW for males = (9270 * total body weight) / (6680 + 216 * BMI) LBW for females = (9270 * total body weight) / (8780 + 244 * BMI) Statistical analyses were performed using GraphPad Prism v5.03 for Windows. Data are expressed as mean ± SE. Within group differences were tested by paired Student’s t-test and between group differences by Mann-Whitney U-test. Associations were tested using Pearson’s correlation coefficient test. A P-value
