Effect of laparoscopic Roux-en-Y gastric bypass surgery on hemoglobin A1c levels in diabetic patients: a matched-cohort analysis.
BACKGROUND
Elevated hemoglobin A1c (HbA1c) values are known to increase the risk of diabetic retinopathy, nephropathy, and peripheral neuropathy. The current guidelines recommend maintaining HbA1c values at <7%. We assessed the effect of laparoscopic Roux-en-Y gastric bypass surgery (LRYGB) on HbA1c values in diabetic patients compared with a conventionally treated cohort.


METHODS
A retrospective review of a prospective bariatric database identified diabetic patients who had undergone LRYGB from 2001 to 2005. A cohort of conventionally treated obese (body mass index >35 kg/m(2)) diabetic patients was matched by age and gender. The inclusion criteria consisted of a preoperative/initial HbA1c and 2 postoperative/follow-up HbA1c values compiled from our institution's comprehensive electronic medical record system. The patients in the LRYGB cohort were also required to have had a 1-year postoperative weight recorded. Statistical analysis was performed using the Student t test.


RESULTS
Each cohort consisted of 40 women (78.4%) and 11 men (21.6%). The mean age was 48.8 +/- 8.3 years for the surgical cohort and 48.2 +/- 8.3 years for the conventionally treated cohort. The mean body mass index was 47.7 +/- 5.7 kg/m(2) preoperatively for the surgical cohort and 45.1 +/- 5.7 kg/m2 initially for the conventionally treated cohort. The mean preoperative/initial HbA1c was 7.5% +/- 1.4% and 7.0% +/- 1.1% for the surgical and conventionally treated groups, respectively. At 1 year, HbA1c results were available for 46 LRYGB and 41 conventionally treated patients. The corresponding mean HbA1c values were 5.8% +/- 1.1% and 7.0% +/- .9% (P = .001). At 3 years, the mean HbA1c was 6.1% +/- 1.2% and 7.8% +/- 1.5% for 28 surgical and 36 conventionally treated patients, respectively (P = .001). The surgical patients' use of oral hypoglycemic medications and/or insulin decreased from 84.3% before surgery to 22.4% at 1 year postoperatively.


CONCLUSIONS
The patients who underwent LRYGB had a significant and sustained improvement in the HbA1c value compared with the conventionally treated obese patients with type 2 diabetes mellitus.
Mumme
Daniel E
DE
Surgery Residency, Gundersen Lutheran Medical Foundation, La Crosse, Wisconsin 54601, USA.
Mathiason
Michelle A
MA
Kallies
Kara J
KJ
Kothari
Shanu N
SN
D016009:Chi-Square Distribution; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000378:metabolism / Q000517:prevention & control*; D005260:Female; D015390:Gastric Bypass / Q000379:methods*; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D010535:Laparoscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000378:metabolism / Q000601:surgery*; D012074:Remission Induction; D012189:Retrospective Studies; D016896:Treatment Outcome; D015431:Weight Loss
D006442:Glycated Hemoglobin