Danish adults with type 2 diabetes and obesity who underwent Roux-en-Y gastric bypass were less likely to develop diabetic retinopathy compared with similar adults who did not undergo bariatric surgery, with no signs of “early worsening” retinopathy that can follow rapid diabetes improvement, according to findings published in Diabetic Medicine.
“In large-scale studies of mixed bariatric procedures, surgically induced remission of diabetes has shown beneficial effects on microvascular complications,” Lene Margrethe Ring Madsen, MD, of the department of endocrinology and internal medicine at Aarhus University in Denmark, and colleagues wrote. “However, because the improvement in blood glucose regulation has an immediate onset, the concern of ‘early worsening’ in retinopathy also applies to [Roux-en-Y gastric bypass].”
Madsen and colleagues performed a cross-sectional study with 96 adults with obesity and type 2 diabetes who underwent Roux-en-Y gastric bypass (mean age, 55.6 years; 78% women) between 2006 and 2011 in Denmark. The participants were registered in the Danish National Patient Registry. The researchers also recruited 48 adults with type 2 diabetes and obesity who did not have Roux-en-Y gastric bypass as controls (mean age, 56.6 years; 75% women) from Aarhus University Hospital.
During the study period of February to November 2017, the researchers compared the presence and development of retinopathy in both groups, as well as the effect of diabetes remission, by using graded fundus photography.
After adjustments for diabetes duration, age, sex and current BMI, participants in the Roux-en-Y gastric bypass group were at lower risk for developing retinopathy (RR = 0.82; 95% CI, 0.59-1.14) compared with the control group.
In the Roux-en-Y gastric bypass group, 52% of participants experienced diabetes remission, defined as an HbA1c of 6.5% or less with no antidiabetes medication or an HbA1c of 6% or less with metformin monotherapy. Of those, 12% developed retinopathy compared with 50% of the Roux-en-Y gastric bypass group that did not reach remission (P < .001). Compared with the control group, those experiencing diabetes remission had a lower risk for retinopathy (RR = 0.45; 95% CI, 0.19-1.06) compared with those without diabetes remission (RR = 0.94; 95% CI, 0.82-1.07).
The researchers further examined a subsample of 65 participants for whom fundus photography was available. Participants from the Roux-en-Y gastric bypass group did not show a change in retinopathy grading, but those in the control group had deteriorated grading (P < .001). The researchers noted that in the Roux-en-Y gastric bypass group, the risk for worsened retinopathy when compared with the control group was 0.26 (95% CI, 0.1-0.64). In addition, the risk for worsened retinopathy was slightly higher in those of the Roux-en-Y gastric bypass group who did not reach remission (RR = 0.27; 95% CI, 0.1-0.69) compared with those who did (RR = 0.13; 95% CI, 0.02-1.02). – by Phil Neuffer
Disclosures: The authors report no relevant financial disclosures.