Obesity protects against diabetic retinopathy in type 2 diabetes
In patients with type 2 diabetes, obesity may be protective against vision-threatening diabetic retinopathy (DR), a recent Korea study has shown.
Researchers enrolled 887 participants with type 2 diabetes into a nationwide survey. Seven-field fundus photographs were used to evaluate for the presence and severity of DR, while body fat was measured using dual-energy X-ray absorptiometry.
Only 185 participants (median age, 63 years; 42.2 percent male) were diagnosed with DR, while the rest were not (n=702; median age, 65 years; 50.3 percent male). Body mass index (BMI; p=0.001) and waist circumference (p=0.024) were significantly greater in those without DR. This trend was reflected for total body fat, but significance was not achieved (p=0.102).
Multivariate logistic regression analysis showed that BMI (adjusted odds ratio [OR], 0.80, 95 percent CI, 0.70–0.92; p=0.001) and waist circumference (adjusted OR, 0.86, 0.79–0.92; p<0.001) were significantly correlated with a lower likelihood of vision-threatening DR.
Obesity remained significantly predictive against DR risk when the Asian BMI cutoff values were used (adjusted OR, 0.65, 0.43–0.99; p-trend=0.029), as well as when participants were divided into tertiles of waist circumference (highest vs lowest: adjusted OR, 0.54, 0.32–0.91; p-trend=0.009).
Stratification of all analyses according to sex showed that total body fat remained significantly associated with DR risk only in females (adjusted OR, 0.93, 0.88–0.98; p=0.009). No such effect was observed in males or with the other obesity indices used.