Abstract
Purpose: :
To determine the relationship between body mass index (BMI) and development of diabetic retinopathy (DR) in children with Type 1 diabetes (DM).
Methods: :
A retrospective chart review was conducted for all pediatric patients with type 1 diabetes (age<19 yrs) evaluated in the Beetham Eye Institute/Joslin Diabetes Center from 1/1/06-12/31/09. DR severity, hemoglobin A1c (HbA1c), blood pressure (BP), lipids, height and weight from each visit were recorded on standardized forms. Subjects were classified by BMI according to the CDC sex and age-adjusted growth curves as under/normal weight (BMI<85th percentile), overweight (BMI≥85th percentile & <95th percentile) or obese (BMI≥95th percentile).
Results: :
Of 461 subjects, 54.5% were male and 85.3% were white. Median age at first eye clinic visit was 10.8 (Q1, Q3: 8.3, 13.7) yrs and DM duration 3.4 (1.7, 6.1) yrs. The group was 67% (309) under/normal weight, 22% (103) overweight and 11% (49) obese. Over a median follow-up of 3.5 (1.4, 6.1) yrs and 3 (2, 5) eye examations, 9% (42) of 460 subjects with no baseline DR developed mild or moderate nonproliferative DR in at least one eye. No patients developed more severe DR. There was a significant relationship between worse DR outcome and higher initial BMI percentile; DR developed in 15% of obese, 9% of overweight, and 6% of under/normal weight children (p=0.01). Faster progression to DR was associated with higher initial BMI percentile (HR: 1.08, p=0.04). Development of DR was associated with longer DM duration (4.9 vs 3.3 yrs, p=0.02), longer follow-up (5.9 vs 3.2 yrs, p<0.0001) and higher average HbA1c (9.3 vs 8.4%, p<0.0001), total cholesterol (180.3 vs 165 mg/dL, p=0.002) and systolic BP (115.0 vs 109.7 mmHg, p<0.0001). Multivariable analysis confirmed that patients who were overweight or obese throughout follow-up were significantly more likely to develop DR than leaner counterparts even after controlling for age, follow-up duration and HbA1c (p=0.02).
Conclusions: :
In pediatric patients with type 1 DM from a tertiary referral center specializing in DM care, being overweight or obese was associated with faster progression to DR. Given the increasing prevalence of obesity and DM in the pediatric population, these data highlight the potential importance of early weight control in association with glycemic control to reduce DR complications in young patients with type 1 DM.
Keywords: diabetic retinopathy • diabetes