Older age and longer duration of type 1 diabetes also play a role in the development of diabetic retinopathy, according to a chart review.
A chart review showed that diabetic retinopathy (DR) is associated with older age, longer duration of type 1 diabetes, earlier onset of type 1 diabetes, and some modifiable risk factors.
The results, according to first author Konstantina Sampani, MD, indicated that maintaining control of blood pressure (BP) and hemoglobin A1c (HbA1c) are key to preventing the onset of DR. Sampani, who is from the Joslin Diabetes Center Beetham Eye Institute, Boston, presented the findings of her group at the Association for Research in Vision and Ophthalmology annual meeting in Seattle.
The investigators conducted a retrospective chart review of patients’ demographic and clinical data from 2005 to 2020.
The investigators used spectral-domain optical coherence tomography (SD-OCT) macular scans for a subset of patients and automated retinal layer segmentation to determine the inner and outer layers (IRL, ORL). The researchers sought correlations between the patient demographics, body mass index (BMI), blood pressure (BP), HbA1c, and retinal layer cell thickness and volume with the presence of DR, Sampani recounted.
The demographic data from the cohort were as follows. A total of 1,359 patients (2,704 eyes; 49.6% female; mean age, 13.7±4.3 years) were included. The mean duration of the type 1 diabetes was 7.0±5.2 years, the mean age at onset of type 1 diabetes, 7.7±4.7 years; mean HbA1c, 8.4±1.3%; mean BMI, 21.9±4.3; mean systolic BP, 109.2±10.4; and mean diastolic BP, 65.8±7.4.
Of the 2,704 eyes, 139 (5.14%) had DR, of which 5.1% was nonproliferative and 0.04% was proliferative.
The following significant correlations were found with the presence of DR: older age (p<0.001), longer duration of type 1 diabetes (p<0.001), earlier onset of type 1 diabetes (p<0.04), higher HbA1c (p<0.001), and high systolic and diastolic BP (each p<0.001). They also pointed out that these correlations remained significant after adjusting for age, gender, HbA1c, duration of type 1 diabetes, and the age at onset of type 1 diabetes.
A subset of 109 eyes (69 patients) who had SD-OCT images and no DR had higher HbA1c values that were associated significantly with thinner central subfield thickness (p = 0.001) and thinner IRL (p=0.004). Higher systolic BP also was correlated significantly with increased IRL volume (p=0.02). No significant relationships were identified between the total IRL or ORL thickness and the BMI, diastolic BP, or duration of type 1 diabetes.
The study underscored the significant associations seen with older age, longer disease duration, earlier disease onset, and some modifiable risk factors, and the importance of controlling BP and HbA1c to prevent disease onset.
In addition, the correlation between higher HbA1c and thinner IRL in eyes without DR may mean that neurodegeneration is associated with worse glycemic and BP control. The authors emphasized that their results highlight the importance of controlling modifiable risk factors to prevent DR and potentially reduce subclinical neural retinal loss in young patients with type 1 diabetes.