Results from a retrospective cohort study show that young people with type 2 diabetes were almost twice as likely to develop retinopathy compared to those with type 1 diabetes.
To prevent serious eye complications, children with type 2 diabetes (T2D) may need ophthalmoscopic evaluations at least as often as, or more often than, children with type 1 diabetes (T1D), according to the results of a retrospective, population-based review. The findings were published in JAMA Ophthalmology.
Specifically, the analysis of 525 subjects under the age of 22 found “diabetic retinopathy, proliferative diabetic retinopathy (PDR), and the need for pars plana vitrectomy (PPV) occurred within a shorter diabetes duration for children with T2D compared to T1D,” the authors explained, while “children with T2D had almost twice the risk of developing retinopathy compared to children with T1D.”
Diabetic retinopathy, the leading cause of blindness in young adults, is caused by neurodegeneration of the retina and a breakdown of the blood-retinal barrier. While the ocular sequalae of T1D and T2D have been well studied, less is known about the progression of diabetic retinopathy in children with T2D, despite the increasing prevalence of the disease, the researchers said.
In addition, there are limited data on the treatment of diabetic retinopathy in patients with childhood-onset T2D. To address this knowledge gap, the researchers assessed the risk of developing diabetes-associated ocular complications (DAOC) over 50 years.
All individuals with T1D or T2D diagnosed between January 1, 1970 and December 31, 2019, living in Olmsted County, Minnesota (95.7% Caucasian in 1990), were included in the retrospective assessment of the map. Using data from the Rochester Epidemiology Project, the researchers used diagnostic codes to determine diagnoses and subsequent ocular diabetes complications.
Of the 606 children who received their diagnosis in this window, 86.6% underwent at least 1 eye exam after their diabetes diagnosis (n = 461 with T1D; n = 64 with T2D), while “follow-up eye exams were recorded for any change in the status of retinopathy through age 40,” the authors wrote.
Patients with T1D were followed for a mean (SD) of 13.6 (9.4) years, and those with T2D 8.6 (6.9) years. The mean age at diagnosis was 12.1 (5.4) years and a small majority of patients (50.3%) were male. Overall, DAOC occurred in 31.2% of children with T1D and in 26.6% of children with T2D.
However, analyzes revealed the following HR for the specific risk of ocular complications between T2D and T1D frequencies, respectively:
1.88 (95% CI, 1.13-3.12; P = 0.02) for developing diabetic retinopathy (non-proliferative or greater) 2.33 (95% CI, 0.99-5 .50; P = 0.048) for PDR 1.49 (95% CI, 0.46 -4.89; P = 0.50) for diabetic macular edema 2.43 (95% CI, 0.54-11, 07; P = 0.24) for a visually significant cataract4.06 (95% CI, 1.34-12.33; P = .007) for those requiring PPV within 15 years of diabetes diagnosis
Approximately 83% of the T1D cohort was Caucasian, compared to 55% of the T2D cohort. The T2D cohort also included a higher percentage of Asian and Black youth compared to the T1D cohort; these differences are consistent with previous research showing that childhood-onset T2D is more common in American, Asian, black, and Hispanic youth than in white youth. T1D is more common in white youth.
According to the researchers, their findings suggest that “the natural history of retinopathy development in adolescents diagnosed with T2D may differ from that in adolescents diagnosed with T1D, where patients with T2D may be more prone to developing retinopathy than those with T1D despite diabetes control. maturity.”
Due to the retrospective nature of the study, incomplete data and irregular follow-up may highlight limitations, while changes in diabetes diagnosis and management over the past 50 years may have affected comparisons across decades.
The predominantly white population of Olmsted County also limits the generalizability of the findings to more racially diverse populations. “Because racial and ethnic minorities have experienced higher rates of diabetes and retinopathy in other studies, in a more racially diverse population, the rate of diabetes and DAOC may be higher than what was observed in this population-based cohort,” the authors explained.
In an accompanying editorial, Jennifer K. Sun, MD, MPH, an associate professor of ophthalmology at Harvard Medical School, emphasized the need to better understand the outcomes of diabetic retinopathy in young people, as the number of young people with T1D is expected to nearly triple. and those with T2D will nearly quadruple by 2050.
Despite improvements in medical care and patient education observed in the United States in recent years, “the increased global incidence of diabetes implies that there will be a growing number of individuals at risk of vision loss due to diabetic retinopathy over the following decades,” Sun wrote.
Given the limitations of the study among Minnesota residents, Sun also emphasized his valuable contribution to the field. “Accurate risk estimates for the occurrence of sight-threatening complications such as PDR and diabetic macular edema are crucial in establishing appropriate screening guidelines for baseline and follow-up retinal exams,” she said.
The report confirms the very low risk of developing advanced retinopathy before puberty and underlines the need to clarify any differences in ocular outcomes between adolescents with T1D and adolescents with T2D.
Further epidemiological studies in different cohorts are needed to help optimize baseline screening guidelines in the modern era, Sun concluded. “Such efforts could potentially lead to a better understanding of the mechanistic differences between pathology in T1D versus T2D and ideally provide insight into therapeutic targets to preserve vision in youth with diabetes in the subsequent decades of hyperglycemia.”