Aims: There is conflicting evidence to support the concept that the years with diabetes preceding puberty may not contribute to the development of vascular complications. In this paper, duration-related prevalence of retinopathy was compared in patients who developed type 1 diabetes before and after pubertal age.
Methods: Retrospective analysis of prospectively collected data of 1,483 patients was screened for retinopathy in 1991-2010, with diabetes onset at age ≤29, who were on insulin treatment and aged ≤60. Prepubertal age was defined as 0-12 in males and 0-11 in females.
Results: A total of 647 patients had developed diabetes before and 836 after puberty. Cumulative prevalence of retinopathy was initially lower among those with prepubertal onset diabetes but rates became superimposable after 20-year duration. Patients with prepubertal onset diabetes had higher lifetime HbA1c and lower blood pressure than those who became diabetic after puberty.
Conclusions/interpretation: Retinopathy is infrequent during childhood and develops later than in patients with post-pubertal onset diabetes. After 20-year duration, however, retinopathy becomes just as prevalent suggesting that, in the long term, prepubertal years do contribute to the development of retinopathy. In this series, higher blood pressure may have played a role in the earlier appearance of retinopathy in patients with diabetes onset after puberty, whereas worse metabolic control may have contributed to the late "catch-up" effect in those with prepubertal onset disease.