Continuous subcutaneous insulin infusion therapy is associated with reduced retinopathy progression compared with multiple daily injections of insulin

Abstract

Aims/hypothesis We aimed to compare diabetic retinopathy outcomes in people with type 1 diabetes following introduction of continuous subcutaneous insulin infusion (CSII) therapy with outcomes in people receiving continuing therapy with multiple daily insulin injections (MDI). Methods This is a retrospective cohort study using the Scottish Care Information – Diabetes database for retinal screening outcomes and HbA1c changes in 204 adults commenced on CSII therapy between 2013 and 2016, and 211 adults eligible for CSII during the same period but who continued on MDI therapy. Diabetic retinopathy progression (time to minimum one-grade worsening in diabetic retinopathy from baseline grading) was plotted for CSII and MDI cohorts using Kaplan–Meier curves, and outcomes were compared using multivariate Cox regression analysis adjusting for age, sex, baseline HbA1c, blood pressure, cholesterol, smoking status and socioeconomic quintile. Impact of baseline HbA1c and change in HbA1c on diabetic retinopathy progression was assessed within CSII and MDI cohorts. Results CSII participants were significantly younger, were from less socially deprived areas, and had lower HbA1c and higher diastolic BP at baseline. There was a larger reduction in HbA1c at 1 year in those on CSII vs MDI (−6 mmol/mol [−0.6%] vs −2 mmol/mol [−0.2%], p < 0.01). Diabetic retinopathy progression occurred in a smaller proportion of adults following commencement of CSII vs continued MDI therapy over mean 2.3 year follow-up (26.5% vs 18.6%, p = 0.0097). High baseline HbA1c (75 mmol/mol [9%]) was associated with diabetic retinopathy progression in the MDI group (p = 0.0049) but not the CSII group (p = 0.93). Change in HbA1c at follow-up, irrespective of baseline glycaemic status, did not significantly affect diabetic retinopathy progression in either group. Conclusions/interpretation CSII was associated with reduced diabetic retinopathy progression compared with continued MDI therapy, and may be protective against diabetic retinopathy progression for those with high baseline HbA1c. Progression of diabetic retinopathy over 3 years was not associated with a change in HbA1c. Graphical abstract

Effects of intensive insulin therapy on the retinal microvasculature in patients with type 2 diabetes mellitus: a prospective observational study

“…High-dose insulin might be one of the reasons for the transient worsening of diabetic retinopathy during intensive insulin treatment [ 42 ]. In the report by Reid et al [ 43 ], CSII was associated with reduced diabetic retinopathy progression compared with continued MDI therapy, and maybe protect against diabetic retinopathy progression for those with high baseline HbA1c. Further studies are needed to explore the relationship between insulin doses and retinal vessel density.…”

Volkskrankheit diabetische Retinopathie

“…Schwankungen sind im Zeitalter der kontinuierlichen Glukosemessung gut über die sog. "Time in Range" (Zeit, die der Blutzucker innerhalb definierter Zielgrenzen liegt) zu fassen und moderne Closed-Loop-Insulinpumpen scheinen die Inzidenz der DR entsprechend senken zu können [34] Besonders spannend ist, dass bei lipidsenkenden Therapien mit Fibraten, insbesondere mit Fenofibrat, neben den indirekten Effekten über die Lipidsenkung ein zusätzlicher eigener "intrinsischer" positiver Effekt des Präparates auf den Verlauf einer DR erkannt wurde [37]. Dieser Effekt wird gerade in einer DRCR-Net-Studie (Protocol AF, NCT04661358) weiter untersucht und im Falle des erwarteten positiven Studienausganges würde dann mit der Fibrattherapie erstmals ein orales Präparat aus ophthalmologischer Indikation zur Sekundärprophylaxe gegen DR-Progression eingesetzt werden können [38].…”

Continuous Glucose Monitor, Insulin Pump, and Automated Insulin Delivery Therapies for Type 1 Diabetes: An Update on Potential for Cardiovascular Benefits

“…Yet, few existing studies have assessed for relationships between technology use and complication onset or severity in T1D. Limited studies suggest that CSII use may reduce microvascular complications seen in T1D, such as retinopathy, neuropathy, and diabetic kidney disease [116][117][118][119][120][121][122][123]. There is also evidence suggesting insulin pump use may be beneficial for cardiovascular risk factors and CVD.…”