Long-Acting Insulin Analogs: Effects on Diabetic Retinopathy

Long-acting insulin analogs are designed to enhance glycemic control without excessively lowering blood glucose. But structural modifications of the insulin molecule can alter biological responses and binding characteristics with specific receptors; in short, they can potentially raise the risk of sight-threatening diabetic retinopathy (STDR), say researchers from Taipei City Hospital and National Taiwan University, both in Taiwan.

The researchers note that some clinical trials have reported that intensification of endogenous insulin might accelerate progression of pre-existing STDR. However, they add that some studies used cancer cell lines, and insulin was administered at supraphysiologic concentrations.

The researchers conducted a retrospective study to evaluate the effects of long-acting insulin analogs (glargine and/or detemir) with neutral protamine Hagedorn (NPH) insulin on the progression of STDR in 46,739 patients with type 2 diabetesmellitus (T2DM).

They found no changed risk of STDR with the long-acting insulin analogs, between either matched or unmatched cohorts. For instance, with a median follow-up of 483 days, they found 479 events with glargine initiators in 8,947 patients. There were 541 events in a median of 541 days’ follow-up for 8,947 patients in the NPH initiators group. The detemir group, with 411 days of follow-up, had 64 events.

Despite a “relatively short” observation period, the researchers say their findings agree with those of a previous open-label randomized study of patients with T2DM, which found treatment with insulin glargine over 5 years did not increase progression of STDR, compared with NPH insulin treatment.

Source
Lin JC, Shau WY, Lai MS. Clin Ther. 2014;36(9):1255-1268.
doi: 10.1016/j.clinthera.2014.06.031.3.