USA: A recent study in the journal Diabetes Care showed that early intensive glycemic control reduces the long-term risk of diabetic foot ulcers (DFUs) -- the most important antecedent in the causal pathway to lower-extremity amputation (LEAs).
Previous studies have demonstrated that intensive glycemic control reduces the risk of retinal, kidney, and eurologic complications in type 1 diabetes (T1D). However, it is not known if it reduces the risk of lower-extremity complications.
Considering the above, Edward J. Boyko, Veterans Affairs Puget Sound Health Care System, Seattle, WA, and colleagues aimed to examine whether former intensive versus conventional glycemic control reduced the long-term risk of diabetic foot ulcers (DFUs) and lower-extremity amputations (LEAs) among Diabetes Control and Complications Trial (DCCT) participants in the subsequent Epidemiology of Diabetes Interventions and Complications (EDIC) study.
For this purpose, DCCT participants (n = 1,441) were made to complete 6.5 years on average of intensive versus conventional diabetes treatment. Following this, 1,408 were enrolled in EDIC and followed annually over 23 years for DFU and LEA occurrences by physical examination. The researchers also estimated associations of DCCT treatment assignment and time-updated exposures with DFU or LEA using multivariable Cox proportional hazard regression models.
Following were the study's salient findings:
Intensive versus conventional glycemic control was associated with a significant risk reduction for all DFUs (hazard ratio 0.77) and a similar magnitude but nonsignificant risk reduction for first-recorded DFUs (0.78) and first LEAs (0.70).
In adjusted Cox models, clinical neuropathy, lower sural nerve conduction velocity, and cardiovascular autonomic neuropathy were associated with higher DFU risk; estimated glomerular filtration rate <60 mL/min/1.73 m2, albuminuria, and macular edema with higher LEA risk; and any retinopathy and greater time-weighted mean DCCT/EDIC HbA1c with higher risk of both outcomes.
"Our results showed that a period of intensive glycemic control early in the course of T1D reduced DFU risk during subsequent long-term follow-up in the DCCT/EDIC cohort," wrote the authors. "To our knowledge, this is the first demonstration of a reduction in DFU risk associated with a randomized intervention to improve glycemic control."
Reference:
Edward J. Boyko, Leila R. Zelnick, Barbara H. Braffett, Rodica Pop-Busui, Catherine C. Cowie, Gayle M. Lorenzi, Rose Gubitosi-Klug, Bernard Zinman, Ian H. de Boer; for the DCCT/EDIC Research Group, Risk of Foot Ulcer and Lower-Extremity Amputation Among Participants in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Study. Diabetes Care 1 February 2022; 45 (2): 357–364. https://doi.org/10.2337/dc21-1816