Time in range in relation to amputation and all‐cause mortality in hospitalized patients with diabetic foot ulcers

SLR - June 2022 - Stephanie Behme PGY 2

Reference: Xie P, Deng B, Zhang X, Li Y, Du C, Rui S, Deng W, Boey J, Armstrong DG, Ma Y, Deng W. Time in range in relation to amputation and all-cause mortality in hospitalised patients with diabetic foot ulcers. Diabetes Metab Res Rev. 2022. Feb;38(2):e3498.

Level of Evidence: IV

Scientific Literature Review

Reviewed By: Stephanie Behme PGY 2
Residency Program: McLaren Oakland Hospital (Pontiac, MI)

Podiatric Relevance: This study looked at factors beyond HbA1c at preventing the risk of ulcerations and ampu-tations in the diabetic patient. As it is well known that HbA1c is a calculation of how well blood glucose levels are controlled over the past three months, this study looked at blood glucose levels seven times a day and investigated if there was correlation between staying within range of “normal” levels and the risk of amputations, ulcerations, and mortality of the diabetic patient. This is relevant to the podiatric field, as this could be used to educate patients that while HbA1c is a good assessment tool, having good time-in-range (TIR) blood glucose levels is a better predic-tor of outcomes following ulcers and amputations.

Methods: All diabetic patients admitted to the hospital had comorbidities, previous amputations, risks and de-mographics recorded. These individuals were subjected to seven blood glucose draws per day and were then strati-fied into levels based on TIR, time-above-range or time-below-range. Statistical analysis was performed to compare baseline characteristics among in-patients with their clinical outcomes. 

Results: The study found that patients with a lower limb amputation had higher levels of inflammatory markers including white blood cells, C-reactive protein and a higher grade on the Wagner scale for their foot ulcerations. In addition to this finding, patients with a lower limb amputation were also found to have less TIR with their blood glucose level, an elevated HbA1c and lower levels of serum sodium. Blood glucose levels with more TIR were found to be inversely proportional with amputation rates. 

Conclusions: While HbA1c was previously thought to be the gold standard for assessing glycemic control, this study may have revealed this is not always the case. Going forth, this study can be used to educate diabetic patients a little more that daily glycemic control is the utmost important factor to reducing their risk for ulceration, amputa-tion, and complications from diabetes. In addition to preventing amputations, it would be a great factor to consider while healing from an amputation whether this be while these patients are in- or out-patient.