# Association of Glycated Hemoglobin Levels with Amputation Outcomes in Patients with Diabetic Foot Ulcers: A Cross-Sectional Study in Southern Iran (2023–2024): Effect of HbA1c on Diabetic Foot Ulcer Prognosis

## TL;DR

Higher blood sugar levels over time are linked to more severe amputations in diabetic foot ulcer patients in southern Iran.

## Contribution

This study identifies a significant association between HbA1c levels and the severity of amputation in diabetic foot ulcer patients.

## Key findings

- Elevated HbA1c levels were significantly associated with increased odds of below-knee and foot amputations.
- Patients with less extensive amputations were younger and had shorter hospital stays.
- Lower triglyceride levels were associated with finger amputation.

## Abstract

Diabetic foot ulcer (DFU) is the most serious consequence of type 2 diabetes
mellitus (T2DM), frequently resulting in lower limb amputations. Glycated
hemoglobin (HbA1c) acts as a marker of long-term glycemic control, but its
prognostic value in predicting the severity and level of amputation in DFU
patients remains undefined. This study aims to investigate the association
between HbA1c levels and lower limb amputation risk at various anatomical
levels in patients with DFU.

This cross-sectional analytical study included 446 patients with T2DM and DFU
admitted to Namazi Hospital, Shiraz, Iran, between February 2023 and January
2024. Patients were categorized into four groups based on the amputation
level: above-knee, below-knee, foot/midfoot/forefoot, and toe/finger. HbA1c
was measured and categorized into three groups (7–7.9%, 8–8.9%, and ≥9%).
Univariate and multinomial logistic regression analyses were performed using
the above-knee amputation group as the reference. Statistical analysis was
conducted in R (v4.4.1), with significance set at P0.05.

Elevated HbA1c levels were significantly associated with increased odds of
below-knee and foot amputations compared to above-knee amputation (OR=6.27,
P=0.023 and OR=8.16, P=0.036, respectively, for HbA1c 8–8.9%). Similar
associations were observed for HbA1c ≥9%. Additionally, patients who
underwent less extensive amputations (i.e., foot and finger) tended to be
younger and had shorter hospital stays compared to those who underwent
above-knee amputations. Lower triglyceride levels were also associated with
finger amputation (OR=0.99, P=0.031). These comparisons were made within a
population in which all patients had diabetic foot ulcers.

Higher HbA1c levels are significantly associated with more distal amputation
levels in patients with DFU. Patient characteristics such as younger age,
shorter hospitalization, and lower triglyceride levels were more common
among those undergoing less extensive amputations. These findings highlight
the need for early glycemic control and careful clinical monitoring in DFU
patients at risk of major limb loss.