Transcutaneous oxygen pressure (TcPO2): A novel diagnostic tool for peripheral neuropathy in type 2 diabetes patients

Aims

The assessment of transcutaneous oxygen pressure (TcPO₂) may serve as a non-invasive and lower-cost alternative to nerve conduction studies (NCSs) for the diagnosis of diabetic peripheral neuropathy (DPN). The aim of this study was to determine whether the measurement of TcPO₂ is useful for evaluating DPN.

Methods

We performed a cross-sectional study of 381 consecutive hospitalized diabetic patients classified by clinical examination and NCS as having DPN. Anthropometric and metabolic parameters were assessed. The TcPO₂ examination was performed in both supine and sitting positions.

Results

Three hundred and one patients had DPN. The TcPO₂ in both the supine and sitting positions was highest in the Non-DPN group and lower in the confirmed DPN group than the other three groups (p < 0.001). The Non-DPN group had the lowest sitting-supine position difference in TcPO₂ among the groups (p < 0.001). The risk factors strongly associated with DPN included sitting-supine position difference in TcPO₂ (OR = 4.971, p < 0.001), diabetic retinopathy (DR) (odds ratio [OR] = 3.794, p = 0.002), and HbA1c (OR = 1.534, p = 0.033). The area under the curve (AUC) of the sitting-supine position difference in TcPO₂ was 0.722 and revealed an optimal cut-off point for the identification of DPN (19.5 mmHg) that had a sensitivity of 0.611 and a specificity of 0.738 based on AUC analysis.

Conclusions

This large study of diabetic patients confirms that the sitting-supine position difference in TcPO₂ is higher in DPN patients than control subjects, indicating that TcPO₂ examination is a promising valuable diagnostic tool for DPN.