Background: Diabetes is a systemic disease affecting many organs, including skin. Skin may reflect the condition of internal organs. The aim of our study was to measure skin pH in type 1 diabetes mellitus (T1DM) patients and in healthy controls and to evaluate the association between metabolic control of diabetes and skin acidity in T1DM patients.
Materials and methods: The study was conducted on 105 patients with T1DM and 53 age- and sex-matched healthy people. Skin surface pH was measured in three different areas of the body (cheek, forearm, and foot) in diabetes patients and healthy controls. The results were compared for patients' and controls' clinical characteristics and for patients' metabolic control and also evaluated according to the presence of complications of diabetes.
Results: Patients with T1DM had lower skin pH compared with the control group in three measured areas: within the cheek (5.49 ± 0.42 vs. 5.69 ± 0.31; P = 0.001), forearm (5.41 ± 0.46 vs. 5.73 ± 0.69; P = 0.004), and foot (5.20 ± 0.53 vs. 5.41 ± 0.41; P = 0.008). In the multiple linear regression skin pH was negatively correlated with fasting plasma glucose on the cheek (β = -0.34, P = 0.0004), forearm (β = -0.30, P = 0.0009), and foot (β = -0.18, P = 0.04). Diabetes patients with glycated hemoglobin (HbA1c) ≥ 8% had significantly lower skin pH than patients with better glycemic control (HbA1c < 8%). However, we observed a statistically significant difference only on the foot (5.09 ± 0.50 vs. 5.34 ± 0.55; P = 0.019).
Conclusions: Skin surface pH is lower in individuals with diabetes, and it is negatively related to actual and chronic hyperglycemia.