Glycaemic control and its relation to foot skin pH in people living with type 2 diabetes mellitus

Abstract

Aim: To determine any differences in foot skin pH values in people living with type 2 diabetes presenting with different glycaemic control levels within the Maltese population, when compared to healthy individuals. Research Design and Method: A quantitative comparative observational study was conducted on a population of Maltese patients living with type 2 diabetes and a group of healthy patients, as controls. Two hundred and forty-one participants (n=241) were recruited for this study, 180 living with type 2 diabetes mellitus and 61 healthy participants. The participants living with type 2 diabetes were categorised into 3 different groups according to their HbA1c levels. A 20 minutes acclimatisation period was given to each participant before skin pH testing commenced. Demographic information such as age, gender, weight, height, diabetes duration, medications, BMI, daily physical activity and alcohol intake were recorded prior to testing. Once the acclimatisation period was over, skin pH at predefined sites (plantar, interdigital and dorsal areas of each foot) was measured utilizing the Skin pH meter (Apera PH60F). Participants required to attend for only a single session. The researcher followed a predefined protocol when taking skin pH readings for each participant. The Shapiro-Wilk test was used to determine the normality of data. The Kruskal Wallis test was employed to determine if a significant difference was found between groups, while other statistical tests such as the Shapiro-Wilk, Spearman correlation, Mann Whitney and Chi-square tests were used to analyse and compare other variables in relation to foot skin pH. Results: The study found a significant difference (p < 0.05) between mean skin pH at the 3 regions of interest (ROI) and the 4 groups of participants recruited in the study. Group 2 (good HbA1c) presented with the lowest foot skin pH in all ROI, followed by group 1 (healthy), group 3 (fair HbA1c) and with group 4 (poor HbA1c) having the highest skin pH values. The mean interdigital foot skin pH was always higher (less acidic in nature), when compared to the other sites for both the left and right foot across all groups. The higher the HbA1c score, the higher (less acidic) the mean foot skin pH was observed in all ROI. Conclusions: The results of this study demonstrated significant differences between the four groups and concluded that the more controlled blood glucose levels, the less foot skin pH tends to fluctuate from the normal acidic values. With the aid of this study health policies should start considering testing for skin pH especially in the foot region to enable health professionals to pinpoint disturbances in the skin acid mantle which can result in frequent skin infections and conditions affecting immunocompromised patients such as those with uncontrolled diabetes.