The association between tobacco smoking and systolic toe pressures in active foot ulceration

Smoking may increase the risk of diabetic foot disease and ulceration. It does so by impairing glycaemic control and promoting the formation of advanced glycated end-products. Additionally, smoking is known to delay surgical wound healing and accelerate peripheral arterial disease. We aimed to determine whether toe pressures differed in smokers with a foot ulcer, when compared to non-smokers and ex-smokers, as well as ulcer outcomes at 12 months, among patients attending Blacktown Hospital High Risk Foot Service (HRFS). This study is a retrospective analysis of our prospectively collected clinic database. Eligible participants were adults attending the HRFS between June 2020 and April 2022. Participants were included if they had an ulcer, at least one systolic toe pressure reading completed at their initial visit and attended at least one follow-up visit. Participants were followed until healing, loss to follow-up or a minimum of 12 months. A total of 195 participants were included; 36 smokers, 82 ex-smokers, and 77 controls who had never smoked. Smoking status was by self-report. Current smokers were significantly younger at initial presentation (p = .002) and tended towards lower socioeconomic status (p = .067). Current smokers were significantly more likely to have ischaemic grade 3 toe pressures (< 30 mmHg) of their left foot (p = .027), suggestive of reduced perfusion. At the end of follow up period, smokers had the numerically highest rates of minor amputations. In conclusion, smokers ulcerate younger and are more likely to have grade 3 ischaemia. Collecting information about the brachial artery pressures and the time since the last cigarette may clarify any relationship between smoking and toe pressures.Trial registration: WSLHD HREC ethics approval 2111-02 and ANZCTR registration 382470. Registered on 15/09/2021.