Is Skin Auto Fluorescence related to Peripheral Arterial Occlusive Disease?

Background and aims: Peripheral arterial occlusive disease (PAOD) has enormous consequences for the patient and for society. It can reduce the quality of life of elderly drastically and is strongly associated with an elevation of cardiovascular and overall mortality. Despite the serious impact of the disease, the diagnosis is often missed. In the best scenario, patients are diagnosed shortly after the start of symptoms. We want to determine whether skin auto fluorescence (SAF) is elevated in those affected and whether SAF correlates with the severity of disease. We hope to find support for a new way for early assessment in PAOD. Materials and methods: In this prospective case control study, we have measured SAF with the AGE-reader in patients with PAOD. The patients were randomly recruited from the outpatient department of Vascular surgery of the University Hospital in Groningen. A total of 135 patients with PAOD were included as well as a control group of 135 healthy age and gender matched individuals. Results: SAF is significantly higher in patients (M=1,06 SD=0,24) compared with controls (M=0,87 SD=0,25) (P<0,001) even after correction for the possible confounder smoking. A one-way ANOVA for the SAF of the different ABI groups (<0.5, 0.5-0.9, 0.9-1.4, >1.4 or incompressible arteries) was significant, F (3,174) = 3,870, p = 0.010, even after correction for confounders. SAF was higher in the group with elevated ABI compared to the other groups. SAF was also elevated in patients with PAOD with a decreased Ankle Brachial Index (ABI) (M=2,99 SD=0,73) compared to those who regained a normal ABI (M=2,55 SD 0,45) (P=0,040). The difference in SAF for different groups within the maximum experienced Fontaine classification were not significant, F (5,129) = 0,806, p = 0,548 just like for the current Fontaine: F (5,128) = 1,115, p = 0,356. Conclusions: SAF is elevated in PAOD patients compared to healthy controls. This elevation is irrespective of the severity of PAOD or of the level of occlusion of PAOD but does seem to reflect the presence of a decreased or elevated ABI.