Optical coherence tomography and histological assessment of cutaneous vasculature and neural changes in long-term smokers: an exploratory study.

Smoking affects microcirculation by damaging endothelial cells and reducing blood flow. Vascular disease is also thought to contribute to the development of diabetic neuropathy, resulting in the decrease of nerve fiber density. The impact of nicotine on vasculature using optical coherence tomography angiography (OCT-A) has been extensively studied. We utilized an alternative method, reactive hyperemia OCT-A (RH-OCT-A), to provide a more complete visualization of microvasculature changes in the forearm of 5 old female smokers (mean age = 62.6yrs) and 7 young female smokers (mean age = 26.6yrs) compared against old (n = 17, mean age = 67.8yrs) and young (n = 22, mean age = 24.0yrs) nonsmoking populations. Intraepidermal nerve fiber densities (IENF) were collected from 6 old female smokers (mean age = 63.0yrs) and 12 young female smokers (mean age = 26.3yrs) and compared against 11 old female nonsmokers (mean age = 66.2yrs) and 13 young female nonsmokers (mean age = 24.2yrs). A trend was observed from vessel density measurements showing old smokers with the lowest value (15.7%), followed by old nonsmokers (16.4%), young smokers (18.8%), and finally young nonsmokers (18.9%). Additionally, the correlation within the smoking population between pack-year history and vessel density was stronger than the correlation between subject age and vessel density (R= -0.53 vs. R= -0.42). Using RH-OCT-A, we show that smoking history is associated with lower vessel density and therefore suggestive of accelerated aging.