Nailfold Capillaroscopy and Endothelial Biomarkers in Healthcare Workers Exposed to Chronic Low-Dose Ionizing Radiation

Overview

Chronic occupational exposure to low-dose ionizing radiation may lead to subclinical endothelial dysfunction and early microvascular alterations in healthcare workers. Nailfold capillaroscopy is a non-invasive method that allows direct visualization of microcirculatory changes. This observational study aims to evaluate microvascular alterations using nailfold capillaroscopy and to assess their association with serum endothelial and inflammatory biomarkers, including asymmetric dimethylarginine (ADMA), von Willebrand factor (vWF), high-sensitivity C-reactive protein (hs-CRP), and D-dimer levels. Healthcare workers with chronic low-dose radiation exposure will be compared with non-exposed controls. The study seeks to improve understanding of early vascular effects of occupational radiation exposure.

Chronic occupational exposure to low-dose ionizing radiation may result in subclinical endothelial dysfunction and early microvascular alterations, even in the absence of overt clinical disease. Healthcare workers employed in medical departments where ionizing radiation is routinely used are exposed to cumulative radiation over time. Identifying early vascular changes in this population is important for understanding potential long-term cardiovascular risks associated with occupational radiation exposure. Nailfold capillaroscopy is a non-invasive and reproducible imaging technique that enables direct visualization of the microcirculation and allows detailed assessment of capillary density, morphology, and structural abnormalities. Additionally, circulating endothelial and inflammatory biomarkers such as asymmetric dimethylarginine (ADMA), von Willebrand factor (vWF), high-sensitivity C-reactive protein (hs-CRP), and D-dimer may reflect endothelial dysfunction, inflammation, and prothrombotic activity at a subclinical level. This single-center, observational, cross-sectional study will include healthcare workers with chronic occupational exposure to low-dose ionizing radiation and a control group of healthcare workers without radiation exposure from the same institution. Demographic characteristics, occupational exposure duration, and work-related radiation exposure history will be recorded for all participants. All participants will undergo nailfold capillaroscopy evaluation using standardized assessment criteria, including capillary density, tortuosity, dilatation, dystrophic changes, avascular areas, microhemorrhages, neoangiogenesis, and subpapillary plexus visibility. Venous blood samples will be collected to measure serum ADMA, vWF, hs-CRP, and D-dimer levels using routine laboratory methods and enzyme-linked immunosorbent assay techniques, as appropriate. The primary objective of this study is to identify microvascular changes detected by nailfold capillaroscopy in healthcare workers exposed to chronic low-dose ionizing radiation. Secondary objectives include evaluating the association between capillaroscopic findings, serum biomarkers, and occupational radiation exposure characteristics. The findings of this study may contribute to improved understanding of early vascular effects of chronic occupational radiation exposure and support the use of nailfold capillaroscopy as a practical screening tool in exposed populations.