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

NCT07363187 | Not Yet Recruiting

• 1 other identifier: SBU-IEAH-EC274
• Study Type: observational
• Target: 90
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Endothelial Dysfunction; Occupational Radiation Exposure; Microvascular Dysfunction

Keywords

Nailfold capillaroscopy; Microvascular changes; Low-dose ionizing radiation; Occupational radiation exposure; Healthcare workers; Endothelial dysfunction; Inflammation biomarkers; D-dimer; High-sensitivity C-reactive protein; Asymmetric dimethylarginine

Outcome Measures

Primary Outcomes (1)

• Microvascular Changes Assessed by Nailfold Capillaroscopy

  Microvascular alterations will be evaluated using nailfold capillaroscopy, including capillary density and morphological abnormalities such as tortuosity, dilatation, elongated capillaries, dystrophic changes, avascular areas, microhemorrhages, neoangiogenesis, and subpapillary plexus visibility. Capillaroscopic findings will be assessed using standardized semi-quantitative scoring criteria

  Baseline (single assessment at study visit

Secondary Outcomes (6)

• Serum Asymmetric Dimethylarginine (ADMA) Level

  Baseline (single assessment at study visit)

• Serum von Willebrand Factor (vWF) Level

  Baseline (single assessment at study visit)

• Serum High-Sensitivity C-Reactive Protein (hs-CRP) Level

  Baseline (single assessment at study visit)

• Serum D-dimer Level

  Baseline (single assessment at study visit)

• Correlation Between Nailfold Capillaroscopy Scores and Serum Biomarker Levels

  Baseline (cross-sectional analysis)

Study Arms (2)

Radiation-Exposed Healthcare Workers

Healthcare workers with chronic occupational exposure to low-dose ionizing radiation as part of their routine professional activities in medical departments where radiation is used.

Non-Exposed Control Group

Healthcare workers without occupational exposure to ionizing radiation, working in departments where radiation-based procedures are not used.

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

The study population will consist of healthcare workers aged 18 to 60 years employed at a tertiary care hospital. The exposed group will include healthcare workers with chronic occupational exposure to low-dose ionizing radiation, while the control group will include healthcare workers without occupational radiation exposure, working in non-radiation-related departments within the same institution. Participants will be recruited on a voluntary basis and will undergo a single study visit including nailfold capillaroscopy, blood sample collection, and completion of demographic and occupational exposure questionnaires.

You may qualify if:

• Healthcare workers aged between 18 and 60 years.
• For the control group: Employment in a healthcare institution with either occupational exposure to low-dose ionizing radiation or no occupational radiation exposure.
• For the exposed group: chronic occupational exposure to ionizing radiation for at least 3 years.
• Willingness and ability to provide written informed consent.
• Ability to comply with study procedures, including nailfold capillaroscopy and blood sample collection.

You may not qualify if:

• History of cardiovascular disease, cerebrovascular disease, or peripheral vascular disease.
• Presence of systemic diseases that may affect microvascular structure or endothelial function, including diabetes mellitus, uncontrolled hypertension, dyslipidemia, or chronic kidney disease.
• Known autoimmune, connective tissue, or systemic inflammatory diseases (e.g., systemic sclerosis, lupus erythematosus, vasculitis).
• Active infection or acute inflammatory condition at the time of enrollment.
• Use of systemic medications that may affect endothelial function or microcirculation within the past 4 weeks, including vasodilators, antihypertensive agents, statins, antiplatelet or anticoagulant drugs.
• Current smoking or history of smoking within the past 6 months.
• Pregnancy or breastfeeding.
• History of malignancy or current cancer treatment.
• Previous finger trauma, surgery, or local conditions affecting the nailfold area that may interfere with capillaroscopic evaluation.

Sponsors & Collaborators

• Istanbul Training and Research Hospital: lead

Study Sites (1)

Istanbul Training and Research Hospital

Istanbul, 34000, Turkey (Türkiye)

Location

Biospecimen

Retention: SAMPLES WITHOUT DNA

Venous blood samples will be collected from all participants. Serum samples will be obtained after centrifugation. Von Willebrand factor (vWF) and D-dimer levels will be measured using routine hospital biochemistry laboratory methods. Serum samples for the measurement of asymmetric dimethylarginine (ADMA) and high-sensitivity C-reactive protein (hs-CRP) will be aliquoted and stored at -80°C until analysis by ELISA methods. No DNA extraction or genetic analyses will be performed, and all samples will be used exclusively for the purposes defined in this study.

Study Officials

• Elif Banu Yildiran, MD

  Istanbul Training and Research Hospital, Dept. of Dermatology

  PRINCIPAL INVESTIGATOR

• Duygu Yamen, MD

  Istanbul Training and Research Hospital, Dept. of Dermatology

  STUDY DIRECTOR

• Ayse Esra Koku Aksu, MD, Prof

  Istanbul Training and Research Hospital, Dept. of Dermatology

  STUDY CHAIR

Central Study Contacts

Elif Banu Yildiran, MD

CONTACT

+905303552144; elifbanuyildiran@gmail.com

Duygu Yamen, MD

CONTACT

+905064016136; dyerdil@gmail.com

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Target Duration: 1 Day
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Dermatology Resident Physician

Study Record Dates

• First Submitted: January 7, 2026
• First Posted: January 23, 2026
• Study Start: February 1, 2026
• Primary Completion: April 1, 2026
• Study Completion: May 1, 2026
• Last Updated: January 26, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will share

Locations

TU (1)