Characterization of Baseline Temperature Characteristics Using Thermography in The Clinical Setting

Background: Thermography is a diagnostic method based on the ability to record infrared radiation emitted by the skin and is unique in its ability to accurately show physiological and/or pathological cutaneous temperature changes in a non-invasive way. This method can be used to indirectly assess changes or impairments in cutaneous perfusion. Significant technological advancements have allowed thermography to be more commonly utilized by clinicians, yet a basic consensus of patient characteristics that may affect temperature recordings is not established. Materials and Methods: We evaluated cutaneous temperature in a cohort of outpatients to understand what factors, including tobacco use and other high-risk characteristics, contribute to cutaneous tissue perfusion as measured by thermography. Participants were prospectively enrolled if they were a combustible cigarette smoker, an electronic cigarette (e-cigarette) user, or a never smoker. Standardized thermographic images of the subject's facial profiles, forearms, and calves were taken and demographic characteristics, medical comorbidities, and tobacco product use were assessed. These variables were statistically tested for associations with temperature at each anatomic site. Results: We found that gender had a significant effect on thermographic temperature that differed by anatomic site, and we found a lack of significant difference in thermographic temperature by race. Our regression analysis did not support significant differences in thermographic temperatures across smoking groups, while there was a trend for decreased perfusion in smokers relative to non-smokers and e-cigarette users relative to non-smokers. Conclusion: Thermographic imaging is a useful tool for clinical and research use with consideration of sex and other perfusion-affecting characteristics.