Digital thermography and vascular involvement in β-thalassemia intermedia

Beta-thalassemia intermedia (β-TI) is associated with vascular dysfunction. We used digital thermal monitoring (DTM), a non-invasive tool that evaluates vascular function based on changes in fingertip temperature during and after cuff occlusion on β-TI patients. Thirty-three patients (18 years and older) were recruited in this study and divided into 3 groups: thalassemia, anemic controls, and healthy controls. Exclusion criteria included factors that are known to be associated with vascular damage. Patients underwent DTM and results were extracted as vascular reactivity index (VRI), a measure of how well the circulatory system responds to stimuli that require adjustments of blood flow. One-way analysis of variance (ANOVA) was used to test the mean difference in VRI between the 3 groups. A multiple linear regression was also carried out with VRI as the outcome of interest and a function of covariates that were thought to be of clinical relevance to VRI. The frequency, mean VRI ± standard error (SE) for the thalassemic group were (N = 16), mean = 2.243 ± 0.111; for anemic controls (N = 9), mean = 2.374 ± 0.162; and for the controls (N = 8), mean = 2.338 ± 0.092. ANOVA test indicated a non-significant difference in mean VRI between the three groups (P value = 0.731). Multiple linear regression couldn't detect any significant association between VRI and any of the predictors including the groups. Our study did not show a significant difference in VRI between the 3 study groups. Prospective studies of larger sample size are warranted to establish DTM as a possible non-invasive tool used to evaluate vascular function in β-TI patients.