Vasodilator response to galvanic current stimulation of the skin accurately detects acetylsalicylic acid intake: A study in 400 vascular patients.
BACKGROUND AND AIMS
The first cause of low-dose acetylsalicylic-acid (ASA) inefficacy is poor adherence to treatment. No non-invasive technique is available to assess ASA intake. Current-induced vasodilation (CIV) was found abolished in healthy volunteers after low-dose ASA intake. We tested clinical characteristics, treatments, and comorbid conditions influencing CIV amplitude in vascular patients.


METHODS
CIV was tested in 400 patients (277 males and 123 females, aged 65.4 ± 13.4 years). We focused on clinical characteristics, treatments, and comorbid conditions as covariates of CIV amplitude. We studied the CIV amplitude to covariate relationships with multivariate linear regression and receiver operating characteristics (ROC).


RESULTS
The multivariate linear model determined that ASA intake within the last 48 h and the interaction between ASA intake and body mass index (BMI) were the sole covariates associated with CIV amplitude. For the whole population, the area under the ROC curve (AUC) for CIV to predict ASA intake was 0.853 [95% confidence interval (CI): 0.814-0.892]. Considering separately the areas observed for non-obese (BMI ≤30, n = 303) and obese (BMI>30, n = 93) patients, the AUC [95% CI] was 0.873 [0.832-0.915] and 0.776 [0.675-0.878], respectively (p = 0.083).


CONCLUSIONS
ASA is the only drug that affects the amplitude of CIV response observed after galvanic current application to the skin of vascular patients. CIV depends on BMI but not age or gender. As such, CIV appears to be a potential objective marker of ASA intake and could facilitate future non-invasive assessments of adherence to ASA treatment.
['Florczak|Anne-Sophie|AS|', 'Henni|Samir|S|', 'Signolet|Isabelle|I|', 'Hamel|Jean-François|JF|', 'Humeau-Heurtier|Anne|A|', 'Rousseau|Pascal|P|', 'Abraham|Pierre|P|']
D000368:Aged D001241:Aspirin D015992:Body Mass Index D002317:Cardiovascular Agents D016903:Drug Monitoring D005260:Female D005712:Galvanic Skin Response D006801:Humans D008297:Male D055118:Medication Adherence D008875:Middle Aged D019338:Polypharmacy D011237:Predictive Value of Tests D012867:Skin D004561:Transcutaneous Electric Nerve Stimulation D014652:Vascular Diseases D014664:Vasodilation
Laser speckle contrast imaging Microcirculation Peripheral vascular disease