PO0073 - Validation of DOAC Dipstick in obese patients anticoagulated with direct oral anticoagulants. Rationale and study design

Background: In obese patients the drug distribution and plasma concentrations of direct anticoagulants (DOAC) may be unpaired, potentially exposing the patients to a greater risk of both thrombotic and hemorrhagic events. DOAC Dipstick in urine samples of anticoagulated normal weight patients showed a high accuracy at plasma threshold concentrations of 30 ng/ml, suggesting a possible future role in DOAC clinical management. However, no study has been performed to investigate the validity of this rapid test in anticoagulated obese patients.

Aims: The primary end point of this study is to evaluate the accuracy of DOAC Dipstick in detecting therapeutical plasma concentration of of DOACs in obese anticoagulated patients. A further sub-analysis will be performed to evaluate the accuracy of DOAC Dipstick in patients with mild, moderate, and severe obesity.

Methods: This is the protocol description for for a cross sectional single center study in obese patients treated with DOACs.

Results: According to the WHO classification, obesity is defined as: mild if body mass index (BMI) is comprised between 30 and 35, moderate if BMI is between 35 and 40, severe if BMI is higher than 40. The DOAC Dipstick contains two separate specific pads for testing DXI and DTI. DOAC Dipstick results will be compared visually with the reference scale. Plasma DOAC concentration will be assessed by Liquid Chromatography-Mass Spectrometry. Dipstick test results for DXI or DTI will be compared with plasma concentration at a threshold of 30 ng/ml to analyze the true positive and true negative rate.

Conclusion(s): This is the protocol for the first study aimed to investigate the role of DOAC Dipstick in detecting therapeutic DOAC concentration in obese patients. The demonstration of a good accuracy of DOAC Dipstick in obese populations could ameliorate body weight adjusted DOAC management in clinical routine to accelerate medical decision making and for assure adherence to therapy.