Factors influencing primary care physicians' prescribing behavior of anticoagulant therapy for the management of patients with non-valvular atrial fibrillation in Singapore: a qualitative research study.

BACKGROUND: Oral anticoagulant therapy use in patients with atrial fibrillation (AF) remains suboptimal in Singapore, despite the availability of both warfarin and non-vitamin K antagonist oral anticoagulants (NOACs). Primary care physicians' (PCP) decision-making to initiate and select appropriate anticoagulant medication is pivotal in reducing complications among patients with AF. This study explored the factors influencing PCPs' decision-making in anticoagulant initiation and anticoagulant switch for patients with non-valvular AF. METHOD: The study design is qualitative research based on the theoretical framework of the Generalist Wheel of Knowledge, Understanding and Inquiry. In-depth interviews or focus group discussions were conducted with 27 PCPs in general practice in urban Singapore. The audio-recordings were transcribed and coded to identify themes, which are framed according to the "clinician", "patient", "medical condition and treatment" and "healthcare system and policy" domains. RESULTS: Personal training and experience with anticoagulant therapy; understanding patient risk-stratification; AF detection during clinical practice; medication cost; clinical support services for anticoagulation monitoring and constraints in existing care model influenced PCPs in their anticoagulant prescription. PCPs preferred to seek guidance from cardiologists in managing patients with newly diagnosed AF and attempted to engage their patients in decision-making regarding anticoagulant therapy. Some PCPs perceived sub-specialized primary care clinics focusing on AF co-management with cardiologists as an ideal setting for initiation and maintenance of anticoagulant therapy. CONCLUSIONS: PCPs are influenced by multiple interrelated factors while making decisions on anticoagulant initiation and anticoagulant switch for patients with AF. Their proposed care model to address the barriers awaits feasibility and acceptance assessment in future research.

A novel dextran-oleate-cRGDfK conjugate for self-assembly of nanodrug.

We report a novel synthetic biocompatible material: a conjugate with a fatty acid-substituted dextran decorated with cRGDfK peptide, which was used as a stable coating material instead of the conventional poly(ethylene glycol) for nanodrug preparation. This novel dextran-oleate-cRGDfK conjugate (DO-cRGDfk) could self-assemble into a micellar structure in aqueous solution, and was used as a surfactant to formulate nanodrug with poly(d,l-lactic-co-glycolic) acid as matrix to encapsulate paclitaxel with high drug-loading efficiency. The conjugate allowed the fabrication of nanodrug with a targeting moiety on its surface in a simple and robust step. The resultant nanoparticles could induce cellular apoptosis more effectively than that of the commercial paclitaxel formulation, Taxol. Thus, DO-cRGDfk could be used as an alternative to poly(ethylene glycol) as a biocompatible surface coating polymeric material for nanoparticle preparation. FROM THE CLINICAL EDITOR: The authors describe a novel synthetic biocompatible conjugate, which consists of a fatty acid-substituted dextran decorated with cRGDfK peptide. This conjugate was used as a stable coating material for nanodrug preparation, and can be used in place of conventional PEG.