OBJECTIVES: Impacts on health-related quality of life are reported across cardiovascular diseases (CVD), including physical function limitations (PFLs). Antithrombotic therapy is indicated to treat/prevent thromboembolic conditions. Content-valid patient-reported outcome assessments in antithrombic treatment studies are needed. This qualitative study evaluated the content relevance of standard physical function assessment tools in patients with self-reported prior stroke (PS), acute coronary syndrome (ACS), or atrial fibrillation (AF) who use antithrombotic therapies to understand the patient perspective on PFLs and attributions to their antithrombotic therapy.

METHODS: Interviews were conducted among patients in the US, UK, Germany, and Japan who were recruited using existing databases, social networks, and clinician referral networks. Individual 90-minute interviews were conducted via video conference with trained qualitative research interviewers. Three standardized scales assessing physical function were discussed during interviews: PROMIS-29 (5-item physical activities subscale), PROMIS (3 physical function items), and PROMIS-10 (single global daily activities item).

RESULTS: Of 64 patients using antithrombotic therapies, the average age was 60.5 years, and 52% were female. Fifty-five (86%) patients reported doing the physical activities in the questionnaires, 37/55 (71%) had difficulty. Thirteen (20%) patients attributed their PFLs to their antithrombotic therapy. No differences were seen between the PS, ACS, or AF patient groups. While 4 participants preferred the PROMIS-10 global item, most supported the 5-item PROMIS-29 subscale or the 3 physical function PROMIS items. Key reasons for supporting the latter 2 measures focused on clarity and specificity.

CONCLUSIONS: PFLs are relevant to patients with PS, ACS, or AF on current antithrombotic therapy. Over half of the participants reported difficulty with the activities listed in the questionnaires, supporting the relevance of PROMIS physical function assessment. Only 20% attributed their PFLs to their antithrombotic treatment, suggesting caution in the interpretation of change in physical function when evaluating antithrombotic treatment-related benefit.