Introduction: Engaging patients in medical decision-making is important, especially for conditions such as peripheral arterial disease (PAD) that have multiple treatment options. Lack of information or support in decision-making can create uncertainty about benefits and risks, and impact decisional quality. Significant work is needed to document decisional quality in PAD populations.
Methods: In PORTRAIT, a multi-center study of patients with new or worsening of PAD symptoms in the US, the Netherlands, and Australia, patients were interviewed about their PAD-specific health status (PAQ - Peripheral Artery Questionnaire) and clinical variables were abstracted from medical records. The initial treatment strategy and patient-reported decisional conflict, captured using the 4-item SURE instrument, were assessed at 3 months. Patients experience conflict when they lack knowledge on treatments, treatment risks and benefits, and in the absence of support during or after the treatment decision. Variation in decisional conflict by site was assessed using median odds ratios (MOR). The association of decisional conflict with treatment strategy (invasive vs. non-invasive) and 1-year PAQ summary scores was assessed using multivariable regression models adjusted for site and baseline health status.
Results: 21% of patients reported decisional conflict. The MOR for site variability was 2.01 (95% CI 1.56-3.13; p<0.01), but 1.12 (95% CI 1.00-1.46; p=0.35) after adjusting for country. Greater decisional conflict was associated with a lower odds of invasive treatment (OR=0.58; 95% CI 0.34;1.00; p=0.05) and a smaller 1-year PAD health status change (adjusted B=-4.72; 95% CI -9.38;-0.06; p=0.05), even adjusting for PAD treatment strategy.
Conclusion: While there is variation for the occurrence of decisional conflict, stratifying results by country showed non-US sites had more conflict. Patients with decisional conflict were more likely undergo non-invasive treatment first and had an almost 5-point smaller change in health status, even after adjusting for PAD treatment. Increasing knowledge and support for non-invasive treatment options should reduce measured decisional conflict and may ensure the treatment can be effective for patients with PAD.