Ischaemic outcomes assessment survey: A pilot study in patients with peripheral arterial disease

Abstract

Background

Patients with peripheral arterial disease (PAD) are at increased risk for stroke, myocardial infarction (MI) and cardiovascular death. Prior studies have focused on the prevalence of PAD, but the rate of ischaemic outcomes among a diverse group of patients with PAD has received less attention. In addition, the assessment of ischaemic outcomes with the use of a survey in place of casenote review, to our knowledge, has not been defined. The purpose of this pilot study was to develop an ischaemic outcomes survey that could be used in place of the labour-intensive casenote review, for data collection as part of a large epidemiological study.

Methods

A data abstraction form was used as a guide in blinded casenote reviews to compare the patient's reported medical history to casenote documented ischaemic events. The proportion agreement and Cohen's kappa were used to measure the agreement and the statistical significance of this agreement between the questionnaire and casenote review items. Fifty-one patients with a history of PAD were consented and interviewed using a 23-item questionnaire that focused on the ischaemic events of unstable angina, MI, cerebral vascular accident, transient ischaemic attacks, lower extremity revascularisation, or lower extremity amputation.

Results

Of the 23 patient survey items, proportion agreement was ≥ 70% on more than half of the items with kappa statistics that were fair-to-moderate. For ischaemic outcomes such as lower extremity bypass surgery, there were no yes responses from the patient or within the medical record, which reflects the low prevalence of this outcome.

Conclusions

Overall, the ischaemic outcomes questionnaire was a valid research tool. It yielded statistically significant kappa values on several items. Although additional work is needed, the present survey provides a good framework on which to develop the final questionnaire, which will be used in a large prospective cohort study to capture ischaemic events in patients with PAD.