The ankle-brachial index (ABI) is a poor indicator of patient-centered and clinician-based evaluations of functional status in patients with intermittent claudication, according to the results of, a prospective observational study of patients with newly diagnosed or an exacerbation of nonlimb-threatening peripheral arterial disease (PAD).
PORTRAIT studied 1,251 patients with intermittent claudication enrolled at 16 sites. Researchers studied the correlation of ABI values and Rutherford symptom classification with PAD-specific health status as measured by the Peripheral Artery Questionnaire (PAQ).
ABI values were categorized as mild (greater than 0.80), moderate (0.40-0.79), and severe (less than 0.40). Spearman rank correlation coefficients were calculated between raw ABI values and PAQ scores and between the Rutherford classification and PAQ scores.
ABI explained only 0.1%-2.1% of the variation in PAQ scores and the Rutherford classification had stronger but still modest associations with PAQ scores, according to the researchers.
“This large study of IC patients found that the PAQ offers a unique and complementary
measure of disease burden that is not captured by physiologic or clinician-observed classifications. The findings from this study highlight the clinical complexity of PAD
and the difficulty in using common hemodynamic and symptom measures to classify the impact of this disease on patients’ health status,” the researchers concluded.
Several authors reported serving as consultant for and/or receiving grants from various device and pharmaceutical companies involved with PAD. The senior author. owns the copyright to the Peripheral Artery Questionnaire that formed the basis for the study.
SOURCE: Johnston A et al. J Vasc Surg. 2018;69(3):906-12.