Physical examination to screen for peripheral artery disease in a defined Primary Care population: A diagnostic accuracy study.

INTRODUCTION: Peripheral arterial disease (PAD) is an underdiagnosed prevalent disease which implies high cardiovascular risk. Professionals usually depend on physical examination to screen for PAD. OBJECTIVE: To assess the diagnostic accuracy of physical examination to screen for PAD in a rural Primary Care population and to evaluate the nurse-physician level of agreement in pedal pulse palpation. METHODS: Diagnostic accuracy study in which two experienced professionals (physician-nurse) prospectively performed pedal pulse palpation (grading as absent, reduced, normal, or bounding), femoral bruit auscultation and calf circumference (index tests) comparing with Doppler ABI (reference test, positive cut-off: 0.9 ≥ ABI ≥ 1.4) in 158 consecutive subjects. INCLUSION CRITERIA: presence of diabetes, dyslipidaemia, hypertension, smoking habit (current or former), or age ≥ 65. RESULTS: Of 315 legs included, PAD was confirmed in 38 (12.1%) legs. Absent dorsalis pedis (DP) and posterior tibial (PT) pulses were found in 37 (11.7%) and 67 (21.3%) legs, respectively. Regarding nurse evaluation, when a positive test was set if DP or PT were absent (more sensitive cut-off), sensitivity was = 86.8 (95% CI: 74.8-98.9), specificity = 82.7 (95% CI: 78.0-87.3), likelihood ratio+ = 5.01 (95% CI: 3.77-6.67), likelihood ratio- = 0.16 (95% CI: 0.07-0.36), and diagnostic odds ratio (dOR) = 31.5 (95% CI: 11.7-84.8). Age, diabetes, and calcification (ABI ≥ 1.4) influenced the rate of a false negative finding in pedal palpation. Physician-nurse weighted kappa coefficient was = 0.649 (95% CI: 0.599-0.699). The presence of a femoral bruit auscultation had a dOR = 3.8 (95% CI: 1.1-13.1), and a calf circumference <34.55 cm had a dOR = 3.2 (95% CI: 1.6-6.4). CONCLUSIONS AND RELEVANCE: In a mainly asymptomatic Primary Care population, pedal pulse palpation was by far the best diagnostic test, with good diagnostic accuracy and inter-rater agreement. In view of a high sensitivity and capacity to rule out the disease, pedal pulse palpation could be performed as a screening test for PAD and individuals at high cardiovascular risk.

Simultaneous inter-arm and inter-leg systolic blood pressure differences to diagnose peripheral artery disease: a diagnostic accuracy study.

PURPOSE: Inter-arm systolic blood pressure differences (IASBPD) and inter-leg systolic blood pressure differences (ILSBPD) have arisen as potential tools to detect peripheral artery disease (PAD) and individuals at high cardiovascular risk. This study aims to evaluate the diagnostic accuracy of IASBPD and ILSBPD to detect PAD, and whether IASBPD or ILSBPD improves diagnostic accuracy of the oscillometric ankle-brachial index (ABI). MATERIALS AND METHODS: In this prospective study, eligible for inclusion were consecutive adults, with at least one of the following cardiovascular risk factors: diabetes, dyslipidemia, hypertension, smoking habit or age ≥65. IASBPD, ILSBPD and ankle-brachial index (ABI) were measured in all participants through four-limb simultaneous oscillometric measurements and compared with Doppler ABI (reference test, positive cut-off: ≤ 0.9). RESULTS: Of 171 subjects included, PAD was confirmed in 23 and excluded in 148. Thirteen and 38 subjects had IASBPD and ILSBPD ≥10 mmHg, respectively. Pearson correlation with Doppler ABI of IASBPD and ILSBPD was 0.073 (P = .343) and -0.628 (P < .001), respectively. Diagnostic accuracy of an ILSBPD ≥10 mmHg to detect PAD was: sensitivity = 69.6% (95%CI = 48.6-90.5), specificity = 85.1% (79.1-91.2), diagnostic odds ratio (dOR) = 13.1 (4.8-35.5) and area under ROC curve (AUC) = 0.765 (0.616-0.915). IASBPD had an AUC = 0.532 (0.394-0.669), and oscillometric ABI had an AUC = 0.977 (0.950-1.000). The addition of ILSBPD to oscillometric ABI reduced dOR from 174.0 (38.3-789.9) to 34.4 (9.5-125.1). Similarly, the addition of IASBPD reduced dOR to 49.3 (14.6-167.0). CONCLUSIONS: In a Primary Care population with ≥1 cardiovascular risk factors, ILSBPD showed acceptable diagnostic accuracy for PAD, whilst IASBPD accuracy was negligible. However, the combination of ILSBPD (or IASBPD) with oscillometric ABI did not improve the ability to detect PAD. Thus, oscillometer ABI seems to be preferable to detect PAD and individuals at high cardiovascular risk. ILSBPD could be uniquely recommended for the diagnosis of PAD when blood pressure measurements in upper limbs are not possible.