Role of nursing in the assessment of Peripheral Artery Disease: Comparison of two ankle to arm Index methods in patients with Diabetes

• IWGDF ABI calculation (D2) doubles detection of abnormal ABI values (18.8% vs 9.0%). • Compared with D1, D2 identifies a slightly younger patient population. • D1 and D2 classifications differ by sex, smoking status, cholesterol and glomerular filtration. • Clinical signs of PAD show low sensitivity and limited diagnostic utility alone. • Routine ABI screening is essential, even in asymptomatic individuals with diabetes. To compare the clinical implications of the new International Working Group on the Diabetic Foot (IWGDF) criterion for calculating the ankle-brachial index (ABI), which uses the lowest systolic blood pressure (SBP) in the foot (Diagnosis 2, D2), versus the classical method that uses the highest SBP (Diagnosis 1, D1). Additionally, we assessed patient characteristics and the diagnostic accuracy of clinical signs of peripheral artery disease (PAD). A cross-sectional study analyzed 442 limbs from 221 patients with diabetes. ABI was calculated as the foot SBP (highest for D1, lowest for D2) over the highest arm SBP. Low ABI (≤ 0.90) was considered indicative of PAD. Clinical and sociodemographic variables were collected. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for PAD signs. The prevalence of low ABI was 9.0% using D1 and 18.8% using D2, representing an absolute increase of 9.8 percentage points, with all D1 cases also identified by D2. Compared with D1, patients identified using D2 were slightly younger (66.28 ± 8.91 vs. 67.48 ± 11.27 years; p = 0.024), had a lower proportion of men (72.1% vs. 77.5%; p = 0.042), differed in smoking status distribution (p = 0.016), showed lower total cholesterol levels (153 ± 27.23 vs. 164.08 ± 36.96 mg/dL; p = 0.040), and had reduced glomerular filtration rate (58.57 ± 8.14 vs. 62.47 ± 10.47 mL/min/1.73 m²; p = 0.009). Clinical signs and symptoms demonstrated limited sensitivity but generally high specificity for PAD detection, particularly the absence of pedal pulses. The ABI calculation method recommended by the IWGDF doubles PAD detection and identifies a broader and slightly younger at-risk population compared with the traditional method. Given the limited sensitivity of clinical signs alone, these findings support the use of the IWGDF ABI calculation as a systematic screening tool in individuals with diabetes, including those without overt symptoms.