Diagnostic value of signs and symptoms associated with peripheral arterial occlusive disease seen in general practice: A multivariable approach

Objectives. To assess the diagnostic values of single and combined data from the history, physical examination, and medical record with regard to peripheral arterial occlusive disease (PAOD) in patients with leg complaints; to construct a multivariable model for the clinical diagnosis of PAOD by primary care physicians. Setting. 18 general practice centers in The Netherlands. Design. Cross-sectional comparison of signs, symptoms, and data from the medical record with the independently assessed ankle-brachial systolic pressure index (ABPI; cutoff point < 0.90); analysis: bivariate, multiple logistic regression (MLR). Population. 2,455 individuals with leg complaints, aged 40.7-78.4 years; ABPI < 0.90 present in 9.2% of legs (11.7% of individuals). Outcome measures. Clinical variables: sensitivity, specificity, positive and negative predictive values (PV+, PV-), diagnostic odds ratio (OR); models: likelihood ratio test, area under the receiver operating characteristic curve (AUG). Results. Bivariate analysis: highest sensitivity: age more than 60 years (77.3%); highest specificity: wounds or sores on toes and foot (99.7%); highest PV+: typical intermittent claudication (IC) (45.0%) (abnormal foot pulses 41.3%); highest PV-: strong pulses of both foot arteries (97.7%). MLR: the best-performing model (AUG 0.89) consisted of ten clinical variables: gender (OR 1.5), age more than 60 (OR 2.2); IC (OR 3.5); palpation of the skin temperature of the feet (OR 2.5), palpation of both foot pulses [OR 16.4 (abnormal) and 7.0 (doubtful)], auscultation of the femoral artery (OR 3.5); previous diagnosis of IHD (OR 1.7) or diabetes (OR 1.6), history of smoking (OR 2.1), and elevated blood pressure (OR 1.5). The range of predicted probabilities was 0.4-98%. The Hosmer-Lerneshow goodness-of-fit test indicated good overall fit (p = 0.52). Conclusions. Palpation of both foot pulses is the key procedure for the clinical diagnosis of PAOD. Traditional clinical evaluation enables the general practitioner to exclude the diagnosis of PAOD in many individuals with a high degree of certainty, to establish the diagnosis in a small group of patients, and to define a limited group of patients where supplementary noninvasive testing is appropriate. The MLR model can be used as a diagnostic checklist and as a reference for the physician's clinical hypothesis.