THE DIAGNOSTIC-VALUE OF THE MEASUREMENT OF THE ANKLE BRACHIAL SYSTOLIC PRESSURE INDEX IN PRIMARY HEALTH-CARE

We investigated the value of the ankle-brachial systolic pressure inde x (ABPI) as a test for the diagnosis of peripheral arterial occlusive disease (PAOD) in general practice. ABPI measurements on 231 legs of 1 17 subjects performed in three general practice centers (GPC) were com pared with the diagnostic conclusions of a Vascular Laboratory. The op timum cutoff value for the ABPI, its accuracy and diagnostic value wer e estimated. In a subpopulation of 51 subjects for whom repeated measu rements were available, we checked whether taking the mean of three co nsecutive ABPIs for test outcome would enhance diagnostic performance. Receiver Operating Characteristic analysis showed that overall perfor mance of the GPC ABPI was good (area under the curve approximate to 0. 9). Performing repeated ABPI measurements was superior to performing a single measurement. The optimum cutoff value for the ABPI was 0.97, a ssociated with a diagnostic odds ratio (OR) of 17 and an accuracy of 8 1%. In a somewhat more selected subpopulation, the optimum cutoff valu e was 0.92 (OR 70, accuracy 90%). On the basis of our results, we sugg est the following rule of thumb: if the ABPI < 0.8 or if the mean of t hree ABPIs < 0.9, it is highly probable that PAOD is present (PV+ grea ter than or equal to 95%); if the ABPI > 1.1 or if the mean of three A BPIs > 1.0, PAOD can be ruled out (PV- greater than or equal to 99%). In conclusion, in primary health care, the ABPI measurement can be a u seful supplementary test in ambiguous diagnostic situations with regar d to PAOD. Copyright (C) 1996 Elsevier Science Inc.