Automated Ankle-Brachial Pressure Index Measurement by Clinical Staff for Peripheral Arterial Disease Diagnosis in Nondiabetic and Diabetic Patients

Abstract

Response to Clairotte et al. C lairotte et al. (1) recently reported inDiabetes Care that the oscillometric measurement of the ankle-brachial index (Osc-ABI) has lower diagnostic performance in diagnosing peripheral arterial disease (PAD) in diabetic patients when compared with the Dopplermeasured ankle-brachial pressure index (Dop-ABI).Our group has validated the use of an automatic oscillometer (Omron M-7) for Osc-ABI calculation. We chose this model because the sleeve adapts better to the truncated cone morphology of the leg. We used the Doppler Hadeco Bidop (Koven Technology, St. Louis, MO) to measure the sonorous and graphical signal. For the Osc-ABI calculation, three measurements were made and the greatest of these three was chosen as the valid measurement. We studied 228 consecutive patients with arterial hypertension (62.75 Ϯ 12.3 years [mean age Ϯ SD], 51.1% men) of which 69 patients (30.3%) presented with type 2 diabetes.As with the study carried out by Clairotte et al., we achieved good applicability with the Osc-ABI, which was obtainable in 96.2% of the patients. Also in agreement with the results by Clairotte et al., the oscillometer method tended to overestimate the systolic arterial pressure values; hence, the cutoff point to define a pathological ABI would have to be increased from 0.9 to 1.However, in contrast to Clairotte et al., we found a better correlation (Pearson test) between the Osc-ABI and the Dop-ABI both in the total population (r ϭ 0.86) (P Ͻ 0.001) as well as in the diabetic subpopulation (r ϭ 0.88) (P Ͻ 0.001) without significant differences between these groups. The interclass correlation coefficient (inter-observant K) in our population was 0.94 (0.96 in the left leg and 0.94 in the right leg).This discrepancy can be due to the fact that we considered pathological Osc-ABI in those case subjects (17 total case subjects: 8 in the right leg and 9 in the left leg) in which the oscillometer displayed error, unlike Clairotte et al. (1) and other researchers (2-3) who considered these results as invalid.In all these 17 case subjects, the Dop-ABI was Ͻ0.6 and the magnetic resonance angiography confirmed the presence of significant arterial stenosis (Ͼ50%) in the inferior members, supporting the idea that the repeated errors of measurement with the Osc-ABI point to the presence of PAD.It is well known that diabetic patients have greater arterial rigidity (4), which in turn can lead to measurement errors when using the oscillometer method since it is not possible to reach an adequate arterial compression. Therefore, it is probable that Clairotte et al. (1) have underestimated the correlation between the Dop-ABI and the Osc-ABI (5) in their study.In conclusion, we support the use of the oscillometer method for ABI screening equally in both diabetic and nondiabetic populations. The difficulties in obtaining pressure measurements in legs with the oscillometer, especially in diabetic subjects, should not be interpreted as error in the technique but instead as an indication of the presence of ...

Automated determination of the ankle-brachial index using an oscillometric blood pressure monitor: validation vs. Doppler measurement and cardiovascular risk factor profile

“…This finding is in agreement with previous studies reporting that the oscillometric cutoff point to define PAD would have to be increased from 0.90 to B1. 12,20 Furthermore, repeated oscillometric errors were observed more commonly in limbs with PAD. This observation is in line with data reported by Gomez-Huelgas et al 20 and suggests that the inability of the oscillometric method to measure ABI should be interpreted as an indication for the presence of PAD and the need for further imaging (ultrasound, angiography).…”

“…12,20 Furthermore, repeated oscillometric errors were observed more commonly in limbs with PAD. This observation is in line with data reported by Gomez-Huelgas et al 20 and suggests that the inability of the oscillometric method to measure ABI should be interpreted as an indication for the presence of PAD and the need for further imaging (ultrasound, angiography). Indeed, if the inability of the oscillometric method to measure ABI was considered as abnormal ABI, then the agreement between the two methods would be increased (k 0.81).…”

“…[17][18][19] A modest agreement was also recently revealed between the oscillometric and Doppler technique in 146 subjects, with a correlation coefficient of 0.53. 12 However, Beckman et al, 11 validating the oscillometric method in a population of 201 subjects, found a correlation coefficient of 0.78 in both legs, whereas Gomez-Huelgas et al 20 reported a coefficient of 0.86. In other studies, the automated-manual ABI differences averaged B0.03 units.…”

“…The 1.6% failure rate seems to be lower than that recorded by other studies. 12,17,18,20 However, the percentage of erroneous measurements was higher, particularly among limbs with Doppler ABI o0.90 and nonpalpable ankle pulses. It should be noted that the population studied was seen mainly in primary care clinics and not in specialized surgery vascular laboratories, which means that the proportion of subjects with severe PAD was relatively low.…”

Automated oscillometric determination of the ankle-brachial index: a systematic review and meta-analysis

“…Positive and negative study conclusion In 18 of the 25 studies reviewed in this paper (72%; n ¼ 3449), 7,14,[19][20][21][22][23][25][26][27][28]31,[34][35][36]38,40 the authors arrived at a conclusion in favor of oscillometric ABI measurement. Studies with Table 1a Studies that compared the oscillometric with Doppler method for ankle-brachial index measurement a positive conclusion compared with those with a negative one reported a lower but not significant average Doppler-oscillometric ABI difference (0.012±0.010 vs. 0.047±0.035 P ¼ 0.38) and absolute ABI difference (0.044 ± 0.011 vs. 0.060 ± 0.021; P ¼ 0.51), and a significantly higher sensitivity for PAD diagnosis (80 ± 3% vs. 51±5%; Po0.001).…”