Only Ankle-Brachial Index May Not Be an Accurate Information About the Prevalence of Peripheral Arterial Disease

We read the article ‘‘Peripheral arterial disease is prevalent but underdiagnosed and undertreated in the primary care setting in central Greece’’ by Argyriou et al with interest. They investigated the prevalence of peripheral arterial disease (PAD) and assessed in physician and patient the awareness of the disease as well as the risk factors associated with PAD and the level of its treatment. They demonstrated that the prevalence of PAD, especially asymptomatic PAD, is prominent among participants aged 50 to 70 years. The ankle-brachial index (ABI) is a valuable diagnostic tool for PAD. Measurement of ABI in patients with subclinical PAD allows the timely initiation of preventive measures as well as the recognition of vascular disease in other arterial beds. Previous studies demonstrated that an abnormal ABI is not only a marker of PAD but also a predictor of generalized atherosclerosis. For this reason, the results might be different, if the authors had mentioned cardiovascular risk factors in their study. The early diagnosis of PAD and the initiation of conservative measures are related not only to a reduction in disease progression but also to numerous additional beneficial actions. Aggressive vascular risk factor modification in patients with PAD is associated with a reduction in the risk of vascular events as well as decreased disease progression. Furthermore, some medications such as antihypertensive treatment, aspirin, and statins may influence the ABI parameters. A low ABI has been demonstrated as a marker of decreased renal function over time in a general population of patients, and the presence of concomitant renal dysfunction in patients with PAD is associated with higher morbidity and mortality rates as well as the occurrence of cardiovascular events. It would be useful if the authors provide data about these risk factors and their possible relationship with the ABI. Finally, measurement of ABI manually by Doppler is a well-known method to diagnose PAD. In a previous study, measuring the photoplethysmography and continuous-wave Doppler ultrasound in addition to ABI measurement in patients with a probable PAD was suggested in suspected patients as the ABI has a sensitivity of 69.3% and a specificity of 99.6%, and in this regard it may miss a real diagnosis of PAD. But in real life, the measurement of ABI and the practice of these additional tools may consume more time and lead to higher costs. This may decrease the effectiveness of these methods. Further studies will be needed to reveal the clinical relevance of these additional investigations. Besides the ABI, several other markers or tests such as C-reactive protein, functional photoplethysmography, and using a noninvasive automated device may reflect the presence of PAD. We believe that these findings will provide useful information about the ABI measurements and diagnosis of PAD.