Benefits of early PAD/LEAD diagnosis

Peripheral artery disease (PAD) might not be immediately fatal or significantly affect quality of life, but it can quickly progress into a grave medical issue if it is not diagnosed and managed in a timely manner. Early diagnosis has many advantages, from better long-term quality of life to reduced mortality and decreased costs of treatment.

Cardiovascular diseases (CVDs), of which PAD is also a part, are the leading cause of mortality worldwide and in 2016 alone accounted for more than 17.9 million deaths (31% of all deaths globally), about 85% of which were due to heart attack and stroke [1].

How many of those are due to PAD is difficult to estimate, let alone calculate, at least on a global level, as this insidious disease often goes undiagnosed despite being comorbid to many lethal CVDs, like stroke and coronary artery disease (CAD).

For example, PAD is quite common in those with CAD with prevalence between 22 and 42%; patients with both diseases fare worse (in terms of quality of life and mortality) than those with only CAD [2,3,4,5]. Association with the biggest killer amongst the CVDs is just one of the reasons for preventive screening for PAD – indicative connection with general cardiovascular health being the other and most important one.

Does screening for PAD lead to reduced morbidity and mortality from PAD?

The asymptomatic nature of PAD makes timely and accurate diagnosis only on the basis of a physical examination a tall order and misdiagnosis is common, especially if performed by a less experienced examiner [6]. Fortunately, there are more advanced diagnostic methods and tools with high accuracy and specificity, specifically the ABI (ankle-brachial index) measurement, which lends itself to screening of large numbers of potential patients [7]. However, for the screening processes to be cost-effective, clinicians should first identify at-risk individuals on the basis of well-established risk factors for PAD.

The most prominent risk factor for PAD (and atherosclerosis in general) is tobacco smoking; it dramatically increases the incidence of PAD in men, while female smokers are even worse affected as they are at a 20-fold increased risk (over a 13-year period) in comparison with non-smokers [8,9].

Another one is diabetes since the most common symptom of PAD (intermittent claudication) and one that greatly affects the patient’s quality of life (diminished physical activity) is 3.5 times more prevalent in male diabetics and 8.6 times more in female diabetics than in the non-diabetic populations [10]. Lastly, hyperlipidaemia, hypertension and weight (obesity) round the list of risk factors with emphasis on obesity, which contributes to a 3 to 5-fold increase in incidence of PAD [11,12,13].

Preventive screening of patients for PAD (on the basis of the ABI measurement) has the benefit of improving the accuracy of cardiovascular risk prediction beyond the FRS (Framingham risk score) and can, indirectly, predict the risk of total and cardiovascular mortality [14].

Even more, timely identification of PAD has a positive effect on morbidity. One study showed that early identification of PAD on the basis of ABI and the presence of intermittent claudication and subsequent lifestyle change intervention significantly improved the frequency and time of physical activity (important part of conservative management of PAD due to its antiatherogenic effect) and even contributed to smoking cessation in some patients who participated in the study [15]. A study conducted in Germany and encompassing elderly individuals demonstrated the improvement of cardiovascular risk factors after 2 years of treatment after an initial diagnosis of PAD on the basis of ABI measurement [16].

In short, screening for PAD on the basis of ABI has many benefits, with special consideration for individuals in at-risk groups for PAD.