Cardiovascular diseases (CVDs) are quite insidious types of medical conditions as they rarely exhibit symptoms until they are already in a more advanced stage. Peripheral arterial disease (PAD) is no exception and can be difficult to accurately diagnose without the proper diagnostic tools, even if the patient exhibits symptoms that could be attributed to the disease.
However, such patients are a minority since far more of them are entirely asymptomatic or have symptoms that could be ascribed to other medical conditions: studies have shown that only 10% of individuals have typical PAD symptoms, while the former (asymptomatic group) represent 40% of all cases and the latter the remaining half [1, 2].
The most typical symptom is, of course, intermittent claudication, which can be mistaken for sciatica, delaying proper and timely treatment. Misdiagnosis is also common amongst diabetic patients as pain and discomfort associated with intermittent claudication can be masked by diabetic neuropathy.
Speaking of diabetes and intermittent claudication: studies have shown that this typical symptom is 3.5 times more common in male and 8.6 more common in female diabetics than in non-diabetics (of respective genders) .
Diabetes as such is one of the two biggest risk factors (the other one is tobacco smoking) for PAD – these are facts every physician who has patients with PAD (and possible other important comorbid medical conditions) should know (in addition to other known risk factors). Still, general practitioners worldwide are dealing with an increasing reduction of time allocated per patient per visit; coupled with the need to diagnose or treat more pressing medical issues, that can result in missing many but the most tell-tale signs of PAD.
What is needed are modern, easy-to-use diagnostic tools (like the MESI ABPI MD) and/or at least a helpful list of steps, recommendations and questions – a comprehensive yet brief questionnaire general physicians can use when suspecting possible PAD (inclusion in risk groups, typical symptoms or just general preventive screening).
What should a doctor ask every patient?
Timely and proper treatment of PAD is, of course, reliant on accurate diagnosis of the disease and its severity, whether with the use of modern diagnostic tools or through a classical physical examination, supplemented with a comprehensive questionnaire (for the patient). The best of those listed options would, of course, be diagnosing using modern tools (devices), followed by both physical examination (sans procedures involving diagnostic tools) and a questionnaire in the second place.
However, modern diagnostic methods might be either unavailable or the mere suspicion (in the absence of other evidence) of possible PAD doesn’t warrant their use (from a cost perspective), while the accuracy of physical examination is dependent on the physician’s skills and experience (4). In such cases a questionnaire might be the only tool at the physician’s disposal for assessing the relative risk of PAD – final diagnosis should still be made through the use of other diagnostic methods (ABI, TBI, angiography etc.).
The presented list of 18 questions was prepared on the basis of generally recognised risk factors for PAD and symptomatology, and includes both patient-centric and physician-centric questions. Those that only a patient knows (physical sensations in his body, other symptoms), but hasn’t yet conveyed to his personal physician, and those that have answers in the patient’s medical record on the physician’s desk or computer (or are otherwise self-evident).
List of questions for assessing the relative risk of PAD:
- AGE. How old is the patient?
- ETHNICITY. Self-evident.
- GENDER. Self-evident.
- TOBACCO SMOKING. Does the patient smoke (current smoker) or did he ever smoke (former smoker)?
- DIABETES. Does the patient have diabetes (type 1 or 2)?
- DIAGNOSED CORONARY ARTERY DISEASE (CAD). Does the patient have CAD?
- HISTORY OF MYOCARDIAL INFARCTION (MI), STROKE OR TRANSIENT ISCHAEMIC ATTACKS (TIA). Has the patient at any time in their life experienced MI, stroke or TIA?
- DIAGNOSIS OF CHRONIC KIDNEY DISEASE (CKD). Has the patient been diagnosed with CKD or renal insufficiency in general?
- DIAGNOSIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). Has the patient been diagnosed with COPD?
- HYPERLIPIDAEMIA. Does the patient suffer from abnormally elevated levels of lipids (lipoproteins)?
- HYPERTENSION. Is the patient hypertensive?
- Weight. Is the patient over- or underweight?
- INTERMITTENT CLAUDICATION. Does the patient report pain during any sort of physical exercise, even walking? Does the pain subside when he/she takes a rest? Where (body part) is the pain located?
- COLD FEET/LEGS. Does the patient report a cold feeling in his leg(s) or feet despite feeling otherwise (in other parts of the body) warm or otherwise comfortable at the current ambient temperature?
- SCALY SKIN/OF PALE OR BLUEISH HUE/DEFORMED TOENAILS. Does the patient report abnormal skin texture and colour and toenail deformation?
- OPEN WOUNDS AND SORES. Does the patient have any types of wounds or other tissue damage on his legs/feet that heals very slowly or doesn’t appear to heal at all?
- ERECTILE DYSFUNCTION (MEN). Does the patient have erectile dysfunction?
- FAMILY HISTORY. Does the patient know whether any of his relatives had or currently have PAD?
Interpretation of answers (in the same numerical order) and additional information:
- Older patients (over 50 years of age) are at an increased risk of PAD, which might be asymptomatic [5, 6].
- There are statistically significant discrepancies in PAD prevalence and morbidity in individuals of different ethnic groups. Studies have shown that black people (specifically African Americans) are at higher risk of developing PAD than white people .
- Some studies have indicated greater prevalence of PAD (particularly more severe forms) in women than in men .
- Current smokers have a far greater risk of developing PAD . Association between tobacco smoking and PAD is especially strong in female smokers, who are at up to 20 times greater risk for the disease than females who have never smoked . Information about past smoking (former smokers) is also important: health benefits of smoking cessation don’t translate well to PAD as even past smokers are at an increased risk with up to 2.6 times greater prevalence of PAD (in comparison with non-smokers) .
- Diabetes-induced hyperglycaemia greatly increases the incidence and prevalence of PAD. Some studies estimate prevalence rates at 20%, but this number is generally recognised as being an underestimation since PAD is frequently entirely asymptomatic or is masked by other symptoms/complications of diabetes .
- Already present (diagnosed) CAD is indicative of possible atherosclerosis in other vascular beds – prevalence rates of PAD in CAD patients range from 22% to 42% [13, 14, 15].
- History of MI and cerebrovascular events is associated with higher prevalence rates of PAD, often in its asymptomatic form (diagnosis on basis of the ABI score) [16, 17, 18].
- Individuals with renal insufficiency are 9 times more likely to have an abnormal (defined as ABI <0.9) ABI score (indication of PAD) .
- Patients with COPD are at double the risk of developing PAD .
- Abnormal levels of blood lipids and lipoproteins is associated with mild risk for development of large-vessel disease .
- Hypertension is a known risk factor for PAD (and other CVDs) .
- Weight is a risk factor for PAD (and many other medical conditions) as studies have shown that older individuals with greater BMI (body mass index) have higher incidence of PAD .
- Accurately diagnosing intermittent claudication on the basis of physical sensations the patient feels during physical exertion and when still/resting is best done using the Edinburgh Claudication Questionnaire .
- Reduced blood flow leads to disruption of normal thermoregulation.
- Occlusion in the arteries of lower extremities reduces flow of nutrients to skin and toenails, leading to stunted growth and deformations. Possible pallor in the affected leg when it is in an elevated position .
- Another tell-tale sign of PAD, but one that is typical for advanced form of the disease are open sores/wounds – arterial insufficiency ulcers (ischaemic ulcers), usually on the patient’s feet. They can be similar to venous ulcers, which have a significantly different underlying pathophysiology and treatment regime, necessitating the use of modern diagnostic methods to differentiate between them (e.g. measuring ABI) .
- Diagnosis of erectile dysfunction carries a twofold increase in the likelihood of PAD .
- Patients with a family history of PAD are at twice the risk of the disease than those without such familial medical history .
In the absence of other diagnostic means, a comprehensive questionnaire is a valuable tool for identifying patients at risk for PAD and any suspicion should be followed by a thorough examination, preferably using modern diagnostic devices.