Gaps in awareness of peripheral arterial disease in Sri Lanka: a cross sectional study

Peripheral arterial disease (PAD) is one of the most common cardiovascular diseases in developed countries [1] and is an emerging problem in developing countries [2, 3]. The Trans-Atlantic Inter-Society Consensus reported the prevalence of PAD in European population studies ranged from 3.6 to 9.2 %, and was 10–20 % in those aged over 70 years [4]. A recent study in Sri Lanka found the age- and sex-standardized prevalence of PAD was 3.6 %, and there was significant increasing trend with age [3]. In the early stages, PAD is mostly silent. With the progression of disease, it may manifest as intermittent claudication, pain at rest, and frank tissue death resulting in lower-extremity amputation [5]. PAD is a major cause of disability, loss of employment, and lifestyle changes, and is a marker for systemic atherosclerotic diseases. The main risk to a patient experiencing claudication is a fatal or non-fatal cardiovascular event [4]. Despite the major health risks associated with PAD, it is generally not recognized by clinicians or the general public in comparison with other cardiovascular diseases. Most individuals with lower extremity PAD are asymptomatic and do not experience recognizable ischemic symptoms until late in the disease progression. However, asymptomatic individuals also have a higher risk of adverse cardiovascular events, similar to those with symptomatic PAD [6].

Low awareness makes addressing the public health impact of PAD challenging [7]. Many studies have shown that public awareness of PAD is much lower than that of other diseases. It has been reported that awareness of PAD ranged from 20 to 36 %, whereas awareness of other common diseases was more than 60 % in the same population [6‐9]. Awareness is important for patients and physicians, and the need for public awareness programs has been highlighted [10, 11]. Thereare no published literature on awareness of diseases in Asian countries.

Although the prevalence of PAD in Sri Lanka is not as high as in Europe or the United States, there is a consistent age-related trend [3]. Anecdotal evidence suggests that a considerable number of patients are detected in the late stage of PAD with severe limb ischemia or chronic non-healing leg ulceration. It is difficult to reduce the morbidity and mortality of untreated PAD without adequate public awareness of PAD and its risk factors and consequences [7]. Insights into public awareness of PAD will help in developing strategies for behavioral change communication and health promotion. In this study we aimed to assess awareness of PAD among adults aged 40–74 years in a district in Sri Lanka.

We recruited 2779 participants from the selected sample of 2912 eligible participants. The response rate was 95.4 %. The proportion of male and female participants was almost equal. The median age of respondents was 52 years (IQR 46–61 years). The awareness of PAD was 4.1 % (95 % confidence interval: 3.4–4.8), which was significantly lower than that of CVA (67.3 %) and MI (57.6 %) (p < 0.001) (Table 1).

The awareness of PAD by participant characteristics is described in Table 2. There were no significant differences in awareness of PAD by age group or level of income (p > 0.05). In addition, there were no significant differences in awareness of PAD among current smokers, those who had intermittent claudication, or those with a history of DM, hypertension, or dyslipidemia (P > 0.05). Multivariate logistic regression analysis showed that being male, an urban resident, and having a higher education level (General Certificate of Education Ordinary Level or above) were independent predictors of high awareness of PAD.

The majority of participants who were “PAD aware” knew that DM (64.0 %) and dyslipidemia (57.9 %) were risk factors for PAD. However, less than one-third of this group was aware that hypertension (31.6 %) and smoking (30.7 %) were risk factors for PAD (Table 3). Walking difficulty and leg amputations were correctly identified as possible consequences of untreated PAD by more than 80 % of the PAD aware group. In contrast, less than 25 % were aware that CVA and MI were possible consequences of PAD (Table 4). In this group, the main sources of information about PAD were physicians (39.5 %) and family members or relatives (37.7 %) and only 10.5 % had received information from mass media such as newspapers, radio, and television (Table 5).

To our knowledge, this is the first study conducted in Sri Lanka to assess public awareness of PAD. In addition, awareness of two common atherosclerotic diseases (MI and CVA) was also assessed and compared with the level of awareness of PAD. Several studies conducted in the United States and Canada compared awareness of PAD with that of common diseases such as DM, hypertension, and dyslipidemia, as well as with some less common diseases such as multiple sclerosis and cystic fibrosis [6, 7].

In Sri Lanka response rate for household survey is generally very high. Potential participants rarely refuse to participate particularly in studies related to health. This was reflected in this study also with the response rate over 95 %. The population proportions in urban and rural divisions in the Gampaha district according to the last census in 2012 was 15.6 % and 84.4 % respectively [15]. Hence, majority in the study population belonged to the rural sector.

Our results showed that more than 95 % of participants were not aware of PAD. Different levels of PAD awareness have been reported by previous population-based studies in the United States (25 %) [6], Canada (36 %) [7] and the Netherlands (<20 %) [8]. Previous studies have also reported a significantly lower level of public awareness of PAD compared with other cardiovascular diseases such as CVA and coronary artery disease (60–75 %) [6, 7]. However, these previous studies were conducted in Europe or the United States and there are nopublished literatures on awareness of PAD in Asian countries.

We found that being male, an urban resident, and having a higher educational level were predictors of high awareness of PAD. However, those with a history of DM, hypertension, dyslipidemia, smoking, and leg symptoms of PAD did not show a significantly higher level of awareness of PAD. The literature shows that DM, hypertension, dyslipidemia, and smoking are well known as the greatest risk factors for PAD [16‐19]. Therefore, there was a notable gap in awareness in those who are already at risk for PAD.

We also assessed the awareness of possible risk factors and consequences of PAD in the PAD aware group. We found less than one-third of this group was aware that hypertension and smoking were risk factors for PAD.A study in Ireland reported that more than 80 % of the study sample correctly identified smoking as a risk factor for PAD [9]. However, similar to our study, many other studies found that less than 50 % of participants were aware that smoking and hypertension were risk factors for PAD [6, 7]. Although it has been well identified that PAD is associated with an elevated risk of cardiovascular and cerebrovascular events and death from MI and CVA [20‐22], we found that less than 25 % of our “PAD aware” group was aware that MI and CVA are possible consequences of untreated PAD. Many previous studies have also reported that less than 20 % identified CVA and MI as possible consequences of untreated PAD [6, 7]. These results highlight that even among those who are aware of PAD; overall understanding of PAD is poor. We found that very low proportion (10.5 %) of participants had received information on PAD from mass media. In contrast, studies in the United States and Canada reported that 31–33 % of those who were aware of PAD reported public media as their primary source of information [6, 7]. This suggests that information about PAD via public media is scarce in Sri Lanka.

Internationally, peripheral arterial disease or PAD is used in scientific writing and lay communication. Cronin et al. [9] attribute low awareness of PAD to the terminology not being familiar to the public. They highlighted the necessity of simple terminology for PAD to enhance public awareness. Lack of simple and consistent terminology for PAD also might have contributed to the low awareness of PAD in our study. Therefore, simple terminology to describe PAD is an emerging need.

This study highlighted the low awareness of PAD in the general public in Sri Lanka. This low level of awareness may lead to delayed diagnosis, low compliance, and unfavorable outcomes for patients. This shows it is necessary to incorporate PAD to the major NCD prevention programme of the country to enhance public awareness of PAD, including risk factors and preventative methods. A simple terminology to describe PAD is needed to enhance public awareness of PAD.