Comparison of global estimates of prevalence and risk factors for peripheral artery disease in 2000 and 2010: a systematic review and analysis

Summary

Background

Lower extremity peripheral artery disease is the third leading cause of atherosclerotic cardiovascular morbidity, following coronary artery disease and stroke. This study provides the first comparison of the prevalence of peripheral artery disease between high-income countries (HIC) and low-income or middle-income countries (LMIC), establishes the primary risk factors for peripheral artery disease in these settings, and estimates the number of people living with peripheral artery disease regionally and globally.

Methods

We did a systematic review of the literature on the prevalence of peripheral artery disease in which we searched for community-based studies since 1997 that defined peripheral artery disease as an ankle brachial index (ABI) lower than or equal to 0·90. We used epidemiological modelling to define age-specific and sex-specific prevalence rates in HIC and in LMIC and combined them with UN population numbers for 2000 and 2010 to estimate the global prevalence of peripheral artery disease. Within a subset of studies, we did meta-analyses of odds ratios (ORs) associated with 15 putative risk factors for peripheral artery disease to estimate their effect size in HIC and LMIC. We then used the risk factors to predict peripheral artery disease numbers in eight WHO regions (three HIC and five LMIC).

Findings

34 studies satisfied the inclusion criteria, 22 from HIC and 12 from LMIC, including 112 027 participants, of which 9347 had peripheral artery disease. Sex-specific prevalence rates increased with age and were broadly similar in HIC and LMIC and in men and women. The prevalence in HIC at age 45–49 years was 5·28% (95% CI 3·38–8·17%) in women and 5·41% (3·41–8·49%) in men, and at age 85–89 years, it was 18·38% (11·16–28·76%) in women and 18·83% (12·03–28·25%) in men. Prevalence in men was lower in LMIC than in HIC (2·89% [2·04–4·07%] at 45–49 years and 14·94% [9·58–22·56%] at 85–89 years). In LMIC, rates were higher in women than in men, especially at younger ages (6·31% [4·86–8·15%] of women aged 45–49 years). Smoking was an important risk factor in both HIC and LMIC, with meta-OR for current smoking of 2·72 (95% CI 2·39–3·09) in HIC and 1·42 (1·25–1·62) in LMIC, followed by diabetes (1·88 [1·66–2·14] vs 1·47 [1·29–1·68]), hypertension (1·55 [1·42–1·71] vs 1·36 [1·24–1·50]), and hypercholesterolaemia (1·19 [1·07–1·33] vs 1·14 [1·03–1·25]). Globally, 202 million people were living with peripheral artery disease in 2010, 69·7% of them in LMIC, including 54·8 million in southeast Asia and 45·9 million in the western Pacific Region. During the preceding decade the number of individuals with peripheral artery disease increased by 28·7% in LMIC and 13·1% in HIC.

Interpretation

In the 21st century, peripheral artery disease has become a global problem. Governments, non-governmental organisations, and the private sector in LMIC need to address the social and economic consequences, and assess the best strategies for optimum treatment and prevention of this disease.

Funding

Peripheral Arterial Disease Research Coalition (Europe).

Introduction

Chronic non-communicable diseases (NCDs) are now the leading cause of morbidity and mortality not only in high-income countries (HIC), but also in low-income or middle-income countries (LMIC).1, 2 Over the next decade, the global burden of NCDs will grow rapidly, driven mainly by an ageing world population and increased exposure to chronic disease risk factors in LMIC.3, 4 The global pandemic of NCDs was the main topic of a UN high-level meeting in 2011.⁵ One of the first tasks required for a coordinated and cost-effective response is to quantify the current burden of the most important NCDs and their global and regional spread. This effort will probably be met with a paucity of information from most LMIC, which will be particularly true for diseases that are still relatively neglected even in HIC. One of the best examples is lower limb peripheral artery disease, the third leading cause of atherosclerotic vascular morbidity after coronary heart disease and stroke. About 10–20% of people with peripheral artery disease have intermittent claudication,6, 7 another 50% have atypical leg symptoms,⁷ and those without exertional leg pain have poor mobility compared with individuals without peripheral artery disease.⁸ Patients with and without leg ischaemic symptoms have roughly a three-fold increase in risk of mortality and major cardiovascular events (heart attack and stroke) compared with those without peripheral artery disease.9, 10, 11

To develop effective policies and programmes for the global prevention and management of peripheral artery disease, population surveillance data and studies of risk factors are crucial, but lacking in many HIC and particularly in LMIC. Currently, there are no reliable estimates of the global prevalence of peripheral artery disease. Moreover, in assessing the global transition in cardiovascular disease in recent years,¹² attention has been focused on the decline in coronary heart disease and stroke in HIC, the corresponding increase in many LMIC, and the risk factors that might be driving this change.13, 14 Little attention has been paid to peripheral artery disease.

We did a rigorous systematic analysis of all the evidence available in the public domain to identify epidemiological studies of peripheral artery disease of acceptable quality. Using the information from those studies, we aimed to: (1) provide the first comparison of age-specific and sex-specific prevalence of peripheral artery disease between HIC and LMIC; (2) establish the main risk factors for peripheral artery disease in HIC and LMIC; and (3) provide robust estimates of the number of people living with peripheral artery disease regionally and globally.