Epidemiology of lower extremity artery disease in a rural setting in Benin, West Africa: The TAHES study

Highlights

• Prevalence of LEAD is estimated at 5.5% in a rural population of Benin.

• Women and people over 55 years old have higher prevalence of LEAD.

• Tobacco and hypertension did not influence the prevalence of LEAD in this population.

Introduction

Cardiovascular diseases (CVD) are the leading cause of death worldwide and are mainly due to atherosclerosis [1]. Lower extremity artery disease (LEAD) is one of the main localizations of atherosclerosis, but also a risk marker of cardiovascular events. Globally, 202 million people were living with LEAD in 2010 (more than people living with HIV), and 69.7% of them in Low and Middle-Income Countries (LMIC). During 2001–2010 the number of individuals with LEAD increased respectively by 28.7% in LMIC and 13.1% in High Income Countries (HIC) [2]. LEAD has been widely studied in HIC. In those studies, LEAD often appears after the age of 50 years old [3], and is associated with a high level of cardiovascular risk factors such as smoking, diabetes or hypertension [4,5]. When diagnosed by the ankle-brachial index (ABI), it affects more frequently women than men, more old than young people [2,6] and more often Blacks individuals than non-Hispanic Whites [7]. In addition, LEAD impairs quality of life and increases risk of major cardiovascular events (coronary and cerebral arterial diseases), amputation (>60%) and death [8,9].

Data available in Sub-Saharan Africa (SSA) are generally from specifics populations (surgery, diabetes, elderly) and show higher prevalence than in HIC (range from 15% to 32,4%), but with fairly marked disparities between neighboring countries, rural and urban areas [[10], [11], [12], [13], [14], [15]]. Those disparities make it difficult to draw accurate conclusions about the burden of LEAD in Africa. There is a need for more comprehensive data that accounts for high prevalence of CVD in young subjects in LMIC [16]. Therefore, gathering additional evidence using standardized methods to measure LEAD is critical to better assess the disease distribution in LMIC [9].

Symptoms of LEAD are often absent, atypical or underestimated, leading to diagnosis in the most severe stages [17,18]. The use of ABI gives an objective measure with high level of specificity (83.3–99.0%) but variable levels of sensibility (15–79%) [19]. The ABI has been developed to facilitate detection of cases since it does not require expensive equipment. It is also considered to be the first-line screening test to define both symptomatic and asymptomatic LEAD, objectively in epidemiological studies, as well as in clinical settings [9]. It was therefore adopted as part of this work which aimed to describe the prevalence of LEAD and analyze associated factors in the “Tanve Health Study” (TAHES) cohort in Tanve, a village of Benin.