Non-Communicable Diseases and Urbanization in African Cities: A Narrative Review

*Kenneth Juma, Pamela A. Juma, Constance Shumba, Peter Otieno and Gershim Asiki*

### **Abstract**

Rapid urbanization in Africa has been linked to the growing burden of noncommunicable diseases (NCDs). Urbanization processes have amplified lifestyle risk factors for NCDs (including unhealthy diets, tobacco use, harmful alcohol intake, and physical inactivity), especially among individuals of low and middle social economic status. Nevertheless, African countries are not keeping pace with the ever increasing need for population-level interventions such as health promotion through education, screening, diagnosis, and treatment, as well as structural measures such as policies and legislation to prevent and control the upstream factors driving the NCD epidemic. This chapter highlights the NCD burden in urban Africa, along with the social determinants and existing interventions against NCDs. The chapter concludes by offering insights into policy and legislative opportunities and recommends stronger efforts to apply multisectoral and intersectoral approaches in policy formulation, implementation, and monitoring at multiple levels to address the NCD epidemic in African cities.

**Keywords:** NCDs, risk factors, urbanization, African cities, Africa

### **1. Introduction**

Over the last few decades, the proportion of the world's population living in urban areas has grown to 55%, and is expected to increase to 68% by 2050 [1]. Africa's urban growth is unfolding more rapidly than anywhere in the world, with the share of urban dwellers projected to exceed 50% by 2035 [1]. However this growth has been characterized as "rapid, unplanned and unmanaged" because 62% of the urban population in Africa lives in informal settlements characterized by conditions of squalor, overcrowding, and small make-shift structures mostly made of sub-standard housing materials such as mud and scraps of wood or corrugated metal [2]. Unplanned settlement in cities is associated with increased inequality, urban poverty, social deprivation and lifestyle changes that could lead to an increased burden of non-communicable diseases (NCDs) [3]. Thus, changes in physical and social environment in the urban space favor the adoption of behaviors that promote unhealthy lifestyles such as physical inactivity, unhealthy diets, tobacco consumption and harmful alcohol consumption that predispose individuals living in the slums to NCDs [4, 5]. Even so, there is generally lack of consensus as to whether there exists any NCDs health advantages in urban area.

NCDs represent a leading threat to human health and development [6]. In 2015 alone, four major NCDs-cardiovascular diseases (CVDs), cancers, diabetes, and chronic respiratory diseases accounted for 72% of all deaths globally; 85% of these were from low and middle income countries (LMICs) [7]. In urban areas of SSA, NCDs are rising faster than anywhere else in the world [8]. The economic consequences of NCDs are enormous across the globe, and are felt at the individual, household, community and health systems levels. Bloom et al. (2011) [9], estimated that economic losses due to NCDs could amount to approximately 75% of the global GDP. While there is wider recognition of the increasing burden of NCDs across Africa [5], scanty literature exists on the link between urban environments and NCD risks in Africa, as well as the associated health and social consequences, and access to health services. Considering that future population growth will take place predominantly in African cities, there is need for a deeper understanding of urban health and the context of NCDs in African cities to identify tailored interventions to curb the epidemic. Urbanization in sub-Saharan Africa provides a unique opportunity to explore the mechanisms by which urban environment influences NCD epidemiology.

This chapter describes both the health determinants and outcomes in African cities with special attention to low-income urban areas. It further highlights the burden, impact and possible interventions for NCDs in African cities. The chapter draws on insights from relevant peer-reviewed and gray literature on NCDs, and the authors' own experiences on the subject in Africa.
