Multimorbidity in Sub-Saharan Africa: focusing on the national prevalence and the response of primary care in Botswana

Abstract

INTRODUCTION: Multimorbidity, defined as the coexistence of two or more chronic conditions in an individual, poses a profound global public health challenge, with far reaching implications for affected individuals, their families and healthcare systems. Although research on multimorbidity has gained momentum in recent years, most of the existing evidence originates from High Income Countries (HICs), where disease patterns and healthcare systems substantially differ from those in Low- and-Middle-Income Countries (LMICs). Within the context of sub Saharan Africa (SSA), Botswana, like many other countries in the region, is experiencing a dramatic increase in the burden of noncommunicable diseases (NCDs), coinciding with one of the world’s highest incidence of HIV/AIDS. This rising burden of NCDs is primarily attributed to demographic shifts, adoption of westernised and urban lifestyles, and cumulative exposure to other NCD risk factors within the general population. Additionally, Botswana has achieved remarkable success in implementing antiretroviral therapy (ART) programs, leading to prolonged life expectancy for people living with HIV (PLWHIV). Consequently, this achievement significantly contributes to the escalating burden of NCDs within the population, creating a dual burden of these conditions.

As the epidemiological landscape evolves, there is a compelling call for action, urging the government to adopt and strengthen primary health care (PHC) in response to this dual burden of disease. At the heart of this call is the pressing need for service integration, a strategy designed to optimise resource allocation and empower healthcare providers to deliver comprehensive care and support to individuals grappling with multimorbidity. Recent observations pertaining to the COVID-19 pandemic further underscored the heightened vulnerability of individuals with underlying chronic conditions to severe complications and mortality. This emerging evidence emphasised the predicament faced by healthcare systems, particularly in LMICs, as they grappled with the dual challenge of containing the virus's spread and managing chronic conditions. Therefore, gaining a comprehensive understanding of multimorbidity patterns and its management becomes of paramount importance.

My thesis thus aims to investigate the epidemiology of chronic disease multimorbidity in Botswana, with a specific focus on the intersection of chronic communicable diseases such as HIV/AIDS and tuberculosis (TB) with NCDs, and to understand the strategies that can be adopted to improve care for people with multiple chronic conditions.

The following specific objectives were formulated to achieve the aim of my thesis: 1. To assess and summarise the evidence on the epidemiology of chronic disease multimorbidity in SSA 2. To determine the prevalence and patterns of chronic disease multimorbidity among the adult population in Botswana. 3. To examine socio-demographic and lifestyle factors associated with chronic disease multimorbidity among the adult population in Botswana. 4. To explore perceptions and experiences of health care providers and policymakers on care and management of patients with multimorbidity in Botswana. 5. To provide a deeper understanding of what is understood by multimorbidity in the local context and recommendations to inform provision of care for patients with multimorbidity in primary care settings in Botswana.

METHODS: Using a convergent mixed methods approach, my study was divided into three components. In the first study, I performed a systematic literature review following the PRISMA guidelines, to assess and synthesise the evidence on the prevalence and patterns of chronic disease multimorbidity among adults in the SSA region. I conducted an extensive literature search across multiple databases and sources including grey literature for observational studies reporting on the prevalence, patterns, and epidemiology of multimorbidity in SSA, published between January 2000 and December 2020. Given the heterogeneity in multimorbidity definitions and populations, a narrative synthesis of the findings was adopted.

In the quantitative phase of this study, I conducted secondary analysis of cross-sectional data from the 2017 Botswana Demographic Survey (BDS). The BDS is a nationally representative survey commissioned and administered by the government of Botswana through Statistics Botswana, the country's official statistics authority. The survey encompassed a wide range of sociodemographic information and collected self-reported data on the presence of various health conditions. For the purposes of this study, I focused my analysis on participants aged 18 year and above and assessed multimorbidity using 16 self-reported chronic conditions including communicable diseases, and various NCDs. Multiple logistic regression models were used to investigate the association of multimorbidity with demographic, socioeconomic, and lifestyle factors.

The third study involved qualitative interviews that aimed to explore the experiences and perceptions of healthcare workers and policymakers regarding the care and management of patients with multimorbidity, barriers and enablers, and their views on how primary care can be strengthened to best deal with multimorbidity in Botswana. Participants were recruited using purposive and snowball sampling techniques in 4 health districts. 27 semistructured telephone interviews were conducted, transcribed verbatim, and analysed using thematic analysis with the aid of Nvivo 12.

RESULTS: The systematic review identified 37 studies reporting multimorbidity prevalence and patterns among adults in SSA, conducted across twelve countries. These studies predominantly employed cross-sectional designs, with only a few utilizing cohort data. Sample sizes varied considerably, ranging from 142 to 47,334 participants. Prevalence estimates exhibited remarkable heterogeneity, largely due to methodological variations in the number and types of conditions considered, study settings, and participant demographics. Conditions varied in number, with studies incorporating as few as 3 to as many as 30 chronic conditions. Notably, the prevalence of multimorbidity ranged from 1.4% to 69.4%. Additionally, the review revealed diverse patterns of multimorbidity, with HIV and TB frequently co-occurring with conditions like hypertension, diabetes, anaemia, and depression.

For the prevalence study 15,512 adults aged 18 years and older were included in the analysis. Multimorbidity was defined as the presence of two or more of the 16 self-reported conditions. The most prevalent conditions were hypertension (14.3%), HIV/AIDS (13.9%), asthma (3.4%), tuberculosis (2.2%) and gastric ulcers (2.1%). The findings revealed that 4410 (25.3%) of participants had at least one chronic condition. Multimorbidity was present in 1558 (9%) of the population and was independently associated with factors such as age, female gender, marital status, education level, residence, and BMI. The findings further revealed that among individuals with multimorbidity, hypertension (65%) and HIV/AIDS (43.4%) were the most prevalent chronic conditions, significantly shaping the multimorbidity patterns. A descriptive analysis of disease pairs identified the top five dyads, including hypertension and HIV (24.1%), hypertension and diabetes (18.8%), HIV and tuberculosis (9.9%), hypertension and rheumatism (9.1%), and hypertension and cardiovascular disease (8.2%), underscoring the prominence of hypertension in co-occurring conditions, with HIV/AIDS as the second most prevalent comorbidity.

I interviewed 14 primary care workers from different facilities in the 4 health districts, and 13 policymakers with diverse professional roles within the healthcare system of Botswana, both at national and regional level. The findings were explored under six thematic areas, which described how healthcare professionals conceptualised multimorbidity, how care for chronic diseases and multimorbidity is organised, the barriers, and challenges they face in providing care. While there were subtle variations in the terminology used, the core understanding of multimorbidity as the presence of multiple health conditions was shared by both healthcare workers and policymakers.

The significance and complexity of multimorbidity were acknowledged, particularly in relation to the interplay between HIV/AIDS and NCDs. The findings revealed that the current healthcare system is characterised by vertical disease programs, limited funding for NCDs and lack of integration, often leading to fragmented services for patients with multiple chronic conditions. Additionally, the absence of comprehensive multimorbidity care guidelines, poor communication among professionals, extended waiting times, and persistent shortages of personnel and essential medications, were highlighted as some of the barriers in provision of multimorbidity care.

Respondents articulated several recommendations aimed at enhancing multimorbidity care in Botswana. These encompassed multi-sectoral collaboration, integration of health services, increased staffing, health education, community engagement, policy changes, and the promotion of preventive care, among many other factors. Finally, the role of research in guiding evidence-based decision-making to improve multimorbidity care in Botswana was emphasised throughout the interviews.

CONCLUSION: This study examined the epidemiology and complexities of chronic disease multimorbidity in in the SSA context, considering the coexistence of chronic communicable and noncommunicable diseases. The limited evidence from SSA region, as highlighted by the systematic review, underscores a significant research gap in the region. The reliance on limited data sources, such as the WHO SAGE dataset, also highlights the need for comprehensive and contextspecific data. The prevalence study was the first to explore multimorbidity with HIV and TB included in the list of conditions. The study revealed the substantial burden of chronic conditions and their intersections. This was further emphasised by the healthcare professionals as they provided valuable insights into the observed multimorbidity patterns in their daily work. Effective multimorbidity management strategies should consider the coexistence of NCDs and communicable diseases, socioeconomic disparities, patient-related obstacles, and healthcare system challenges. Collaboration between stakeholders, policy changes, and research-based decision-making can contribute to improved patient care and better outcomes in Botswana's healthcare system.