Health system determinants of tuberculosis mortality in South Africa: a causal loop model

Abstract

Background Tuberculosis (TB) is a major public health concern in South Africa and TB-related mortality remains unacceptably high. Numerous clinical studies have examined the direct causes of TB-related mortality, but its wider, systemic drivers are less well understood. Applying systems thinking, we aimed to identify factors underlying TB mortality in South Africa and describe their relationships. At a meeting organised by the ‘Optimising TB Treatment Outcomes’ task team of the National TB Think Tank, we drew on the wide expertise of attendees to identify factors underlying TB mortality in South Africa. We generated a causal loop diagram to illustrate how these factors relate to each other. Results Meeting attendees identified nine key variables: three ‘drivers’ (adequacy & availability of tools, implementation of guidelines, and the burden of bureaucracy); three ‘links’ (integration of health services, integration of data systems, and utilisation of prevention strategies); and three ‘outcomes’ (accessibility of services, patient empowerment, and socio-economic status). Through the development and refinement of the causal loop diagram, additional explanatory and linking variables were added and three important reinforcing loops identified. Loop 1, ‘Leadership and management for outcomes’ illustrated that poor leadership led to increased bureaucracy and reduced the accessibility of TB services, which increased TB-related mortality and reinforced poor leadership through patient empowerment. Loop 2, ‘Prevention and structural determinants’ describes the complex reinforcing loop between socio-economic status, patient empowerment, the poor uptake of TB and HIV prevention strategies and increasing TB mortality. Loop 3, ‘System capacity’ describes how fragmented leadership and limited resources compromise the workforce and the performance and accessibility of TB services, and how this negatively affects the demand for higher levels of stewardship. Conclusions Strengthening leadership, reducing bureaucracy, improving integration across all levels of the system, increasing health care worker support, and using windows of opportunity to target points of leverage within the South African health system are needed to both strengthen the system and reduce TB mortality. Further refinement of this model may allow for the identification of additional areas of intervention.

Leveraging HIV Care Infrastructures for Integrated Chronic Disease and Pandemic Management in Sub-Saharan Africa

“…In Sub-Saharan Africa (SSA), declining rates of extreme poverty [1,2] have been accompanied by increasing rates of non-communicable diseases (NCDs) [3][4][5][6][7], persistent burdens of infectious disease [8][9][10][11][12], and emerging pathogens such as the novel coronavirus (COVID-19) [13]. Given the magnitude of the epidemics of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) and tuberculosis (TB), targeted resources have come from donor nations, the U.S. President's Emergency Plan for AIDS Relief (PEPFAR), the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund), and ministries of health to scale-up testing and treatment [14].…”

Diverse Approaches to Creating and Using Causal Loop Diagrams in Public Health Research: Recommendations From a Scoping Review

“…In terms of research aims found in the 23 articles, four themes emerged: 1) to examine the complexity of a public health topic and illustrate complex systems thinking [26][27][28][29][30][31][32][33][34]; 2) to discuss the complexity of a public health intervention [35][36][37][38][39][40]; 3) to describe study protocol and how CLDs were created [41][42][43][44]; and 4) to illustrate how CLDs can be used to monitor and track initiatives to improve population health or evaluate impact of interventions [45][46][47][48].…”

“…Both primary and secondary data were used for creating CLDs (Table 3). Most articles reported on primary data collection (18/ 23) and this included interviews [26,27,33,[35][36][37][38][39][40], group model building with stakeholders and/or community members [32,41,43,44,46,48], behavioral data [42,47], fieldnotes [37], and workshops with experts [31]. Twelve articles used primary data only.…”

“…Allender [47] ✓ ✓ Araz [45] ✓ ✓ Bensberg [35] ✓ ✓ Bradley [34] ✓ ✓ Brereton [28] ✓ ✓ Brown [48] ✓ ✓ Burrell [36] ✓ ✓ ✓ Clarke [37] ✓ ✓ ✓ Crielaard [26] ✓ ✓ ✓ Eker [27] ✓ ✓ Gerritsen [41] ✓ ✓ Hassmiller Lich [46] ✓ ✓ Jalali [38] ✓ ✓ ✓ Klement [29] ✓ ✓ Knai [30] ✓ ✓ Maitland [42] ✓ ✓ Osman [31] ✓ ✓ Owen [39] ✓ ✓ Parmar [40] ✓ ✓ ✓ Riley [43] ✓ ✓ Sahin [32] ✓ ✓ ✓ Swierad [44] ✓ ✓ Urwannachotima [33] ✓ ✓…”

“…Many articles reported on the use of software for creating the actual diagram. Vensim [31,35,37,39,40,[44][45][46], Stella Architect [28], and STICK-E [43] were the three diagrammatic programs used. Further to the actual diagram, there was a wide array of CLD types and degrees of diagram readability.…”