Chronic diseases and multi-morbidity - a conceptual modification to the WHO ICCC model for countries in health transition

BACKGROUND The burden of non-communicable diseases is rising, particularly in low and middle-income countries undergoing rapid epidemiological transition. In sub-Saharan Africa, this is occurring against a background of infectious chronic disease epidemics, particularly HIV and tuberculosis. Consequently, multi-morbidity, the co-existence of more than one chronic condition in one person, is increasing; in particular multimorbidity due to comorbid non-communicable and infectious chronic diseases (CNCICD). Such complex multimorbidity is a major challenge to existing models of healthcare delivery and there is a need to ensure integrated care across disease pathways and across primary and secondary care. DISCUSSION The Innovative Care for Chronic Conditions (ICCC) Framework developed by the World Health Organization provides a health systems roadmap to meet the increasing needs of chronic disease care. This framework incorporates community, patient, healthcare and policy environment perspectives, and forms the cornerstone of South Africa's primary health care re-engineering and strategic plan for chronic disease management integration. However, it does not significantly incorporate complexity associated with multimorbidity and CNCICD.Using South Africa as a case study for a country in transition, we identify gaps in the ICCC framework at the micro-, meso-, and macro-levels. We apply the lens of CNCICD and propose modification of the ICCC and the South African Integrated Chronic Disease Management plan. Our framework incorporates the increased complexity of treating CNCICD patients, and highlights the importance of biomedicine (biological interaction). We highlight the patient perspective using a patient experience model that proposes that treatment adherence, healthcare utilization, and health outcomes are influenced by the relationship between the workload that is delegated to patients by healthcare providers, and patients' capacity to meet the demands of this workload. We link these issues to provider perspectives that interact with healthcare delivery and utilization. SUMMARY Our proposed modification to the ICCC Framework makes clear that healthcare systems must work to make sense of the complex collision between biological phenomena, clinical interpretation, beliefs and behaviours that follow from these. We emphasize the integration of these issues with the socio-economic environment to address issues of complexity, access and equity in the integrated management of chronic diseases previously considered in isolation.