“As populations move from conditions of under-development towards industrialised societies, the cardiovascular disease profile changes from one related to infections and under-nutrition. In the second stage, hypertensive heart disease and haemorrhagic stroke predominate. This is followed by the stage of increasing obesity, diabetes, all forms of stroke and IHD affecting young ages. The fourth stage is indicated by a shift in the IHD and stroke mortality to older ages, and is the current experience of many Western countries. Yusuf et al have added the final stage based on the experience in parts of Eastern Europe with the re-emergence of conditions related to infections and alcohol.”
Steyn and Schneider say “It was anticipated that this increase in chronic diseases would occur in poor countries undergoing industrialisation, development and adoption of typical westernised lifestyles. Initially the chronic diseases emerged in the wealthier sector of society, however, in the last quarter of the 20th century these conditions occurred more frequently in the poor, than in the wealthy, typically westernised, industrialised countries. In wealthier countries, chronic diseases are ameliorated through healthier eating and smoking patterns that arise from education (citing several sources)”
“On the basis of observations from some large middle-income populations (citing Frenk) proposed modifications to Omran’s theory with the protracted-polarised model of epidemiological transition. This model is characterized by the coexistence of infectious and chronic diseases in the same population persisting for a long time. In the protracted model more affluent sections of the population would have completed the transition, while economically disadvantaged groups continue to suffer from pre-transitional pathologies. A feature of the protracted-polarised model is the juxtaposition of a developed and an underdeveloped sector of the population. The model has its roots in inequality and the emerging health patterns further aggravate this.”
“A consequence of the protracted-polarised model in developing countries with limited resources is the enormous burden placed on the health services to cater for multiple burdens of diseases. In this situation it is clear that the chronic diseases are less likely to be adequately provided for when competing with the more acute and urgent conditions such as patients with trauma or those severely ill with active infections. Chronic diseases lack urgency at every level of resource allocation and consequently, unless a health service has a scientifically based process of priority setting to ensure appropriate resource allocation, chronic diseases seldom receive the resource allocations required for prevention and cost-effective care.”
“Furthermore, health services in poorer countries are largely based on a model for treating acute illness. Such a model, particularly in public sector clinics catering for the poor, rarely provides for the appropriate health promotion initiatives or educational needs of patients with chronic disease. For example, the logistics of dispensing long-term medication for chronic diseases is seldom organised so that patients can obtain repeat prescriptions in an efficient way.”
