Research and Development
Even though most of the interventions currently available appear to be expensive and complex for developing countries, the demand for effective care for cardiovascular diseases will exert major pressure on health systems in coming decades. Increased use of these procedures is already documented in China and India (Murray and Lopez 1994, 1997; Unger 1999). In this context, cardiovascular research should be concentrated in the fields of primary prevention, health services, clinical guidelines, clinical research, and epidemiology.
Primary Prevention
Because the control of many cardiovascular risk factors is strongly related to the legislative environment—for example, that pertaining to tobacco use or nutrition—the design and implementation of appropriate laws and regulations is likely to increase in developing countries. However, any such initiatives need to be monitored and systematically evaluated, especially to estimate the magnitude of the reduction achieved.
Another area of research is the assessment of chemoprophylaxis in primary prevention. Multidrug combinations such as the hypothetical "polypill" are likely to be the first practical initiative of a long list of important innovations. Both the efficacy and the effectiveness of new interventions in primary prevention should be evaluated as a matter of urgency, because no results of large-scale clinical trials in developing countries are as yet available.
Health Services
Capacity building—more specifically, education and training—of health care workers in developing countries, is a major issue for the future, along with critical evaluations of the performance of health workers. Such evaluations should compare various capacity-building strategies; for instance, they could compare the delivery of simplified regimens of care by community health workers versus delivery of care by trained health professionals.
The dissemination of innovations deserves special attention in a context of scarce resources (Berwick 2003). The transfer of technologies to developing countries should be made on cost-effectiveness criteria, which implies analysis conducted in the specific situation of developing countries—for example, cost-effectiveness for thrombolytics in a developing country might be much worse than in the United States if getting to a hospital on time is a problem. Sensitivity analysis of the cost-effectiveness of surgical and medical interventions in developing countries is also needed.
Furthermore, the appropriate incentives for technological changes in health care should be investigated (McClellan and Kessler 1999). This line of research includes analyses of the pricing of technologies (including drugs) or of new designs for services, such as point-of-care devices for use by community health workers.
The long period of incubation of CVD opens up opportunities for extensive screening based on preclinical signs and biomarkers. However, strong lines of research are needed to secure effective and safe screening programs and should include opportunistic screening for places where visits to health centers are limited.
Finally, all assessments made in relation to health services research should take into account the costs related to scaling up any procedure evaluated.
Clinical Guidelines
The diffusion of health technologies usually leads to a widening of the clinical indication beyond the evidence-based scope of the intervention (PTCA is a classic example) (Dravik 1998), corresponding to a decrease not only in the procedure's efficacy, but also in its effectiveness (Anderson and Lomas 1988; Blustein 1993). Several studies suggest that overuse and underuse tend to coexist in the same community and that even severe scarcity of resources does not protect against overuse of cardiological interventions, at least among certain segments of the population (Joorabchi 1979; Soumerai and others 1997).
The consequences of such trends are more dramatic in developing than developed countries. Therefore, the introduction of costly care should be accompanied by a corresponding effort in relation to the provision of formal education to providers and prescribers, complemented by the development of clinical guidelines aimed at avoiding both the overuse and the underuse of procedures.
Clinical guidelines are already numerous, but all have been established in affluent countries. A new, specific effort should be made in developing countries to address local issues, such as problems related to the availability of procedures or drugs or to accessibility of services, and the development and maintenance of these guidelines should follow best available standards.
Clinical Research
In most situations, health care innovations should be introduced as experimental interventions to permit proper monitoring and evaluation. These experiments do not have to address the efficacy of the procedure (many innovations will already have been tested), but rather issues pertaining to their effectiveness and efficiency in the specific context of developing countries.
Another reason for the experimental approach is the rapidity with which the field of CVD is evolving. It is not reasonable, at the local level, to wait until the publication of trial results and meta-analyses, which often takes place years after changes have occurred in everyday practice. For this reason, a new culture of clinical research should be developed in which every innovation should be taken as an opportunity for systematic experimental evaluation.
Among various topics in clinical research, adherence deserves special mention. On average, 50 percent of patients in developed countries do not take their prescribed medicines after one year, despite having full access to medicines. In developing countries, this poor adherence is made worse by poor access to health services and drugs, to lack of education, and to other factors (Bovet and others 2002; WHO 2003a). Options for improving adherence should be designed and experimented with.
Epidemiological Research
A basic task of epidemiological research is to assess geographic and secular trends in the distribution of risk factors. Of special relevance is the movement from regional to country levels and the trend within a country. The impact of poor health status in early life should be assessed from the impact of poor fetal health to the consequence of multiple childhood infections on the risk for CVD. Because of the scarce availability of resources, the development and maintenance of health care should be supported by a comprehensive information system. Simple, affordable health information systems are preferable along the lines of the framework developed by the World Health Organization.
