Commentary: Societal influences on cardiovascular disease: time to assess and act

Cardiovascular diseases (CVDs) are among the leading cause of morbidity and mortality worldwide. The burden of this epidemic is likely to worsen as developing countries with large populations witness rapid economic, social and cultural transition. Such changes, while leading to prosperity and increased longevity of their populations, also produce rapid epidemiological transition resulting in an increased non-communicable disease burden. Economic development, urbanization and globalization result in dramatic changes in dietary practices, inadequate physical activity, increased tobacco consumption and environmental pollution. Cheaper availability of highfat foods and diminishing use of traditional foods result in high energy intake, whereas mechanization results in reduced physical activity and lower energy expenditure. These result in energy surplus and consequent overweight and obesity. Additionally, migration, loss of a social support system and break down of family networks lead to increased stress. All these fuel the CVD epidemic and hence CVDs are often termed lifestyle diseases. We now understand that there are multiple determinants of health and several dimensions of health care, many of which span the non-health sector. Therefore, a comprehensive CVD control comprises several approaches involving policy-level changes to the management of individuals with CVD and its complications. However, what is now clear is that the decline in CVD in developed countries over the past few decades has largely resulted from policy changes aimed at promoting healthy behaviours as well as advances in clinical care. A rough estimate suggests that two-thirds of the observed decline in coronary heart disease (CHD) mortality can be attributed to population risk approach of shift in diet and smoking. In the UK, more than two-thirds of the life years gained due to reduction in CHD mortality during 1981–2000 has been attributed to a decline in smoking. Despite this, the population level influences in determining CVD risk and the role of interventions aimed at populations to reduce CVD have not been well documented. In this issue, Chow et al. present a comprehensive review of population-level interventions and their impact on CVD risk factors and diseases. They use an iterative process in collating literature to address the role of population-level factors in CVD prevention. As exemplars they use tobacco control, built environment, dietary interventions and environmental pollution. Using a narrative review process they summarize several studies in these domains and argue the need for multidisciplinary research in evaluating population-based approaches and highlight the methodological challenges such as the deficits in the currently available instruments that evaluate diet, nutrition and physical activity. They believe that the estimates of benefits emanating from population-level interventions do not come from actual research evidence, but are obtained largely due to a ‘diagnosis of exclusion’. They suggest additional research to evaluate the role of population-based interventions.