Global trends in CVD are based on models that use country-specific data from a diverse range of developed and developing countries including those of the European Union (HEM Project Team, 2008; Kotseva et al., 2009a), Saudi Arabia (Al-Hamdan et al., 2005), Pakistan (Nishtar et al., 2004), South Africa (Steyn, 2006), China (Yang et al., 2008), Indonesia (Ng, 2006; Ng et al., 2006), Mexico (Fernald and Neufeld, 2007), India (Goyal and Yusuf, 2006; Reddy, 2007), and the United States (Danaei et al., 2009; Flegal et al., 2007). Over the past decade, the quality and availability of country-specific data on CVD risks, incidence, and mortality has increased in accordance with one of the major recommendations of the 1998 IOM report. What emerges are nationally derived data on risks and CVD outcomes. Therefore, in many developing countries, the lack of country-specific data on risks and CVD outcomes that was prominently highlighted in the 1998 IOM report is less of an impediment to policy development and action.
Nonetheless, before beginning a discussion of CVD trends and risk factor incidence around the world and in specific countries and regions, it is important to note several persistent limitations with the available data. Although many countries have established health surveillance systems with death registration data, the quality of the data collected varies substantially across countries. In many countries—especially in low and middle income countries—health statistics are often based on surveillance that does not cover all areas of the country, is incomplete in the areas it does cover, or is collected by undertrained staff who do not, or cannot, accurately report the pertinent data. These realities limit the reliability of some country health data (Mathers et al., 2005; Rao et al., 2005). Despite these limitations, WHO and country health statistics are often the most complete, comparable, or only data available and thus remain a key tool for evaluating the status of a CVD epidemic within and between countries. The importance of country-level epidemiological data and the ongoing need to standardize methodologies, increase data collection capacity, and improve the accuracy of national reporting are discussed further in Chapter 4.
This chapter uses the most recent data available in each area discussed below, such as deaths by cause, contributions of risk factors to deaths by cause, the composition by risk factor of deaths by a specific cause, and risk factor levels. This introduces some inconsistencies as not all data cited comes from a single source. However, there is available data that is more recent for some of these measures than for others, and this was valued above the consistency of a single data source. Wherever possible, this chapter references burden, incidence, and prevalence data from countries’ national health statistics, WHO country and global statistics (which are based on