Global Burden of Cardiovascular Diseases: Part I: General Considerations, the Epidemiologic Transition, Risk Factors, and Impact of Urbanization

According to published data, between 1984 and 1994 mortality rates in Russia initially underwent a rapid decline followed by an even steeper increase. In 1994, male life expectancy at birth was 57.6 years, having fallen by 6.2 years since 1990. There has been concern that such striking fluctuations in mortality are an artefact, although, among other factors, alcohol consumption has been implicated. We analysed the age-specific and cause-specific patterns of mortality decrease and increase by use of data from a newly reconstructed mortality series for Russia so that we could examine the plausibility of various explanations for the mortality trends. All major causes of death, with the exception of neoplasms, showed declines in mortality between 1984 and 1987 and increases between 1987 and 1994. In relative terms, these tended to be largest for the age-group 40-50 years; surprisingly, they were of the same magnitude among women and men. The largest declines and subsequent increases in proportional terms were observed for alcohol-related deaths and accidents and violence. However, pronounced effects were also seen for deaths from infections, circulatory disease, and respiratory disease. No substantial variations were seen for neoplasms. The stability of mortality from neoplasms in contrast to other causes over the period 1984-94 largely precludes the possibility that the changes in life expectancy are mainly an artefact, particularly one due to underestimation of the population. Although factors such as nutrition and health services may be involved, the evidence is that substantial changes in alcohol consumption over the period could plausibly explain the main features of the mortality fluctuations observed. These results provide a major challenge to public health in Russia and to our understanding of the determinants of alcohol consumption and its role in explaining mortality patterns within and between many other countries.

The effect of passive smoking on the risk of coronary heart disease is controversial. We conducted a meta-analysis of the risk of coronary heart disease associated with passive smoking among nonsmokers. We searched the Medline and Dissertation Abstracts Online data bases and reviewed citations in relevant articles to identify 18 epidemiologic (10 cohort and 8 case-control) studies that met prestated inclusion criteria. Information on the designs of the studies, the characteristics of the study subjects, exposure and outcome measures, control for potential confounding factors, and risk estimates was abstracted independently by three investigators using a standardized protocol. Overall, nonsmokers exposed to environmental smoke had a relative risk of coronary heart disease of 1.25 (95 percent confidence interval, 1.17 to 1.32) as compared with nonsmokers not exposed to smoke. Passive smoking was consistently associated with an increased relative risk of coronary heart disease in cohort studies (relative risk, 1.21; 95 percent confidence interval, 1.14 to 1.30), in case-control studies (relative risk, 1.51; 95 percent confidence interval, 1.26 to 1.81), in men (relative risk, 1.22; 95 percent confidence interval, 1.10 to 1.35), in women (relative risk, 1.24; 95 percent confidence interval, 1.15 to 1.34), and in those exposed to smoking at home (relative risk, 1.17; 95 percent confidence interval, 1.11 to 1.24) or in the workplace (relative risk, 1.11; 95 percent confidence interval, 1.00 to 1.23). A significant dose-response relation was identified, with respective relative risks of 1.23 and 1.31 for nonsmokers who were exposed to the smoke of 1 to 19 cigarettes per day and those who were exposed to the smoke of 20 or more cigarettes per day, as compared with nonsmokers not exposed to smoke (P=0.006 for linear trend). Passive smoking is associated with a small increase in the risk of coronary heart disease. Given the high prevalence of cigarette smoking, the public health consequences of passive smoking with regard to coronary heart disease may be important.