In recent years an increasing emphasis has been placed on the need for improved primary prevention of cardiovascular disease. To this end, using evidence from clinical trials and epidemiological studies, the American Heart Association (AHA) has suggested seven ideal cardiovascular health behaviours (metrics), including: not smoking; being physically active; having normal blood pressure, blood glucose and total cholesterol levels, and weight; and eating a healthy diet. However, no previous study has investigated the relationship between the prevalence of these lifestyle factors and cardiovascular mortality on a national scale.
Therefore this paper used the National Health and Nutrition Examination Survey (NHANES) in the USA to examine the time trends of these 7 cardiovascular health behaviours among 44 959 persons 20 years or older and to estimate their relationship to the risk of all-cause and cardiovascular (CVD) mortality. The main outcome measures included all-cause, cardiovascular, and ischemic heart disease (IHD) mortality.
The authors found that few study participants met all 7 cardiovascular health metrics (2.0% in 1988-1994, 1.2% in 2005-2010). Overall 2673 all-cause, 1085 cardiovascular, and 576 IHD deaths occurred over a median follow-up period of 14.5 years. Among participants who achieved 1 or fewer cardiovascular health behaviours, age- and sex-standardized absolute risks were 14.8 deaths per 1000 person-years for all-cause mortality, 6.5 for cardiovascular mortality, and 3.7 for IHD mortality. Among those who met 6 or more metrics, corresponding risks were 5.4 for all-cause mortality, 1.5 for CVD mortality, and 1.1 for IHD mortality. When comparing participants who met 6 or more vs 1 or fewer cardiovascular health metrics, adjusted hazard ratios were 0.49 (95% CI, 0.33-0.74) for all-cause mortality, 0.24 (95% CI, 0.13-0.47) for CVD mortality, and 0.30 (95% CI, 0.13-0.68) for IHD mortality.
This study found that few people displayed optimal cardiovascular lifestyle behaviour, but that doing so was associated with a significantly lower risk of overall and cardiovascular mortality.
- Yang Q, Cogswell ME, Flanders D et al. Trends in Cardiovascular Health Metrics and Associations With All-Cause and CVD Mortality Among US Adults. JAMA 2012; 307(12): 1273-1283.