Temporal trends in coronary heart disease mortality and sudden cardiac death from 1950 to 1999: the Framingham Heart Study.
Level 3 - non-randomized controlled study
Longitudinal prospective cohort study analyzing temporal trends over 50 years
PubMed 15262842 · doi:10.1161/01.CIR.0000136993.34344.41
What was done
Investigators evaluated temporal trends in sudden cardiac death (SCD) and nonsudden coronary heart disease (CHD) mortality in the Framingham Heart Study original and offspring cohorts between 1950 and 1999. SCD was defined as death attributed to CHD with symptoms lasting less than 1 hour, adjudicated by a physician panel. Log-linear Poisson regression was used to estimate age- and gender-adjusted risk ratios.
What was found
Across the study period, there were 811 CHD deaths (453 nonsudden CHD deaths and 358 SCDs). Antecedent CHD was absent in 20% (91/453) of nonsudden CHD deaths and 48% (173/358) of SCDs. Comparing 1950–1969 with 1990–1999: - Overall CHD death rates decreased by 59% (95% CI 47% to 68%, P(trend) < 0.001). - Nonsudden CHD death decreased by 64% (95% CI 50% to 74%, P(trend) < 0.001). - SCD rates decreased by 49% (95% CI 28% to 64%, P(trend) < 0.001). These trends were observed across men and women, subjects with and without a prior history of CHD, and smokers and nonsmokers.
Why it matters
These findings demonstrate that 50-year declines in cardiovascular mortality reflect substantial reductions in both sudden and nonsudden cardiac deaths across primary and secondary prevention settings.
Limits
The total participant denominator is not specified in the abstract. The study is restricted to the Framingham cohorts, which are geographically and demographically homogeneous. Observational trend data cannot isolate the relative impacts of specific medical therapies versus lifestyle changes.
Cited by
- supports Cardiovascular disease mortality has dropped from approximately half of all deaths in the 1950s to approximately one-third of deaths currently.