Using more recent data, we updated our analysis of Death and the Human Environment published in 2001 on competition between cancers and cardiovascular conditions as the leading cause of death in the US. We revisited the paper’s Figure 8, which projected cancers overtaking heart diseases about the year 2015.
In the past decade the fraction of deaths from cardiovascular conditions has decreased significantly, from 42% in 1993 to 34 % in 2006, as forecast. However, unexpectedly, the fraction of deaths resulting from malignant neoplasms has remained level (~23%). Fitting logistic curves to the updated dataset, we deduce that if the trends remain stable, the crossover is now likely deferred to about 2025.
Declining rates of smoking are likely a major contributer to the steady decline in cardiovascular deaths since 1965 and the more recent flattening of cancer-deaths. For example, epidemiologists associated with the American Cancer Society recently reported a 30% decline in age-standardardized cancer death rates since 1990, resulting “mostly from reductions in tobacco use, increased screening allowing early detection of several cancers, and modest to large improvements in treatment for specific cancers” (Jemal et al PLoS ONE, March 2010). The temporal trends in cardiovascular and cancer deaths may reflect differential effects of stopping smoking, as tobacco cessation has a large, relatively immediate benefit for cardiovascular disease, whereas reductions in cancer are more modest and delayed.