Improved treatments lead to improved CHD mortality

Although rates of coronary heart disease (CHD) mortality have declined substantially over the past three decades, the exact reasons for this are not yet clear. Identifying the factors associated with this improvement is vital for setting future healthcare policy. Diet, lifestyle, risk factors and treatment uptake are all important, but these change rapidly and have not been studied in the past decade.

This prospective Canadian study, which was carried out in Ontario between 1994 and 2005, aimed to determine what proportion of the decline was due to temporal trends in CHD risk factors and improvements in cardiovascular treatments. An updated version of the validated IMPACT model was used, which takes into account population size, CHD mortality, risk factors and changes in the uptake of treatments. The primary outcome measure was the number of deaths prevented or delayed in 2005, while secondary outcomes included trends in risk factors and improvements in medical treatments.

Over the 10-year period studied, the age-adjusted CHD mortality rate in Ontario decreased by 35% from 191 to 125 deaths per 100 000 inhabitants, …