Why is the incidence of ischaemic heart disease in Sweden increasing?: study of men born in 1913 and 1923.

The mortality from ischaemic heart disease (IHD) in the USA is falling, and this has been attributed to a changing life-style, with less smoking, more jogging, and less fat consumption, and to improved medical care. Similar changes in life-style are taking place in Sweden, but IHD mortality there is increasing. The rising incidence of IHD was also evident in two cohorts of 50-year-old Swedish men examined 10 years apart. Despite similar levels of traditional IHD risk factors, the incidence of IHD in the second cohort was almost double that in the first. Possible explanations for the increasing IHD mortality are an increasing prevalence of obesity in Swedish men, a longer "incubation" time during which the traditional risk factors have acted in the second cohort, or the appearance of unknown risk factors.