Heart attack deaths decrease

(18.03.2011) 

Life was hard in occupied Norway during WWII, but the occupation had one surprising result: deaths from heart attacks dropped precipitously, because Norwegians ate less fat, smoked less and were more physically active.

Now, in the last half of the 20th century, Norway has seen a similar precipitous drop in heart attack deaths, but this time due to focused prevention programmes and improved treatment, reports a researcher at the Norwegian University of Science and Technology (NTNU).

Writing in the latest issue of the Journal of the Norwegian Medical Association, NTNU Professor Kaare Harald Bønaa notes that the percentage of deaths due to heart disease and cardiovascular disease dropped from 50 per cent in 1975 to 33 per cent in 2009 in Norway, and that deaths from heart attacks alone dropped to levels that were last seen during WWII. Bønaa is a professor of heart and cardiovascular disease epidemiology at NTNU, and is chief physician in charge in intervention cardiology at St Olavs Hospital in Trondheim.

Risk factors down, treatment improved
"Overall, there is solid evidence that the decline in mortality from heart attacks is due to changes in risk factors and treatment," Bønaa writes.

There are many reasons that explain the numbers, Bønaa says. Reductions in cholesterol levels, smoking and high blood pressure can explain between 50 and 75 percent of the reduced mortality, he says. 

The remainder is explained by better medical treatment, where drugs have had the greatest impact, whether statins, beta blockers or other medicines. 



Bønaa believes changes in cholesterol levels and smoking habits have contributed significantly to reducing the Norwegian heart attack epidemic. 

"From the 1970s, cholesterol levels have been reduced by about 10 percent, while the proportion of smokers has been halved," he says. 



More women die


But Bønaa warns that the battle against heart disease has not been won. In one study in Tromsø, in northern Norway, the incidence of a first time heart attack in young- and middle-aged women actually increased over the period from 1974 to 2004, while in the same age groups of men, it decreased.

Another surprising trend in Norway is that more women than men in the 16-74 age group smoke, which has resulted in an increased incidence of lung cancer and COPD in this age group of women, as well as an increase in heart attack risks.

Increases elsewhere, and an ageing populace
Elsewhere, lesser developed countries are actually seeing a massive increase in cardiovascular disease, while in Norway, the reduction in risk has leveled off, and 70 percent of the population still has cholesterol levels that are too high. 



And, Bønaa adds, as the Norwegian population ages, the medical community must anticipate an increased number of heart attacks in the older segments of the population and an increasing number of patients with chronic heart disease.

Journal of the Norwegian Medical Association cover March 2011