For a change, here's some good health news. Heart attacks in a segment of northern California are down 24% since 1999, and the most serious type of heart attacks are down 62%, according to a report published in the New England Journal of Medicine.

The decrease occurred among people insured by the Permanente Medical group. Kaiser Permanente, who conducted the study, is one of the country's largest not-for-profit health insurers.

The researchers attribute the decrease seen in this study to...increased use of medications to lower blood pressure and cholesterol...a decline in smoking [and] maintaining electronic medical records on all enrollees...

Particularly encouraging is the drop in the most serious type of heart attack, called STEMI (which refers to a particular electrocardiogram pattern, segment elevation type of acute myocardial infarction). These are the type of heart attacks most likely to cause death or permanent disability. Because of this decrease, heart disease is no longer the top cause of death among Permanente members (cancer is). Nationwide, heart disease has been the leading cause of death for decades.

Michael S. Lauer, M.D., the director of the division of cardiovascular sciences at the U.S. National Heart, Lung and Blood Institute, who was not involved in the study, says that there has been a consistent nationwide decrease in deaths from heart disease since the 1990s. This particular study just happens to be one of the larger ones and shows a larger than average decrease.

The researchers looked at over 18 million person-years of hospitalizations between 1999 and 2008. These included 46,086 hospitalizations for heart attack.

So much recent health news has focused on the unhealthy lifestyle and habits of many Americans. Why are heart attacks going down?

The researchers attribute the decrease seen in this study to several factors. Chief among them are increased use of medications to lower blood pressure and cholesterol. A decline in smoking has also helped. And they also think that Permanente's practice of maintaining electronic medical records on all enrollees has also been helpful. It allows doctors much easier access to all of a patient's medical information, which leads to improved recommendations and treatment.

Permanente's executive director says that if everyone in the nation received the same level of care as the study subjects, there would be 200,000 less deaths from heart attack and stroke nationwide.

Cynics might point out that this is a study conducted by an HMO that concludes that the HMO is doing a very good job, similar to what would be seen if everyone got to write their own end of year work evaluations. But as Lauer notes, the study results are consistent with known national trends.

Hopefully, people won't get the wrong message from the study. Heart attack incidence and severity are decreasing in spite of Americans eating more and exercising less, not because of them. Think of how much lower they might be if people adopted a healthier overall lifestyle.

The results of the study were published in the June 10, 2010 issue of the New England Journal of Medicine.