TUESDAY, Oct. 4 (HealthDay News) -- Obesity and alcohol consumption are among the leading causes of sudden cardiac death not caused by coronary artery disease, a new study finds.

Researchers analyzed data from autopsies of almost 2,700 people in Finland who died of sudden cardiac death -- in which the heart abruptly stops beating and death occurs rapidly -- between 1998 and 2007, along with the patients' hospital records and questionnaires completed by their relatives.

Coronary artery disease was deemed to be the cause of death in 78 percent of cases, while causes unrelated to coronary artery disease were found in about 22 percent, the University of Oulu researchers said in a journal news release.

Coronary artery disease is a narrowing of the blood vessels that bring blood and oxygen to the heart, caused by a buildup of plaque on the arterial walls.

Of the deaths not related to coronary artery disease, the most common underlying cause of death in people younger than 40 was fibrotic cardiomyopathy (28.3 percent). Cardiomyopathy is a weakening and enlargement of the heart muscle that makes it harder for it to pump blood.

Alcohol consumption was the most common cause (about 26 percent) in people ages 40 to 59, and obesity was the most common cause (almost 23 percent) in people older than 60.

The findings reinforce coronary artery disease as one of the most common causes of sudden cardiac death, but also identify other causes of sudden death in different age groups.

The study was published Oct. 3 in the October issue of the journal HeartRhythm.

More information

The U.S. National Heart, Lung, and Blood Institute has more about sudden cardiac death.