October 24, 2011 — New study results reveal several underlying causes of non-ischemic sudden cardiac death (SCD) — those not related to coronary artery disease (CAD) — including alcohol, obesity and myocardial fibrosis. The study, published in the October edition of HeartRhythm, the official journal of the Heart Rhythm Society (HRS), also reinforces CAD as one of the most prevalent causes of SCD in the general population. Furthermore, the results establish specific causes of non-ischemic SCD in different age groups, including people under the age of 40.
Between 1998 and 2007, postmortem examinations were performed at the department of forensic medicine of the University of Oulu in northern Finland. Causes of non-ischemic SCD were analyzed separately for people younger than 40 years, between 40 and 59 years, and older than 60 years. The study data was derived from a total of 2,661 SCD victims whose death occurred based upon a population of 467,190.
The autopsy rate of victims of sudden, unexpected death in Finland is relatively high, allowing for large-scale, non-biased analysis of SCD causes. The data were combined with the hospital patient records and questionnaires completed by relatives of SCD victims to improve diagnostic accuracy.
Concurrent with previous studies, CAD was the most prevalent cause of SCD (78.2 percent), while non-ischemic causes were found in 579 of the 2,661 victims (21.8 percent). Of the 579 victims analyzed, the most prevalent underlying causes of non-ischemic SCD in the people under 40 was fibrotic cardiomyopathy (CM, 28.3 percent), whereas alcoholic CM was the most common cause of death between 40-59 years of age (25.8 percent); CM related to obesity was the most common cause of death in people older than 60 (22.8 percent).
“As diagnosis and treatment methods evolve over time, it is important to always look for new ways to identify and attempt to reduce the occurrence of heart related deaths in the general population,” stated co-author Heikki V. Huikuri, M.D., department of internal medicine at University of Oulu. “The unique approach and novel findings of our study provides clinicians and patients with useful data about the potential causes of sudden cardiac death.”
Changes in lifestyle patterns, decreased physical activity and socioeconomic development have significantly changed in recent decades, ultimately affecting the incidence of SCD. Today, obesity has become a worldwide epidemic and is often recognized as a risk for cardiac diseases.
Additionally, it has been estimated that almost 4 percent of the global burden of disease is attributable to alcohol. As shown through this study, strategies to reduce obesity and alcohol intake may help lower the number of non-ischemic SCDs.
For more information: www.heartrhythmjournal.com