Omega-3s May Counter Sudden Cardiac Death in Dialysis Patients
Heart attack: Omega-3 protect against heart attacks in dialysis patients
Sudden cardiac death, the leading cause of death in patients undergoing renal dialysis, can be prevented by Omega-3. High levels of the polyunsaturated fatty acids abundant in fish oil are associated with a strong reduction in the risk of unexpected cardiac death.
This was discovered by researchers at the Indiana School of Medicine, in collaboration with researchers from Massachusetts General Hospital (USA). The study was published in the journal Kidney International.
Action of Omega-3 in hemodialysis patients
Hemodialysis is a method used to treat kidney failure, during which the patient’s blood is extracted, filtered through a semipermeable membrane, and then reintroduced into the vein. Patients undergoing this treatment are particularly vulnerable to sudden cardiac death, with an annual incidence of 6-7%, especially in the first months of therapy, for reasons not yet fully understood. Although no other studies have been published on the relationship between blood Omega-3 concentration and sudden cardiac death risk in dialysis patients, it has been demonstrated in clinical and experimental models that these fatty acids have a protective effect against ventricular arrhythmias. Other studies show that in America, the consumption of Omega-3 by dialysis patients is generally very low.
The concentration of Omega-3 is associated with the risk of sudden cardiac death
During the case-control study, conducted by Professor Alon Friedmann, medical doctor, data were collected from patients who had started dialysis at one of the 1000 centers involved in the project, between June 2004 and July 2005. The Omega-3 levels of 100 patients who died during the first year of dialysis were then compared with those of 300 survivors. Results showed that in patients who died of sudden cardiac death, concentrations of saturated and monounsaturated fatty acids were high, while those of polyunsaturated Omega-3 fatty acids, such as DHA (docosahexaenoic acid), were significantly lower than in survivors. Data also showed that Omega-3 levels linked to serum phospholipids were inversely associated with sudden cardiac death events during the first year of dialysis and particularly during the first months, when risk is highest. In particular, researchers estimated that patients with higher Omega-3 levels had up to an 80% lower probability of dying compared to those with the lowest levels.
Omega-3 in hemodialysis, effects to be further investigated
These results represent a first step toward identifying a possible treatment to prevent cardiac death in patients undergoing dialysis. Furthermore, this study could have important implications for the type of diet dialysis patients should follow, given that Omega-3 are abundant in certain foods such as fish oil.
Source: Allon N. Friedman, Zhangsheng Yu, Rebeka Tabbey, Cheryl Denski, Hector Tamez, Julia Wenger, Ravi Thadhani, Yong Li, and Bruce Watkins “Inverse relationship between long chain n-3 fatty acids and risk of sudden cardiac death in patients starting hemodialysis” Kidney Int. 2013 June ; 83(6): 1130–1135. doi:10.1038/ki.2013.4.
