Abstract 46: Circulating Levels of Leptin Are Reduced in Patients with Sudden Cardiac Arrest at the Time of the Event
Introduction: In most published studies, elevated circulating levels of leptin have been associated with increased sympathetic tone and adverse cardiovascular outcomes. However, the specific association of leptin levels with sudden cardiac arrest (SCA) in the general population has not been evaluated.
Methods: In an ongoing, prospective, community-based study of SCA in Northwest US, we compared levels of plasma leptin in 109 adult cases of adjudicated SCA and 107 age-matched controls with coronary artery disease (100% male, age 62.6±11.4 vs. 62.6±11.4 y). Plasma was obtained from blood drawn at the time of arrest (cases) and at a routine visit (controls), and analyzed using Quantikine Immunoassay (CV <3.3%, normal range for healthy male controls 2.2-11.1 ng/ml). Leptin levels were log transformed and compared (T-test and Chi-square test) per quartiles (based on controls). Logistic regression was used to predict the adjusted odds of SCA case status associated with leptin levels (per increase in quartile).
Results: Leptin was significantly lower in SCA cases vs controls (median 2.0 [range 0.6 - 7.5] vs 8.5 [4.6 - 14.7] ng/ml, P<0.0001). Cases and controls did not differ regarding body mass index, smoking status, or prevalence of obesity (29.6±6.6 vs 29.2±5.3 and 40 vs 40%, both P>0.05) but controls were more likely to be on statin therapy (72 vs 44%, P<0.001). In a logistic regression model leptin was independently associated with decreased odds of SCA case status (OR/increased quartile of leptin 0.48 (95% CI 0.31 - 0.73, P=0.0006) also after adjusting for age, obesity, presence of coronary artery disease, smoking, and statin therapy (Table).
Conclusions: We observed an inverse relationship between circulating leptin levels and survival from SCA. These findings could represent an impaired sympathetic response to the acute SCA event but further investigation is needed to understand the mechanistic link between leptins and SCA.
- © 2012 by American Heart Association, Inc.