leptin and Death--Sudden--Cardiac

Obstructive sleep apnea (OSA) is a chronic disease characterized by repetitive partial or complete closure of the upper airway during sleep. OSA tends to be associated with components of metabolic syndrome sharing a common ground of metabolic changes with metabolic syndrome itself. Recent studies showed that subjects with OSA were 6-9 times more likely to have metabolic syndrome than subjects without OSA. Intermittent hypoxia and sleep fragmentation in OSA can initiate intermediary mechanisms (oxidative stress, neurohumoral changes, inflammation) leading to the components of metabolic syndrome. OSA has been suggested to be a novel risk factor, inside the metabolic syndrome, contributing to increased cardiovascular risk. Several studies report that continuous positive airway pressure (CPAP) treatment can reverse pathophysiological changes in OSA, increasing insulin sensitivity and reducing blood pressure. Recent evidences show that CPAP treatment reduces the risk of cardiovascular events and mortality in subjects with OSA. Some subjects with metabolic syndrome can be affected by undiagnosed OSA: CPAP treatment could significantly reduce cardiovascular risk in this subgroup of patients.

Topics: Age Factors; Aged; Blood Glucose; Cardiovascular Diseases; Clinical Trials as Topic; Continuous Positive Airway Pressure; Death, Sudden, Cardiac; Diabetes Mellitus, Type 2; Glucose Tolerance Test; Humans; Hypertension; Insulin Resistance; Leptin; MEDLINE; Metabolic Syndrome; Obesity; Randomized Controlled Trials as Topic; Risk Factors; Sleep Apnea, Obstructive; Stroke

Leptin is an adipose tissue-derived hormone associated with cardiovascular risk factors. We examined whether leptin predicts major adverse cardiac events (MACE) in coronary artery disease (CAD) patients.. Fasting plasma leptin levels were measured in 1327 male and 619 female CAD patients. The patients were followed up for two years. The primary endpoint (MACE) was the composite of a hospitalisation for congestive heart failure (CHF) or a cardiac death. The secondary endpoint was the composite of an acute coronary syndrome (ACS) or a stroke.. In regression analysis including established risk variables, high leptin levels were associated with a significantly increased risk of MACE (HR 3.37; 95%CI 1.64-6.90; p = 0.001) and ACS or stroke (HR 1.95; 95%CI 1.29-2.96; p = 0.002). Adding leptin to the risk model for MACE increased the C-index from 0.78 (95%CI 0.71-0.85) to 0.81 (0.74-0.88) and improved classification (NRI 0.36; 95%CI 0.13-0.60; p = 0.002) and discrimination of the patients (IDI 0.016; 95%CI 0.001-0.030; p = 0.031).. High plasma leptin levels predict short-term occurrence of CHF or cardiac death and ACS or stroke in patients with CAD independently of established risk factors. The possible harmful effects of leptin should be thoroughly investigated. Key messages Leptin is a peptide hormone secreted mainly by adipose tissue. It has been associated with several cardiovascular risk factors. High leptin levels predict the short-term occurrence of congestive heart failure or cardiac death and ACS or stroke in patients with CAD independently of established risk factors. The possible detrimental effects of leptin on the cardiovascular system should be thoroughly investigated.

Topics: Acute Coronary Syndrome; Aged; Biomarkers; Coronary Artery Disease; Death, Sudden, Cardiac; Fasting; Female; Follow-Up Studies; Heart Failure; Hospitalization; Humans; Leptin; Male; Middle Aged; Predictive Value of Tests; Risk Assessment; Risk Factors; Stroke