- Jun 20, 2015
Rauchhaus et al. [13,14] significantly contributed to the literature regarding cholesterol levels in HF. In a 2003 publication, this group analyzed two cohorts of HF patients (a derivation cohort in a metabolic study and a second independent group of HF patients) and also found that higher TC, LDL, and triglycerides (but not HDL) were significantly associated with improved survival. TC predicted mortality independent of other prognosticators, including cardiac cachexia, body mass index, peak oxygen consumption, and cytokine levels. LDL and triglyceride levels did not predict outcomes independent of TC. Receiver operator curve analysis identified a serum cholesterol of 201 mg/dL to be the best cutoff for mortality, similar to the 190 mg/dL described in the study by Horwich et al. .
Higher body mass index and higher blood pressure both predict better outcomes in patients with acute and chronic HF. Furthermore, reverse epidemiology with respect to risk factors such as body weight, cholesterol, and blood pressure, has been observed in other chronic disease populations, such as maintenance hemodialysis patients, rheumatoid arthritis, AIDS, and chronic obstructive pulmonary disease, and also in geriatric populations .[18,19•].
Potential Mechanisms for the Relationship Between Cholesterol and Mortality in Heart Failure
There are several potential mechanisms to explain the relationship between lipid levels and survival in HF. Low lipid levels may simply be markers for advanced disease and poor prognosis in HF. Low TC may be a reflection of malnutrition and cachexia, both of which are known to be associated with increased mortality in chronic HF [20,21]. Decreased lipid levels may also be a reflection of the systemic inflammatory activation characteristic of advanced HF. Both C-reactive protein (CRP) and cytokines such as tumor necrosis factor-α are upregulated in HF and predict poor prognosis in HF, and low lipid levels are closely associated with TNF and CRP [22,23].