High LDL cholesterol levels associated with a 15% reduction in hospital death rates in heart attack patients

This study was published in the American Journal of Cardiology 2015 Mar 1;115(5):557-62

Study title and authors:
Relationship between serum low-density lipoprotein cholesterol and in-hospital mortality following acute myocardial infarction (the lipid paradox).

Reddy VS, Bui QT, Jacobs JR, Begelman SM, Miller DP, French WJ; Investigators of National Registry of Myocardial Infarction (NRMI) 4b–5.
F. Hoffmann-La Roche, Basel, Switzerland. Electronic address: reddy.vanessa@gene.com

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/25727079

This study investigated the association between cholesterol levels and in-hospital death rates in patients hospitalized for a heart attack. The study included 115,492 patients.

The study found:
(i) Patients with the highest LDL cholesterol levels had a 15% reduced risk of dying in hospital compared to patients with the lowest LDL cholesterol levels.
(ii) Patients with the lowest HDL cholesterol levels had a 20% increased risk of dying in hospital compared to patients with the highest HDL cholesterol levels.

Reddy concluded: "Lower LDL cholesterol levels associated with increased risk of in-hospital mortality".

Low levels of LDL cholesterol associated with a 65% increased risk of death in heart attack patients

This study was published in Critical Care Medicine 2015 Jun;43(6):1255-64

Study title and authors:
Lipid paradox in acute myocardial infarction-the association with 30-day in-hospital mortality.

Cheng KH, Chu CS, Lin TH, Lee KT, Sheu SH, Lai WT.
Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/25738856

The Killip classification (four classes - I to IV) is a system used in individuals with a heart attack. Individuals with a low Killip class are less likely to die within the first 30 days after their heart attack than individuals with a high Killip class.

This study was designed to clarify the relationship between cholesterol levels, Killip classification, and 30-day mortality in patients with a heart attack. The study included 724 heart attack patients.

The study found:
(a) Low-density lipoprotein (LDL) cholesterol and triglyceride levels were significantly lower in high-Killip (III + IV) patients compared with low-Killip (I + II) patients.
(b) Patients with low-density lipoprotein (LDL) cholesterol less than 62.5 mg/dL (1.6 mmol/L) had a 65% increased risk of death compared with patients with patients with low-density lipoprotein (LDL) cholesterol more than 62.5 mg/dL (1.6 mmol/L).
(c) Patients with triglyceride levels less than 110 mg/dL (1.24 mmol/L) had a 405% increased risk of death compared with patients with patients with triglyceride levels more than 110 mg/dL (1.24 mmol/L).
(d) Patients with a high-Killip classification and with with triglycerides less than 62.5 mg/dL (1.6 mmol/L) and low-density lipoprotein (LDL) cholesterol less than 110 mg/dL (1.24 mmol/L) had a 10.9-fold higher risk of death than patients with a low-Killip classification with triglycerides greater than 62.5 mg/dL (1.6 mmol/L) and low-density lipoprotein (LDL) cholesterol greater than 110 mg/dL (1.24 mmol/L).

Cheng concluded: "Low low-density lipoprotein (LDL) cholesterol, low triglycerides, and high Killip severity were associated with significantly higher 30-day in-hospital mortality in patients presenting with acute myocardial infarction".

Low cholesterol increases the risk of death by 75% after a heart attack

This study was published in the European Heart Journal 2001 Nov;22(22):2085-103

 

Study title and authors:

Assessment of absolute risk of death after myocardial infarction by use of multiple-risk-factor assessment equations: GISSI-Prevenzione mortality risk chart.

Marchioli R, Avanzini F, Barzi F, Chieffo C, Di Castelnuovo A, Franzosi MG, Geraci E, Maggioni AP, Marfisi RM, Mininni N, Nicolosi GL, Santini M, Schweiger C, Tavazzi L, Tognoni G, Valagussa F; GISSI-Prevenzione Investigators.

Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto miocardico (GISSI), Associazione Nazionale Medici Cardiologi Ospedalieri (ANMCO), Italy.

 

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/11686666

This study investigated the risk factors for death in patients after they had suffered a heart attack. The study included 11,324 men and women from the GISSI-Prevenzione trial who were followed for four years.

Regarding cholesterol levels, the study found that those with the lowest cholesterol, under 190 mg/dL (4.91 mmol/L), had a 75% increased risk of death compared to those with the highest cholesterol, over 245 mg/dL (6.3 mmol/L).