Low cholesterol levels are associated with higher death rates

This study was published in the Scandinavian Journal of Primary Health Care 2013 Sep;31(3):172-80

Study title and authors:
Association of lipoprotein levels with mortality in subjects aged 50 + without previous diabetes or cardiovascular disease: a population-based register study.

Bathum L, Depont Christensen R, Engers Pedersen L, Lyngsie Pedersen P, Larsen J, Nexøe J.
Department of Clinical Biochemistry, Slagelse Hospital, Region Zealand, Denmark. lbat@regionsjaelland.dk

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/23941088

This study aimed to investigate the association of cholesterol levels with death rates in men and women free from diabetes and cardiovascular disease. The study included 118,160 subjects, aged 50 and over, and lasted for nine years.

The study found:
(a) In men aged 50 - 60: Those with cholesterol levels between 6 - 7.99 mmol/L (232 - 309 mg/dL) had a 32% reduced risk of death compared to those with cholesterol levels below 5 mmol/L (193 mg/dL).
(b) In women aged 50 - 60: Those with cholesterol levels between 6 - 7.99 mmol/L (232 - 309 mg/dL) had a 29% reduced risk of death compared to those with cholesterol levels below 5 mmol/L (193 mg/dL).
(c) In men aged 60 - 70: Those with cholesterol levels between 6 - 7.99 mmol/L (232 - 309 mg/dL) had a 33% reduced risk of death compared to those with cholesterol levels below 5 mmol/L (193 mg/dL).
(d) In women aged 60 - 70: Those with cholesterol levels between 6 - 7.99 mmol/L (232 - 309 mg/dL) had a 41% reduced risk of death compared to those with cholesterol levels below 5 mmol/L (193 mg/dL).
(e) In men aged over 70: Those with cholesterol levels between 6 - 7.99 mmol/L (232 - 309 mg/dL) had a 38% reduced risk of death compared to those with cholesterol levels below 5 mmol/L (193 mg/dL).
(f) In women aged over 70: Those with cholesterol levels between 6 - 7.99 mmol/L (232 - 309 mg/dL) had a 41% reduced risk of death compared to those with cholesterol levels below 5 mmol/L (193 mg/dL).
(g) In both men and women between the ages of 50 -70: Cholesterol levels over 8 mmol/L (310 mg/dL) had no impact on death rates.
(g) (i) In men aged over 70: Those with cholesterol levels over 8 mmol/L (310 mg/dL) had a 33% reduced risk of death compared to those with cholesterol levels below 5 mmol/L (193 mg/dL).
(g) (ii) In women aged over 70: Those with cholesterol levels over 8 mmol/L (310 mg/dL) had a 41% reduced risk of death compared to those with cholesterol levels below 5 mmol/L (193 mg/dL).
(h) In men aged 50 - 60: Those with low density lipoprotein (LDL) cholesterol levels over 4 mmol/L (154 mg/dL) had a 56% reduced risk of death compared to those with low density lipoprotein (LDL) cholesterol levels below 2.5 mmol/L (96 mg/dL).
(i) In women aged 50 - 60: Those with low density lipoprotein (LDL) cholesterol levels over 4 mmol/L (154 mg/dL) had a 31% reduced risk of death compared to those with low density lipoprotein (LDL) cholesterol levels below 2.5 mmol/L (96 mg/dL).
(j) In men aged 60 - 70: Those with low density lipoprotein (LDL) cholesterol levels over 4 mmol/L (154 mg/dL) had a 55% reduced risk of death compared to those with low density lipoprotein (LDL) cholesterol levels below 2.5 mmol/L (96 mg/dL).
(k) In women aged 60 - 70: Those with low density lipoprotein (LDL) cholesterol levels over 4 mmol/L (154 mg/dL) had a 53% reduced risk of death compared to those with low density lipoprotein (LDL) cholesterol levels below 2.5 mmol/L (96 mg/dL).
(l) In men aged over 70: Those with low density lipoprotein (LDL) cholesterol levels over 4 mmol/L (154 mg/dL) had a 37% reduced risk of death compared to those with low density lipoprotein (LDL) cholesterol levels below 2.5 mmol/L (96 mg/dL).
(m) In women aged over 70: Those with low density lipoprotein (LDL) cholesterol levels over 4 mmol/L (154 mg/dL) had a 40% reduced risk of death compared to those with low density lipoprotein (LDL) cholesterol levels below 2.5 mmol/L (96 mg/dL).
(n) In men aged 50 - 60: Those with high density lipoprotein (HDL) cholesterol levels between 1.5 - 1.9 mmol/L (58 - 76 mg/dL) had a 36% reduced risk of death compared to those with high density lipoprotein (HDL) cholesterol levels below 1.0 mmol/L (38 mg/dL).
(o) In women aged 50 - 60: Those with high density lipoprotein (HDL) cholesterol levels between 1.5 - 1.9 mmol/L (58 - 76 mg/dL) had a 60% reduced risk of death compared to those with high density lipoprotein (HDL) cholesterol levels below 1.0 mmol/L (38 mg/dL).
(p) In men aged 60 - 70: Those with high density lipoprotein (HDL) cholesterol levels between 1.5 - 1.9 mmol/L (58 - 76 mg/dL) had a 43% reduced risk of death compared to those with high density lipoprotein (HDL) cholesterol levels below 1.0 mmol/L (38 mg/dL).
(q) In women aged 60 - 70: Those with high density lipoprotein (HDL) cholesterol levels between 1.5 - 1.9 mmol/L (58 - 76 mg/dL) had a 65% reduced risk of death compared to those with high density lipoprotein (HDL) cholesterol levels below 1.0 mmol/L (38 mg/dL).
(r) In men aged over 70: Those with high density lipoprotein (HDL) cholesterol levels between 1.5 - 1.9 mmol/L (58 - 76 mg/dL) had a 35% reduced risk of death compared to those with high density lipoprotein (HDL) cholesterol levels below 1.0 mmol/L (38 mg/dL).
(s) In women aged over 70: Those with high density lipoprotein (HDL) cholesterol levels between 1.5 - 1.9 mmol/L (58 - 76 mg/dL) had a 46% reduced risk of death compared to those with high density lipoprotein (HDL) cholesterol levels below 1.0 mmol/L (38 mg/dL).

This study shows that low cholesterol levels, low LDL and HDL cholesterol levels are associated with higher death rates.