Here is more evidence that the optimum level of cholesterol is much higher then the so-called experts would have you believe.
–W Greene, D.C.
DocGuideReview
Low Cholesterol May Increase Mortality Risk In Over 70s
A DGReview of :”Cholesterol and all-cause mortality in elderly people from the Honolulu Heart Program: a cohort study”
Lancet
08/02/2001
By Harvey McConnell
Low cholesterol rates in people over the age of 70 may increase and not decrease their mortality risks.
“Our data accord with previous findings of increased mortality in elderly people with low serum cholesterol, and show, for the first time, that long-term persistence of low cholesterol concentration actually increases risk of death,” declares Dr Irwin Schatz and colleagues at University of Hawaii at Manoa, John A. Bums School of Medicine, Honolulu, Hawaii.
“These data cast doubt on the scientific justification for lowering cholesterol to very low concentrations (less than 4.65 mmol/L) in elderly people.”
Dr Schatz and colleagues point out:” High concentration of total serum cholesterol is known to be directly related to mortality in individuals aged younger than 65 years. Previous clinical trials have not had large numbers of patients aged older than 70 years, and researchers have been unable to conclusively show this relation in elderly people.”
In a longitudinal population study, part of the Honolulu Heart Program, a large epidemiological study of cardiovascular disease, the clinicians studied fat and blood cholesterol concentrations of 3,572 Japanese/American men who were aged 71-93 years in the????ly 1990s. They compared changes in these concentrations over 20 years with all-cause mortality using three different Cox proportional hazards models.
Overall, average cholesterol concentrations decreased with increasing age of individuals in the study population.
Individuals were divided into four quartiles according to blood cholesterol concentrations: 1st quartile 2.09-4.32 mmol/L; 2nd quartile 4.33-4.86 mmol/L; third quartile 4.87-5.43mmol/L; fourth quartile 5.44-9.88 mmol/L.
Lower cholesterol concentration was associated with increased death rates; age-adjusted mortality rates were 68.3, 48.9, 41.1, and 43.3 per 1, 000 population per year for the first to fourth quartiles of cholesterol concentrations, respectively. Men in quartiles 2, 3, and 4 had reduced death-rates of 28 percent, 40 percent , and 35 percent respectively compared with men in the first (lowest cholesterol concentration) quartile.
Dr Schatz and colleague declare: “We have been unable to explain our results.” But they speculate on the meanings.
Based on their data “the earlier that patients start to have lower cholesterol concentrations, the greater the risk of death. Cholesterol metabolism and homoeostatic mechanisms might differ in the very old (75 years), and little information is available about cholesterol-mortality relations in this age group.”
Perhaps the data indicate a selective mortality; “those individuals who are susceptible to biological effects of high serum cholesterol die before they reach age 75 years. The individuals who are left would be a select group with lower cholesterol and whose genetic makeup or other factors protect them from the effects of higher cholesterol concentrations.”
To some degree, the clinicians continue, the Honolulu Heart Program data support this hypotheses as there are few individuals with truly high concentrations of cholesterol remaining in this population.
Dr Schatz and colleagues, in conclusion, raise two questions: “First, is there a difference in biological effect from a permanent, untreated, intrinsically low concentration of cholesterol when compared with the effect in those who have a dietary or pharmacologically induced reduction of cholesterol? As far as we are aware, this issue has not been addressed scientifically.
“Second, in view of our data, and those of others, is there scientific justification for attempts to lower cholesterol to concentrations below 4.65 mmol/L in elderly people” We believe that until more information about these complex relations is available, prudence dictates a more conservative approach in this age group.”
Lancet 2001; 358: 351-5. “Cholesterol and all-cause mortality in elderly people from the Honolulu Heart Program: a cohort study”
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