Smoking poses less risk for dyslipidemia in very elderly
MedWire News: Smoking does not have a detrimental effect on lipid profiles in individuals aged 90 years or more, report Chinese researchers.
In fact, smokers aged 90 years or over were found to have lower levels of total cholesterol (TC) and a lower prevalence of hypercholesterolemia than nonsmokers of the same age, in a study conducted by Dong Bi-Rong (Sichuan University) and colleagues.
"Our results showed that the relationship between smoking habits and TC in long-lived subjects was different than in the general population," writes the team in Lipids in Health and Disease.
In the general population, evidence has shown that smoking leads to increased TC levels and that smoking and hypercholesterolemia increase the risk for cardiovascular disease, dementia, depression, and disability.
In their analysis of available data for 661 participants (aged 90 years or more) from the Project of Longevity and Aging in Doujiangyan, the team found that 401 individuals had a history of smoking (60.7%), 128 (19.3%) of whom had ceased the habit and 273 (41.3%) of whom were current smokers.
The study revealed that current smokers had a significantly lower mean level of TC than nonsmokers, at 4.05 mmol/L versus 4.21 mmol/L.
The smokers also had a significantly lower mean prevalence of hypercholesterolemia than nonsmokers, at 9.62% versus 15.13%.
On the other hand, mean levels of triglycerides, low-density lipoprotein, and high-density lipoprotein were similar between the two groups.
Furthermore, multivariate analysis showed that smokers were not at any significantly greater risk for abnormal lipid profiles than nonsmokers were.
"The high mortality in the elderly could remove those with hypercholesterolemia, which was caused by current smoking," suggest the authors.
The possibility that this could have led to a lower TC level in current smokers, compared with nonsmokers, is a "reasonable inference which should be further confirmed using prospective cohort study," add Bi-Rong et al.
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By Sally Robertson, MedWire News Reporter