The Lancet has published the results of a meta-analysis of prospective studies of vascular mortality. This study found that "total cholesterol was positively associated with ischaemic heart disease (IHD) mortality in both middle and old age and at all blood pressure levels".
This conclusion comes as no surprise. The data covered almost 900,000 individuals without existing cardiovascular disease including nearly 12 million patient years. Total cholesterol and blood pressure data were available for these patients and HDL-C data were available for 150,000 patients.
The study found that a reduction in total cholesterol by 1mmol/L reduced the risk of IHD mortality by a half, a third and a sixth in 40-49, 50-69 and 70-89 year age groups. It is unclear how many patients were on cholesterol lowering treatments and this finding could be indicative of lower IHD mortality being associated with healthier lifestyles.
Action: The results of this study may be used to promote the "lower is better" message for total cholesterol. As with all observational data, these results should be used to generate a hypothesis for testing in a blinded and randomised controlled trial setting.