Thursday, April 16, 2009

LDL-C REDUCTION AND STROKES

The May 2009 ( it is only April 2009 now ) issue of the Lancet, carries an article by French researchers, Drs P Amarenco and J Labreuche. They did a meta-analysis of 24 large RCT on LDL-C reduction with statins and the incidence of strokes. The meta-analysis involves 165,000 patients ( a very large number ). The trials included in this meta-analysis included many of the large ones like JUPITER, SEARCH, SPARCL, TNT, PROVE-IT, HPS, LIPID, IDEAL and CARE ( almost all the important ones ). They found that LDL-C reduction reduced ischemic strokes. For every 38mg/dl LDL-C reduction, there was a 21% stroke reduction, more so in the high risk population.
This study is fascinating because we are often taught that the cerebral circulation is quite different from the coronary circulation and hypertension was an important cause of strokes. The result of this large meta-analysis would suggest that strokes are due to plaque eruption or erosions from arterosclerotic plaques, and that we may also have to think of hard and soft plaques, as we do in coronary artery disease. I would rather think that this is a meta-analysis and so we must not read too much into it. We have a statistical observation which we have to explain, but may not suggest a causal relationship. It is also important to note that previous attempts to correlate cholesterol levels with incidence of strokes, were rather inconsistent.
Be that as it may, I suppose I do appreciate that reducing LDL-C for my heart may also help my head vessels. And if there is no important side effects, maybe a reasonable thing to do, especially in a high risk population like T2DM, hypertension, the elderly population, patients with previous strokes and patients with previous TIA.
As a small point, I also note that I can now buy books printed in 2009 from my favourate bookshop and also read medical journals of May 2009 in April 2009.

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