Abstract 2632: Stroke Protection Is Largely Related To Cholesterol-lowering In Lipid-lowering Intervention Trials: A Meta-analysis And Meta-regression
Background: In clinical trials, statins reduce the incidence of strokes. It has been proposed that such effect is independent of cholesterol lowering and best explained by alternative mechanisms. We tested whether the effects of statins on stroke is qualitatively similar to that of other cholesterol-lowering interventions, and explained by cholesterol lowering.
Methods: We reviewed the literature of randomized lipid-lowering trials reporting the stroke incidence, for a total of 176,974 patients investigated and a cumulative 627,117 patients/year exposure. Strokes incidence was related to treatments tested in the trials, and a meta-regression related the extent of stroke reduction as a function of the reduction in total cholesterol.
Results: The odds ratio and 95% confidence interval (95% CI) for the total incidence of stroke in the actively-treated group compared with controls were 0.86 (0.81– 0.91, p<0.001). Statins decreased the risk of total stroke significantly (0.83, 0.78 – 0.89, p<0.001). The benefit of non-statin interventions on total stroke was small and not statistically significant (OR 0.95, 95% CI 0.85–1.08, p=N.S.). In the meta-regression, however, we found a significant relationship between the percent reduction of total cholesterol obtained in both statin and non-statin trials and the percent reduction of the relative risk of total stroke (p=0.0471). Neither statins nor other cholesterol-lowering interventions reduced the risk of fatal stroke.
Conclusions: Among lipid-lowering interventions, statins are effective in decreasing the risk of total stroke, but their benefit appears associated with the extent of reduction of blood cholesterol, and is in line with their greater cholesterol-lowering potency compared with non-statin interventions.