Carotid intima-media thickness: a target or a marker?

Evidence-based medicine requires us to use pharmacological agents that have been tested and that have been showed to reduce the disease in that particular group of affected patients. The choice of the efficacy endpoint is one of the most controversial issues in designing the trials. To reduce the high economic costs resulting by the large-scale trials design and implementation, the substitution of the primary endpoints with a surrogate one, is an optimal opportunity. Carotid intima-media thickness is considered an excellent predictor of cardiovascular events, and it is also seen as a perfect model of surrogate endpoint for pharmacological studies. However, the results from studies using it as a surrogate endpoints could lead to erroneous conclusions and could lead marketing of products with limited or doubt effectiveness on cardiovascular prevention. Studies showed that many interventions targeting the Carotid intima-media thickness not impact the final clinical endpoints of interest, whereas low-density lipoprotein cholesterol level is an excellent biomarker because it can predict the cardiovascular outcomes and interventions therapy can efficaciously reduce it.