As noted, assessment of compliance [2] is important for drug evaluation and study sample size must be sufficient for statistical power. However, the retrospective nature of this study made it difficult to assess or guarantee compliance. We assumed that all patients would be equally compliant regardless of treatment regimen.

Switching from atorvastatin to other statins rather than increasing the dose of atorvastatin when target levels of low density lipoprotein cholesterol (LDL-C) are not reached remains an interesting possibility. In normal practice, increasing the dose is more common than switching to other statins unless significant side effects are observed, because atrovastatin is one of the most powerful statins available for reducing LDL-C levels [3,4].

As to the comment regarding how to interpret poor response to statin therapy in patients with high body mass index (BMI). We found that BMI is significantly correlated with baseline LDL-C levels. Patients with large fat mass may harbor large cholesterol pools in their bodies. Thus, to reduce the levels of LDL-C in these patients, higher amounts of statin or combination regimens with other agents such as ezetimibe [5,6] may be required.