It's been suggested that intensive statin therapy is associated with reduced risk for cardiovascular events. But, LDL cholesterol levels in these patients could be well below the target levels of 100 mg/dL or even the 70 mg/dL level suggested in recent guidelines. In this retrospective analysis, investigators analyzed outcomes in more than 1800 patients with acute coronary syndrome who were randomized to intensive lipid-lowering therapy with atorvastatin in the PROVE IT study. For the current analysis, patients were stratified by LDL levels at 4 months (>100, 80–100, 60–80, 40–60, and <40 mg/dL).
After 4 months of therapy, most subjects had LDL levels of 60–80 mg/dL (31% of patients) or 40–60 mg/dL (34%), but 11% had levels of 40 mg/dL or lower. Patients with lower LDL levels at 4 months were more likely to be older, male, or diabetic, and to have lower baseline LDL levels. No significant differences were noted in liver, muscle, or retinal abnormalities between patients with lower LDL levels and those with higher levels. The lower-LDL patients had fewer cardiac events, but no significant differences were reported in overall mortality.
This retrospective analysis suggests that intensive lipid-lowering therapy to achieve very low LDL levels is safe and effective. The authors suggest that, based on these data, we need not reduce statin doses when intensive therapy results in LDL levels well below guideline recommendations. However, it remains to be determined whether such very low LDL levels should be our target, and whether adverse effects of very low levels could emerge during longer-term follow-up.
Reference:
Wiviott SD et al. Can low-density lipoprotein be too low? The safety and efficacy of achieving very low low-density lipoprotein with intensive statin therapy: A PROVE IT-TIMI 22 substudy. J Am Coll Cardiol 2005 Oct 18; 46:1411-6.