Achieving LDL cholesterol target levels <1.81 mmol/L may provide extra cardiovascular protection in patients at high risk: Exploratory analysis of the Standard Versus Intensive Statin Therapy for Patients with Hypercholesterolaemia and Diabetic Retinopathy study.

AIMS

To assess the benefits of intensive statin therapy on reducing cardiovascular (CV) events in patients with type 2 diabetes complicated with hyperlipidaemia and retinopathy in a primary prevention setting in Japan. In the intension-to-treat population, intensive therapy [targeting LDL cholesterol <1.81 mmol/L (<70 mg/dL)] was no more effective than standard therapy [LDL cholesterol ≥2.59 to <3.10 mmol/L (≥100 to <120 mg/dL)]; however, after 3 years, the intergroup difference in LDL cholesterol was only 0.72 mmol/L (27.7 mg/dL), and targeted levels were achieved in <50% of patients. We hypothesized that the intergroup difference in CV events would have been statistically significant if more patients had been successfully treated to target.

MATERIALS AND METHODS

This exploratory post hoc analysis focused on intergroup data from patients who achieved their target LDL cholesterol levels. The primary endpoint was the composite incidence of CV events. A Cox proportional hazards model was used to estimate hazard ratios (HRs) for incidence of the primary endpoint in patients who achieved target LDL cholesterol levels in each group.

RESULTS

Data were analysed from 1909 patients (intensive: 703; standard: 1206) who achieved target LDL cholesterol levels. LDL cholesterol at 36 months was 1.54 ± 0.30 mmol/L (59.7 ± 11.6 mg/dL) in the intensive group and 2.77 ± 0.46 mmol/L (107.1 ± 17.8 mg/dL) in the standard group (P < 0.05). After adjusting for baseline prognostic factors, the composite incidence of CV events or deaths associated with CV events was significantly lower in the intensive than the standard group (HR 0.48; 95% confidence interval 0.28-0.82; P = 0.007).

CONCLUSIONS

This post hoc analysis suggests that achieving LDL cholesterol target levels <1.81 mmol/L may more effectively reduce CV events than achieving target levels ≥2.59 to <3.10 mmol/L in patients with hypercholesterolaemia and diabetic retinopathy.