Risk factor levels, risk factor combinations, and residual coronary risk: population-based estimates for secondary prevention patients using statins

BACKGROUND: Population-based risk factor combinations and residual risks for coronary heart disease (CHD) patients on statins were assessed in order to bridge the gap between knowledge on relative effects from clinical trials and absolute risk from real-world practice. DESIGN: Population-based, retrospective 1-year cross-sectional primary care study in CHD patients (ICD-10 I20-I25) on ongoing statin monotherapy in Germany in 2007 (MediPlus database, IMS Health). METHODS: Prevalence charts for 384 risk factor combinations were constructed. Population-averaged residual risks were estimated using the Framingham secondary prevention algorithm and generalized estimating equations accounting for repeated measurements within patients. RESULTS: 13,256 CHD patients in 332 practices were eligible for the study (7791 men, 5465 women, 32.6% with diabetes mellitus, 82.5% on simvastatin at a mean effective dose of 26.7 mg/d). The overall residual 10-year coronary risk was projected at 35.1% (robust 95% CI 34.8-35.4). In 83.6% of patients this risk was ≥20% and in 36.5% of patients the risk was ≥40%. An increase in tablet strength to 40 mg (fluvastatin 80 mg) and in exposure to 40 mg/d (fluvastatin 80 mg/d) would be expected to reduce the predicted residual 10-year coronary risk to 34.1% and 33.8%, respectively. CONCLUSION: Even when receiving high-dose statin monotherapy, the typical CHD patient in Germany is projected to be exposed to a residual coronary risk that is substantially above the generally recognized intervention threshold of 20% over 10 years. The question of how to further reduce residual coronary risk without compromising patient safety in patients on optimal statin therapy remains an important clinical challenge.