Lipid management in high risk coronary patients: how effective are we at secondary intervention?

To assess the proportion of patients who achieve and maintain target lipid levels during optimum long term follow up after coronary bypass surgery.

From a prospectively compiled database, we identified 440 patients followed for up to 13 years after CABG as part of a radial artery randomised controlled trial. All available lipid assays conducted during the follow-up period were collected from pathology databases. These were used to calculate the annualised mean lipid exposure for each patient. Based upon National Heart Foundation guidelines, we determined the proportion of patients whose mean lipid exposure attained target levels (total cholesterol <4.0 mmol/L, LDL-C <2.0 mmol/L, HDL-C >1.0 mmol/L and triglycerides <1.5 mmol/L). This was compared with the proportion who had achieved these targets pre-operatively and on their most recent cholesterol measurement.

6077 lipid studies (total cholesterol, LDL, HDL and triglycerides) in total were obtained. In those who had baseline data available, target levels for total cholesterol, HDL-C, LDL-C and triglycerides were attained pre-operatively by 16%, 64%, 14% and 39% of patients respectively. Annualised mean lipid exposures during up to 13 years of follow up for all patients revealed somewhat improved but still suboptimal target attainment figures of 24%, 83%, 20% and 53%. The most recent review shows the greatest improvement at 47%, 68%, 43% and 62% respectively. Of 141 diabetic patients, target attainment was significantly higher for total cholesterol (31%; p=0.038) and LDL-C (28%; p=0.006) but lower for HDL-C (75%; p=0.002) and triglycerides (40%; p<0.001).

Despite some improvements seen over careful follow up, only HDL-C targets appear attainable for the majority of CABG patients. Over half still do not achieve non-HDL national lipid targets.