Lipoprotein lipase activity is associated with severity of angina pectoris

Background-Raised triglyceride-rich lipoproteins significantly increase the risk for cardiovascular disease. Variation in the activity of the enzyme l ipoprotein lipase (LPL), which is crucial in the removal of these lipoprote ins, may therefore modulate this risk. Methods and Results-Postheparin levels of LPL activity and mass were measur ed in a large cohort of male coronary artery disease patients participating in the Regression Growth Evaluation Statin Study (REGRESS), a lipid-loweri ng regression trial. In addition, the relationships between LPL activity an d mass and severity of angina pectoris according to the NYHA classification and silent ischemia on 24-hour ambulatory ECG monitoring were assessed. Pa tients in different LPL activity quartiles and mass had different severitie s of angina; a total of 47% of patients in the lowest LPL quartile reported class III or IV angina. In contrast, only 29% in the highest activity quar tile (P=0.002) had severe angina. These parameters were supported by ambula tory ECG results, for which the total ischemic burden in the lowest LPL act ivity quartile was 36.5+/-104.1 mmxmin compared with 14.8+/-38.8 mmxmin in the highest quartile of LPL activity (P=0.001), LPL activity levels were st rongly correlated with LPL mass (r=0.70, P<0.0001). A significant associati on between the LPL protein mass and NYHA class (P=0.012) was also demonstra ted. Conclusions-We have demonstrated a significant relationship between LPL mas s and activity and severity of ischemia as defined by angina class and ambu latory EGG. These results suggest that LPL influences risk for coronary art ery disease by both catalytic and noncatalytic mechanisms.