RESUMEN
@#【Objective】The aim of this study was to investigate the associations between serum complement C3，C4 and low density lipoprotein cholesterol（LDL- C）levels and early- onset coronary heart disease.【Methods】We enrolled 255 cases of coronary angiography confirmed coronary artery disease from January 2018 to September 2018. All the patients were divided into early- onset coronary heart disease group（108 cases）and late- onset coronary heart disease group（147 cases）. Besides ，100 healthy subjects were enrolled and used as controls. Serum levels of C3 ，C4 and LDL-C were analyzed by automatic biochemical analyzer.【Results】Levels of serum C3，C4 and LDL-C in early-onset coronary heart disease group，late-onset coronary heart disease group and healthy control group were significantly different（P < 0.05）. In early-onset coronary heart disease group，C3 and C4 were positively correlated with LDL-C（P < 0.05）. However ，there was no significant correlation （P > 0.05） between C3 ，C4 and LDL- C in late- onset coronary heart disease group and healthy control group.【Conclusions】The levels of C3 and C4 were positively correlated with LDL-C only in the early-onset coronary heart disease patients.