Comparison of non-fasting LDL-C levels calculated by Friedewald formula with those directly measured in Chinese patients with coronary heart disease after a daily breakfast.
Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, PR China; Research Institute of Blood Lipid and Atherosclerosis, Central South University, Changsha, Hunan 410011, PR China. Electronic address: [Email]
BACKGROUND : LDL-C level can be measured by direct methods (LDL-CM) or calculated by Friedewald formula (LDL-CC). The aim of this study was to investigate the difference between LDL-CM and LDL-CC after a daily breakfast in Chinese patients with coronary heart disease (CHD). METHODS : Three hundred and three inpatients, including 203 CHD patients (CHD group) and 100 non-CHD controls (CON group), were enrolled in this study. Serum levels of blood lipid parameters, including LDL-CC and LDL-CM, at 0, 2 and 4 h (h) were monitored after a daily breakfast in all subjects. RESULTS : LDL-CM was significantly higher than LDL-CC in fasting state in each group and at 4 h postprandially in CHD group (P < .05). Postprandial LDL-CM and LDL-CC significantly decreased in each group (P < .05). Postprandial decline in LDL-CM was significantly greater than that of LDL-CC (P < .05). For CHD patients taking statins for ≥1 month before admission, non-fasting percent attainment of LDL-CM or LDL-CC was significantly higher than its fasting value, especially at 4 h (P < .05). The percent deviation of LDL-CM from 1.8 mmol/L at 4 h was significantly different from its fasting value. However, there was no significant difference in percent deviation of LDL-CC from 1.8 mmol/L between fasting and non-fasting states. CONCLUSIONS : It indicated that the clinical monitoring of non-fasting LDL-C level in CHD patients could be relatively complex, and the judgement may depend not only on the method to acquire LDL-C level, but also on the evaluation method.