Impact of fasting on lipid profile assessment of Brazilian adults

Dyslipidemia is a common cardiovascular risk factor, with ongoing debate over whether lipid profile assessment, with or without fasting, affects the accuracy of cardiovascular risk evaluation. The objective of this study is to evaluate the effect of fasting status on lipid profile values and the prevalence of dyslipidemia.

A total of 269 adults (20-69 years) from Vitória-ES (Brazil) were included. Two blood samples were collected on the same day: one in the morning after a 10-12-hour fast and the other in the afternoon, post-lunch (1-5 pm). Dyslipidemias were classified according to the Brazilian Guidelines.

The percentage of participants classified with low HDL-c (male: 54.2 vs. 38.2%, p < 0.001; female: 29.7 vs. 15.2%, p < 0.001) and hypertriglyceridemia (male: 59.5 vs. 26.7%, p < 0.001; female: 50.0 vs. 22.5%, p < 0.001) was higher in the non-fasting state. Furthermore, HDL-c levels were higher in after fasting. Triglyceride levels were higher in the non-fasting state, while LDL-c concentrations were slightly reduced in the non-fasting state. Without fasting, 85 individuals previously classified as having normal TG were reclassified as having hypertriglyceridemia, and 41 individuals previously classified as having normal HDL-c were reclassified as having low HDL-c.

The feeding state is key to detecting and managing dyslipidemias, especially hypertriglyceridemia and low HDL-c. Removing the fasting requirement could improve cardiovascular risk identification, increase patient adherence to testing and treatment. However, the significant differences in the lipid profile concentrations must be considered in the patient's management in the clinical practice.