Fasting time and lipid parameters: association with hepatic steatosis--data from a random population sample.
BACKGROUND
Current guidelines recommend measuring plasma lipids in fasting patients. Recent studies, however, suggest that variation in plasma lipid concentrations secondary to fasting time may be minimal. Objective of the present study was to investigate the impact of fasting time on plasma lipid concentrations (total cholesterol, HDL and LDL cholesterol, triglycerides). A second objective was to determine the effect of non-alcoholic fatty liver disease exerted on the above-mentioned lipid levels.


METHODS
Subjects participating in a population-based cross-sectional study (2,445 subjects; 51.7% females) were questioned at time of phlebotomy regarding duration of pre-phlebotomy fasting. Total cholesterol, LDL and HDL cholesterol, and triglycerides were determined and correlated with length of fasting. An upper abdominal ultrasonographic examination was performed and body-mass index (BMI) and waist-to-hip ratio (WHR) were calculated. Subjects were divided into three groups based on their reported fasting periods of 1-4 h, 4-8 h and > 8 h. After application of the exclusion criteria, a total of 1,195 subjects (52.4% females) were included in the study collective. The Kruskal-Wallis test was used for continuous variables and the chi-square test for categorical variables. The effects of age, BMI, WHR, alcohol consumption, fasting time and hepatic steatosis on the respective lipid variables were analyzed using multivariate logistic regression.


RESULTS
At multivariate analysis, fasting time was associated with elevated triglycerides (p = 0.0047 for 1-4 h and p = 0.0147 for 4-8 h among females; p < 0.0001 for 1-4 h and p = 0.0002 for 4-8 h among males) and reduced LDL cholesterol levels (p = 0.0003 for 1-4 h and p = 0.0327 for 4-8 h among males). Among males, hepatic steatosis represents an independent factor affecting elevated total cholesterol (p = 0.0278) and triglyceride concentrations (p = 0.0002).


CONCLUSIONS
Total and HDL cholesterol concentrations are subject to slight variations in relation to the duration of the pre-phlebotomy fasting period. LDL cholesterol and triglycerides exhibit highly significant variability; the greatest impact is seen with the triglycerides. Fasting time represents an independent factor for reduced LDL cholesterol and elevated triglyceride concentrations. There is a close association between elevated lipids and hepatic steatosis.
Martin
M
Gruchot
Tilmann
T
Graeter
Suemeyra
S
Oeztuerk
Mark Martin
MM
Haenle
Wolfgang
W
Koenig
Armin
A
Imhof
Bernhard Otto
BO
Boehm
Richard Andrew
RA
Mason
Department of Internal Medicine I, University Hospital Ulm, Albert-Einstein-Allee 23, 89081 Ulm, Germany. wolfgang.kratzer@uniklinik-ulm.de.
Wolfgang
W
Kratzer
Atilla Serif
AS
Akinli
D000328:Adult; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D003430:Cross-Sectional Studies; D005215:Fasting / Q000097:blood*; D005234:Fatty Liver / Q000097:blood* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015995:Prevalence; D013997:Time Factors; D014280:Triglycerides / Q000097:blood*
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D014280:Triglycerides