The combined effect of transferrin saturation and low density lipoprotein on mortality.
OBJECTIVE
Evidence suggests that cardiovascular disease (CVD) is accelerated by the oxidation of low-density lipoprotein (LDL) in the presence of iron. This study examined whether adults with elevated iron, as measured by transferrin saturation (TS), and elevated LDL are at an increased risk for mortality.


METHODS
This is a cohort study of the adult US population using the National Health and Nutrition Examination Survey 1976-1980 (NHANES II) merged with the NHANES II Mortality Study in 1992. Multivariate Cox regression was performed to determine hazard ratios (HR) for CVD and all-cause mortality for high (>55%) or low (<55%) levels of TS and high (>160 mg/dl) or low (<160 mg/dl) levels of LDL.


RESULTS
An elevated LDL alone did not significantly increase CVD mortality or all-cause mortality in the adjusted model. Individuals with elevated LDL and elevated TS had a statistically significant increase in both CVD mortality and all-cause mortality (HR=5.74 and 3.53, respectively) compared to the low LDL and low TS group.


CONCLUSIONS
The results of this study indicate an increased risk associated with the combination of elevated LDL and elevated TS, which suggests that iron-mediated oxidation of LDL may be a significant factor in the progression of CVD.
Wells
Brian J
BJ
Department of Family Medicine, Medical University of South Carolina, Charleston 29425, USA. wellsbj@musc.edu
Mainous
Arch G
AG
King
Dana E
DE
Gill
James M
JM
Carek
Peter J
PJ
Geesey
Mark E
ME
D000328:Adult; D000368:Aged; D015415:Biomarkers; D002318:Cardiovascular Diseases / Q000401:mortality*; D008078:Cholesterol, LDL / Q000097:blood*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D016016:Proportional Hazards Models; D012306:Risk; D014168:Transferrin / Q000378:metabolism*; D014481:United States / Q000453:epidemiology
D015415:Biomarkers; D008078:Cholesterol, LDL; D014168:Transferrin