Lower concentrations of carotenoids in the critically ill patient are related to a systemic inflammatory response and increased lipid peroxidation.
BACKGROUND
Critically-ill patients have low circulating concentrations of vitamin antioxidants. The functional significance of such reductions is not clear.


OBJECTIVE
To determine whether the presence of a systemic inflammatory response was associated with reduced circulating alpha-tocopherol and carotenoid concentrations and an increase in lipid peroxidation as evidenced by malondialdehyde.


METHODS
Healthy controls (n=24) and critically-ill patients (n=43) had circulating concentrations of C-reactive protein, cholesterol, triglycerides, malondialdehyde, alpha-tocopherol, lutein, lycopene, alpha- and beta-carotene measured during ITU stay.


RESULTS
In the critically-ill group circulating concentrations of C-reactive protein and malondialdehyde were significantly higher (P<0.05) and cholesterol, triglyceride, alpha-tocopherol, lutein, lycopene, alpha- and beta-carotene were all significantly lower (P<0.01) compared with the control group. In the critically-ill group alpha- and beta-carotene were below detection limits for many patients. After adjusting for cholesterol, lycopene concentrations remained significantly lower (P<0.001) compared with the control group. In the critically-ill patients circulating concentrations of C-reactive protein and malondialdehyde were significantly correlated (r=0.502,P<0.01).


CONCLUSIONS
The systemic inflammatory response is associated with increased lipid peroxidation and low carotenoid concentrations indicating that inflammation driven breakdown of carotenoids is an important factor in lowering circulating carotenoid concentrations in the critically-ill patient.
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000975:Antioxidants / Q000378:metabolism*; D002097:C-Reactive Protein / Q000378:metabolism*; D002338:Carotenoids / Q000097:blood*; D016022:Case-Control Studies; D002784:Cholesterol / Q000097:blood; D016638:Critical Illness; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D014280:Triglycerides / Q000097:blood
D000975:Antioxidants; D014280:Triglycerides; D002338:Carotenoids; D008315:Malondialdehyde; D002097:C-Reactive Protein; D002784:Cholesterol