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s / Atherosclerosis 275 (2018) e104ee255 e157 P2.2.181. PLASMA CLEARANCE OF CHYLOMICRON REMNANTS IS DELAYED IN AGED SUBJECTS: A STUDY WITH ARTIFICIAL EMULSIONS T.M. Tavoni , C.G. Vinagre , F.R. Freitas , C.H. Mesquita , J.C. Vinagre , A.C. Mariani , R. Kalil-Filho , R.C. Maranhao . Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of S~ ao Paulo, S~ ao Paulo, Brazil; University of Santo Amaro, S~ ao Paulo, Brazil; Heart Institute (InCor) of Medical School Hospital, University of S~ ao Paulo, S~ ao Paulo, Brazil; 4 Institute of Nuclear Research, S~ ao Paulo, Brazil Aim: Dietary fats absorbed in the intestine are transported in the circulation as chylomicrons and remnants that have atherogenic potential. Although postprandial lipidemia is increased in older subjects, the specific chylomicron metabolism has not been explored in older subjects nor compared to young subjects, which is the focus of this study. Methods: After a 12 h fast, artificially-made emulsions similar to lymph chylomicrons and doubly labeled with radioactive cholesteryl esters and triglycerides were intravenously injected in 23 older (66±4 years) and 20 young (24±3 years) subjects. Sequential blood samples were collected to determine fractional clearance rates (FCR, in min-1) by compartmental analysis. Results: Older subjects had higher LDL-cholesterol (p<0.001) and triglycerides (p<0.0001) than young subjects; HDL-cholesterol presented no difference. The emulsion cholesteryl-ester FCR was lower in older subjects compared to the young (p1⁄40.0001). The emulsion triglyceride FCR did not differ in the two groups. Tested in vitro, however, the lipolysis of the emulsion triglycerides was less intense in the older than in the young subjects. Conclusions: As delayed removal of remnants, indicated by the pronouncedly smaller cholesteryl ester FCR, is related to the presence of cardiovascular diseases, this can be a risk factor which could accelerate atherogenic complications occurring in aged subjects. P2.2.182. CHYLOMICRON METABOLISM IS IMPAIRED IN PATIENTS WITH OBSTRUCTIVE SLEEP APNEA: EFFECTS OF TREATMENT WITH CONTINUOUS POSITIVE AIRWAY PRESSURE L.F. Drager , T.M. Tavoni , V.M. Silva , R.D. Santos , R.P. Pedrosa , L.A. Bortolotto , C.G. Vinagre , V.Y. Polotsky , G. Lorenzi-filho , R.C. Maranhao . Heart Institute (InCor) of Medical School Hospital, University of S~ ao Paulo, S~ ao Paulo, Brazil; 2 Faculty of Pharmaceutical Sciences, University of S~ ao Paulo, S~ ao Paulo, Brazil; 3 Sleep and Heart Laboratory, University of Pernambuco, Recife, Brazil; University of Santo Amaro, S~ ao Paulo, Brazil; 5 Johns Hopkins University School of Medicine,