GASTROENTEROLOGY 79:96-94,198O Biliary Lipid Composition in Normo- and Hyperlipoproteinemia JON AHLBERG, BO ANGELIN, KURT EINARSSON, KJELL HELLSTROM, and BARBRO LEIJD Departments of Medicine and Surgery, Karolinska Institutet at Serafimerlasarettet, Stockholm, Sweden The lipid composition of fasting gallbladder bile ob- tained under standardized conditions w as deter- mined in healthy controls and in patients with hy- perlipoproteinemia without gallstones. Altogether 23 normohpidemic controls (10 males and 13 females) and 50 hyperhpidemic patients (31 type Ila, 7 type Ilb, and 12 type IV) were studied; all were less than 15% overweight. The cholesterol saturation averaged 96 f 5% (mean + SEM) in the controls, and 10 of them had bile supersaturated with cholesterol. There was no difference between males and females. An increased saturation with age was seen in fe- males. A normal biliary cholesterol saturation (102 -+ 3%) was found in patients with hyperlipopro- teinemia type Jla; this was true also for the subgroup with established familial hypercholesterolemia. Ah patients with hyperhpoproteinemia type IIb and 10 of those with type IV had saturated bile (135 + 8% and 121 f 6%, respectively). The results suggest an association between certain forms of hyper- Jipoproteinemia and the development of super- saturated bile. Since fasting gallbladder bile super- saturated with cholesterol is considered to precede gallstone formation, the present results may explain Received September 24, 1979. Accepted January 27, 1986. Address requests for reprints to: Dr. Kurt Einarsson, Depart- ment of Medicine, Huddinge University Hospital, S-141 86 Hud- dinge, Sweden. This study was supported by grants from the Swedish Medical Research Council (project No. 19X-04793), and from the Loo and Hans Osterman Foundation. Dr. Angelin is the recipient of a re- search fellowship from the Ernst Klenk Foundation. See NAPS Document No. 03639 for 9 pages of supplementary material. Order from: NAPS c/o Microfiche Publications, P.O. Box 3513, Grand Central Station, New York, NY 16617. Remit in advance in U.S. funds only $3.66 for photocopies or $3.66 for mi- crofiche. Outside the U.S. and Canada, add postage of $3.66 for photocopy and $1.66 for microfiche. The authors are grateful to Mrs. Ruth Detlofsson. Mrs. Kerstin Hedstrom, Mrs. Eija Varhenmaa, and Mrs. Margret Wahlstrijm for skillful technical assistance. 0 1986 by the American Gastroenterological Association 6616-5085/60/076690-05$02.25 previous findings of an increased prevalence of gallstone disease in patients with hyper- triglyceridemia. According to current concepts, the formation of cho- lesterol gallstones is preceded by metabolic defects resulting in the development of supersaturated bile.‘,’ An increased cholesterol saturation of bile has thus been demonstrated in obesity and during treatment with clofibrate and contraceptive steroids, conditions associated with an increased occurrence of gallstone disease.* We have recently reported that hyperlipoproteinemia type IV is associated with an increased prevalence of gallbladder disease (GBD, i.e., cholelithiasis, cholecystitis, cholecystectomy), whereas in HLP type IIa the occurrence of GBD ap- pears to remain within normal limits.“,’ The present investigation was undertaken to obtain further in- formation on the possible association between HLP and cholesterol gallstone disease. Lipid composition of gallbladder bile obtained under standardized con- ditions was determined in gallstone-free, nonobese subjects including a normolipidemic group and pa- tients with three types of HLP. Methods Subjects The study comprised 23 nonobese (relative body wt < 115% ) normolipidemic subjects, and 50 nonobese hy- perlipidemic patients. Only subjects with a normal chole- cystogram were included. The hyperlipidemic patients were those consecutively admitted because of primary HLP at the time of the investigation. They were separated into three groups on the basis of their lipoprotein pattern (see below). None showed evidence of hepatic, intestinal, or renal disease, hyper- or hypothyroidism, or addiction to drugs or alcohol. Excluded were those with diabetes, HLP type III, or type V. About 25% of the patients had ischemic heart disease (history of myocardial infarction and/or