Plasma cholesterol fractions after jejunoileal bypass with 3:1 or 1:3 jejunoileal ratio

Jejunoileal bypass results in a 40% reduction in total plasma cholesterol both with a 3:1 and with a 1:3 jejunoileal ratio of the segments left in continuity, in spite of a lower rate of cholesterol degradation to bile salts with a 1:3 jejunoileal ratio. We measured total cholesterol, total triglycerides, and high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol in plasma from 34 patients who either were waiting for or had had bypass surgery with 3:1 or 1:3 jejunoileal ratio 3, 9, or 15 months earlier. Total cholesterol and triglycerides were significantly reduced after bypass surgery but showed no significant difference between 3:1 and 1:3 bypass and no significant changes with time after surgery. The HDL cholesterol showed no significant differences between the groups except for a moderately decreased level in the 1:3 bypass group 3 months after surgery. LDL cholesterol was pronouncedly reduced in the bypass groups compared with the unoperated group and was not significantly related to the jejunoileal ratio of the bypass or to the time since surgery.