Results of surgery: long-term effects on hyperlipidemia

Abstract

To define frequency of lipid abnormalities and to monitor improvement or correction of those abnormalities postoperatively, 66 patients with chronic morbid obesity had total cholesterol, high-density-lipoprotein (HDL) cholesterol, and triglyceride determinations preoperatively and at staged intervals up to 5-7 y after Roux-Y gastric bypass. Preoperative abnormal HDL-cholesterol and triglyceride concentrations were frequent. Major improvements occurred in these lipid concentrations by 6 mo postoperatively, and some further improvements occurred with additional weight loss at 1 y. At 5-7 y, among 33 patients, raised concentrations of HDL cholesterol were upheld in women (P less than 0.01); reductions in triglycerides were maintained in men (P less than 0.025); and reduced total cholesterol:HDL-cholesterol, which was achieved by 6 mo, was sustained in both men and women (P less than 0.01). In comparing lipid profiles of gastric surgery through 5 y with recent data from the surgical arm of the Program on Surgical Control of the Hyperlipidemias (POSCH), postulates are made of anticipated reduction in morbid, and even fatal, cardiac events in the operated morbidly obese population.

Increased Expression and Activity of Hepatic Lipase in the Liver of Morbidly Obese Adult Patients in Relation to Lipid Content

“…Other authors [46] have also described the high HL activity, although in postheparin plasma, this is a reflection of an altered lipoprotein profile in very obese women. In agreement with previous reports [47][48][49], we observed that following bariatric surgery, there was a drastic reduction in TAG levels in both the liver and plasma, as well as in levels of TC, although, here, this reduction was more marked than that found by other authors [50]. This reduction in the TAG content of hepatocytes is accompanied by a reduced amount of other lipids (TC, PL, etc.…”

Lipoprotein Lipase Expression in Livers of Morbidly Obese Patients Could be Responsible for Liver Steatosis

“…In agreement with previous reports [36][37][38], we observed that, following bariatric surgery, there was a drastic reduction in TAG levels in both liver and plasma, as well as in levels of TC, although in the present study, this reduction was more marked than that found by some authors [39]. This reduction in the TAG content in hepatocytes is accompanied by a reduced amount of other lipids (TC, PL, etc.…”

Bariatric Surgery and Cardiovascular Risk Factors

“…Total cholesterol was modestly reduced 55,76,78,82,83 and low-density lipoprotein (LDL) cholesterol typically was not affected by these procedures. 83,84 As would be expected, the ratio of total cholesterol to HDL was consistently improved (driven by the improvements in HDL) after weight loss surgery 78,80,81,83,85 (Table 3). Weight loss and resultant improvements in hepatic insulin sensitivity likely explain these findings; however, the exact mechanisms for the benefits seen in dyslipidemia after weight loss surgery are not clear.…”