Hyperlipidemia surgical

Conjugated bile salts are normally absorbed in the terminal ileum. Disease of the terminal ileum (eg, Crohn s disease) or surgical resection leads to malabsorption of bile salts, which may cause colonic secretory diarrhea. The bile salt binding resins cholestyramine or colestipol may decrease diarrhea caused by excess fecal bile acids (see Chapter 35 Agents Used in Hyperlipidemia). The usual dose is 4-5 g one to three times daily before meals. Side effects include bloating, flatulence, constipation, and fecal impaction. In patients with diminished circulating bile acid pools, further removal of bile acids may lead to an exacerbation of fat malabsorption. These agents bind a number... 

Two studies evaluated the effects of lipid-lowering therapy on clinical endpoints in the leg. The Program on the Surgical Control of the Hyperlipidemias was a randomized trial of partial ileal-bypass surgery for the treatment of hyperlipidemia in 838 patients (9). After five years, the relative risk (RR) of an abnormal ankle-brachial index value (ABI) was 0.6 (95% Cl, 0.4 to 0.9, absolute risk reduction, 15% points, p < 0.01), and the RR of claudication or limb-threatening ischemia was 0.7 (95% Cl, 0.2 to 0.9, absolute risk reduction, 7% points, p < 0.01), as compared with the control group. 

Buchwald H, Bourdages HR, Campos CT, et al. Impact of cholesterol reduction on peripheral arterial disease in the Program on the Surgical Control of the Hyperlipidemias (POSCH). Surgery 1996 120 672-679. 

Partial ileal bypass has been used in severe heterozygous and homozygous familial hypercholesterolemia however, it is ineffective in the latter case. Ileal bypass removes the site of bile acid reabsorption, depleting the bile acid pool and increasing the catabolism of cholesterol. A randomized trial of diet versus surgery, called Program On the Surgical Control of the Hyperlipidemias (POSCH), reported... 

POSCH Program on the Surgical Control of the Hyperlipidemias PROSPER Prospective Study of Pravastatin in the Elderly at Risk PROVE-IT Pravastatin or Atorvastatin Evaluation and Infection Therapy... 

These studies suggest the importance of TG-rich lipoprotein reduction and HDL raising for the retardation of atherosclerosis in mild to moderate lesions, and a role for fibric acid derivatives in secondary prevention. Analysis of data from Cholesterol Lowering Atherosclerosis Study (CLAS), the Program on the Surgical Control of Hyperlipidemias (POSCH), and MARS studies also provide evidence for the importance of TG rich lipoprotein in progression of CAD. 

Buchwald H, Varco RL, Marts JP, Long JM, Pitch LL, Campbell GS, et al. Effect of partial ileal bypass surgery on mortality and morbidity from coronary heart disease in patients with hypercholesterolemia. Report of the Program on the Surgical Control of Hyperlipidemias (POSCH). N Eng J Med 1990 323 946-955. 

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