EFFECTIVE LIPID MODIFICATION BY PARTIAL ILEAL BYPASS REDUCED LONG-TERM CORONARY HEART-DISEASE MORTALITY AND MORBIDITY - 5-YEAR POSTTRIAL FOLLOW-UP REPORT FROM THE POSCH

Background: In 1990, when the Program on the Surgical Control of the H yperlipidemias (POSCH) reported its in-trial results strongly supporti ng the conclusion that effective lipid modification reduces progressio n of atherosclerosis, the differences for the end points of overall mo rtality and mortality from atherosclerotic coronary heart disease (ACH D) did not reach statistical significance. Methods: The Program on the Surgical Control of the Hyperlipidemias recruited men and women with a single documented myocardial infarction between the ages of 30 and 6 4 years who had a plasma cholesterol level higher than 5.69 mmol/L (22 0 mg/dL) or higher than 5.17 mmol/L (200 mg/dL) if the low-density lip oprotein cholesterol level was in excess of 3.62 mmol/L (140 mg/dL). B etween 1975 and 1983, 838 patients were randomized: 417 to the diet co ntrol group and 421 to the diet plus partial ileal bypass intervention group. Mean patient follow-up for this 5-year posttrial report was 14 .7 years (range, 12.2-20 years). Results: At 5 years after the trial, statistical significance was obtained for differences in overall morta lity (P = .049) and mortality from ACHD (P = .03). Other POSCH end poi nts included overall mortality (left ventricular ejection fraction gre ater than or equal to 50%) (P = .01), mortality from ACHD (left ventri cular ejection fraction greater than or equal to 50%) (P = .05), morta lity from ACHD and confirmed nonfatal myocardial infarction (P<.001), confirmed nonfatal myocardial infarction (P<.001), mortality from ACHD , confirmed and suspected myocardial infarction and unstable angina (P <.001), incidence of coronary artery bypass grafting or percutaneous t ransluminal coronary angioplasty (P<.001), and onset of clinical perip heral vascular disease (P = .02). There were no statistically signific ant differences between groups for cerebrovascular events, mortality f rom non-ACHD, and cancer. All POSCH patients have been available for f ollow-up. Conclusion: At 5 years after the trial, all POSCH mortality and atherosclerosis end points, including overall mortality and mortal ity from ACHD, demonstrated statistically significant differences betw een the study groups.