Overall mortality, incremental life expectancy, and cause of death at 25 years in the program on the surgical control of the hyperlipidemias

Abstract

Objective: To present the longest follow-up report of any lipid-atherosclerosis intervention trial.

Summary of background data: The Program on the Surgical Control of the Hyperlipidemias (POSCH), a secondary, clinical/arteriographic, randomized controlled trial, was the first lipid-atherosclerosis trial to demonstrate unequivocally that low density lipoprotein cholesterol reduction reduced the incidence of coronary heart disease death and myocardial infarction.

Methods: We report POSCH 25 years follow-up for overall mortality, specific cause of death, and certain subgroup analyses, as well as a prediction for increase in life expectancy derived from the POSCH database, supplemented by the 2006 National Death Index, 1989-2006.

Results: There were 838 patients randomized in POSCH (421 surgery, 417 control). At 25 years follow-up, the difference in the restricted mean survival and the logrank (Mantel-Haenszel) statistic was statistically significant, with survival probabilities of 0.57 (surgery) and 0.51 (controls). Cause of death data indicated a significant increase in cardiovascular deaths in the control group; cancer deaths were also greater in the control group but this was not significant. The most compelling subgroup analysis was a significant increase in survival, starting at 5 years after randomization, in the surgery group for patients with an ejection fraction > or = 50%, with relative probabilities of 0.61 (surgery) and 0.51 (control). The estimated incremental increase in life expectancy over more than 25 years of follow-up was 1.0 year overall and 1.7 years in the cohort with an ejection fraction > or = 50%.

Conclusions: A 25-year mortality follow-up in POSCH shows statistically significant gains in overall survival, cardiovascular disease-free survival, and life expectancy in the surgery group compared with the control group.