Quality of life after myocardial revascularization. Effect of increasing age

Abstract

The effect of increasing age on quality of life, survival, and risk of reoperation was studied in 2479 patients followed up prospectively 2 to 20 years after myocardial revascularization. Quality of life was determined from annual questionnaires, which we used to calculate a health status index from the patient's symptomatic status and subjective response to the operation, which was graded between zero and 1.00 (asymptomatic). Four age groups were studied: age 49 years or less (AG40), 50 to 59 years (AG50), 60 to 69 years (AG60), and 70 years or older (AG70). Associated problems (left ventricular aneurysm, valve disease, acute myocardial infarction) necessitating treatment were present in 17% (61/361) of AG40 patients, 19% (165 of 859) of AG50 patients, 23% (213/927) of AG60 patients, and 31% (102/332) of AG70 patients. The hospital mortality rate was higher in older patients undergoing combined procedures but not in patients undergoing coronary bypass grafts only. Probability of survival and health status indexes were calculated excluding patients with valve disease and cardiogenic shock. Probability of survival was significantly better (p less than 0.001 by the Wilcoxon test) in patients less than age 60 than in those 60 years or older, but in patients with an ejection fraction greater than or equal to 0.40, probability of survival at 12 years was 0.64 (age less than 60) versus 0.62 (age greater than or equal to 60). The actuarial risk of reoperation, calculated as the difference between probability of survival and probability of survival without reoperation, progressively increased in younger patients but not in patients aged 60 years or older. At 15 years, the reoperation rates were 26% (AG40), 14% (AG50), 5% (AG60), and 7% (AG70). Mean health status index for years 1 to 5 was 0.85 in AG40 patients, 0.84 in AG50 patients, 0.89 in AG60 patients, and 0.90 in AG70 patients; for years 6 to 10, 0.81, 0.80, 0.86, and 0.89; and for years 11 to 15, 0.77, 0.78, 0.84, and 0.84, respectively. Thus quality of life after myocardial revascularization is better, improvement lasts longer, and reoperation rate is less in patients aged 60 years or older.