The influence of aging on the prognostic value of the revised cardiac risk index for postoperative cardiac complications in vascular surgery patients.

Abstract

The Lee-risk index [Lee-index] was developed to predict major adverse cardiac events [MACE]. However, age is not included as a risk factor. The aim was to assess the value of the Lee-index in vascular surgery patients among different age categories. Of 2642 patients cardiovascular risk factors were noted to calculate the Lee-index. Patients were divided into four age categories; < or = 55 (n=396), 56-65 (n=650), 66-75 (n=1058) and > 75 years (n=538). Outcome measures were postoperative MACE (cardiac death, MI, coronary revascularization and heart failure). The performance of the Lee-index was determined using C-statistics within the four age groups. The incidence of MACE was 10.9%, for Lee-index 1, 2 and > or = 3; 6%, 13% and 20%, respectively. However, the prognostic value differed among age groups. The predictive value for MACE was highest among patients under 55 year (0.76 vs 0.62 of patients aged > 75). The prediction of MACE improved in elderly (aged > 75) after adjusting the Lee-index with age, revised risk of operation (low, low-intermediate, high-intermediate and high-risk procedures) and hypertension (0.62 to 0.69). The prognostic value of the Lee-index is reduced in elderly vascular surgery patients, adjustment with age, risk of surgical procedure, and hypertension improves the Lee-index significantly.