As the population ages, an increasing number of elderly patients become candidates for major surgery. According to the National Center for Health Statistics, the rate of hospital discharges for hip replacement in elderly people rose from 2.5 per 10 000 in 1970 to 72.5 per 10 000 in 2004 (http://www.cdc.gov/nchs/agingact.htm). Based on current rates of surgery and census projections, the number of elderly patients undergoing oncologic procedures is expected to increase by up to 51% by the year 2020.
Surgical risks in general are declining over time, and many assume that surgery for elderly patients is getting safer. Case series suggest that surgery can be performed with low morbidity and mortality in elderly people. For lung, esophageal, and pancreatic resection, single-center studies report operative mortality rates between 3% and 4% in very elderly patients. Case series are advocating bariatric surgery in obese patients older than 65 years, touting low morbidity and mortality rates.
Results from clinical series, however, may lead to unrealistic expectations about the safety of surgery in the elderly population, as many published studies have selection bias. Reports of operative mortality tend to represent experiences of high-volume, tertiary academic centers. It is well documented that for high-risk cancer surgery, high-volume surgeons and hospitals have superior outcomes. In addition, results from case series are more likely to be submitted and published if the observed mortality is low, resulting in a publication bias toward lower operative mortality. As a result, existing data generally yield unrealistic risk estimates.
This chapter examines operative risk in very elderly patients using “real-world” results from large databases. In addition, evidence will be reviewed about predictors of surgical outcomes in elderly patients—fatal surgical outcomes as well as functional status and independence after major surgery.
In general, increasing age is associated with increased rates of morbidity, functional dependence, and mortality after surgery. Countless studies for several decades have documented that age predicts adverse outcomes after surgery. In a comprehensive analysis of more than 50 0000 patients undergoing noncardiac surgery in the Veterans Affairs National Surgical Quality Improvement Project (NSQIP) database, Hamel et al. found that age was an independent predictor of operative mortality, after adjusting for comorbidities. For all operations in aggregate, 30-day mortality was 2.8% for patients younger than 80 years compared with 8.2% in older patients. For colectomy, mortality was 6.4% in younger patients versus 11.9% in older patients. Similarly, younger patients undergoing elective hip replacement had much lower operative risk (1.3%) when compared to older patients (6.8%). In a single-center study, patients aged 80 years and older had a fourfold increase in risk of both operative mortality and discharge to nursing home after cardiac surgery. This finding persisted after adjustment for patient characteristics. Age is also a known independent predictor of deterioration in cognitive function after coronary artery bypass graft (CABG) surgery.
To assess the impact of age on mortality for a ...