Syncope in the elderly.

This report describes the evaluation of syncope in 210 elderly patients as compared with 190 younger patients. The elderly group had a mean age of 71 years (range 60 to 90) and the younger group had a mean age of 39 years (range 15 to 59). A cardiovascular cause was found in 33.8 percent of the elderly and in 16.8 percent of the young (p = 0.0001), a noncardiovascular cause in 26.7 percent of the elderly and 37.9 percent of the young (p = 0.02), and unknown cause in 38.5 percent of the elderly and 45.3 percent of the young (NS). Prolonged electrocardiographic monitoring established the diagnosis in 17 percent of the elderly but in only 8 percent of the young (p = 0.008). Syncope resulted in trauma in 39 percent of the elderly and in 32 percent of the young, but the elderly more often had major trauma. The two-year overall mortality was 26.9 +/- 3.4 percent in the elderly and 8.3 +/- 2.1 percent in the young (p less than 0.0001). The overall mortality and incidence of sudden death in the elderly with a cardiovascular diagnosis were similar to those in the young; however, in the elderly with a noncardiovascular diagnosis and syncope of unknown cause, the mortality and incidence of sudden death were higher. Multivariate analyses using mortality and sudden death as endpoints revealed that a cardiovascular cause of syncope was a very strong risk factor. In patients with a noncardiovascular cause or unknown cause of syncope, a history of congestive heart failure, older age, and male sex are important prognostic factors.