Baseline comorbidities and treatment strategy in elderly patients are associated with outcome of cardiogenic shock in a community-based population

Abstract

Background Cardiogenic shock (CGS) historically results in high inhospital mortality, particularly in elderly patients. Factors that contribute to increased mortality and treatment strategies that improve short- and long-term outcomes in patients with CGS remain to be established. Methods The study consisted of 1263 consecutive patients with acute myocardial infarction admitted from Olmsted County, Minn, during the period 1988 to 2000; of these, 73 (6%) developed cardiogenic shock. Short- and long-term mortality was compared between the elderly and younger populations in both shock and nonshock groups. Results In patients with acute myocardial infarction, age of ≥65 years was associated with increased long-term mortality for nonshock patients (unadjusted relative risk [RR] 5.23, 95% CI 4.10–6.67, P < .001) and to a lesser degree in patients with cardiogenic shock (unadjusted RR 2.02, 95% CI 1.12–3.65, P = .02). Among cardiogenic shock patients, estimated survival at 1 and 5 years for elderly patients was 38% and 24%, respectively, and in younger patients, 57% and 52%, respectively. When adjusted for confounding variables, elderly noncardiogenic shock patients had significantly increased long-term mortality (adjusted RR 4.38, 95% CI 3.42–5.61, P < .001) compared to younger nonshock patients. In contrast, elderly patients with cardiogenic shock demonstrated a weaker trend toward worse outcomes (adjusted RR 1.80, 95% CI 1.00–3.27, P = .051) compared to younger patients with shock. Conclusions The relationship between age and long-term mortality is stronger among patients who do not develop cardiogenic shock. Advanced age was not found to be as strong a risk factor for survival in patients with cardiogenic shock; comorbidities and less aggressive treatment appear to be the major factors resulting in poor outcomes in the elderly patient with cardiogenic shock.