To better understand the clinical and laboratory characteristics and to identify risk factor(s) for fatality in elderly patients with dengue hemorrhagic fever (DHF), 66 elderly (age > or = 65 years) and 241 non-elderly adults (age, 19-64 years) with DHF were retrospectively analyzed. Compared with non-elderly adults, elderly individuals had significantly lower incidences of fever (P = 0.002), abdominal pain (P = 0.003), bone pain (P < 0.001), and skin rashes (P = 0.002); higher frequencies of concurrent bacteremia (P = 0.049), gastrointestinal bleeding (P = 0.044), acute renal failure (P = 0.001), and pleural effusion (P < 0.010); higher incidence of prolonged prothrombin time (P = 0.025); lower mean hemoglobin level (P < 0.001); longer hospitalization (P = 0.049); and a higher fatality rate (P = 0.006). Five elderly patients with DHF died. When compared with non-fatal elderly patients with DHF, a significant higher frequency in men (P = 0.019), those with chronic obstructive pulmonary disease (P = 0.008), those with dengue shock syndrome (DSS; P < 0.001), and those with acute renal failure (P < 0.001) was found in the elderly counterparts that died. Multivariate analysis showed that only DSS (odd ratio = 77.33, P = 0.001) was an independent risk factor for fatality in elderly patients.