We prospectively studied the relationship between serum creatinine and survival among 492 elderly subjects admitted for stroke and monitored for a mean period of 18 months post-stroke. In multivariate proportional hazards models, serum creatinine remained an independent predictor of mortality (P = 0.0001) after accounting for other important predictors such as level of consciousness. Mini-Mental State Score, age, leucocyte count, presence of heart disease, diabetes, heart failure, atrial fibrillation and use of cardiovascular medication. This association between elevated serum creatinine and mortality was also found in patient subgroups with CT-proven infarction and intracerebral haematoma. It is concluded that serum creatinine is an independent predictor of survival after stroke. Further studies are required to confirm this relationship and to elucidate the underlying mechanism.