Strokes in the Elderly – Higher Acute and 3-Month Mortality – An Explanation

Abstract

Aim: Stroke is common in older people. The objective of the study was to determine if older stroke patients have a higher mortality and disability compared with younger patients for comparable stroke severity and pathology and whether there is an explanation for the difference. Methods: A prospective study was undertaken in 296 consecutive patients admitted with acute stroke. Patients were studied for neurological features, pre-stroke functional disability, severity of stroke defined by stroke syndromes and pathology of stroke on CT scans (202 patients). Post-stroke disability was defined according to the functional status within 72 h of admission. A record was made of the intercurrent illness while the patients were in acute wards and of the risk factors. Patients were dichotomised into two age groups: younger group – up to 75 years (163 patients) and older group – over 75 years (133 patients). Outcome was measured according to (1) discharge status from acute wards, i.e., dead or alive, and (2) mortality at 3 months. Results: Although there was no significant difference in severe clinical stroke syndromes (p = 0.72), CT scan features (p = 0.68) and pyrexia (0.38) between the two age groups, the older patients had significantly more disabling strokes as defined on Barthel Index (p = 0.015) and a higher mortality in the acute phase (p < 0.01) and at 3 months (p = 0.001). The older stroke patients had more severe pre-stroke disability (p < 0.001) and more severe neurological impairment for similar stroke severity and pathology. Early mortality was more influenced by pre-stroke global health than age whereas 3-month mortality was influenced by age to the exclusion of all other known prognostic factors. Conclusion: The older stroke patients have more disabling stroke and an increased mortality for a similar spectrum of stroke severity and pathology. The explanation for higher mortality of the older patients is the poor pre-stroke health and higher immediate post-stroke disability.