The impact of ageing on stroke subtypes, length of stay and mortality: study in the province of Teruel, Spain

Abstract

Background and purpose: During the last three decades, there have been important advances in the diagnosis and treatment of stroke leading to a decline in mortality rates in western countries. However, the longer life expectancy and the higher proportion of elderly people in the structure of the population may partially counteract this positive trend in stroke-related mortality. The purpose of this study was to analyse the impact of a high ageing index of the population on stroke-related variables such as stroke subtypes, length of hospital stay and mortality from stroke.

Methods: We analysed the data of 1850 consecutive patients with first-ever stroke retrieved from a prospective registry over a period of 8 years (1994-2001) in the province of Teruel, Spain, with two public hospitals in the catchment area. The mean age was 75.5 years (SD: 9.4) and the sex was male in 62% of cases. The variables included in the study were vascular risk factors, stroke subtypes, fatality rate, length of stay and mortality. Mortality was assessed from 1990 to 2000.

Results: Arterial hypertension and atrial fibrillation were the most frequent risk factors, with an observed high frequency of cardioembolic stroke. The mean 28-day case fatality rate was 16.6%, ranging from 11.9% in 1994 to 23.4% in 1999. We found complications in 38% of patients, especially in the elderly. Fatality occurred in 20.3% of elderly subjects (65 or over) in comparison to 7.25% for those younger (Relative risk: 2.8; 95% CI: 1.475.3). Crude mortality rates were higher than for the general population in Spain and ranged from 169 in 1991 to 139/100,000 in 2000 with higher rates for women. However, the age-adjusted mortality rate to the standard European population was 56.6/100,000 (95% CI: 4664) in 1999, which was similar to that found in Spain (61/100,000).

Conclusions: The impact of ageing on case fatality and mortality by stroke was substantial. Whereas mortality by stroke stabilized after decreasing in our province and in Spain in the last decade, fatality rates have significantly increased in our province because of the high proportion of elderly people and to the high rate of post-stroke complications.