Ischemic stroke patients with prestroke dependency: Characteristics and long-term prognosis

This paper aims at examining the clinical characteristics of ischemic stroke patients with different levels of prestroke functional dependency, their long-term outcome, and determinants of five-year mortality.

We describe demographics, comorbidity, treatment, as well as long-term mortality, and functional status of 5899 prestroke-dependent ischemic stroke patients stratified by dependency level and compared to a concurrent cohort of 14 148 prestroke-independent patients. The study was based on 2016 survey data from Riksstroke, the Swedish national stroke register, and patients were followed up at three months, 12 months, and either at three or five years. We used Cox regression for mortality predictor analysis and multiple imputation was performed to minimize bias from loss to follow-up.

With increasing level of prestroke dependency, comorbidity burden was higher, drug prescription lower, and prognosis less favorable. At three years, the proportion that had died or deteriorated were 82.6%, 87.5%, and 86.3% in moderate, moderately severe, and severe dependency, respectively. In moderate dependency, prognosis was relatively favorable: Three-month mortality was half of that seen in severe dependency (25.3% versus 49.6%). Differences in overall outcome between groups of varying prestroke functional dependency level were statistically significant (P < .05) at all follow-up time points.

There was great heterogeneity between groups of different level of prestroke dependency; those of moderate dependency had a relatively favorable prognosis. Patients of different prestroke level of dependency need to be addressed separately, and further research is needed characterizing this group and exploring management strategies.