Curvilinear Relationship Between Age and Post-Stroke Fatigue among Patients in the Acute Phase following First-Ever Stroke

Abstract

Introduction: Fatigue is a common complaint after stroke and may be assumed to be related to older age. Contradictory findings on the relationship between age and post-stroke fatigue have been reported in the rehabilitation phase, but no studies have described their relationship in the acute phase. The aim of this study was to explore the relationships among fatigue, age, and other socio-demographic and clinical factors during the acute phase following stroke. Methods: The sample included 115 patients (ages 29 to 91 years) with first-ever stroke admitted to two hospitals in Norway in 2007 and 2008. Data were collected from medical records and face-to-face interviews within 2 weeks of hospital admission. Measures included the Fatigue Severity Scale, SF-36A Physical Functioning Scale, Beck Depression Inventory-II, Barthel Index and Pittsburgh Sleep Quality Index. Pre-stroke fatigue was defined as fatigue lasting longer than three months before the stroke. Analyses included age group comparisons and hierarchical linear regression. Results: The relationship between age and fatigue was weak and U-shaped rather than linear, with the youngest ( 75 years) groups reporting higher levels of post-stroke fatigue. The effect of age on poststroke fatigue remained significant after controlling for gender, work status, pre-stroke fatigue, physical functioning, sleep disturbance, and comorbidity, but was attenuated after controlling for depressive symptoms. Conclusion: Although post-stroke fatigue in the acute phase was more severe among the youngest and oldest groups, age only explained a small proportion of post-stroke fatigue variability. Clinical factors, such as pre-existing fatigue, physical functioning, and particularly mood are likely more important explanations for post-stroke fatigue than age. Since fatigue may impact the patient’s ability to participate in rehabilitation, clinicians should pay attention to fatigue and its co-existing factors during the acute phase. Evidence-based interventions for managing post-stroke fatigue and improving rehabilitation outcomes are warranted.