Early poststroke clinically significant fatigue predicts functional independence: a prospective longitudinal study

Fatigue is common among stroke patients. This study determined the prevalence of fatigue among long-term survivors after stroke and what impact fatigue had on various aspects of daily life and on survival. This study was based on Riks-Stroke, a hospital-based national register for quality assessment of acute stroke events in Sweden. During the first 6 months of 1997, 8194 patients were registered in Riks-Stroke, and 5189 were still alive 2 years after the stroke. They were followed up by a mail questionnaire, to which 4023 (79%) responded. Patients who reported that they always felt depressed were excluded. To the question, "Do you feel tired?" 366 (10.0%) of the patients answered that they always felt tired, and an additional 1070 (29.2%) were often tired. Patients who always felt tired were on average older than the rest of the study population (74.5 versus 71.5 years, P<0.001); therefore, all subsequent analyses were age adjusted. Fatigue was an independent predictor for having to move into an institutional setting after stroke. Fatigue was also an independent predictor for being dependent in primary activities of daily living functions. Three years after stroke, patients with fatigue also had a higher case fatality rate. Fatigue is frequent and often severe, even late after stroke. It is associated with profound deterioration of several aspects of everyday life and with higher case fatality, but it usually receives little attention by healthcare professionals. Intervention studies are needed.

Subjective fatigue, defined as a feeling of early exhaustion developing during mental activity, with weariness, lack of energy and aversion to effort, remains virtually unstudied in patients with stroke, bur recent surveys suggest that it is a major, commonly overlooked, stroke sequela. While the few existing series did not show significant correlations between fatigue and stroke severity, lesion location, cognitive and neurological impairment and depression, recent neurobehavioral studies have highlighted an association between fatigue and brainstem and thalamic lesions. This suggests that fatigue may be linked to the interruption of neural networks involved in tonic attention, such as the reticular activating system. In fact, several subtypes of fatigue may develop after stroke, in connection with cognitive sequelae, neurological impairment, psychological factors and sleep disorders. A challenge is to identify and delineate these different subtypes and to distinguish them from mood disorders, which frequently coexist. We emphasize the concept of ‘primary’ poststroke fatigue, which may develop in the absence of depression or a significant cognitive sequela, and which may be linked to attentional deficits resulting from specific damage to the reticular formation and related structures involved in the subcortical attentional network. In the patients with excellent neurological and neuropsychological recovery, poststroke fatigue may be the only persisting sequela, which may severely limit their return to previous activities. The recognition of poststroke fatigue may be critical during recovery and rehabilitation after stroke.

The purpose of this study was to compare disability and quality of life as measured by the Stroke Impact Scale (SIS) of stroke patients deemed recovered (Barthel Index > or =95) with 2 stroke-free populations of community-dwelling elderly. Eighty-one stroke patients who participated in the Kansas City Stroke Registry and achieved a Barthel Index of > or =95 at 3 months after stroke and 246 stroke-free subjects enrolled in the Community Elders Study were enrolled in this study. The Community Elders Study group was further divided into 2 groups, those recruited from the Department of Veterans Affairs Health System (VA) and a those from a local health maintenance organization (HMO). Stroke patients were administered the SIS approximately 90 days after stroke, and the stroke-free community dwellers were administered a version of the SIS adapted for nonstroke subjects, the Health Impact Scale (HIS). A general linear model was used to examine differences in health outcomes measured by the SIS or HIS between the KCSR stroke patients and VA and HMO community-dwelling elders after controlling for medical comorbidities and demographics. Kansas City Stroke Registry participants were significantly older than the community study groups (P=0.0052). Selected medical conditions were similar among the 3 study groups. Old age and a history of diabetes mellitus were more likely to be associated with more deficits and poor quality of life. In stroke patients deemed recovered, stroke still affected hand function, activities and independent activities of daily living, participation, and overall physical function compared with the stroke-free community dwellers in the HMO health system even after adjustment for age and diabetes status. Stroke-free community dwellers in the VA health system also had worse social participation than the stroke-free community dwellers in the HMO health system. Research and clinicians have consistently underestimated the impact of stroke with the Barthel Index. This has major implications for the design of therapeutic trial designs and adequate assessments of social and economic sequelae of stroke.