A Population-Based Study of the Prevalence of Fatigue After Transient Ischemic Attack and Minor Stroke

Abstract

Fatigue is common after stroke and can be attributable to the increased physical effort associated with severe neurological deficits; however, its presence in those with little motor deficit raises the possibility of confounding by other factors, such as comorbidity, anxiety, and medication. To control for such factors and determine the extent of stroke-specific fatigue, we compared patients with minor stroke who had little or no residual neurological deficit with patients with TIA; both groups had undergone similar investigations and treatment. The prevalence of fatigue 6 months after TIA or minor stroke was assessed in consecutive patients using the Chalder fatigue scale in a population-based incidence study (Oxford Vascular Study). Patients were included if they were independent in self-care Barthel Index (>or=18/20) and without major cognitive impairment (Mini-Mental State Examination >or=24/30). Stroke severity at baseline was assessed with the National Institute of Health Stroke Scale (NIHSS). Other potential causes of fatigue were assessed including anxiety, depression, recent life events, medication, and abnormalities in biochemistry or hematologic tests. Seventy-six participants had minor stroke (mean age, 74.1 years; 42 men) and 73 had TIA (mean age, 72.5 years; 40 men). At 6-month follow-up, median Barthel Index score was 20 (interquartile range, 20-20) in both groups. However, fatigue was more common after stroke than TIA (56% vs 29%; OR, 3.14; 95% CI, 1.51-6.57; P=0.0008). This difference was present both in patients with modified Rankin score of 0 at 6 months (23.8% vs 10.3%) and patients with modified Rankin score >or=1 (69.2% vs 48.6%), and remained more frequent in stroke patients after adjustment for potential confounders. Within the group of patients with stroke, the prevalence of fatigue increased with initial stroke severity (87% NIHSS >or=4 vs 48% NIHSS <or=3; P=0.0087); however, stroke patients with initial NIHSS of 0 were still more fatigued than patients with TIA (57% vs 29%; P=0.015). The prevalence of fatigue after minor stroke is higher than after TIA, suggesting that it is not simply a consequence of the stress of a recent acute cerebral event, comorbidity, medication, or other potential confounders. The high levels of fatigue in stroke patients without neurological impairment suggest it has a central origin rather than being the result of increased physical effort required after stroke.