The evaluation of anosognosia in stroke patients.

BACKGROUND: Anosognosia in stroke patients showed a relevant detrimental effect on the rehabilitation course and patients' quality of life, especially in those with brain injury. Although a number of reliable scales for the assessment of anosognosia in stroke and traumatic brain injury have been developed, at present no single measure fully explores the multifaceted nature of the phenomenon. METHOD: A PubMed search with appropriate terms was carried out in order to critically review the issue. RESULTS: The main dimensions to consider in the investigation of anosognosia in brain-injured patients are (a) awareness of deficit and related functional implications, (b) modality specificity, (c) causal attribution, (d) expectations of recovery, (e) implicit knowledge and (f) differential diagnosis with psychological denial. Time elapsed from stroke, aetiology, laterality, aphasia and clinical complications may influence all these characteristics and must be taken into consideration. Finally, an adequate association of the anosognosia evaluation with other neuropsychological and behavioural aspects is relevant for a modern holistic approach to the patient. CONCLUSIONS: This review is meant to stimulate the development of a new comprehensive assessment procedure for anosognosia in brain injury and particularly in stroke, in order to catch the multidimensionality of the phenomenon and to shape rehabilitation programmes suitable to the specific clinical features of every single patient.

Anosognosia for hemiplegia after stroke is a multifaceted phenomenon: a systematic review of the literature.

Anosognosia is the lack of awareness or the underestimation of a specific deficit in sensory, perceptual, motor, affective or cognitive functioning due to a brain lesion. This self-awareness deficit has been studied mainly in stroke hemiplegic patients, who may report no deficit, overestimate their abilities or deny that they are unable to move a paretic limb. In this review, a detailed search of the literature was conducted to illustrate clinical manifestations, pathogenetic models, diagnostic procedures and unresolved issues in anosognosia for motor impairment after stroke. English and French language papers spanning the period January 1990-January 2007 were selected using PubMed Services and utilizing research words stroke, anosognosia, awareness, denial, unawareness, hemiplegia. Papers reporting sign-based definitions, neurological and neuropsychological data and the results of clinical trials or historical trends in diagnosis were chosen. As a result, a very complex and multifaceted phenomenon emerges, whose variable behavioural manifestations often produce uncertainties in conceptual definitions and diagnostic procedures. Although a number of questionnaires and diagnostic methods have been developed to assess anosognosia following stroke in the last 30 years, they are often limited by insufficient discriminative power or a narrow focus on specific deficits. As a consequence, epidemiological estimates are variable and incidence rates have ranged from 7 to 77% in stroke. In addition, the pathogenesis of anosognosia is widely debated. The most recent neuropsychological models have suggested a defect in the feedforward system, while neuro-anatomical studies have consistently reported on the involvement of the right cerebral hemisphere, particularly the prefrontal and parieto-temporal cortex, as well as insula and thalamus. We highlight the need for a multidimensional assessment procedure and suggest some potentially productive directions for future research about unawareness of illness.