Evidence of a neurologically based "denial of illness" in patients with Huntington's disease

Abstract

Patients diagnosed with Huntington's Disease (HD) commonly show a denial of symptoms and an unawareness of the motoric, cognitive, and emotional changes that accompany this disease. To examine if this denial has a neurological component to it, 19 patients who received a positive diagnosis of HD from the presymptomatic HD clinic at the University of Connecticut Medical School, and 14 consecutive patients referred for neuropsychological testing with nonHD diagnoses, were administered a simple, eight-item self-report test that asked them to rate their cognitive and motoric abilities. Two staff members, both of whom met with the patients and were familiar with the neuropsychological test results, similarly rated the patients' deficits. HD patients were then divided into "high" (HA) vs. "low" (LA) anosognosia groups based on differences between their self-ratings and staff ratings, and given a neuropsychological battery. Correlation's between the two investigators found that the eight-item scale was highly reliable across investigators (R =.89). HD patients were significantly different from controls in their self-rating of their own capabilities in comparison to staff ratings (p <.05). ANOVA found the HA HD patients to be impaired relative to the LA HD group on a number of neuropsychological measures, including the Wisconsin Card Sorting Test and various measures pertaining to visual-spatial ability on the Wechsler Adult Intelligence Scale-Revised. These findings suggest that a component of the "illness denial" that HD patients exhibit, and that traditionally have been attributed to "psychodynamic" factors, likely have a neurological component to them. Implications of these findings for teams who are preparing to provide anosognostic HD patients with positive results regarding their HD workup is discussed.

Unawareness of motor phenoconversion in Huntington disease

“…Possible measures in established HD and in frontotemporal dementia and Alzheimer disease are reported that include an anosognosia rating scale 39 as well as several neuropsychological measures of impairment in the anosognosia group, the Wisconsin Card Sorting Test and tests of visual-spatial ability on the Wechsler Adult Intelligence Scale-revised. Patients with HD studied using the Dysexecutive Questionnaire 40 rated their carer accurately but underrated their own executive dysfunction.…”

"Frontal" Behaviors Before the Diagnosis of Huntington's Disease and Their Relationship to Markers of Disease Progression: Evidence of Early Lack of Awareness

“…Similarly, Hoth et al (14) found that patients with manifest HD had impaired awareness across a range of abilities (e.g., motor, cognition, emotional control) when compared to companion ratings and objective testing. Two other studies (15,16) found significant discrepancies between patient and companion reports on rating scales, which could be interpreted as decreased insight. Taken together, there is a growing body of literature that documents behavioral manifestations of frontal dysfunction in patients diagnosed with HD.…”

Self-Rated Anosognosia Score May Be a Sensitive and Predictive Indicator for Progressive Brain Atrophy in Amyotrophic Lateral Sclerosis: An X-Ray Computed Tomographic Study

“…Scores on the anosognosia scale [8] and CT images were reviewed for 52 patients admitted to our department and diagnosed with ALS over an 8-year period from 2003 to 2010. Diagnosis of ALS was based on El Escorial revised criteria for probable or definite ALS [11] or on autopsy findings.…”

“…In contrast, insight has rarely been studied in amyotrophic lateral sclerosis (ALS) [6]. Recently, we have shown the importance of anosognosia of illness in ALS patients with dementia [7], using the self-rated scale for anosognosia developed by Deckel and Morrison [8] in 1977. This scale is easily completed in a few minutes at the bedside, even for patients with severe ALS.…”