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

Abstract

We investigated whether a self-rated anosognosia score can be an indicator for progression of brain atrophy in patients with amyotrophic lateral sclerosis (ALS). Scores for 16 patients were compared with the ventricular areas of the bilateral anterior and inferior horns measured on x-ray computed tomography. Longitudinal enlargement was expressed as a monthly increase in size: (ventricular size at the initial scan – ventricular size at the follow-up scan)/scan interval (months). The anosognosia scores ranged from –4 to 3 and 3–18 in patients with and without frontotemporal lobar degeneration (FTLD), respectively (p = 0.0011). Anosognosia scores were significantly correlated with sizes of anterior (r = 0.704, p = 0.0016) and inferior (r = 0.898, p < 0.0001) horns. In non-demented patients for whom follow-up CT scans were available (n = 7), the scores were significantly correlated with the longitudinal increase in inferior horn size (r = 0.754, p = 0.0496), but not with that of anterior horn size (r = –0.166, p = 0.7111). In conclusion, anosognosia in ALS is associated with greater anterior and inferior horn sizes, reflecting frontotemporal lobar atrophy. Moreover, mild anosognosia in ALS patients without FTLD may predict impending inferior horn enlargement, reflecting medial temporal atrophy.