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It is unknown whether brain affection in myotonic dystrophy type 1 (DM1) and 2 (DM2) is due to neurodevelopmental defects, neurodegeneration or both. Longitudinal imaging studies are missing to date. We performed a longitudinal study to compare changes in cognitive functioning and brain morphology including 16 DM1 (m/f: 6/10, age at baseline 42.48 ± 6.46 years/y, disease duration/DD 13.4 ± 7.5 y), 16 DM2 patients (m/f: 9/7, age 48.49 ± 8.36 y, DD 11.4 ± 9.1 y), and 17 healthy controls (m/f: 9/8, age 50.54 ± 9.78 y). At baseline and 5.45 ± 0.41 y follow-up all subjects underwent neurological and neuropsychological (NP) examinations and 3T-brain magnetic resonance imaging using the identical hard- and software. Diffusion tensor imaging (DTI, Tract Based Spatial Statistics) was conducted to analyse white matter (WM) affection with respect to fractional anisotropy (FA), axial, radial, and mean diffusivity. We used 2-sample t-tests (TT) for group comparisons between patients and controls, and paired t-tests (PT) for longitudinal analyses within each group (p < 0.05, corrected for multiple comparisons). DTI group comparisons (TT) showed almost identical FA reduction patterns at baseline and follow-up. In DM1 compared to controls, FA was reduced along the corpus callosum (CC), association (AF), and projection fibres. In DM2, we found mild affection of CC and forceps minor, and minor additional changes at follow-up. At follow-up, the number of voxels showing FA reduction was particularly increased in DM1 indicating progressive WM disintegrity. Analysing longitudinal differences within each group (PT), we found significant FA changes only in DM1 affecting frontal and posterior AF. These findings were accompanied by a decline in motor tasks in DM1, and a mild deterioration of NP performance in DM1 more than DM2 over time. Our data indicate a mild -however significant-progress of WM affection predominantly in DM1 which might point towards a neurodegenerative component of WM changes.

A considerable proportion of patients with cirrhosis exhibit insomnia, delayed sleep habits, and excessive daytime sleepiness. These have been variously attributed to hepatic encephalopathy and impaired hepatic melatonin metabolism, but the understanding of their pathophysiology remains limited and their treatment problematic. Sleep is regulated by the interaction of a homeostatic and a circadian process. The homeostatic process determines sleep propensity in relation to sleep-wake history, thus the need to sleep increases with the duration of the waking period. The circadian process, which is marked by the 24-hour rhythm of the hormone melatonin, is responsible for the alternation of high/low sleep propensity in relation to dark/light cues. Circadian sleep regulation has been studied in some depth in patients with cirrhosis, who show delays in the 24-hour melatonin rhythm, most likely in relation to reduced sensitivity to light cues. However, while melatonin abnormalities are associated with delayed sleep habits, they do not seem to offer a comprehensive explanation to the insomnia exhibited by these patients. Fewer data are available on homeostatic sleep control: it has been recently hypothesized that patients with cirrhosis and hepatic encephalopathy might be unable, due to excessive daytime sleepiness, to accumulate the need/ability to produce restorative sleep. This review will describe in some detail the features of sleep-wake disturbances in patients with cirrhosis, their mutual relationships, and those, if any, with hepatic failure/hepatic encephalopathy. A separate section will cover the available information on their pathophysiology. Finally, etiological treatment will be briefly discussed. © 2013 by the American Association for the Study of Liver Diseases.