Subjective sleep problems in Huntington's disease: A pilot investigation of the relationship to brain structure, neurocognitive, and neuropsychiatric function

Subjective reports of sleep disturbance are a common feature of Huntington's disease (HD); however, there is limited research investigating the relationship between sleep problems with changes in brain and behaviour. This study aimed to investigate whether subjective reports of sleep problems in HD are associated with brain volume, neurocognitive decline, and neuropsychiatric symptoms. This retrospective pilot study used brain volume, neurocognitive and neuropsychiatric data from premanifest (pre-HD) and symptomatic HD (symp-HD). Subjective sleep problem was measured using the sleep item of the Beck's Depression Inventory-II (BDI-II). Pre-HD individuals reporting sleep problems had significantly poorer neuropsychiatric outcomes compared to those not reporting sleep problems. In the symp-HD group, those with sleep problems had significantly accelerated thalamic degeneration and poorer neuropsychiatric outcomes compared to those without sleep problems. There was no relationship between subjective sleep problems and neurocognitive measures. These findings suggest an association between subjective sleep disturbance, neuropathology, and development of neuropsychiatric symptoms in HD. Further studies using quantitative EEG-based monitoring of sleep in HD and changes in the brain and behaviour will be necessary to establish the causal nature of this relationship.