Gamma stimulation improves sleep in Alzheimer’s patients as assessed by continuous actigraphy recordings over six months

Abstract

AbstractBackgroundPrevious work has shown that sleep abnormalities are associated with Alzheimer’s Disease (AD) in multiple ways, including the observation that sleep disruptions precede the onset of cognitive symptoms in AD subjects, and that there is a strong association between disrupted sleep and development and progression of AD (Ju et al, Nat Rev Neurol. 2014 Feb; 10(2): 115‐119, Lim et al, Neurodegener Dis Manag. 2014; 4(5):351‐362). These associations, along with the fact that sleep disturbances can have broad behavioral effects, have led to the suggestion that improving sleep is an important aspect of therapeutic strategies for subjects with AD. In the present study, the long‐term effects of non‐invasive gamma sensory stimulation (Cognito Therapeutics, Inc) on sleep were evaluated in mild to moderate AD patients.MethodActivity of mild to moderate AD patients was monitored continuously with a wrist worn actigraphy watch, and data was collected during a 6‐month period. Patients were randomized to receive either 40Hz non‐invasive audio‐visual stimulation or placebo treatment. The durations of rest periods during the night was estimated from the actigraphy data and the distributions of these durations were compared between the first 3 months of the treatment period and the second 3 months of the treatment period in both cohorts.ResultAnalysis of the actigraphy data revealed that sensory‐evoked gamma stimulation improved sleep as assessed by continuous actigraphy recordings. In the active treatment group, the distribution of rest‐durations was shifted towards longer durations in the second 3 months compared with the first 3 months. In the placebo group the reverse was observed: the distribution of rest periods was shifted to shorter durations compared in the second 3 months to the first 3 months. The overall total sleep‐time at night was unaltered in either group.ConclusionGamma stimulation therapy over six months demonstrated an improvement in sleep quality and increased night‐time restful periods as assessed by continuous actigraphy recordings.