Sleep in Frontotemporal Dementia is Equally or Possibly More Disrupted, and at an Earlier Stage, When Compared to Sleep in Alzheimer's Disease

Article type: Research Article

Authors: Bonakis, Anastasios^{a; b; d; 1} | Economou, Nicholas-Tiberio^{a; b; *; 1} | Paparrigopoulos, Thomas^b | Bonanni, Enrica^c | Maestri, Michelangelo^c | Carnicelli, Luca^c | Di Coscio, Elisa^c | Ktonas, Periklis^b | Vagiakis, Emmanouil^d | Theodoropoulos, Panagiotis^b | Papageorgiou, Sokratis G.^{a; e}

Affiliations: [a] University of Athens Medical School, Department of Neurology, 1^st Neurological Clinic, Eginition Hospital, Athens, Greece | [b] University of Athens Medical School, Sleep Study Unit, Eginition Hospital, Athens, Greece | [c] Department of Neurosciences, University of Pisa, Pisa, Italy | [d] Critical Care and Pulmonary Services, Center of Sleep Disorders, Evangelismos Hospital, Athens, Greece | [e] University of Athens Medical School, Department of Neurology, 2^nd Neurological Clinic, ATTIKON University General Hospital, Haidari, Athens, Greece

Correspondence: [*] Correspondence to: Nicholas-Tiberio Economou, M.D., University of Athens Medical School, Sleep Study Unit, Eginition Hospital, 74 Vas. Sofias Avenue, 11528 Athens, Greece. Tel.: +30 2107289324; E-mail: nt_economou@yahoo.it.

Note: [1] These authors contributed equally to this manuscript.

Abstract: Background:Conversely to other neurodegenerative diseases (i.e., Alzheimer’s disease, AD), sleep in frontotemporal dementia (FTD) has not been studied adequately. Although some evidence exists that sleep-wake disturbances occur in FTD, very little is known regarding sleep macrostructure and/or primary sleep disorders. Objective:To investigate these issues in this population and compare them to similar issues in AD and in healthy elderly (HE). Methods:Twelve drug-naïve behavioral-variant FTD (bvFTD) patients (7 men/5 women) of mean age 62.5 ± 8.6 years were compared to seventeen drug-naïve AD patients (8 men/9 women) of mean age 69.0 ± 9.9 years and twenty drug-naïve HE (12 men/8 women) of mean age 70.2 ± 12.5 years. All participants were fully assessed clinically, through a sleep questionnaire, an interview, and video-polysomnography recordings. Results:The two patient groups were comparably cognitively impaired. However, compared to FTD patients, the AD patients had a statistically significant longer disease duration. Overall, the sleep profile was better preserved in HE. Sleep complaints did not differ considerably between the two patient groups. Sleep parameters and sleep macrostructure were better preserved in AD compared to FTD patients, regardless of primary sleep disorders, which occurred equally in the two groups. Conclusions:With respect to AD, FTD patients had several sleep parameters similarly or even more affected by neurodegeneration, but in a much shorter time span. The findings probably indicate a centrally originating sleep deregulation. Since in FTD patients sleep disturbances may be obvious from an early stage of their disease, and possibly earlier than in AD patients, physicians and caregivers should be alert for the early detection and treatment of these symptoms.

Keywords: Alzheimer's disease, dementia, frontotemporal dementia, sleep

DOI: 10.3233/JAD-122014

Journal: Journal of Alzheimer's Disease, vol. 38, no. 1, pp. 85-91, 2014