Effect of Yokukansan, a Traditional Herbal Prescription, on Sleep Disturbances in Patients with Alzheimer’s Disease

Objective: Evidence of the effects of Yokukansan (YKS), a traditional herbal medicine, on behavioral and psychological symptoms of dementia (BPSD) has accumulated. As well as BPSD, patients with Alzheimer’s disease (AD) demonstrate poorer sleep quality. Specific sleep disorders such as sleep-disordered breathing and periodic limb movement disorder (PLMD) can be prevalent in the elderly. PLMs are generally considered to produce sleep fragmentation by provoking arousals. This study aimed to examine whether YKS alters polysomnography variables in patients with AD. Methods: Seven patients (3 men and 4 women) with probable AD according to the standard criteria were investigated. Participants were treated with YKS for 4 weeks. The Neuropsychiatric Inventory for the assessment of BPSD, the Mini-Mental State Examination (MMSE) for cognitive function, polysomnography for evaluation of sleep structure and Pittsburgh Sleep Quality Index (PSQI) for subjective sleep quality, and Epworth Sleepiness Scale (ESS) were carried out at baseline and at the end of the treatment. The local institutional review boards approved this study. All patients gave written consent according to institutional guidelines and the tenets of the Declaration of Helsinki. Results: Treatment with YKS resulted in a decreased NPI score, a prolonged total sleep time, a shortened sleep latency, an increased sleep efficiency, and decreased periodic limb movement during sleep. YKS also improved subjective evaluations with PSQI and ESS. Conclusions: YKS was effective for BPSD and sleep disturbances in patients with AD. YKS did not induce daytime somnolence, extrapyramidal signs, or an increased apnea-hypopnea index. *Corresponding author: Hideto Shinno, Professor, Department of Liaison Psychiatry, Kagawa University School of Medicine, 1750-1 Ikenobe, Miki, Kita, Kagawa 7610793, Japan, Tel: +81-87-891-2165; E-mail: [email protected] Received January 27, 2016; Accepted February 29, 2016; Published March 07, 2016 Citation: Shinno H, Ishikawa I, Ando N, Matsumura Y, Horiguchi J, Nakamura Y (2016) Effect of Yokukansan, a Traditional Herbal Prescription, on Sleep Disturbances in Patients with Alzheimer’s Disease. J Alzheimers Dis Parkinsonism 6: 215. doi: 10.4172/2161-0460.1000215 Copyright: © 2016 Shinno H, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. (REM) sleep [4], a reduction in the nocturnal secretion of melatonin [5], and advances of sleep phase [6]. In addition, increases in apneahypopnea and periodic limb movement during sleep (PLMS) are commonly observed in the elderly and often cause the sleep disturbance. PLMS is generally considered to produce poor sleep quality by provoking electroencephalogical arousals or awakenings [7,8]. PLMD is defined as a periodic limb movement (PLM) index of 15 or greater that is associated with an otherwise unexplained sleep-wake complaint. These changes result in sleep fragmentation and poorer sleep quality, and may contribute to sleep disturbances in the elderly. Because these features are noticeable in patients with AD, they are troubled by sleep disturbances in addition to BPSD [3,9]. The prevalence of sleep disturbance in AD has been estimated to be 25% in mild to moderate cases, and about 50% in moderate to severe cases [9]. Sleep problems in AD may be caused by a disrupted rhythm of melatonin production, a greater prevalence of obstructive sleep apnea syndrome, and modified sleep architecture [3]. Changes in sleep architecture in patients with AD Citation: Shinno H, Ishikawa I, Ando N, Matsumura Y, Horiguchi J, Nakamura Y (2016) Effect of Yokukansan, a Traditional Herbal Prescription, on Sleep Disturbances in Patients with Alzheimer’s Disease. J Alzheimers Dis Parkinsonism 6: 215. doi: 10.4172/2161-0460.1000215