The physiology of sleep wakefulness cycle may be affected as

The physiology of sleep-wakefulness melatonin receptor agonists may be affected as a result of changes in ovarian hormone synthesis. The menopause and the reduction in the availability of endogenous estradiol, that occur within the climacteric, have been considered risk factors for SD. The effect could be directly influenced by changes in the steroid profile, as a result of variations in body temperature by the presence of hot flashes, circadian rhythm disturbances or higher reactivity to stress [11–14].
There is controversy about whether severity criteria should be assessed in the presence of insomnia or in the functional impairment that this could entailed, which always should be considered due to they could affect the quality of life further than sleep disturbances [15]. The diagnostic method of SD is the polysomnography, considered the gold standard; however, it has some limitations due to it does not evaluate quality of sleep and the impact of SD on daily activities. In additionally, to carry out the procedure is necessary to have a quiet room, as close as possible to the home address, where the patient could sleep and another room where the necessary sleep equipment could be installed [16].
Sleep scales are tools to identify, in a subjective way, SD [9,17]. They offer advantages as easy application and interpretation and the availability to study different disorders [5,18]. These scales must have been validated in populations and checked in the age groups. Since the high prevalence of SD in climacteric is necessary to know the differences among scales that are available to study adequately these women, and to establish the deterioration of the quality of sleep or the presence of any different types of SD [18–21]. The aim is to identify and to describe the different scales that have been used to assess SD in climacteric.

Methods

Discussion
The SD are very important problems with many expressions, complex etiology with associated factors [6,39]. There are many scales that have been developed and validated in several areas of the health; they are available to analyze the sleep behavior and to establish subjectively the presence of SD. To study the general population in specific groups like elderly, children and adolescent patients with dementia and other diseases has been proposed.
The most widely used scales to study climacteric are Insomnia Severity Index (ISI), Athens Insomnia Scale (AIS) and Pittsburgh Quality of Sleep Index (PSQI), with validation in several countries and languages, which make them attractive to assess the prevalence and factors associated with SD. The first two of them allow setting aspects specifically related to insomnia, whose prevalence increases in postmenopausal women, increasing in 60% while in premenopausal women 40%. The four major causes proposed to explain the poor quality of sleep are: sleep disruption associated with hot flashes, increase of sleep apnea, mood disorder and inadequate sleep hygiene leading to chronic insomnia [40].
The PSQI was developed to provide a reliable, valid and standardized measure of quality of sleep, to discriminate between “good” and “poor” sleepers, to procure an easy index to use in patients, clinicians and researchers to understand and to provision a brief, clinical and useful assessment of a variety of sleep disturbances that might affect quality of sleep. It has been widely used in melatonin receptor agonists climacteric and it is a proper tool to be applied [5,9,28].
The Insomnia Severity Index, Athens Insomnia Scale, Pittsburgh Quality of sleep Index (PSQI) and Basic Nordic Sleep Questionnaire (BNSQ) have been used to check modifications in the prevalence of SD in women with hormonal therapy for the treatment of menopause symptoms, demonstrating its efficacy in these scenes [5,9,18,36].
The PSQI could be difficult to apply as a self-administered instrument in patients with low educational levels. The internal consistency determined by Cronbach\’s alpha was appropriated for the 19 items and 7 components. The scores of the items, the components and the total value remained stable during the time of Test-retest. The cutoff point of five has been used to define the population with poor quality of sleep [25].