INTRODUCTIONThe aging of the population is a worldwide phenomenon, highlighting the significant increase in the population aged 70 years and older. In 2009, the results of the National Household Sample Survey indicated a total of 11.3 million in this age group. The decrease of the children and youth and the consequent increase in adult population and elderly is related to the continued decline in the fertility and mortality rate combined with an increased life expectancy (1) .Simultaneously, the most prevalent diseases among elderly are also changing, with a sharp decline in the morbidity and mortality from infectious and contagious diseases and an increase in chronic non-communicable diseases (CNCDs) (2) . With aging, the probability of acquiring CNCD increases while functional capacity and body reserves decrease, leading to a greater susceptibility to these diseases and other health problems (3) . Thus, there may be a direct association between the demographic and epidemiological transition.According to the Brazilian Institute of Geography and Statistics, in 2008, the most prevalent diseases in seniors were: high blood pressure (53.3%), back pain (35.1%), rheumatoid arthritis or rheumatism (24.2%), heart diseases (17.3%), diabetes mellitus (16.1%) and other diseases (20.9%) (1) . The CNCDs may result in losses in the overall health and functionality of the elderly, negatively affecting their quality of life, including the standard and quality of sleep (4) .Aging by itself can bring changes in the usual pattern of sleep, such as quantitative reduction of deep sleep stages and increase in the light sleep stages, nocturnal sleep disruption, increased sleep onset latency, reduced duration of nocturnal sleep, and more frequent transitions between the sleep stages during the night. The prevalence of sleep-disordered breathing and disorders related to increased nocturnal myoclonic activity are also more common over 60 years of age, so that the complaints of insomnia symptoms are most frequent among the elderly (4)(5) .There are four essential symptoms for the diagnosis of sleep disorders and insomnia: difficulty falling asleep, difficulty staying asleep, early awakening and non-restorative sleep. Various international classification manuals for sleep disorders shared these criteria, including the Research Diagnostic Criteria of the American Academy of Sleep Medicine (RDC), the International Classification of Sleep Disorders (ICSD-2) and the International Classification of Diseases Organization of the World Health Organization (ICD 10) (6) .Changes in sleep patterns and insomnia symptoms in seniors may occur as a consequence of CNCDs. Other prevalent diseases in this age group may influence sleep quality, among them, we highlight depression, bladder weakness and neurological problems, such as Parkinson's disease and stroke (7)(8) . In addition, lifestyles changes that are often linked to aging, such as retirement and widowhood, may contribute to these sleep modifications (9) .Among the examples of CNCDs, rheumatoid ar...