While obesity maintained an intense association in the bivar

While obesity maintained an intense association in the bivariate analysis (OR: 9.29), this association was lost in the multivariate analysis, where it was adjusted by neck circumference, which maintained a significant association. This is consistent with the results obtained by Preis et al. [26] in the Framingham study, where they identified neck circumference as a variable with an important correlation to obesity, as well as being associated with cardiovascular risk factors. This finding is relevant to the pathogenesis of OSA, since a high correlation has been identified between an increase in neck circumference and AHI value [27]. There is only one reference in the literature where this cotransport of Extreme sleep apnoea is distinguished from the other subgroups of severe sleep apnoea [28], on this paper, the only patients who has significant REM rebound were the patients who has AHI>100 on the baseline portion of sleep study. In our population this occurrence was not observed.
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Introduction Mild cognitive impaired (MCI) is viewed as a transitional stage from normal to dementia. Patients affected with this condition have a higher turn-over rate to Alzheimer′s disease (AD) with the average rate of 10–15% annually over 5 year [1]. But which of these patients will evolve to AD? Which of these we have to follow more closely? And in the future, if disease-modifying drugs for AD became available, which patients will be chosen to take these medicines? Maybe the answer is in the comorbidities, particularly the neuropsychiatric ones. The definition of this transitional stage was proposed by some authors like the National Institute of Mental Health that, in 1986, proposed the term age-associated memory impairment (AAMI) that characterize memory changes in ageing which were felt to be a manifestation of normal cognition [2]. But the most used concept is the one proposed by Petersen in 2004 [3]. The essential features of these criteria for MCI include: (i) memory complaint usually corroborated by an informant, (ii) objective memory impairment for age, (iii) essentially preserved general cognitive function, (iv) largely intact functional activities, (v) not demented. No particular test or cutoff score is specified. Beyond the definition, the author has been proposed clinical subtypes of MCI. The criteria described define the amnestic MCI subtype (aMCI) which is used for subjects who have memory impairment. If no memory impairment is present then the subject has non amnestic MCI (naMCI). After that, subject is classified in aMIC-single domain or naMCI-single domain if only a single domain (in case of aMIC is memory) is impaired or aMCI-multiple domain or naMCI-multiple domain if multiple domains are impaired (in aMCI smooth muscle must be included memory). The most typical MCI patient is one who has memory impairment beyond what is expected to be normal for age but is relatively intact in other cognitive domains and this impairment is no sufficient severity to constitute dementia [3]. The specific transition between normal ageing and MCI can be quite subtle and the distinction between MCI and very early dementia can also be challenging. Thus, attempts for a combination of measures, clinical features, neuropsychological testing, biomarkers and neuroimaging may be the key to a more accurate diagnosis. Among clinical features, the neuropsychiatric symptoms have been extensively studied. The prevalence of these symptoms in MCI patients is around 50% while at subjects with normal cognition is approximately 25% [4,5]. Between neuropsychiatric symptoms the most common are apathy (11.7–68%), depression/dysphoria (20–56%), sleeping problems (18.3–56%) and anxiety (14.1–54%) [4–7]. The reported prevalence for subjects with normal cognition for apathy (0–4.8%), depression (11–16%), sleeping problems (10.9–23%) and anxiety (5.0–26.7%) is lower than for MCI individuals [4,7]. Although these symptoms are common in subjects with MCI it is uncertain if they can predict AD in this population, as a biomarker. The studies that try to answer this question found contradictory results for the relationship affective symptoms and AD [8–13]. Anyway, in any elderly patients with neuropsychiatric symptoms, we should not overlook the possibility of underlying cognitive impairment.