Hábitos e problemas do sono das crianças dos 2 a 10 anos

RESUMO: Enquadramento: O sono é cada vez mais reconhecido como um fator determinante na Saúde Infantil porque, quando desadequado, pode ter consequências na regulação emocional e do comportamento, nas funções cognitivas, no rendimento académico, na regulação do peso e no risco de lesões acidentais. Os hábitos e problemas do sono das crianças portuguesas não se encontram ainda bem caracterizados. Este conhecimento é importante para o desenvolvimento da investigação e para a promoção da saúde nesta área. Objetivos: Adaptar e validar o Children's Sleep Habits Questionnaire (CSHQ) para a cultura portuguesa; Caracterizar os hábitos de sono de uma amostra de crianças dos 2 aos 10 anos tendo em vista a obtenção de dados de referência; Estimar a prevalência dos problemas do sono na perspetiva dos pais; Avaliar se existem diferenças nos hábitos e problemas do sono entre as regiões de média-alta e baixa densidade populacional; Identificar potenciais consequências dos problemas do sono. Métodos: Foi realizado um estudo transversal, descritivo e correlacional. A versão portuguesa do questionário (CSHQ-PT) foi desenvolvida de acordo com as orientações previamente publicadas e validada numa amostra de 315 crianças dos 2 aos 10 anos. Para o estudo dos hábitos e problemas do sono, o CSHQ-PT foi distribuído aos pais de 2257 crianças recrutadas em 17 zonas de agrupamentos escolares (15 escolhidos de forma aleatória) das áreas da Grande Lisboa, Península de Setúbal e Alentejo, compreendendo zonas litorais e do interior, e de alta, média e baixa densidade populacional. Foram obtidos 1450 (64%) questionários válidos. Resultados: O CSHQ-PT mostrou propriedades psicométricas semelhantes às das versões de outros países e adequadas para a investigação. A avaliação dos hábitos de sono nos dias de semana mostrou que as crianças se deitam, em média, pelas 21h 44m (DP 38 min.). A necessidade da companhia dos pais para adormecer diminui com a idade, ocorrendo em 49% das crianças aos 2-3 anos e 10% aos 9-10 anos. O hábito de adormecer a ver televisão foi descrito em 15,8% das crianças. O tempo total de sono diário diminui com a idade, com uma diferença mais marcada dos 2 para os 3 anos e dos 3 para os 4 anos, quando a sesta se torna menos frequente. No fim de semana, 25% das crianças dormia pelo menos mais uma hora. As diferenças nos hábitos de sono entre regiões de média-alta e de baixa densidade populacional foram reduzidas, sem reflexo na duração média do sono. Considerando valores de referência de outros países, verificou-se que 10% das crianças estudadas tinha uma duração do sono dois desvios-padrão abaixo da média esperada para a idade. A prevalência dos problemas do sono na perspetiva dos pais foi de 10,4%, sem diferenças significativas entre classes etárias, subgrupos de nível educacional dos pais, nem entre zonas de média-alta e baixa densidade populacional. Estes problemas do sono mostraram-se associados, sobretudo, à duração do sono insuficiente, resistência em ir para a cama, dificuldade em adormecer sozinho, despertares noturnos frequentes e ocorrência de parassónias. A baixa prevalência de problemas do sono identificados pelos pais contrasta com cotações elevadas no CSHQ-PT que traduzem comportamentos-problema mais frequentes, que são bem aceites por alguns pais. O Índice de Perturbação do Sono foi mais elevado nas famílias com menor nível educacional. Em análise multivariada mostraram valor preditivo para a sonolência diurna: o tempo total de sono diário, a diferença da duração do sono noturno durante a semana e no fim de semana, a frequência de algumas parassónias e o hábito de adormecer a ver televisão. O rendimento escolar mostrou associação com os problemas do sono, que são mais frequentes nas crianças com dificuldades escolares e hiperatividade/problemas de atenção. A relação entre estas variáveis é complexa. Conclusões: Este estudo mostrou que os problemas comportamentais do sono e a privação de sono são frequentes na população estudada. Estes problemas têm consequências, uma vez que correspondem a uma frequência mais elevada de sintomas de sonolência diurna, por comparação com outros países. Perante este cenário, é muito importante reforçar a promoção de hábitos de sono saudáveis e continuar a estudar as consequências do sono desadequado nas crianças portuguesas. -----------ABSTRACT:Framework: Sleep is increasingly being recognized as important to Child Health, for inadequate sleep may impact behavioral and emotional regulation, cognitive functions, academic performance, weight regulation and the risk of accidental injuries. The sleep habits and sleep problems of Portuguese children are not well characterized. This knowledge is important to support further studies and health promotion actions. Objectives: Develop and validate a Portuguese version of the Children's Sleep Habits Questionnaire (CSHQ-PT); Characterize the sleep habits and problems in a sample of Portuguese children from the ages of 2 to 10 for future reference; Estimate the prevalence of parent-defined sleep problems; Assess whether there are differences in sleep habits and problems between regions of medium-high and low population densities; Identify potential consequences of sleep problems. Methods: We conducted a cross-sectional, descriptive and correlational study. The Portuguese version of the questionnaire (CSHQ-PT) was developed according to published guidelines and validated in a sample of 315 children from 2 to 10 years old (y.o.). In order to study sleep habits and problems we delivered the CSHQ-PT to 2257 children recruited from 17 school districts (15 were chosen randomly) in areas with low, medium and high population densities, including coastline and inland regions. 1450 (64%) valid questionnaires were obtained. Results: The CSHQ-PT demonstrated psychometric properties that were similar to the versions from other countries and adequate for research. The evaluation of sleep habits showed that on schooldays children go to bed, on average, at 21h 44m (SD 38 min.). The need of having the parent in the room at bedtime decreases with the age of the child, occurring in 49% of children with 2-3 y.o. and 10% of children between 9 and 10 y.o. The habit of going asleep while watching TV was reported in 15,8% of the children. Total sleep time diminishes with the age of the child, having a major decrease from 2 to 3 y.o. and from 3 to 4 y.o., along with less frequent naps. During the weekend, 25% of the children sleep at least one extra hour. Considering reference values from other series, we found that 10% of the children had a sleep duration two standard deviations below the mean for the age. The differences in sleep habits between regions of medium-high and low population densities are few, and there are no differences in average sleep durations. The prevalence of parent-defined sleep problems was 10.4%. There were no significant differences between age classes, parent education subgroups or between regions of medium-high and low population densities. These sleep problems were associated with insufficient sleep duration, bedtime resistance, difficulty in falling asleep alone, frequent night awakenings and the occurrence of parasomnias. The low prevalence of parent-defined sleep problems contrasts with high CSHQ scores meaning that problematic behaviors are more frequent, but acceptable to some parents. The Sleep Disturbance Score was higher in families with a lower educational level. In multivariate analysis, the following factors predicted the daytime somnolence score: total sleep time, the difference in night sleep duration between the weekend and school days, the frequency of some parasomnias and the habit of falling asleep while watching TV. School achievement showed a negative correlation with the sleep problems, which are more frequent in children with school difficulties and hyperactivity/attention problems. The relationship between these variables is complex. Conclusions: This study evidenced that behavioral sleep problems and sleep deprivation are common in our population. These sleep problems have consequences as they correspond to more symptoms of excessive daytime somnolence comparing to other countries. Therefore, we reinforce the importance of promoting healthy sleep habits and further study the consequences of inadequate sleep in Portuguese children.

Help-seeking for 'memory loss' by older adults in India : patient, caregiver and health providers' perspectives

ABSTRACT: Background. In India, prevalence rates of dementia and prodromal amnestic Mild Cognitive Impairment (MCI) are 3.1% and 4.3% respectively. Most Indians refer to the full spectrum of cognitive disorders simply as ‘memory loss.’ Barring prevention or cure, these conditions will rise rapidly with population aging. Evidence-based policies and practices can improve the lives of affected individuals and their caregivers, but will require timely and sustained uptake. Objectives. Framed by social cognitive theories of health behavior, this study explores the knowledge, attitudes and practices concerning cognitive impairment and related service use by older adults who screen positive for MCI, their primary caregivers, and health providers. Methods. I used the Montreal Cognitive Assessment to screen for cognitive impairment in memory camps in Mumbai. To achieve sampling diversity, I used maximum variation sampling. Ten adults aged 60+ who had no significant functional impairment but screened positive for MCI and their caregivers participated in separate focus groups. Four other such dyads and six doctors/ traditional healers completed in-depth interviews. Data were translated from Hindi or Marathi to English and analyzed in Atlas.ti using Framework Analysis. Findings. Knowledge and awareness of cognitive impairment and available resources were very low. Physicians attributed the condition to disease-induced pathology while lay persons blamed brain malfunction due to normal aging. Main attitudes were that this condition is not a disease, is not serious and/or is not treatable, and that it evokes stigma toward and among impaired persons, their families and providers. Low knowledge and poor attitudes impeded help-seeking. Conclusions. Cognitive disorders of aging will take a heavy toll on private lives and public resources in developing countries. Early detection, accurate diagnosis, systematic monitoring and quality care are needed to compress the period of morbidity and promote quality of life. Key stakeholders provide essential insights into how scientific and indigenous knowledge and sociocultural attitudes affect use and provision of resources.

Contribution to drug discovery and development for tauopathies using yeast as a model

This work aimed to contribute to drug discovery and development (DDD) for tauopathies, while expanding our knowledge on this group of neurodegenerative disorders, including Alzheimer’s disease (AD). Using yeast, a recognized model for neurodegeneration studies, useful models were produced for the study of tau interaction with beta-amyloid (Aβ), both AD hallmark proteins. The characterization of these models suggests that these proteins co-localize and that Aβ1-42, which is toxic to yeast, is involved in tau40 phosphorylation (Ser396/404) via the GSK-3β yeast orthologue, whereas tau seems to facilitate Aβ1-42 oligomerization. The mapping of tau’s interactome in yeast, achieved with a tau toxicity enhancer screen using the yeast deletion collection, provided a novel framework, composed of 31 genes, to identify new mechanisms associated with tau pathology, as well as to identify new drug targets or biomarkers. This genomic screen also allowed to select the yeast strain mir1Δ-tau40 for development of a new GPSD2TM drug discovery screening system. A library of unique 138 marine bacteria extracts, obtained from the Mid-Atlantic Ridge hydrothermal vents, was screened with mir1Δ-tau40. Three extracts were identified as suppressors of tau toxicity and constitute good starting points for DDD programs. mir1Δ strain was sensitive to tau toxicity, relating tau pathology with mitochondrial function. SLC25A3, the human homologue of MIR1, codes for the mitochondrial phosphate carrier protein (PiC). Resorting to iRNA, SLC25A3 expression was silenced in human neuroglioma cells, as a first step towards the engineering of a neural model for replicating the results obtained in yeast. This model is essential to understand the mechanisms of tau toxicity at the mitochondrial level and to validate PiC as a relevant drug target. The set of DDD tools here presented will foster the development of innovative and efficacious therapies, urgently needed to cope with tau-related disorders of high human and social-economic impact.

Behavioral and synaptic circuit analysis in models of neuropsychiatric disorders: Dissecting the in vivo role of the postsynaptic density proteins nArgBP2 and Shank3 using genetic engineered mice

Dissertation presented to obtain the Ph.D degree in Biology