Padrões de sono de acordo com etnia e características sócio-demográficas na população de São Paulo
Arquivos
Data
2022
Autores
Kondo, Júlia [UNIFESP]
Orientadores
Poyares, Dalva Lucia Rollemberg [UNIFESP]
Tipo
Trabalho de conclusão de curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Resumo
O sono é um comportamento expresso de forma diferente para cada indivíduo, no entanto, algumas populações expressam padrões de sono em comum, o que pode ser observado em diversas etnias. Estudos anteriores já provaram a existência de disparidades do sono em populações de etnias distintas, especialmente na comparação entre caucasianos e afro-americanos. Entretanto, a maioria destes estudos considera a etnia autorrelatada e avalia o sono de forma subjetiva. Este fato faz com que importantes influenciadores do sono, como características sócio-demográficas, sejam pouco considerados. Além disso, fatores culturais também podem afetar a forma de como cada indivíduo lida com distúrbios do sono, o que interfere significativamente na avaliação de questionários. Assim, o objetivo deste estudo foi elucidar as disparidades do sono em diferentes etnias a partir de uma análise da ancestralidade genética e de ferramentas objetivas de avaliação do sono, buscando também compreender os efeitos moduladores do sono de características sócio-demográficas, além de possibilitar o estudo de risco a morbidade relacionada ao sono para cada etnia. A população em estudo faz parte do projeto de pesquisa EPISONO, que engloba a população da cidade de São Paulo, a qual é conhecida por sua diversidade étnico-racial. Os voluntários responderam a questionários, incluindo sobre etnia autorrelatada, realizaram exame de polissonografia e foram submetidos a coleta de sangue para extração de DNA. Após a genotipagem e a definição das amostras com DNA de alta qualidade disponível para análises genéticas, foi realizada a seleção de 31 Marcadores Informativos de Ancestralidade (AIMs), que apresentaram alto nível de diferença de frequência alélica entre as três populações fundadoras de brasileiros (europeus, africanos ocidentais e nativo-americanos) e estimada sua contribuição genética para cada participante. A partir disso, foi realizada uma análise de clusters via método da análise de classes latentes, definindo 3 clusters que melhor classificaram a amostra de acordo com o grupo étnico: africano (n=255), caucasiano (n=668) e nativo-americano (n=83). A comparação entre os clusters e a etnia autorrelatada apresentou uma clara discrepância entre as duas análises: no cluster do grupo étnico africano, 159 indivíduos (62,60%) se declararam negros ou mulatos; já no grupo caucasiano, 496 (76,10%) se identificaram como caucasiano; por fim, no grupo nativo-americano, apenas 8 (10,30%) responderam o questionário como nativo-americano. Aplicando o modelo ajustado para as variáveis de confusão (idade, classe social e sexo) na etnia genética classificada por clusters, pode-se observar uma diferença estatisticamente significante entre as etnias e variáveis do sono. Os africanos apresentaram maior latência de sono (p<0,001) em relação aos outros dois grupos. Além disso, os caucasianos apresentaram maior tempo total de sono (p=0,014) e melhor eficiência do sono (p=0,021) em relação aos africanos. Em relação ao índice de despertares respiratórios (p=0,024) e PLMI (p=0,001), observa-se maiores índices dos caucasianos em comparação aos africanos em ambas variáveis. Podemos concluir que a ancestralidade genética possui um efeito modulador do sono e afeta diretamente no padrão e na qualidade do sono, especialmente quando comparadas as etnias africana e caucasiana, e deve-se considerar como um fator importante na prática clínica.
Sleep is a behavior expressed differently for each individual, however, some populations express common sleep patterns, which can be observed in different ethnic groups. Previous studies have already proven the existence of sleep disparities in populations of different ethnicities, especially when comparing Caucasians and African Americans. Nevertheless, most of these studies consider self-reported ethnicity and assess sleep subjectively. This fact represents that important influencers of sleep, such as socio-demographic characteristics, are poorly considered. In addition, cultural factors can also affect the way each individual deals with sleep disorders, which significantly interferes with the assessment of questionnaires. Therefore, the aim of this study was to elucidate sleep disparities in different ethnic groups based on an analysis of genetic ancestry and objective sleep evaluation tools, also assessing the sleep modulating effects of socio-demographic characteristics, in addition to enabling the risk study sleep-related morbidity for each ethnicity. The population under study is part of the EPISONO research project, which encompasses the population of the city of São Paulo, which is known for its ethnic-racial diversity. Volunteers answered questionnaires, including self-reported ethnicity, underwent full-night polysomnography and blood collection for DNA extraction. After genotyping and defining the samples with high-quality DNA available for genetic analysis, 31 ancestry-informative markers (AIMs) were selected, which showed a high level of allelic frequency difference between the 3 founding populations of Brazilians (Europeans, West-Africans, and Native Americans) and it was estimated their genetic contribution for each participant. Based on that, a cluster analysis was performed via latent class analysis method defining 3 clusters that best classified the sample according to ethnic group: African (n=255), Caucasian (n=668) and Native American (n=83). The comparison between clusters and self-declared ethnicity showed a clear discrepancy between these analyses: in the African ethnic group cluster, 159 individuals (62.60%) declared themselves as Black or Mulatto; in the Caucasian group, 496 (76.10%) self-identified as Caucasian; and in the Native American group, only 8 (10.30%) answered the questionnaire as Native American. Applying the adjusted model for the confounding variables (age, social class and sex) in the genetic ethnicity classified by clusters, a statistically significant difference between ethnicities and sleep variables can be observed. Africans had higher sleep latency (p<0.001) compared to the other groups. Moreover, Caucasians had longer total sleep time (p=0.014) and better sleep efficiency (p=0.021) compared to Africans. Regarding the respiratory arousals index (p=0.024) and periodic leg movements index (p=0.001), a higher rate of Caucasians compared to Africans was observed in both variables. We conclude that genetic ancestry has a modulating effect on sleep and it directly affects the pattern and quality of sleep, especially when comparing Africans and Caucasians, it should be considered as an important factor in clinical practice.
Sleep is a behavior expressed differently for each individual, however, some populations express common sleep patterns, which can be observed in different ethnic groups. Previous studies have already proven the existence of sleep disparities in populations of different ethnicities, especially when comparing Caucasians and African Americans. Nevertheless, most of these studies consider self-reported ethnicity and assess sleep subjectively. This fact represents that important influencers of sleep, such as socio-demographic characteristics, are poorly considered. In addition, cultural factors can also affect the way each individual deals with sleep disorders, which significantly interferes with the assessment of questionnaires. Therefore, the aim of this study was to elucidate sleep disparities in different ethnic groups based on an analysis of genetic ancestry and objective sleep evaluation tools, also assessing the sleep modulating effects of socio-demographic characteristics, in addition to enabling the risk study sleep-related morbidity for each ethnicity. The population under study is part of the EPISONO research project, which encompasses the population of the city of São Paulo, which is known for its ethnic-racial diversity. Volunteers answered questionnaires, including self-reported ethnicity, underwent full-night polysomnography and blood collection for DNA extraction. After genotyping and defining the samples with high-quality DNA available for genetic analysis, 31 ancestry-informative markers (AIMs) were selected, which showed a high level of allelic frequency difference between the 3 founding populations of Brazilians (Europeans, West-Africans, and Native Americans) and it was estimated their genetic contribution for each participant. Based on that, a cluster analysis was performed via latent class analysis method defining 3 clusters that best classified the sample according to ethnic group: African (n=255), Caucasian (n=668) and Native American (n=83). The comparison between clusters and self-declared ethnicity showed a clear discrepancy between these analyses: in the African ethnic group cluster, 159 individuals (62.60%) declared themselves as Black or Mulatto; in the Caucasian group, 496 (76.10%) self-identified as Caucasian; and in the Native American group, only 8 (10.30%) answered the questionnaire as Native American. Applying the adjusted model for the confounding variables (age, social class and sex) in the genetic ethnicity classified by clusters, a statistically significant difference between ethnicities and sleep variables can be observed. Africans had higher sleep latency (p<0.001) compared to the other groups. Moreover, Caucasians had longer total sleep time (p=0.014) and better sleep efficiency (p=0.021) compared to Africans. Regarding the respiratory arousals index (p=0.024) and periodic leg movements index (p=0.001), a higher rate of Caucasians compared to Africans was observed in both variables. We conclude that genetic ancestry has a modulating effect on sleep and it directly affects the pattern and quality of sleep, especially when comparing Africans and Caucasians, it should be considered as an important factor in clinical practice.