0021 Bimodality prevalence in a sample of undergraduate students in Sao Paulo city

Abstract

Abstract Introduction The concept of bimodality comprises a fourth circadian phenotype, the bimodal, whose identification is made by a re-scoring of the Morningness-Eveningness Questionnaire and was first described by Martynhak and colleagues in 2010. Bimodal subjects are originally classified as “intermediate” because they answer the questions sometimes as a morning person and, some others, as an evening one. The present work aimed to describe the prevalence of the bimodal chronotype in a sample of undergraduate students in Sao Paulo city. Methods A web-based cross-sectional study conducted between September 2018 and March 2021, with a convenience sampling method, composed by 615 undergraduate students (82% females, mean age: 23.4±6.5 years) from two higher education institutions at Sao Paulo city. Results Forty-four students (7%) had positive bimodality indexes and bimodal individuals comprised 19 students (74% female; 26% male), 3% of the total sample. Conclusion We met our initial goal and found a bimodality prevalence of 3%. The description of bimodality prevalence in a sample of college students is interesting because they may be a maladaptive population from a sleep and rhythmicity point of view, which may be interesting for the design of academic public policies more consistent with the circadian preferences of students. Support (if any) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), Associação Fundo de Incentivo à Pesquisa (AFIP).