Second international School On Mind, Brain And Education

2007, May 22-26

Basic and Applied Topics
in Biological Rhythms and Learning

Directors: Antonio M. Battro and Kurt W. Fischer
Program officer: María Lourdes Majdalani


Abstract: Frida Marina Fischer
Faculdade de Saúde Pública da Universidade de Sao Paulo. BRASIL

The double burden of studying and working: effects on sleep, sleepiness and health among Brazilian working teens
Studies to evaluate the effects of the double journey- study and work on teens were carried out by Fischer et al (2001, 2003a, b) and Teixeira et al (2004, 2006, 2007). We were particularly interested to analyze health symptoms, the sleep-wake cycle and sleepiness patterns.
Along 1998-1999, fundamental and high school students, attending morning and evening classes, from 14-18 years old, living in two towns located at the countryside of the State of Sao Paulo were interviewed and answered a comprehensive questionnaire on sociodemographic, working and living conditions, health symptoms, including sleep duration during working days and days-off. This study showed the working teens referred shorter sleep duration when compared to their colleagues who did not work. During the weekend, those who work referred longer sleeping times suggesting a sleep debt along the working days.
Two other studies were carried out among high school students in the city of Sao Paulo attending morning and evening classes, from 14-18 years old (2001) and evening classes, from 14-21 years old (2003). Sleep duration and sleepiness were evaluated using subjective (questionnaires, diaries) and objective measures (actigraph) during working days and days-off. Working teens showed earlier awakenings, shorter sleep duration, more difficulties to awake up and a worse sleep quality than non-working teens during the working days. Conversely, during days-off, particularly on Sundays, working teens went to bed earlier and had an easier awakening than non-workers. Sex was a significant factor associated to sleep duration, and males showed a shorter sleep than females. The female students showed higher diurnal sleepiness, and more sleep disturbances. The weekly working time affected the sleep duration: those working 40 hours and more had shorter sleep than non-workers. The data suggested that non-worker/unemployed female students had a larger consumption of alcoholic drinks than males and non-workers. The sleepiness patterns of working teens were significantly different than non-workers, as they were more sleepy early morning and late evening. Working teens face more difficulties to arrive at school on time, and to remain in school during the school hours. Governmental policies encouraging teens into the labor market should take into account the negative factors associated to the double journey of work and study.