Trends in self-reported sleep problems, tiredness and related school performance among Finnish adolescents from 1984 to 2011

The aim of this study was to investigate long-term trends in insomnia symptoms, tiredness and school performance among Finnish adolescents. A time-series from 1984 to 2011 was analysed from two large-scale survey studies, the Finnish School Health Promotion Study and the Health Behavior in School-Aged Children study. A total of 1,136,583 adolescents aged 11-18 years answered a standardized questionnaire assessing frequency of insomnia symptoms, tiredness and school performance. A clear approximately twofold increasing trend in insomnia symptoms and tiredness was found from the mid-1990s to the end of the 2000s. The increase was evident in all participating age groups and in both genders. Af…