Money worries are increasingly keeping teenagers awake at night with fears about the environment and war declining, a 28 year study has shown.
In the 1980s, when youngsters were asked what issues produced sleepless nights, climate change and the threat of global conflict caused high levels of anxiety.
But recent recessions have made their concerns more prosaic, with teenagers increasingly nervous of financial insecurity rather than the end of the world.
Youngsters are now nearly 92 per cent more likely to suffer sleep disturbances while worrying about money, personal accidents, bullying or terrorist attacks, compared with nuclear attacks or the environment.
Lead author Dr Nanette Danielsson, of Karlstad University in Sweden, said: “Many adolescents have sleep disturbances, and this is associated with adverse consequences.
“Sleep disturbance was strongly associated with worry for the family’s financial situation, followed by worry about illness or accidents.
“Relationships between sleep disturbance and worry for environmental destruction and nuclear war were weaker.
“Concerns closely tied to one’s personal life, as well as current political threats, may have stronger associations with sleep disturbance than global threats due to a closer proximity to one’s own life situation.”
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The Swedish researchers have been quizzing youngsters annually for the last two decades.
Between 1988 and 2011, more than 20,000 Swedish teenagers were asked to complete a questionnaire about living conditions and their health. Sleep disturbance was reported by 24 per cent of girls and 16 per cent of boys.
They were asked if they were worried about: family economy, parent becoming unemployed, own accident, own serious illness, family member in an accident, family member becoming seriously ill, being bullied or beaten up, nuclear war, environmental destruction, and terrorist attacks.
Youngsters were 81 per cent more likely to be worried about financial security than in 1988, but half as likely to be concerned about nuclear war than they were in the early 90s. Sleep disruption due to fears about an environmental destruction also fell by 60 per cent between 2011 and the 1990s.
Researchers say knowing what worries teenagers enough to stop them sleeping is important as sleep problems in adolescence can lead to mental health problems in adulthood.
The study was published in the journal Sleep Health.