Puberty means girls more at risk of insomnia than boys

According to a new U.S. study of 1014 adolescents who were 13 to 16 years of age, almost 11 percent had suffered from insomnia at some stage.

Insomnia was defined by the researchers when problems falling asleep or staying asleep occurred at least four times a week for one month or longer.

The study found that the teens started having sleep disturbances around the age of 11 and it seems that up until menstruation, girls and boys were equal when it came to insomnia.

However following the onset of their menstrual periods, girls had more than twice the risk of insomnia as boys.

In contrast, maturational development was not associated with insomnia in boys.

The researchers suggest that hormonal changes may play a role in some girls' development of the sleep disorder, and menstruation was related specifically to problems with staying asleep and getting enough deep sleep.

Such forms of insomnia, they say are more likely to have physiological causes, whereas problems with falling asleep in the first place can often be stress-related.

Although poor sleep affects cognitive performance and is associated with poor emotional and physical health, epidemiologic studies among adolescents have been limited and this study is the first such study of insomnia.

Dr. Eric O. Johnson lead study author and researcher with RTI International in Research Triangle Park, North Carolina, says a physiological reason is one of two explanations why menstruation would be related to insomnia; the other being the physical changes that accompany puberty which create "social pressures" that contribute to sleep problems.

The study also found that the girls' higher risk of insomnia was not explained by higher rates of depression, which is often marked by sleep disturbances.

Johnson says they found that of the teens in the study who suffered insomnia, 88 percent continued to have problems sleeping which he says means the problem for many teenagers is longterm.

Johnson and his colleagues concluded that insomnia appears to be common and chronic among adolescents and in view of the consequences of sleep deprivation among teenagers, such as poorer mental acuity, poorer school performance, and even poorer physical and emotional health, prevention and treatment may need to become important priorities.

Current therapies for insomnia include lifestyle changes to encourage sleep such as going to bed and rising at regular times each day, cognitive-behavioral therapy and sleep medications.

The findings are published in the current edition of the journal Pediatrics.