A new study titled “The Heritability of Insomnia Progression during Childhood/Adolescence: Results from a Longitudinal Twin Study” of twins suggests that insomnia in childhood and adolescence is partially explained by genetic factors. Results show that clinically significant insomnia was moderately heritable at all stages of the longitudinal study.
Genetic factors contributed to 33 to 38 percent of the insomnia ratings at the first two stages of the study, when participants had an average age of 8 to 10 years. The heritability of insomnia was 14 to 24 percent at the third and fourth follow-up points, when the average age of participants was 14 to 15 years. The remaining source of variance in the insomnia ratings was the non-shared environment, with no influence of shared, family-wide factors. Further analysis found that genetic influences around age 8 contributed to insomnia at all subsequent stages of development, and that new genetic influences came into play around the age of 10 years.
“Insomnia in youth is moderately related to genetic factors, but the specific genetic factors may change with age,” said study author Philip Gehrman, PhD, assistant professor in the Department of Psychology at the University of Pennsylvania in Philadelphia. “We were most surprised by the fact that the genetic factors were not stable over time, so the influence of genes depends on the developmental stage of the child.”
Study results are published in the January issue of the journal Sleep.
