Kids’ genes, environment affect sleep differently

PAR_sleeping_0219

A new study based on pairs of Canadian twins suggests that genetics play a strong role in how long kids sleep at night, but their environment may be more important for afternoon naps.

Researchers compared sleep patterns for close to 500 sets of identical or fraternal twins. They found that especially as kids got older, environmental influences — which include when parents put kids in bed, for example — explained more and more of their napping differences.

“Even though the results do not explicitly state which are the environmental factors,” says Sonia Brescianini, “researchers in the field think that familial habits at bed time, sleeping routines and in general sleep hygiene measures are for sure a means of improving sleep in children.”

Brescianini, a researcher with the Italian Twin Register at Rome’s Istituto Superiore di Sanità, who was not involved in the new study, told Reuters Health in an email that past research has also suggested a child’s environment may be more important than genetics for daytime sleep habits.

The new study involved 983 individual children born in greater Montreal, Canada, from 1995 to 1998. Mothers were asked about each twin’s daytime and nighttime sleep patterns at age 6, 18, 30 and 48 months.

By comparing sets of identical and fraternal twins, Dr. Jacques Montplaisir from the University of Montreal and his colleagues were able to determine how much of kids’ sleep variation was due to genes — which are the same in identical twins — and how much to environmental factors.

For example, Brescianini explains, the more identical twins are similar and fraternal twins are not for a given trait such as sleep schedules, the more that trait is likely to be genetic. But if both types of twins resemble each other in similar ways, the trait is likely affected by a child’s environment.

At three of the four time points, genetics accounted for between 47 and 58 percent of nighttime sleep duration. The majority of children slept 10 or 11 continuous hours at night.

The one age when environment seemed to play a strong role in overnight sleep was at 18 months. That suggests that age “might be an appropriate time of intervention in children with not satisfying sleep duration and quality,” Brescianini says.

But genes never explained more than about one-third of daytime nap length, the researchers reported Monday in Pediatrics.

Family routines and other shared environmental influences, on the other hand, accounted for between 33 and 79 percent of whether or not twins were napping during the day, and for how long. That association became stronger as children got older and average nap length shortened.

The researchers said a similar study needs to be done using more exact tools to measure sleep, such as movement sensors or laboratory monitors.

In addition, it will be helpful to look at what family-related factors may affect daytime sleep, Montplaisir and his colleagues wrote.

“Good sleep duration and quality is very important for children’s physical and mental health because sleeping behavior has been associated with obesity, poor school performance and other behavioral disorders,” Brescianini says.

“In order to promptly intervene, more knowledge is needed on how sleeping behavior changes through childhood.”


News
Entertainment
Sports
Lifestyle
Local

TIPS: How to take great photos during 'Manhattanhenge'

Grab your camera and make the perfect picture this Saturday.

National

Seinfeld emoji cound be available next week

Get your puffy shirts and your marble rye ready, America. Seinfeld emoji could become available as early as next week.

Local

MAP: New York City street closures July 11,…

A block party in Times Square, Bastille Day celebrations and a festival will cause traffic delays and street closures in New York City this weekend.

Local

Thousands come to pay respects to fallen NYC…

Thousands turned out to say farewell to fallen firefighter Gordon Ambelas at St. Clare’s Church in Staten Island this morning.

Movies

Interview: Matt Reeves on directing 'Dawn of the…

"Dawn of the Planet of the Apes" director Matt Reeves discusses his love for the franchise, working with actors as apes and the weight of 3-D cameras.

Television

Final season of 'Glee' will be only 13…

The final season of "Glee" will officially be only 13 episodes, instead of the usual 22.

Entertainment

Complex characters, juicy scripts boost Netflix's Emmy nominations

The unconventional approach to TV at Netflix netted 31 Emmy nominations, a major achievement after plunging into original programing just last year.

Entertainment

Actor Josh Duhamel dons bunny suit to encourage…

The former Transformers star and husband to singer Fergie took to the Venice Beach boardwalk in California in a bright pink, Christmas-story inspired bunny suit Wednesday to help spread the…

NFL

Which Jets player has the best odds at…

Metro New York asked Bovada.LV to rank the top three contenders for the NFL MVP on the Jets.

World Cup

Argentina prevails in penalties, advances to final

The drama never seems to subside as the World Cup finally has its final two.

MLB

A Joffrey Ballet dancer threw the most beautiful…

http://youtu.be/Hg61JOZJrYM?t=29s While asked to throw a first pitch at a baseball game can be a treacherous and/or embarrassing experience (see Cent, 50), sometimes everything can…

World Cup

World Cup semifinals preview: Holland vs. Argentina

The second semifinal pits another South American soccer power against a European one.

Wellbeing

This Week in Health: Sexual headaches can be…

Sexual headaches: an under-discussed health issue Location: U.S. Results: If getting frisky brings on a headache, you’re not alone. Headaches associated with sexual activity represent a…

Food

Head to FiDi for free Chia Pods from…

They may have been last summer's darlings, but chia seeds have definitely not gone out of style. A great source of omega-3 fatty acids, they…

Wellbeing

Stop thinking your diabetes risk begins above a…

When it comes to diabetes research, a new study says black and Asian adults may be at risk for developing diabetes at a lower weight…

Food

Christian Siriano inspires Magnum's color-blocked dessert

Christian Siriano, chef Andrew Carmellini and Magnum team up to create "America's Most Fashionable Chocolate Dessert."