Sleep Apnea and Growth Problems
When sleep is disrupted in young children, especially those who have yet to finish growing, there can be significant consequences. Growth hormone is secreted during the night during specific sleep stages. Deep, non-REM sleep that occurs early in the night seems especially important for its secretion. This sleep predominates in the first third of the night. If this sleep is disrupted, growth may not occur normally. Children who are affected may begin to fall off their growth curve: for example, if a child was in the 50th percentile by height and weight in early development, the affected child may fall into the 10th percentile over time.
As an example of the impacts of sleep disorders on normal growth, it is known that sleep apnea in children can have profound effects on growth. These children have periodic obstructions in their upper airway that can cause snoring or pauses in their breathing. The body awakens itself into lighter sleep to open the airway and resume normal breathing. As such, deeper sleep may become fragmented and growth hormone secretion may be compromised.
Any sleep disorder that disrupts deep sleep may decrease growth hormone secretion. Moreover, simply not getting enough sleep could have the same effects. Fortunately, children whose sleep apnea is treated undergo a rebound growth spurt. Many will recover to their prior growth trajectory, moving back to their prior percentiles. This suggests that addressing the other conditions that undermine sleep quality, such as restless legs syndrome, may likewise be beneficial.
Sleep Deprivation, Failure to Meet Sleep Needs, and Excessive Weight
The risk of sleep deprivation causing obesity has been well studied in adults. Although the mechanism is not fully understood, it may relate to hormonal changes or effects on normal metabolism. A similar association appears to exist in children. When children don’t get enough sleep at night to meet their age-based sleep needs, they are at risk of undermining their overall health.
Over the past 20 years, many independent studies of more than 50,000 children support the fact that sleep deprivation appears to be associated with an increased risk of obesity. In 2002, a study of 8,274 Japanese children who were 6-7 years old showed that fewer hours of sleep increased the risk of childhood obesity.
These consequences appear to persist beyond the period of sleep disruption. In 2005, a study showed that sleep deprivation at age 30 months predicted obesity at age 7 years. The researchers hypothesize that sleep disruption may cause permanent damage to the area of the brain called the hypothalamus, which is responsible for regulating appetite and energy expenditure.
The risks of untreated sleep disorders should prompt careful attention by parents to any signs that their child is not getting enough quality sleep. If you suspect a problem, you should speak with a pediatrician. A careful evaluation may offer some reassurance, and when treatment is indicated, it may help your child to grow and thrive.