Author: Aashka Patel
For adults, sleep is a mundane activity, and very few sleep-related concerns exist for adults asidefrom the fear of not getting enough of it. For children under the age of one, however, sleep sometimes becomes permanent. Sudden Infant Death Syndrome (SIDS) is defined as the sudden death of an infant without an explainable cause, usually occurring during sleep1. Recently, many studies of this phenomenon have been conducted in the hopes that better preventions might be found.
Currently, there are three major physical risk factors associated with SIDS: brain abnormalities, low birth weight, and respiratory infection2. Infants with improper development of brain regions associated with breathing, heart rate, and arousal have a greater risk of SIDS. Premature birth (thus, low birth weight) leads to immature autonomic processing, which impairs the infant’s regulation of heart rate and breathing pattern. Furthermore, babies who suffer respiratory illnesses also have greater trouble breathing and a greater chance of SIDS. Various environmental factors also appear to contribute to the prevalence of SIDS. For example, babies sleeping on their sides, on soft surfaces, or with their parents have an increased risk of SIDS because of ineffective breathing, most likely due to restricted airways.
Recent research has identified another important environmental factor in SIDS: heat3. Back to Sleep, a popular campaign that encourages parents to make sure infants sleep on their backs instead of their stomachs to prevent the constriction of airways, could also provide benefits concerning the newly-discovered risk factor of heat. Infants lack the thermoregulatory systems that adults have, and instead can regulate their body temperature through the face. Sleeping on the stomach interferes with this regulation, and thus provides another reason why sleeping on their backs is beneficial for infants.
In Canada, a 30-year study was conducted to observe whether increased environmental temperatures resulted in an increase in SIDS4. A total of 196 cases of SIDS were analyzed by comparing the prevalence of SIDS during days of extreme temperatures versus those near average temperature for a given month. The results showed a positive correlation between temperature and SIDS in 3–12 month-old infants specifically. On days when temperatures were greater than 29 °C, there was a 2.78 times greater chance of sudden infant death than on 20 °C days. The connection between SIDS and heat has also been studied using stress gene expression5. Cultured fibroblasts and connective tissue cells were taken in autopsies of SIDS-related deaths, and the expression of four stress responsive genes was measured. High temperatures increased expression of all four genes. The genes HSPAA1Band HSPD1, which become active during elevated stress responses, had the highest levels of expression compared to the control gene.
A decrease in the prevalence of SIDS from 153 to 51.6 deaths per 100,000 live births has occurred since 19806, which may be largely due to the Back to Sleep campaign’s promotion of awareness of SIDS and safer sleeping positions. Of course, no parents should have to worry about their children not waking up. Thankfully, many scientists continue to work towards identifying new causes and preventive measures for SIDS, offering the hope that its incidence will only continue to decrease.
References
- American SIDS Institute, Definition. Retrieved fromhttp://sids.org/what-is-sidssuid/definitions/(2016).
- Mayo Clinic Staff. Causes. Retrieved from http://www.mayoclinic.org/diseases-conditions/sudden-infant-death-syndrome/basics/causes/con-20020269(2016).
- Arnold,C.New risk factor for SIDS? Peaks in cot deaths associated with heat waves. Environ Health Perspect.,123(7), A185(2015).
- Auger, N., Fraser, W. D., Smargiassi, A., & Kosatsky, T. Ambient heat and sudden infant death: a case-crossover study spanning 30 years in Montreal, Canada. Environ Health Perspect.,123(7), 712-716 (2015).
- Rohde, M. C.et al.Heat stress and sudden infant death syndrome -stress gene expression after exposure to moderate heat stress. Forensic Sci Int.,232(1-3), 16-24 (2013).
- AmericanSIDS Institute, Incidence. Retrieved from http://sids.org/what-is-sidssuid/incidence/(2016).
FAQs
Conversely, a well-ventilated bedroom and the use of a fan reduce the risk of SIDS. Thermal stress can lead to infant death by disrupting the respiratory drive, laryngeal closure reflex, and arousal mechanisms. We found greater heat-related SIDS risk among infants 3-11 months old than infants 0-2 months old.
What has been linked to sudden infant death syndrome? ›
While the cause of SIDS is unknown, many clinicians and researchers believe that SIDS is associated with problems in the ability of the baby to arouse from sleep, to detect low levels of oxygen, or a buildup of carbon dioxide in the blood. When babies sleep face down, they may re-breathe exhaled carbon dioxide.
At what age is SIDS no longer a worry? ›
SIDS is less common after 8 months of age, but parents and caregivers should continue to follow safe sleep practices to reduce the risk of SIDS and other sleep-related causes of infant death until baby's first birthday. More than 90% of all SIDS deaths occur before 6 months of age.
Is SIDS higher in hotter countries? ›
There is evidence to suggest that the risk of SIDS increases in overly hot environments, and so this aspect is an integral part of the Safe to Sleep® campaign in the USA and the “Reduce the Risk”/“Back to Sleep” campaigns in other countries (7).
Is SIDS more common in summer? ›
Who Is at Risk for SIDS? Most SIDS deaths happen in babies between 1 and 4 months old, and cases rise during cold weather.
Is SIDS better in the summer or winter? ›
In the United States, more SIDS cases are reported in the fall and winter than in spring or summer. SIDS occurs more often in boys than in girls (approximately a 60- to 40-percent male-to-female ratio).
Can you stop SIDS while it's happening? ›
Even though the thought can be deeply unsettling, experts agree that there aren't any warning signs for SIDS. And since SIDS isn't diagnosed until after an infant has died and the death has been investigated, you can't catch SIDS while it's happening and stop it, for instance, by performing CPR.
What is the single most significant risk factor for SIDS? ›
Sleep position:
Babies placed to sleep on their stomachs or sides are at higher risk for SIDS. Babies who are used to sleeping on their backs but who are placed on their stomachs or sides for sleep, like for a nap, are at very high risk of SIDS.
Does SIDS show up on autopsy? ›
At autopsy, infants who die of SIDS demonstrate multiple external and internal findings insufficient to explain the cause of death. [28] External findings may include frothy, blood-tinged fluid at the nares in an otherwise well-developed infant.
Can you resuscitate a SIDS baby? ›
If possible, the family needs to understand that SIDS deaths occur and there's no way to either predict these deaths or prevent them. Further, they need to understand that the baby is beyond medical care and attempting resuscitation measures won't bring back their child.
What are the symptoms? SIDS has no symptoms or warning signs. Babies who die of SIDS seem healthy before being put to bed. They show no signs of struggle and are often found in the same position as when they were placed in the bed.
How to stop worrying about SIDS? ›
How can I stop this? You can't but don't worry. Once a baby can roll over by themselves, the brain is mature enough to alert them to breathing dangers, and by the time the child is 6 months old, the improved motor skills will help to rescue the baby, so the SIDS risk is greatly reduced.
Can heat cause SIDS? ›
Overheating. Being too warm while sleeping can increase a baby's risk of SIDS .
Why is SIDS so low in Japan? ›
The rate of infant deaths due to SIDS fell by half between 1984 and 2004, decreasing from 0.42 deaths per 1,000 live births to 0.24 per 1000, according to a study , opens new tab that credited the decline to public health campaigns starting after 1996 that discouraged putting infants to sleep face-down, and other known ...
What state has highest SIDS rate? ›
While District of Columbia reported the highest infant mortality rates, the states with the highest rates include: Mississippi (11.46), Louisiana (9.85), Alabama (9.53), South Carolina (9.49), North Carolina (8.81), Tennessee (8.77), Ohio (8.17), West Virginia (8.16), and Georgia (8.07).
What is the best temperature to avoid SIDS? ›
It is important to make sure that your baby is a comfortable temperature – not too hot or too cold. The chance of SIDS is higher in babies who get too hot. A room temperature of 16-20°C – with light bedding or a lightweight, well-fitting baby sleep bag– is comfortable and safe for sleeping babies.
What temperature is too hot for a baby to sleep? ›
Q: Is 78 degrees too hot for baby to sleep? A: Yes, 78 degrees Fahrenheit (25.6 degrees Celsius) is considered too hot for a baby to sleep comfortably. It is recommended to keep the room temperature between 68-72 degrees Fahrenheit (20-22 degrees Celsius) for a safe and comfortable sleeping environment for infants.
Why is SIDS higher at 2 months? ›
Why Does SIDS Peak at 2-4 Months? The widely accepted explanation for the SIDS peak has to do with the timeline of brain development. “Up to 4 months old, the part of the brain that controls breathing and wakefulness is under a lot of development,” Juliet explains.
Does cold air prevent SIDS? ›
A fan helps regulate the room's temperature, especially during warmer months. It circulates cool air, preventing the baby from overheating and ensuring a comfortable sleep environment. Maintaining an optimal room temperature is crucial for reducing the risk of SIDS.
