Circadian Rhythm Disruptions in Infants

            Circadian rhythm regulates physical, mental, and behavioral changes the body goes through within a 24-hour cycle and  has proven crucial to humans’ overall physical and mental health. The biological clock consists of tens of thousands of neurons that make up the suprachiasmatic nucleus in the hypothalamus which receives direct input from the eyes. Usually developing around 2-4 months of age, it overcomes our homeostatic sleep cycle that often requires infants to take naps throughout the day.

           

            Dr. Jacqueline Yates, at the University of Missouri- Kansas City, examined the link between infants who tended to be exposed to excess light during the night and minimal light during the day and found that it often correlated to health problems later on in life. The researchers even suspected that circadian rhythm disruptions could be linked to sudden unexpected infant death syndrome (SUIDS/SIDS). Majority of SUIDS cases occur in 2–4-month old’s and those at high risk for SUIDS often have abnormal sleep patterns. There are many infants who develop regular sleep patterns and correct their circadian rhythm later in life but have already had changes in their peripheral circadian gene expression which can cause heart, lung, and spleen problems such as high blood pressure, airway inflammation, and poor immune responses. 

            In the article Circadian Disruption and Human Health, Dr. Phyllis Zee outlines the misalignment of endogenous circadian rhythms, the master circadian clock, and environmental circadian system correlation to various diseases/disorders. She highlights their bidirectional relationship by exploring cases of circadian disruptions intensifying symptoms for patients with immunological disorders, obesity, cardiovascular disease, and some psychiatric disorders; as well as diseases such as Alzheimer’s, autism spectrum disorder (ASD) and depression inducing circadian rhythm disruptions. She mainly focused on circadian disruptions caused by work hours in adults and examined how symptoms can manifest over years of an abnormal sleep-wake cycle.

            In conclusion, the implications of circadian rhythm disruptions at any age can cause harm to an individual’s overall mental and physical well-being. If disruptions begin to occur at a young age, they have the possibility of occurring throughout one’s life and impacting many aspects of life. 

 

References:

 

Fishbein, A. B., Knutson, K. L, & Zee, P. C. (2021) Circadian disruption and human health. J Clin 

 

Yates J. The long-term effects of light exposure on establishment of newborn circadian rhythm. J Clin Sleep Med. 2018;14(10):1829–1830.