Sleep and The Immune System

 

Sleep disturbances have been especially prevalent in the 2019 coronavirus (COVID-19).  Stress and anxiety have been seen in the areas of  employment, health, social isolation, finances, as well as balancing work and family expectations.   As a result, sleep and circadian rhythms are impacted; it is well known that poor sleep correlates with impairments to engage in the occupations of daily life.  Sleep is considered to be a primary Occupation within the scope of an Occupational Therapist’s domain and it has the potential to substantially impact daytime functioning.

 

The results of a recent study by Morin  (2021) document the effects of the COVID-19 pandemic on insomnia and psychological symptoms; the lack of a daily routine, social and leisure activities has disrupted sleep-wake cycles.  As a result, there was a “phase-delay” insomnia meaning that sleep was occurring later at night with later awaking; pair this with more time spent on devices and this further disrupts entry into sleep at night. Healthcare workers have also been affected due to a work schedule that is ever changing.  The concern with “acute insomnia” in response to COVID-19, is that this can often develop into “chronic insomnia”. 

 

Of concern, Lin et al (2020) suggested that insomnia and nightmares experienced during COVID-19 might continue after the pandemic and may indicate an increased risk for long term mental health outcomes such as anxiety and depression.

 

As an Occupational Therapist who specializes in Sleep Disturbances there are a number of sleep hygiene recommendations that can be put in place to help regulate the circadian rhythm (sleep/wake cycle), important for daytime functioning including physical and mental health.

 

Sleep Hygiene can be defined as the practices and habits one can create to promote good sleep on a regular basis.  The following information is taken directly from the Arizona Integrative Medicine Center.

 

1. Be mindful of the basic rhythms of daily life by establishing regular bed and rising time, obtaining exposure to early morning light and evening dim lights, and maintaining regular times for meals and exercise.  You should avoid napping if you have insomnia.                                        
2. Manage caffeine, nicotine, alcohol and other drugs. Caffeinated foods and drinks can affect some people up to 12 hours later.  Even if you do not think caffeine affects you, it may be interfering with the quality of your sleep.                                                                                                    
3. Although regular and adequate cardiovascular exercise promotes healthy sleep, it should be because it raises your core body temperature, which can interfere with sleep.                                                                                                                                                                                                                                                                                                                          
4. Avoid high glycemic and harder to digest foods as bedtime snacks. As an alternative, consider complex carbohydrates (e.g., whole grains, lentils, beans) that may help transport tryptophan, a precursor to melatonin, across the blood-brain barrier.                                                      
5. Create a healthy sleep environment by keeping the bedroom cool (about 68 degrees F), completely dark, quiet, psychologically safe, and green. Use HEPA filtration for clean air and, whenever possible, organic and non-toxic bedding.                                                                         
6. Avoid clock watching at night since it draws you back to waking consciousness. Ideally, position the clock away from the bed or use a non-illuminated battery operated clock to avoid light and subtle EMF radiation.                                                                                                                       
7. Manage hyperarousal and anxiety with cognitive behavioral therapy (CBT) and body-mind techniques.CBT, which is more effective than hypnotics over the long term, addresses sleep-related dysfunctional thoughts and beliefs that trigger arousal.  For some, self-help workbooks may be helpful.  CBT is best coupled with body-mind techniques such as mindfulness meditation, muscular relaxation, heart rate variability, self-hypnosis, breathing exercises, guided imagery, and EEG Neurofeedback which is offered at Neurobehavior Therapy.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
8. Manage bed and bedroom stimulation, which can condition these areas for wakefulness, by using the bed only for sleep and sex. Minimize wakeful time spent there by going to bed only when sleepy and getting out of bed with extended period (15-20 minutes or more) of nighttime wakefulness until becoming sleepy again.                                                                                                                                                                                                                                                                    
9. Consider using a botanical supplement, such as valerian or hops, for sleep for a short term. Melatonin is useful when there is advancing age and/or circadian irregulates.  Be cautious using melatonin with children and young males as this supplement is a hormone and can stimulate testerone in pre-pubescent males.                                                                                                                                                                                                                                                                                                                                                                             
10. Understand that letting go and surrender are key in sleep onset.

 

In addition to the sleep hygiene suggestions listed above from the University of Arizona Center for Integrative Medicine,  daily early light exposure is critical; this can be supplemented with the use of a light box immediately after awakening in the absence of morning light exposure.  It is recommended that light exposure occur for 30 minutes .  Research has also shown that the use of a light box with a blue LED is closer to the sensitivity of the Circadian Rhythm at 500 nm.  This would be preferable although other light boxes offer 10k,000 lux which has also shown to be helpful (Mayo clinic) It is important not to stare into the box and if possible place the box above the visual field. Light therapy is extremely effective because it impacts on circadian rhythm.

 

As was mentioned earlier, the circadian rhythm is a biological rhythm that occurs every 24 hours.  It presents as our Sleep/Wake Cycle as well as fluctuations in core body temperature, melatonin secretion, and Cortisol secretion.  The part of the brain that controls these functions is the suprachiasmatic nucleus located in the hypothalamus of the brain.  This nucleus responds to changes in light and darkness over the course of the day, and especially to high light levels during the morning hours.

 

Light exposure has also been found to improve seasonal affective disorder (SAD); new research has also indicated it improves depressive symptoms and helps advance sleep phase, meaning one will be able to fall asleep earlier.  Initial side effects may include ‘headache, jitteriness, and dizziness” but these were found to be mild and short lived (Sloane, et al 2008). 

It should be noted, if suicidal thoughts, and/or severe agitation or hypomania occur light therapy should be immediately discontinued.