Why Does Sleep Efficiency Matter?

Sleep efficiency refers to the percentage of time a person sleeps to the amount of time a person spends in bed. It is calculated by the ratio of the total time spent asleep (TST) in a night compared to the total amount of time spent in bed. An efficient sleep leads to a deeper sleep of better quality with lesser disturbances that may result in good stamina and sufficient rest upon waking, while an inefficient sleep may lead to uneasiness and fatigue.

Sleep Efficiency Rates

Sleep efficiency rates tend to vary from person to person. Normal sleep efficiency is considered to be 80% or greater. For example, if an individual spends 8 hours in bed, at least 6.3 hours or more should be spent sleeping to achieve 80% or greater sleep efficiency. Most healthy and young adults have sleep efficiencies above 90%.

How Does Genetics Influence Sleep Efficiency?

UFL1 Gene and Sleep Efficiency

UFL1 is one of the genes in the ubiquitin pathway - the principal mechanism behind protein breakdown.
This pathway has also been implicated in schizophrenia, a condition in which poor sleep efficiency is a common symptom.
The relevance of this pathway in sleep disturbances was further explored in another study.
The study indicated that the expression of a protein UFM1, a part of UFL1, increased after partial sleep restriction.

rs75842709 and Sleep Efficiency

A GWAS analysis found a significant correlation between a variant (rs75842709) near the UFL1 gene and sleep efficiency.
The T-allele was associated with a 5.7% decreased sleep efficiency.

Non-genetic Influences Of Sleep Efficiency

Some factors that lower sleep efficiency:
- Pain
- Higher fatigue
- Less activity during the day
- Light at night
- Jet lag
- Sleep environment

Tips To Improve Sleep Efficiency

1. Get some exercise during the day and get active.
2. Try to do a calm and relaxing activity, like taking a shower or reading a book before you sleep.
3. Avoid watching television or using your mobiles at least an hour before bedtime.
4. Eliminate distractions before sleeping. Avoid using flashy, blinking lights, having the television on, and using your cell phone.
5. Try to associate your bed with falling asleep and avoid doing other activities like reading or watching television on the bed before you fall asleep. Read at your table or any other convenient spot, and then fall asleep on your bed.
6. If you’re awake in the middle of your sleep time for more than 15-20 mins, try to move around and do some relaxing activity to fall asleep again.
7. Try to restrict your bedtime if most of it is spent laying awake. This can help meet your sleep needs but should be followed under the guidance of a doctor.

Summary

1. Sleep efficiency refers to the percentage of time a person sleeps to the amount of time a person spends in bed. Efficiency rates tend to vary from person to person.
2. The UFL1 gene involved in protein breakdown is implicated in schizophrenia, a condition in which poor sleep efficiency is a common symptom. The T allele of rs75842709 SNP is associated with a 5.7% decrease in sleep efficiency.
3. Pain, sleep environment, jet lag, higher fatigue, less activity during the day are some of the non-genetic influences on sleep efficiency.
4. Being active, doing calm and relaxing activities before sleeping, avoiding television and mobile usage before sleeping, and restricting bedtime to establish a proper sleep schedule can improve sleep efficiency.

Reference

https://pubmed.ncbi.nlm.nih.gov/27126917/

Sleep Latency: How Long Does It Take You to Fall Asleep?

Sleep latency (also known as sleep onset latency) refers to the amount of time it takes for a person to fall asleep. Usually, normal sleep latency is 5-15 minutes. If sleep latency is less than five minutes, it may suggest some level of excessive sleepiness, and if it is greater than 15 minutes, it may be due to sleep initiation issues.
Sleep latency varies from person to person. An ideal sleep latency period lays the foundation for a solid night's sleep. Sleep latency directly affects sleep efficiency, because if a person is able to fall asleep quickly, they are more likely to have an efficient sleep.

How Does Genetics Influence Sleep Latency?

Research studies have demonstrated the association between certain variants in RBFOX3 and DRD2 genes and sleep latency. The RBFOX3 gene plays a key role in neuron-specific alternative splicing (a process that removes the "unwanted" portions from the DNA and connects useful portions to form a functional gene).

RBFOX3 Gene and Sleep Latency

RBFOX3 also influences the release cycle of neurotransmitters, including GABA (gamma-aminobutyric acid) and various monoamines, vital to the human circadian clock.

DRD2 Gene and Sleep Latency

The DRD2 gene encodes a dopamine receptor. Dopamine is a 'happy hormone' that is crucial for signaling pleasure and reward. Dopamine and its receptors also play a part in controlling the sleep-wake cycle. Mainly, dopamine can help keep you awake and alert. The DRD2 gene variations may affect this wake/sleep switch, leading to a tendency for shorter sleep duration and sleep onset latency.

rs17601612 And Sleep Latency

The rs17601612 is a G>C polymorphism located in the DRD2 gene, which might affect the wake/sleep cycle. A study, Cade, Brian E., et al.2016, has shown that the rs17601612 C allele was strongly associated with shorter sleep latency than the G allele.

Non-genetic Influences on Sleep Latency

A variety of other factors influence sleep latency. They include:
- Age
- Gender
- Dietary intake
- Sedentary life
- Consumption of stimulants
- Illness such as depression

Effects of Delayed Sleep Latency on Health?

Prolonged sleep latency may shorten sleep duration and lead to a variety of problems, including depression, loss of productivity, irritability, cognitive impairment, poor academic performance in children, and adolescents. Persistently increased sleep latency is also a key indicator of delayed sleep phase syndrome, insomnia, sleep deprivation, and narcolepsy.

Tips To Improve Sleep Efficiency

1. Get some exercise during the day and be active.
2. Try to do a calm and relaxing activity, like taking a shower or reading a book before you sleep.
3. Avoid watching television or using your mobile at least an hour before bedtime.
4. Try to associate your bed with falling asleep and avoid doing other activities like reading or watching television on the bed before you fall asleep. Read at your table or any other convenient spot, and then fall asleep on your bed.
5. If you’re awake in the middle of your sleep time for more than 15-20 mins, try to move around and do some relaxing activity to fall asleep again.
6. Try to restrict your bedtime if most of it is spent laying awake. This can help meet your sleep needs but should be followed under the guidance of a doctor.

Summary

1. Sleep latency is the amount of time it takes for a person to fall asleep. It is usually in the range of 5-15 minutes. It varies from person to person.
2. Certain variants of RBFOX3 and DRD2 genes have an association with sleep latency. The DRD2 gene is a dopamine ('happy hormone') receptor. The C allele of an SNP rs17601612 located on this gene is associated with shorter sleep latency compared to the G allele.
3. Poor sleep latency shortens sleep duration and can lead to a variety of health issues.
4. Being active, doing calm and relaxing activities before sleeping, avoiding television and mobile usage before sleeping, and restricting bedtime to establish a proper sleep schedule can improve sleep efficiency.

References

https://pubmed.ncbi.nlm.nih.gov/27142678/
https://pubmed.ncbi.nlm.nih.gov/26464489/

What is Restless Leg Syndrome?

Restless Leg Syndrome (also known as Willis-Ekbom Disease) is a neurologic and sleep-related movement disorder characterized by an irresistible urge to move in the legs, which typically occurs or worsens at rest. Affected people may experience abnormal, uncomfortable sensations ( paresthesia or dysesthesias ) that are often linked to cramping, crawling, burning, aching, itching, or prickling deep within the affected areas.

This condition has a 10% prevalence rate, with an increase in incidences as age advances. Since the symptoms occur during sleep and relaxation, it could disrupt a good night's sleep.
Restless leg syndrome causes an uncomfortable urge to move, which can be relieved by walking or moving the extremities. This interferes with sleep maintenance

How Does Genetics Influence the Risk of Restless Leg Syndrome (RLS)?

Restless leg syndrome shows an anticipation inheritance - with each generation, the age of onset of this condition advances.

A GWAS meta-analysis study of restless leg syndrome (RLS) in European ancestry has demonstrated the significant association of RLS with MEIS1, BTBD9, PTPRD, and other genes.

BTBD9 and RLS

BTBD9 gene variants have been associated with RLS, with two experimental models providing better insights. The loss of this gene was associated with increased waking from sleep, motor activity, higher motor restlessness, and altered serum iron levels.

MEIS1 and RLS

The MEIS1 gene is a transcription factor that plays a key role in hematopoiesis, endothelial cell development, and vascular patterning.
It also plays a role in neurodevelopment.
Research studies have shown that the reduced MEIS1 levels and function of the gene may contribute to the pathogenesis of sleep-related disorders.

rs113851554 And RLS
The rs113851554 is a G>T polymorphism located in the MEIS1 gene, which is found to be correlated with multiple sleep disorders.

A GWAS meta-analysis study of RLS in European ancestry has demonstrated that the rs113851554 T allele is associated with an increased risk of developing RLS susceptibility.

Non-genetic Influences on RLS Risk

Some nutritional deficiencies have been implicated in RLS. They include:
- Vitamin D deficiency
- Iron deficiency

Some medical conditions associated with RLS are:
- Depression
- Diabetes
- Fibromyalgia
- Rheumatoid arthritis
- Hypothyroidism

Effects of Restless Legs Syndrome on Health

1. Many people with restless leg syndrome find it hard to fall asleep and have a good quality of sleep at night.
2. There is a risk of depression and other health problems.
3. Napping during the day becomes difficult.
4. It interferes with your day-to-day activities, concentration, and productivity.
5. It causes daytime sleepiness and fatigue.
6. About 80% of people with RLS have a condition called periodic limb movement of sleep which causes the legs to twitch or jerk during sleep. This leads to sleep deprivation.

Tips for Managing Restless Leg Syndrome (RLS)

Iron Supplements : Iron deficiency is one of the leading causes of RLS. If you test positive for iron deficiency, you may get started on iron supplements after consulting a qualified healthcare professional.
Baths and massages : Warm showers and massages can help relax muscles and prevent unnecessary leg movements.
Exercise : Restless Legs Syndrome foundation recommends moderate exercising to help manage RLS.
Avoid caffeine : High caffeine intake can worsen RLS. Either limit or avoid caffeine intake.

Summary

1. Restless Leg Syndrome is a neurologic and sleep-related movement disorder characterized by an irresistible urge to move in the legs, which typically occurs or worsens at rest. Symptoms occur during sleep, and relaxation disrupts a good night's sleep.
2. A significant association between MEIS1, BTBD9, PTPRD genes, and RLS has been established. The T allele of the rs113851554 SNP found in the MEIS1 gene is associated with an increased risk of developing RLS.
3. Vitamin D deficiency, iron deficiency, depression, and diabetes are associated with RLS.
   RLS leads to a risk of depression, other health problems, problems with napping, and sleep deprivation. It interferes with your day-to-day activities, concentration, and productivity.
4. Iron supplements, baths and massage, exercise, and caffeine can help manage restless leg syndrome.

Reference

https://pubmed.ncbi.nlm.nih.gov/29029846/

Introduction: What is Sleep Bruxism?

Sleep Bruxism (also known as Teeth Grinding) is defined as repetitive jaw muscle activity during sleep. It is characterized by an unconscious act of grinding or clenching one's teeth tightly together. Over time, it could lead to damage of teeth, oral health conditions, facial muscle pain, sleep disturbances, difficulty while speaking or eating.

Sleep Bruxism is more common in children, adolescents, and young adults than middle-aged and older adults.

The prevalence of sleep bruxism is estimated to be around 15% in adolescents, around 8% of middle-aged adults, and only 3% in older adults.

According to statistical studies 6-50% of children experience nighttime teeth grinding.

How Does Genetics Influence Sleep Bruxism Risk?

Multiple studies have demonstrated that there may be a degree of inherited susceptibility to develop sleep bruxism. According to a study, around 21-50% of affected individuals have an immediate family member who had sleep bruxism during childhood.

Few studies have shown the significant associations of certain variants in neurotransmitters like dopamine, serotonin, and others ( DRD3, HTR2A, COMT, MMP9, and others) with sleep bruxism.

DRD3 Gene and Sleep Bruxism

The DRD3 gene encodes the D3 subtype of the dopamine receptor, which is localized to the regions of the brain involved in cognitive, emotional, and endocrine functions.
Variations in DRD3 are implicated in the physiopathology of diseases affecting those functions.

rs6280 and and Sleep Bruxism

The rs6280 is a T>C polymorphism located in the DRD3 gene, where the C allele may increase dopamine affinity and efficacy. Studies have shown that the Gly variant (C) is significantly associated with increased susceptibility to sleep bruxism.

Non-genetic Influences on Sleep Bruxism Risk

Sleep bruxism may be accelerated by lifestyle factors as well. Some of them include:
- Stress
- Alcohol consumption
- Anxiety
- Cigarette smoking
- Upper airway resistance
- Caffeine consumption

Effects of Bruxism on Health

1. There is significant damage to the teeth. The teeth can become painful, shaky, and get eroded. Any implants have a risk of getting damaged.
2. It leads to problems with the temporomandibular joint (TMJ) which connects the lower jaw to the skull. This causes locking of the jaw, difficulty with chewing, popping, or clicking noises, and chronic jaw pain.
3. The sound from clenching and grinding your teeth can make it harder for the person you share your bed with to fall asleep.

Tips for Managing Bruxism

Mouth guards - Mouth guards help keep the teeth separated and hence prevent grinding.
Stress management - Stress is one of the major contributors to teeth grinding. So finding ways to alleviate stress can help prevent teeth grinding.
Avoid alcohol and caffeine - Teeth grinding tends to intensify upon alcohol and caffeine consumption.
Avoid chewing on pens and pencils - This practice gets your jaws used to grinding movement and may increase your tendency to grind your teeth.

Summary

1. Sleep Bruxism is defined as repetitive jaw muscle activity during sleep. Over time, it could damage teeth, oral health conditions, facial muscle pain, sleep disturbances, and difficulty while speaking or eating.
2. It is more common in children, adolescents, and young adults than in middle-aged and older adults.
3. Few studies have shown the significant associations of certain variants in neurotransmitters like dopamine, serotonin, and others DRD3, HTR2A, COMT, MMP9, and others with sleep bruxism.
   1. The C allele of rs6280 SNP found in the DRD3 gene, a dopamine receptor, is associated with increased susceptibility to sleep bruxism.
4. As sleep bruxism causes severe damage to the teeth over time and leads to problems with the temporomandibular joint, it needs to be managed. Using mouth guards, avoiding alcohol and caffeine, managing stress, and not chewing on pens and pencils can help.

References

https://pubmed.ncbi.nlm.nih.gov/32471213/
https://pubmed.ncbi.nlm.nih.gov/27611726/
https://pubmed.ncbi.nlm.nih.gov/28451935/
https://pubmed.ncbi.nlm.nih.gov/30092895/
https://pubmed.ncbi.nlm.nih.gov/25628080/

What is Sleep Fragmentation?

Sleep fragmentation is one of the symptoms of sleep disorders characterized by repeated, short sleep interruptions during the night, which leads to excessive tiredness during the day.

People with fragmented sleep tend to fall asleep quickly but wake up multiple times during the night for short periods. The other symptoms of fragmented sleep include morning headaches, daytime sleepiness, difficulty in concentrating, and memory lapses.

Fragmented sleep due to situational illness (like a cough or a sore back)is called short-term sleep fragmentation and goes away after some time.

Research studies have documented a greater impact on physical and emotional health when sleep quality and quantity are poor.

How Does Genetics Influence Sleep Fragmentation Risk?

A study reported the genetic and environmental variance in sleep complaints. The proportions were as follows:
1. At 8 years: 63% genetic, 32% non-shared environment
2. At 10 years: 66% genetic, 27% nonshared environment, 7% shared environment

The study also suggests that genetics affects sleep problems more strongly during the preschool/school age (63-69%) . Certain variants in HLA-DQB1, CRY1, and other genes might influence the risk of having fragmented sleep.

CRY1 and Sleep Fragmentation

The CRY1 gene encodes a protein called flavin adenine dinucleotide-binding, a key component of circadian clock regulation.
Variations in the CRY1 gene are found to be associated with altered sleep patterns.

rs184039278 and Sleep Fragmentation

The rs184039278 is an A>C gain of function mutation located in the CRY1 gene, associated with a prolonged period of circadian molecular rhythms.

A study, Patke, Alina, et al.2017, demonstrated that both CC and AC carriers are strongly associated with late sleep times and sleep fragmentation.

Non-genetic Factors That Influence The Fragmented Sleep Risk

Some sleep-related disorders can result in fragmented sleep. A few examples are:
1. Snoring
2. Obstructive sleep apnea
3. Sleep-maintenance insomnia
4. Restless leg syndrome

Poor sleep is also caused by lifestyle habits such as:
1. Alcohol and caffeine consumption
2. Napping for a long time in the day
3. Exercising close to bedtime

Effects of Sleep Fragmentation on Health

1. Sleep fragmentation reduces the amount of sleep you get at night and leads to extreme fatigue during the day.
2. It leads to a decrease in your concentration and productivity during the day.
3. There is a risk of weight gain and mood-related disorders.
4. It leads to increased stress and has a negative impact on your memory and cognitive function.
5. Over a period of time, there is a risk of heart diseases, obesity, and diabetes.
6. Behavioral problems in children are associated with sleep fragmentation.

Tips for Managing Sleep Fragmentation

You can follow these tips to have a peaceful night of sleep and avoid sleep fragmentation.
1. Tire yourself out: As fatigue accumulates throughout the day, it’ll be easier to fall asleep in the night.
2. Stay away from distractions: Switch off your phone, wear an eye mask, and shut the windows to prevent your sleep from being disturbed.

Summary

1. Sleep fragmentation is characterized by repeated, short sleep interruptions during the night, which leads to excessive tiredness during the day. This has a great impact on physical and emotional health.
2. The CRY1 gene encodes a protein called flavin adenine dinucleotide-binding, a key component of circadian clock regulation. The rs184039278 SNP found in this gene is associated with a prolonged period of circadian molecular rhythms, late sleep times, and sleep fragmentation.
3. Snoring, OSA, RLS, and bad lifestyle habits can also lead to sleep fragmentation.
4. Sleep fragmentation can lead to concentration, productivity, extreme fatigue, mood-related disorders, and other problems.
5. Tiring yourself out and staying away from distractions can help avoid sleep fragmentation.

References

https://pubmed.ncbi.nlm.nih.gov/20975052/
https://pubmed.ncbi.nlm.nih.gov/28388406/
https://pubmed.ncbi.nlm.nih.gov/24179306/