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Sleep disorders affect millions of Americans, disrupting the body's natural sleep-wake cycle and significantly impacting both physical and mental health. The recommended amount of sleep for adults is at least 7 hours each day, yet 40% of Americans are sleep deprived, with 1 in 3 adults not getting enough sleep. These widespread disturbances in sleep patterns can lead to serious consequences for overall well-being, making sleep disorders a critical public health concern.

Understanding sleep disorders is essential because sleep difficulties contribute to a variety of medical problems, including cognitive impairment, reduced immune function, metabolic imbalance, and exacerbation of psychiatric conditions. The relationship between sleep and mental health is particularly strong, with research showing that those with insomnia are roughly ten times as likely to have major depressive disorder as healthy controls without sleep disorders. This bidirectional relationship means that addressing sleep issues is crucial for both preventing and treating mental health conditions.

Table of Contents

  • Types of Sleep Disorders
  • Symptoms of Sleep-Wake Disorders
  • Sleep Disorders and Mental Health
  • Medical Concerns Linked to Sleep Disorders
  • Treatment Options for Sleep Disorders
  • Frequently Asked Questions
  • How Therapy Can Help / Find a Therapist

Types of Sleep Disorders

The International Classification of Sleep Disorders (ICSD) helps provide a standardized classification and definitions for sleep disorders. The DSM-5-TR recognizes eleven main categories of sleep-wake disorders, reflecting that coexisting medical conditions, mental disorders, and sleep disorders are interactive and bidirectional:

Insomnia Disorder

Insomnia, the most common sleep disorder, involves problems getting to sleep or staying asleep. About one-third of adults report some insomnia symptoms, 10 to 15% report problems with functioning during the daytime, and 4 to 22% have symptoms severe enough to meet criteria for insomnia disorder. The diagnostic criteria require frequency criteria, and the duration has been changed to 3 months.

Hypersomnolence Disorder

This disorder involves self-reported excessive need for sleep despite sleeping for at least 7 hours and having at least one of the following symptoms: recurrent periods of sleep or an irrepressible need to sleep within the same day.

Narcolepsy

One in every 2,000 adults has narcolepsy. This chronic neurological disorder affects the brain's ability to control sleep-wake cycles, often causing sudden episodes of sleep during normal waking hours.

Breathing-Related Sleep Disorders

Sleep apnea affects about 10% of the population. These disorders include:

  • Obstructive sleep apnea hypopnea
  • Central sleep apnea
  • Sleep-related hypoventilation

Circadian Rhythm Sleep-Wake Disorders

These include disorders where the timing of sleep is misaligned with the environment or social/work demands:

  • Delayed sleep phase type
  • Advanced sleep phase type
  • Irregular sleep-wake type
  • Non-24-hour sleep-wake type
  • Shift work type

Non-Rapid Eye Movement (NREM) Sleep Arousal Disorders

DSM-5 divides NREM sleep arousal disorders into sleepwalking type and sleep terror type, which involve incomplete awakening from sleep accompanied by either sleepwalking or sleep terrors.

Nightmare Disorder

Characterized by repeated occurrences of extended, dysphoric, and well-remembered dreams that usually involve threats to survival, security, or physical integrity.

Rapid Eye Movement (REM) Sleep Behavior Disorder

These have been designated as independent disorders. In DSM-IV-TR, they were included under dyssomnia not otherwise specified. This disorder involves acting out dreams during REM sleep.

Restless Legs Syndrome

Restless legs syndrome (RLS) affects 5% to 10% of adults and 2% to 4% of children. It causes uncomfortable sensations in the legs and an irresistible urge to move them.

Substance/Medication-Induced Sleep Disorder

Sleep disturbances that are a direct physiological consequence of a drug of abuse, medication, or toxin exposure.

Symptoms of Sleep-Wake Disorders

The manifestations of sleep disorders extend beyond nighttime difficulties. Common symptoms include:

Nighttime Symptoms:

  • Difficulty falling asleep (sleep onset insomnia)
  • Frequent awakening during the night
  • Early morning awakening with inability to return to sleep
  • Non-restorative sleep despite adequate time in bed
  • Abnormal behaviors during sleep (sleepwalking, sleep talking)- Common sleep disturbances in childhood include nightmares (60%), snoring (44%), and teeth grinding (41%)

Daytime Symptoms:

  • Excessive daytime sleepiness
  • Fatigue and low energy
  • Difficulty concentrating or focusing
  • Memory problems
  • Mood changes, including irritability
  • Reduced performance at work or school
  • Increased risk of accidents

Overall, 14.5% of adults had trouble falling asleep and 17.8% of adults had trouble staying asleep. With increasing age, adults were less likely to have trouble falling asleep but more likely to have trouble staying asleep. Women were more likely than men to have trouble both falling and staying asleep.

Sleep Disorders and Mental Health

The relationship between sleep disorders and mental health is complex and bidirectional. Sleep architecture disruption, occurring through both quantity, quality, and timing of sleep as well as through the presence of sleep disorders, may both influence mental health and well-being as well as be disrupted by both physical and mental health conditions.

Depression and Sleep

Individuals with insomnia are 10 times more likely to exhibit clinical depression and 17 times more likely to show anxiety than are non-insomniacs. A meta-analysis of 21 longitudinal studies showed baseline insomnia doubles the risk of developing depression. The relationship is bidirectional:

  • People with depression often experience hypersomnia (oversleeping) or insomnia
  • Poor sleep quality can trigger or worsen depressive episodes- Improving sleep significantly reduced depression (MD, -2.92; 95% CI, -3.61 to -2.24, P-value < 0.001) and anxiety (MD, -1.14; 95% CI, -1.32 to -0.97, P-value < 0.001) compared to standard care among adults

Anxiety Disorders

"Stress and anxiety can significantly disrupt sleep patterns by triggering the body's fight-or-flight response, making it difficult to relax. When the mind is racing with worries, it becomes nearly impossible to achieve the deep, restorative sleep we need for overall health." The survey also found that over half of Americans (55%) report sometimes, always, or often experiencing disrupted sleep due to depression.

Stress and Sleep

Stress is more likely to cause disrupted sleep in people aged 18–24 (62%), and stress-related sleep disruptions become less common with age. The impact includes:

  • Increased cortisol levels disrupting sleep architecture
  • Racing thoughts preventing sleep onset
  • Physical tension affecting sleep quality

Bipolar Disorder

People with bipolar disorder commonly experience:

  • Reduced need for sleep during manic episodes
  • Hypersomnia during depressive episodes
  • Sleep disturbances that may trigger mood episodes

Substance Use Disorders

The relationship between sleep and substance use is complex:- Chronic sleep issues may cause someone to misuse substances to prompt sleep. Substances like alcohol can help people fall asleep but can greatly reduce the benefits of sleep

  • Withdrawal from substances often causes severe sleep disturbances
  • Poor sleep can increase vulnerability to relapse

PTSD and Sleep

Several studies employing polysomnography have attempted to characterize the neurophysiologic changes in sleep in those with schizophrenia and have identified the following differences from healthy controls: increased latency to sleep onset, increased wake time during the night, decreased total sleep time. Nightmares and hypervigilance are common features that disrupt sleep in PTSD.

Neurodevelopmental Conditions

Cognitive Behavioural Therapy for insomnia (CBT-I) is the recommended first-line treatment for chronic insomnia disorder in diverse populations with co-occurring conditions. However, individuals with neurodevelopmental conditions are frequently excluded from CBT-I research, despite the high prevalence of sleep problems in this population.

Medical Concerns Linked to Sleep Disorders

Sleep disorders are associated with numerous medical conditions, creating a complex web of health concerns:

Cardiovascular Health

Adults who were short sleepers (less than 7 hours per 24-hour period) were more likely to report 10 chronic health conditions compared to those who got enough sleep (7 or more hours per 24-hour period), including:

  • Hypertension
  • Coronary heart disease
  • Stroke
  • Irregular heart rhythms

Metabolic Disorders

  • Type 2 diabetes
  • Obesity
  • Metabolic syndrome- Women who sleep less than 5 hours have a 15% higher risk of becoming obese compared to women who sleep 7 hours

Neurological Conditions

Both short sleep duration (< 7 h; RR = 1.27) and long sleep duration (> 8 h; RR = 1.23 for cognitive decline, RR = 1.43 for all-cause dementia, and RR = 1.66 for Alzheimer's disease (AD)) were significant risk factors for cognitive decline and dementia. Excessive daytime sleepiness significantly increased the risks of vascular dementia (VD) (RR = 1.85), all-cause dementia (RR = 1.41), and cognitive decline (RR = 1.37). Sleep-related movement disorders indicated the strongest association, markedly increasing the risk of VD (RR = 2.53). Poor sleep quality was also a significant risk factor for AD (RR = 1.24), all-cause dementia (RR = 1.17), and cognitive decline (RR = 1.18).

Immune Function

Sleep deprivation weakens the immune system, increasing susceptibility to:

  • Infections
  • Slower wound healing
  • Reduced vaccine effectiveness

Chronic Pain Conditions

  • Fibromyalgia
  • Arthritis
  • Chronic headaches- Pain did not meaningfully hinder the effects of CBT-I on sleep outcomes. Among older veterans with chronic insomnia disorder, individuals with higher pain exhibited slightly greater improvement in insomnia than those with lower levels of pain

Respiratory Disorders

  • Asthma exacerbations
  • Chronic obstructive pulmonary disease (COPD) complications

Treatment Options for Sleep Disorders

Cognitive Behavioral Therapy for Insomnia (CBT-I)

When these techniques are used together as multicomponent CBT-I, as many as 70% to 80% of patients with primary insomnia experience improvements. CBT-I is considered the gold-standard treatment for chronic insomnia:

Key Components:- The most efficacious combination—consisting of cognitive restructuring, third wave, sleep restriction, and stimulus control in the in-person format—compared with in-person psychoeducation, was associated with an increase in the remission rate by a risk difference of 0.33 (95% CI, 0.23-0.43) and a number needed to treat of 3.0 (95% CI, 2.3-4.3)

  • Sleep hygiene education
  • Relaxation techniques
  • Sleep diary monitoring

Effectiveness:- According to meta-analytic estimates, the average treatment effect sizes range from 1.0–1.2, which corresponds to approximately a 50% post-treatment reduction in insomnia symptoms- A 2015 meta-analysis of 20 randomized controlled studies of CBT-I for patients with chronic insomnia found average reductions of 19 minutes in sleep latency and 26 minutes in time awake after sleep onset. Total sleep time improved by 8 minutes, and sleep efficiency improved by 10%. CBT-I produces results that are equivalent to sleep medication, with no side effects, fewer episodes of relapse, and a tendency for sleep to continue to improve long past the end of treatment

Digital CBT-I (dCBT-I)

SleepioRx is an FDA-cleared digital CBT-I intervention for the treatment of insomnia disorder that can be accessed on the order of a licensed health care provider. The program delivers cognitive (e.g., cognitive restructuring and paradoxical intention), behavioral (e.g., stimulus control, sleep restriction, and sleep hygiene), and physiological (e.g., progressive muscle relaxation) techniques. SleepioRx techniques are delivered through audio, visual, and interactive elements, without any human coaching or assistance. Patient experience is tailored based on interactive features within the treatment, as well as daily sleep diaries.

DCBT-I showed no statistically significant differences from active controls, indicating comparable effects with therapist-delivered CBT-I. In contrast, it demonstrated statistically significant effects against inactive controls: TST increased by 0.20 h, SOL decreased by 15.53 min, SE improved by 7.91%, WASO reduced by 15.61 min, and NWAK decreased by 0.53.

Pharmacological Treatments

Yue et al.: Efficacy and tolerability of pharmacological treatments for insomnia in adults: A systematic review and network meta-analysis found various medications can be effective:

  • Prescription Sleep Medications: Including benzodiazepines, non-benzodiazepine hypnotics, and orexin receptor antagonists
  • Antidepressants: Some antidepressants are also used to treat insomnia
  • Melatonin and Melatonin Receptor Agonists: For circadian rhythm disorders- About 6% of Americans take medication every day to help improve their sleep. Women and older adults are more likely to take sleep medication

Non-Pharmacological Interventions

Regarding non-pharmacological interventions, there is good evidence for physical activity and for CPAP amongst those with sleep-disordered breathing. Trazodone and the orexin-receptor antagonists are the pharmacological interventions with the best evidence to support their effectiveness in treating sleep disturbances in people with cognitive impairment.

Additional interventions include:

  • Light Therapy: For circadian rhythm disorders
  • Sleep Hygiene Education: Establishing healthy sleep habits
  • Mindfulness and Relaxation: There were significantly different effect sizes found between studies that evaluated cognitive behaviour therapy for insomnia (CBT-I; n = 6, g = 0.72, CI: 0.43–1.02) versus studies that evaluated mindfulness interventions (n = 5, g = 0.16, 95% CI: -0.18–0.51)
  • Continuous Positive Airway Pressure (CPAP): For sleep apnea

Treatment Considerations

DSM-5 underscores the need for independent clinical attention of a sleep disorder regardless of mental or other medical problems that may be present. Important factors include:

  • Cost-Effectiveness: The incremental cost-utility ratios and incremental cost-effectiveness ratios showed that the CBTI and dCBTI groups were more cost-effective than controls, from healthcare perspective and societal perspective, respectively. Compared to controls, CBTI demonstrated significantly better efficacy within 12 months
  • Accessibility: Digital interventions are expanding access to evidence-based treatments
  • Personalization: Treatment should be tailored to individual needs and co-occurring conditions

Frequently Asked Questions

What is the most common sleep disorder?

Insomnia, the most common sleep disorder, involves problems getting to sleep or staying asleep. About one-third of adults report some insomnia symptoms. It affects people of all ages but becomes more prevalent with age and is more common in women than men.

How many hours of sleep do adults need?

The recommended amount of sleep for adults is at least 7 hours each day. However, individual needs may vary slightly. Quality of sleep is just as important as quantity—restorative sleep that includes all sleep stages is essential for health.

Can sleep disorders cause mental health problems?

Yes, the evidence that sleep disturbances are associated with an increased risk of developing psychiatric disorders has existed since the 1980s. In terms of MDD, this evidence includes that those with insomnia and those with hypersomnia are roughly ten times as likely to have MDD as healthy controls without sleep disorders. Sleep problems can both trigger and worsen mental health conditions.

Is CBT-I effective for everyone with insomnia?

When these techniques are used together as multicomponent CBT-I, as many as 70% to 80% of patients with primary insomnia experience improvements. While highly effective for many, some individuals may need additional or alternative treatments, especially those with complex medical conditions.

How long does it take for sleep treatments to work?

CBT-I typically shows improvements within 4-8 weeks, with a tendency for sleep to continue to improve long past the end of treatment. Medications may work more quickly but often don't provide lasting benefits after discontinuation.

Should I see a doctor for my sleep problems?

Yes, if sleep problems persist for more than a few weeks or significantly impact your daily life. DSM-5 and ICSD-3 insomnia diagnostic criteria are similar because of collaborative efforts between the American Psychiatric Association and the American Academy of Sleep Medicine. Insomnia is a disorder in itself that needs independent clinical attention.

How Therapy Can Help / Find a Therapist

Sleep disorders can significantly impact your quality of life, but effective treatments are available. A qualified therapist can help you:

  • Identify underlying causes of your sleep difficulties
  • Learn evidence-based techniques like CBT-I to improve sleep
  • Address co-occurring mental health conditions that may be affecting your sleep
  • Develop healthy sleep habits and routines
  • Process emotional factors contributing to sleep problems

Working with a therapist who specializes in sleep disorders or behavioral sleep medicine can be particularly beneficial. They can provide personalized treatment plans that address your specific sleep challenges while considering your overall mental and physical health.

Find a Therapist Through GoodTherapy

If you're struggling with sleep problems, consider reaching out to a qualified mental health professional. The GoodTherapy directory can help you find therapists in your area who specialize in:

  • Sleep disorders and insomnia
  • Cognitive Behavioral Therapy for Insomnia (CBT-I)
  • Co-occurring sleep and mental health conditions
  • Behavioral sleep medicine

Don't let sleep problems continue to affect your well-being. Take the first step toward better sleep and improved mental health by connecting with a therapist who can help you develop effective strategies for managing your sleep difficulties.

Search for a sleep specialist in your area →

Remember, sleep disorders should be specifically addressed regardless of mental or other medical problems that may be present. Chronic insomnia is typically treated with a combination of sleep medications and behavioral techniques, such as cognitive behavior therapy. With proper treatment and support, most people can significantly improve their sleep and overall quality of life.

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