Sleep Disorders

Understanding Sleep Disorders

Sleep disorders, also known as sleep-wake disorders, involve conditions that disrupt the natural sleep cycle. They are characterized by problems with sleep duration, quality, and timing. They can be severe enough to affect a person’s physical and mental health, social functioning, and overall quality of life.

Types of Sleep Disorders

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), recognizes the following types of sleep disorders:

• Insomnia
• Hypersomnolence disorder
• Narcolepsy
• Breathing-related sleep disorders
• Circadian Rhythm Disorders
• Sleep Apnea
• Parasomnias
• Restless Legs Syndrome
• Substance/medication-induced sleep disorder

Understanding Insomnia

Insomnia disorder is characterized by difficulty initiating or maintaining sleep, occurring at least three times a week for three months or more, affecting daytime functioning or well-being, as defined in the DSM-5.

How Insomnia Impacts Daily Life

Insomnia is associated with daytime impairments such as fatigue, mood disturbances, interpersonal issues, cognitive decline, reduced performance, hyperactivity, impulsivity, aggression, and a lack of motivation. In addition, a person may be more prone to making mistakes or accidents which cause distress or interfere with daily life.

Fatigue vs. Sleepiness

Individuals with insomnia often experience fatigue (extreme tiredness and a lack of energy) rather than sleepiness (a tendency to fall asleep).

A study by Fortier-Brochu et al., which examined how sleep issues and fatigue affect people with chronic insomnia, found that severe sleep problems don’t always lead to more fatigue. People with more fatigue had a lower quality of life, but those with severe sleep issues and similar fatigue levels were even more affected. Younger people and those with depression had worse outcomes across these areas. Interestingly, the sleep quality perceived by participants was more closely connected to fatigue than actual sleep length or continuity. Individual variations, as well as characteristics such as arousal levels and depressive symptoms, appear to play a role in how sleep problems and weariness are experienced.[i]

Hyperarousal

People with insomnia often feel constantly alert or tense, even during sleep, which disrupts their ability to rest properly. This heightened state of alertness, or hyperarousal might be linked to both genetic factors and experiences early in life, like childhood stress or trauma.

Emotional Reactivity and Regulation

Research indicates that insomnia may cause individuals to become more emotionally reactive, particularly to sleep-related stimuli. However, those with insomnia might perceive emotional expressions on faces as less intense, likely because of the influence of anxiety and depression. Kyle et al. explored how insomnia affects emotional processing at the neural level. Their study suggests that insomnia might affect how people process emotions, potentially due to changes in the brain regions involved in emotion regulation, such as the amygdala. In this study, researchers explored how people with primary insomnia (sleeplessness without medical, psychiatric, or environmental causes) process emotional information differently than good sleepers.

They found that while both groups could generally recognize emotions in facial expressions, those with insomnia rated the intensity of emotions, particularly fear and sadness, as less intense. This “emotional blunting” might be linked to changes in brain function due to insomnia. However, the study did not find a direct connection between sleepiness or sleep quality and these emotional responses. Instead, anxiety and depression were more closely associated with how people with insomnia perceived emotional intensity.[ii]

Factors Influencing Insomnia Development

The onset of insomnia is thought to be a complex interplay of cognitive, physiological, psychological, and environmental factors. These factors such as genetics, early life stress, major life events, and brain structure and function are often triggered by stress or life events. Moreover, they are often preserved by maladaptive behaviors and thought .

Genetic and Early Life Influences

Insomnia risk can stem from genetic predispositions present from birth. These genetic factors might be influenced by stressful experiences during childhood, which can make the brain more sensitive to stress and contribute to insomnia later in life. Namely, adverse early-life experiences, such as trauma or stress, can have long-lasting effects on how the brain reacts to stress and handles sleep, potentially setting the stage for insomnia.

Brain Activity and Sleep

Usually, certain brain areas quiet down during sleep to help the body rest. In people with insomnia, these areas, especially those involved in emotions and alertness, remain more active than usual, disrupting sleep.

Recent research suggests that insomnia is closely linked to how the brain manages emotions and arousal rather than simply being a disorder of sleep regulation Studies suggest that individuals with insomnia often exhibit heightened levels of emotional reactivity and hyperarousal, which can persist throughout the day and not just at night. For example, research has shown that the amygdala, a key brain structure involved in emotional processing, does not reduce its reactivity overnight as effectively in people with insomnia. This failure to “calm down” after emotional stimulation during the day is a core factor in the persistence of insomnia symptoms.

Additionally, studies using resting-state functional MRI (RS-fMRI) have found that people with insomnia show abnormal connectivity between brain regions involved in emotion regulation, such as the hippocampus and the default mode network (DMN). This shows that the brain’s systems for regulating stress and emotions are disrupted in people with insomnia, causing them to be constantly alert.

Insomnia may involve altered brain activity in regions like the locus coeruleus, which plays a key role in arousal and emotional regulation. This hyperactivity can lead to a heightened state of alertness, even during sleep, contributing to the persistent cycle of insomnia and associated emotional distress. A study by Li et al. showed that patients with chronic insomnia had increased connectivity between the locus coeruleus and key regions of the brain’s default mode network, which is associated with maintaining wakefulness and consciousness.[iii]

Prevalence and Risk Factors

Insomnia is prevalent in about one-third of people at some point in their lives, with a diagnosis applied if sleep issues affect daytime functioning.

According to the American Academy of Sleep Medicine, around 30% of adults in the United States experience insomnia symptoms, with 10% having severe insomnia that interferes with daily activities. At the same time, less than 10% of individuals are likely to experience persistent insomnia. Sleep complaints peak during puberty and later life, with insomnia being more common in women, possibly due to hormonal fluctuations, and increases with age.

Risk Factors Associated with Untreated Insomnia

Consistent lack of sleep can negatively affect all body systems, including the brain, heart, and immune system. Those whose insomnia remains untreated may suffer from various mental health issues, ranging from irritability and heightened stress sensitivity to more serious psychological conditions such as depression. Additionally, inadequate sleep raises the risk of chronic health conditions such as diabetes, kidney disease, stroke, heart disease, and obesity.

One study indicated that people in their 50s and 60s who sleep six hours or less per night have a 30% higher risk of developing dementia compared to those who get seven hours of sleep​.

Insomnia also affects cognitive functions such as attention, memory, and problem-solving abilities. It can lead to neurocognitive deficits, impairing daily functioning and reducing overall productivity.

Moreover, chronic sleep deprivation is linked to an increased risk of mortality, as it contributes to various chronic conditions like obesity and diabetes, which can lead to life-threatening complications​.

Mental Health Issues Associated with Insomnia

Although insomnia can be a symptom of a psychiatric condition or an independent disorder, it is most frequently observed as a comorbid condition with another medical condition or mental disorder. For instance, 40%-50% of individuals with insomnia also experience a comorbid mental disorder like depression, anxiety, or cognitive disorders.

Insomnia and Mood disorders

Insomnia is commonly linked to mood disorders, with a high prevalence among individuals experiencing anxiety and depression.

Symptoms of insomnia are prevalent in about 70-80% of people who experience anxiety. Insomnia is a key feature of anxiety-related disorders, such as Generalized Anxiety Disorder (GAD) and Post-Traumatic Stress Disorder (PTSD).[iv]

However, this relationship is bidirectional as insomnia can both contribute to the development of these mood disorders and be a symptom of them. For example, the lack of restorative sleep can worsen feelings of anxiety and depression, creating a cycle that makes both conditions harder to treat.

Insomnia Treatment

Therapy

The treatment of insomnia often includes a combination of behavioral therapies and medications. Cognitive Behavioral Therapy for Insomnia (CBT-I) is considered a first-line treatment. CBT-I focuses on changing sleep habits and misconceptions about sleep to improve sleep quality without medication.

Pharmacological Options

Pharmacological treatment of insomnia typically includes several classes of medication due to their different mechanisms of action.

Hypnotics, such as benzodiazepines (e.g., temazepam) and non-benzodiazepine sedative-hypnotics (e.g., zolpidem), are commonly prescribed for short-term management due to their efficacy in inducing sleep.

Melatonin receptor agonists like ramelteon mimic the natural sleep hormone melatonin, helping regulate sleep-wake cycles.

Off-label options, such as trazodone, an antidepressant, are sometimes used for their sedative properties.

There are also FDA-approved medications specifically for insomnia, such as suvorexant, a dual orexin receptor antagonist, which blocks the chemicals that promote wakefulness​.

How We Can Help

Pharmacological Measures: Treatment for insomnia may include medications tailored to the individual’s needs.

Therapy: Providing forms of psychotherapy such as CBT-I to address insomnia.

Referrals: Referral to a sleep specialist may be recommended for additional testing such as ruling out obstructive sleep apnea.

Remember—seeking professional help is crucial when experiencing mental health symptoms. Therapists, psychiatrists, counselors, and support groups can offer guidance and support tailored to individual needs. Seeking help is a sign of strength, and prioritizing mental well-being is essential for a healthier and happier future.