Forms of insomnia
According to the International Classification of Sleep Disorders, 3rd Edition (ICSD-3), insomnia is classed as one of the following types: (5)
- Short-term Insomnia: Sleep challenges are associated with an identifiable stressor – once the stressor is sufficiently resolved, problems with insomnia will often subside. A person struggles with falling asleep or maintaining a sleep state and is not deprived of an opportunity to sleep. Symptoms are experienced for a period of up to 3 months. Symptoms experienced over a period of a few days or weeks also fall under this type of insomnia.
- Chronic Insomnia (formerly primary and secondary or comorbid insomnia – now a consolidated classification): Classified as a single disorder known as ‘chronic insomnia disorder’. A person has challenges with ‘sleep initiation’ or ‘sleep maintenance’ even though he / she has sufficient opportunity to achieve sleep. Symptoms are experienced at least 3 times a week for at least 3 months (or longer).
- Other: A person is symptomatic but cannot be categorised distinctly as having either ‘short-term’ or ‘chronic’ insomnia.
1. Short-term Insomnia Disorder (also known as acute / adjustment insomnia)
Short-term insomnia is generally defined as sleep disturbance that occurs over several days or even weeks. A clinical diagnosis is made if a person is symptomatic for less than a 3-month period.
Symptoms arise, most often, due to a stressor which can be identified as psychological, psychosocial, interpersonal or physical.
Stressors are events or circumstances which cause enough distress to a person (i.e. an acute situational stress), thereby impacting their ability to sleep soundly. Such circumstances can include things such as the loss of a job, a couple going through a separation or divorce, or the death of a loved one.
Other stress-related triggers can include:
- Stress (mental stress) and persistent pressure within the home, an educational environment or workplace (including lengthy and disruptive work schedules)
- Anxiousness regarding an upcoming event, such as taking up a new job, or relating to an upcoming deadline or examination (test)
- Worry over problems that arise within the family – such as mounting issues with debt or other financial concerns
- Traumatic events (such as a recent surgical procedure or experiencing an illness or injury)
Since a stressor is at the root of sleep disruption, taking action to resolve the distressing circumstance normally helps to relieve insomnia (i.e. sufferers may experience less frequent bouts of insomnia or the condition may resolve completely). Actions can include effective coping mechanisms or learning to better manage a challenging situation. Failure to resolve stressors can, however, result in persistent sleep issues, which in turn may worsen and become chronic. Short-term insomnia can recur when new or similar types of stressors occur again sometime down the line in a person’s life.
2. Chronic Insomnia Disorder
The main diagnostic criteria for chronic conditions are symptoms which have occurred for at least 3 months with bouts of insomnia taking place no fewer than 3 times a week. For many individuals, medical intervention may only be sought after suffering from persistent symptoms for many months or even years.
A particularly stressful event may initially trigger the symptoms of insomnia. Along with chronic insomnia symptoms, behavioural and adjustment difficulties within professional and social settings affect individuals with persistently poor sleep habits. Affected individuals tend to experience consistent worry and anxiety regarding the impact their poor sleep will have on their ability to function and perform sufficiently. The result is a worsening cycle of insomnia symptoms, elevating levels of stress.
Chronic insomnia typically follows a prolonged period of stress in a person’s life. Generally, these individuals were previously able to achieve restorative / adequate sleep quality. As a result of prolonged stress, the sufferer’s body responds by converting the resulting tension or anxiety into physical symptoms.
Sleep disturbances are typically reinforced in an individual who experiences frequent poor-quality sleep. In a way, the person “learns” to become anxious and worrisome regarding sleep, creating conditioned sleep difficulties. The more a person worries about being able to achieve sleep, and particularly at the time when it should be occurring, the higher the risk of not being able to reach a sleep state. If this happens and sleep disturbances are reinforced, a person can easily develop chronic insomnia.
Factors which a doctor will look out for when assessing conditioned sleep difficulties include:
- An increased / excessive focus on sleep or a heightened anxiety regarding sleep.
- Difficulties initiating sleep at bedtime, or even during a planned nap.
- Little difficulty falling asleep at a time when not intending to, or during a monotonous activity.
- Little difficulty being able to sleep when away from home.
- Frequent occurrences of mental arousal (i.e. an active or racing mind with intrusive thoughts).
- Difficulties with relaxing the body while in bed which prevent the onset of sleep.
Psychosocial stressors, as well as medical or psychiatric conditions and disorders are associated with chronic insomnia problems.
Insomnia relating to a medication, drug or other substance
Sleep disruptions can also occur as a result of substance use or abuse. Excessive use of certain stimulants, such as sedative-hypnotics, caffeine, nicotine or alcohol can result in sleep related difficulties during periods of use / exposure and / or withdrawal stages.
Insomnia may thus be experienced as a side-effect of exposure to a specific substance (medication, toxin or foodstuff), or in those who display a current and ongoing dependence to a specific drug that is known to have disruptive capabilities (i.e. substance abuse or addiction to drugs such as cocaine and methamphetamine).
Some prescription medications which are known to cause side-effects of insomnia include:
- Theophylline (for the treatment of asthma or chronic obstructive pulmonary disease),
- Medications used to treat colds and flu and allergies (like decongestants)
- Beta blockers like Lopressor and others as well as medications used to manage heart conditions.
Sleep disorders resulting in insomnia symptoms
An underlying sleeping disorder can result in symptoms of insomnia. Common disorders and problems which cause sleep disturbances associated with insomnia include:
- Restless leg syndrome: An overwhelming urge to move the legs, particularly during the night, accompanied by leg twitching and cramping. Symptoms are most prevalent during periods of inactivity and rest (more frequently during the night) and can be somewhat relieved by movement that involves stretching or walking. This condition is associated with PLMD (periodic limb movement disorder) whereby periodic leg movements occur during the night while the sufferer is asleep. A person with restless legs syndrome typically struggles with falling asleep while a person with PLMD is likely to have more trouble with maintaining sleep than falling asleep.
- Obstructive sleep apnoea: Intermittent blockages of airflow during sleep characterise this condition, which can cause difficulty in maintaining sleep throughout the night. Some may also experience awakening problems during the night due to excessive urination urges (a condition which is medically referred to as nocturia / nocturnal polyuria).
- Circadian rhythm disorders: Common problems relating to sleep-wake cycles include:
- Advanced sleep phase syndrome - a person feels sleepy earlier than their normal bedtime and often awakens before they would normally like to.
- Delayed sleep phase syndrome - a person feels sleepy much later than their normal bedtime and typically awakens later the following day too – this is most typical of adolescents.
- Shift-work sleep disorder - excessive sleepiness and symptoms of insomnia are common in those with a recurring work schedule that overlaps a normal sleep time – completely or partially, whether early in the morning or those that end late into the night. Those who work night shift most often struggle with falling sleep and maintaining a state of sleep thereafter. Sunlight exposure prior to retiring to bed following shift work can be disruptive to the sleep process, causing insomnia. Social and environmental factors can also disrupt sleep should there be obligations, errands and commitments that need to be performed during the daylight hours, such as fetching children from school.
- Irregular sleep-wake rhythm – Individuals with poor sleep hygiene generally have trouble with getting adequate sleep. Risk factors include individuals who live alone, work alone or have little exposure to light or outside activity. Individuals with dementia or other neurodegenerative disorders are also prone to irregular sleep-wake rhythms. Some also struggle with developing habitual bedtimes as they frequently (and randomly) take naps during daytime hours.
Insomnia relating to a medical condition
An underlying medical condition can bring about symptoms of insomnia. Some of these include:
- Advanced chronic obstructive lung disease
- Benign prostatic hypertrophy
- Conditions associated with breathing difficulties such as asthma
- Chronic fatigue syndrome
- Chronic renal disease
- Gastrointestinal upsets such as heartburn and acid reflux
- Heart failure
- Hormonal imbalances, resulting in menopause or hyperthyroidism (overactive thyroid)
- Hypertension (high blood pressure)
- Neurological disorders such as Parkinson’s disease and headache conditions (particularly cluster headaches)
Common underlying difficulties that can arise include problems with breathing, chronic pain, urinary issues and neurological challenges.
Insomnia relating to a mental disorder / illness
Many chronic mental or psychiatric disorders display symptoms of sleep disturbances. Early morning awakenings are frequently experienced by those suffering from depression, and as such as been closely associated with insomnia. Depressed individuals have difficulty in falling back to sleep too. Those who experience chronic insomnia for at least a year are also at higher risk of developing depression.
Difficulties in falling asleep are frequently seen in individuals with schizophrenia and during the manic phases of bipolar disorder. Initiating and maintaining a sleep state is common among those with anxiety disorders, including post-traumatic stress disorder (PTSD) and nocturnal panic disorder (panic attacks experienced at night, awakening a person from a sleep state), as well as those with Alzheimer’s disease.
An official diagnosis of a mental health or psychiatric condition must be identified according to relevant diagnostic criteria. Insomnia may be temporary, sometimes occurring for several days or weeks before the onset of an underlying condition or disorder.
A person experiencing insomnia, along with a mental disorder will show signs of marked distress requiring specific or targeted treatment measures involving psychotherapies and pharmacological aids.
Behavioural insomnia of childhood
Sleep disturbances affecting children most often relate to trouble falling asleep (sometimes referred to as sleep-onset association) or limit-setting behavioural problems.
Trouble with initiating sleep may be characterised by:
- Difficulty falling asleep without the implementation of special conditions.
- Delayed sleep initiation if special conditions are not implemented. It can often be a time-consuming and challenging process to get the child to fall asleep as a result.
- Frequent night-time awakenings - a child may only be able to return to sleep with the direct intervention of a caregiver or parent.
Limit-setting behavioural problems may be characterised by:
- Difficulties with maintaining a state of sleep, as well as falling asleep.
- Stalling or refusal behaviours. A child may refuse or stall going to bed at the relevant time, or after having awoken during the night.
- A caregiver or parent not establishing appropriate or sufficient limits or boundaries for a child to develop normal / healthy sleeping behaviour.
All of the above-mentioned types of insomnia can bring about daytime fatigue and sleepiness (or drowsiness) as well as a lack of energy, particularly during waking hours. This impacts the sufferer’s ability to focus sufficiently, concentrate, learn and retain new information (memory function), as well as apply themselves accordingly.
Affected individuals may also develop depressive and anxious moods, becoming frequently irritable. As a result, such disruptions can negatively impact their quality of life, as well as that of those around them. Many also display slower responses to tasks which challenge normal reaction times. This too can have an impact on a person’s social, academic or occupational performance.
5. European Sleep Research Society. 2014. Assessment of sleep disorders and diagnostic procedures: https://www.esrs.eu/fileadmin/user_upload/publications/ESRS_Sleep_Medicine_Textbook_Chapter_B1.pdf [Accessed 04.08.2018]