“A ruffled mind makes a restless pillow.”
– Charlotte Brontë
What is insomnia?
The word “insomnia” comes from the Latin words “in” (no) and “Somnus”. In Roman mythology Somnus is the god of sleep.
A very short and simple answer to the question above is that insomnia is difficulty with sleeping, and it may involve difficulty falling asleep and/or difficulty staying asleep. Most people suffer from some form of sleep disturbance from time to time. This is often due to a period of anxiety as a result of a stressful life event and is sometimes referred to as acute insomnia.
A few nights of not being able to sleep well is a common reason for visiting a GP to request a prescription for sleeping pills or visiting a community pharmacy to buy a pack of non-prescription (over-the-counter) pills. However, most people who start taking sleeping pills don’t meet the diagnostic criteria for chronic insomnia when they start taking them. For short-term insomnia, taking pills to help you sleep may be the exactly the wrong thing to do because it can often result in further sleeping problems. In addition, there are dangers associated with taking them on an ongoing basis, particularly in the case of prescription pills.
What causes insomnia?
The answer to this question will vary from individual to individual and it isn’t always possible to identify a definite cause or causes. Often many factors combine to cause and maintain insomnia. However, there are several questions you can ask yourself which can help identify clues that may help you determine the possible cause or causes that may apply to you. These questions could include the following:
- Do you have any medical conditions that might be interfering with your sleep?
- Do you do your best to go to bed and get up around the same times every day?
- Are you subject to a lot of stress in your life?
- Do you suffer a lot from worry or anxiety?
- Are you depressed?
- Could consumption (amount and timing) of alcohol, caffeine, nicotine, or food be a factor?
- Are you taking any prescription medicines or over-the-counter medications that might be interfering with your sleep?
- Is your sleep environment quiet, comfortable, dark, cool, and free from distractions?
- Have you suffered a traumatic experience in the recent past?
Generally, insomnia is associated with another problem and it’s rare for it not to be caused or exacerbated by other factors. The most common other factors that could be linked to insomnia are:
Stress and anxiety
Insomnia is very closely related to stress and anxiety in that:
- Anxiety is one of the most powerful disrupters of sleep.
- Insomnia is one of the first signs of anxiety and stress
- Major stressful life events are the most common causes of insomnia.
- Most people have a harder time sleeping on stressful days.
- Anxiety plays a primary role in the development of chronic insomnia. This happens because negative thoughts can set off negative emotions that then cause insomnia.
- Stress and anxiety speed up your brain waves and makes your heart rate and breathing rate more active.
- Stress and anxiety reduce deep sleep, which results in lighter, more restless sleep.
- Stress that occurs during the day raises stress hormone levels in the body, even at night.
Stressors can range from relatively minor things like work deadlines to more serious things like personal health, finances, divorce, death or illness of a loved one, job loss or fear of job loss. Any of these could lead to insomnia by keeping your mind active at night. Having difficulty sleeping can make anxiety worse and create a vicious cycle.
Anxiety symptoms that can lead to insomnia include:
- Worrying about future events
- Ruminating on past events
- Body tension
- Feeling overburdened by responsibilities
- Feeling over-stimulated
Other sleep disorders
Insomnia itself is a sleep disorder. However, it can also be a symptom of another sleep disorder, such as one of the following:
Sleep apnoea – The periodic cessations of breathing that are characteristic of sleep apnoea, leads to a drop in the body and brain’s oxygen levels causing the individual to wake up briefly but repeatedly during the night.
Periodic limb movement disorder – This sleep disorder involves kicking or repeatedly twitching of the legs during sleep. This interrupts sleep. Usually, a person with this disorder is not aware of their movements and brief awakenings.
Restless legs syndrome – Individuals with syndrome have an overwhelming urge to move their legs. It can also cause unpleasant creepy, crawly sensations, in their feet, calves and thighs. Occasionally, the arms are also affected.
Physical health conditions
Many physical health conditions can cause or contribute to insomnia. These include:
- Respiratory conditions e.g. asthma, COPD (chronic obstructive pulmonary disease)
- Chronic pain
- Heart disease e.g. angina or heart failure
- Hyperthyroidism (overactive thyroid)
- Neurological conditions e.g. Parkinson’s disease and Alzheimer’s disease
- Gastroesophageal reflux disease/heartburn
- Pregnancy – particularly the third trimester
Because people tend to have more chronic health problems as they age, insomnia caused by physical health conditions is most common in older adults. The severity and duration of insomnia often varies depending on the associated health condition.
Mental health conditions
Insomnia can be caused by mental health disorders such as depression. Studies also show that insomnia can also make depression more severe. People with depression often have trouble falling asleep or staying asleep. Other mood disorders such as bipolar disorder may also cause insomnia. Other common emotional and psychological causes include anger, grief, bipolar disorder, and trauma. Treating these underlying problems is essential in resolving insomnia.
Underlying mental health problems can often affect a person’s sleeping patterns. These include:
- Anxiety disorders e.g. generalised anxiety, panic disorder or post-traumatic stress disorder
- Psychotic disorders e.g. schizophrenia
Difficulty falling asleep is common in people with anxiety disorders.
Many prescription medications and some over-the-counter medications can cause insomnia as a side effect. These include:
- Some antidepressants
- Stimulants for ADHD
- Some medications for asthma e.g. salbutamol and theophylline
- Medications for high blood pressure e.g. beta blockers
- Medications for epilepsy
- Some contraceptives
- Non-steroidal anti-inflammatory drugs (NSAIDs)
Over-the-counter medications that can cause insomnia include:
- Pain medications that contain caffeine
- Allergy medications
- Cold & flu medications
- Slimming pills
Substance use or abuse
Most kinds of substance use acutely disrupt sleep-regulatory systems in the brain, affecting the time it takes to fall asleep, the duration of sleep, and sleep quality. Despite creating feelings of relaxation and helping a person drift off to sleep, substance use prevents deep, restorative sleep cycles. Some people may find that after falling asleep with ease after using drugs or alcohol, they wake throughout the night and won’t feel refreshed after sleep ends.
Additionally, insomnia is one of the most common complaints among patients in recovery from a substance use disorder. Both continued abuse and sustained abstinence of a substance alters sleep patterns, and this change can cause some recovering users to suffer from insomnia for days or even weeks. Many experience such intense insomnia that it prompts them to relapse just so they are able to sleep. This is especially true for alcoholics and those that were addicted to benzodiazepines as they start drinking or using again because they believe that the sedative effects will help them sleep normally.
The environment where you sleep can cause insomnia. Disruptive factors such as noise, light or temperature (too high or too low), bed discomfort, and electronic distractions can interfere with sleep. Sleeping with a bed partner, who snores or has frequent visits to the bathroom, can cause sleep disruption and insomnia.
Young children can wreak havoc on their parents’ sleep, many of whom were able to sleep well before they had children. For some parents, even after their child has learned to sleep through the night, their sleep can remain impaired. During pregnancy, a woman’s sleep may be disrupted due to changes in hormones or discomfort later in her pregnancy.
Lifestyle behaviours & poor sleep habits
Activities and habits that you engage in during the day or evening can interfere with getting a good night’s sleep. These include:
- Having an irregular bedtime schedule
- Smoking or using other tobacco products
- Exercising too close to bedtime
- Drinking alcohol or beverages containing caffeine in the afternoon or evening
- Working or doing other mentally intense activities right before or after getting into bed
- Watching television in bed
- Using smart phones or other screens just before or when in bed
- Having a large evening meal too late in the evening or having spicy foods that could cause stomach trouble and heartburn
Travel or work schedule
In relation to long distance travel, jet-lag disorder comes about as a result of a temporary mismatch between the timing of the sleep and wake cycle generated by the internal circadian clock and that of the sleep and wake pattern required by a change in time zone. It takes about one day per time zone to adjust to the destination time. The symptoms of jet-lag disorder include insomnia, fatigue, malaise, poor concentration, and gastrointestinal symptoms. When flying eastwards, the sleep/wake hours are more difficult to adjust to than when flying westwards.
In relation to work schedule, when there is a mismatch between an individual’s body clock and their work schedule, shift-work disorder (also called shirt-work sleep disorder) occurs. In this disorder, shift work schedules go against internal body clocks or circadian rhythms. This causes difficulties adjusting to a different sleep/wake schedule, which results in significant issues with falling asleep, staying asleep, and sleeping when desired. Other symptoms can include difficulty concentrating, headaches, or lack of energy.
Estimates of the prevalence of chronic insomnia in adults generally vary between 10% and 15%. Estimates vary because of differing definitions and diagnostic criteria.
To be diagnosed with Chronic Insomnia (the term used by the International Classification of Sleep Disorders) a patient reports one or more of the following:
(1) Difficulty initiating sleep
(2) Difficulty maintaining sleep characterised by frequent awakenings or problems returning to sleep after awakenings.
(3) Early morning awakening with difficulty returning to sleep.
- The sleep disturbance causes clinically significant distress or impairment in social, occupational, educational, academic, behavioural, or other important areas of functioning.
- It occurs at least 3 nights a week.
- It is present for at least 3 months.
- It occurs despite adequate opportunity for sleep.
- It is not explained by and does not occur exclusively in the course of another sleep-wake disorder.
- It is not attributable to the physiological effects of illicit substances or medications.
- Coexisting medical disorders and medical conditions do not adequately explain the predominant complaint of insomnia.