Insomnia occurs when an individual has trouble falling asleep or staying asleep even though there is opportunity to get a full night of sleep. Because different people need different amounts of sleep, insomnia is therefore the inability to get the amount of sleep we need to wake up feeling well rested and refreshed. Insomnia is defined by the quality of sleep and how we feel after sleeping not necessarily the number of hours we sleep at night or how quickly we doze off at the beginning of the night. Even if we are spending 7 to 9 hours a night in bed, if we feel drowsy and fatigued during the day, we may be having insomnia.

Insomnia is the most common sleep complaint. Roughly 10 to 30% of adults have insomnia at any given point in time and up to half of people have insomnia in a given year. About 6% of people have insomnia that is not due to another problem and lasts for more than a month. People over the age of 65 are affected more often than younger people. Females are more often affected than males. Insomnia is 40% more common in women than in men.

Insomnia includes a wide range of sleeping disorders, from lack of quality of sleep to lack of quantity of sleep. It may also include: difficulty falling asleep, difficulty staying asleep throughout the night and waking up too early in the morning. Insomnia involves both a sleep disturbance and daytime symptoms.

Classes of Insomnia

Insomnia can be classified on the basis of duration of the problem. It is classified as transient, acute, or chronic.

a). Transient insomnia:   Lasts for less than a week. It can be caused by another disorder, by changes in the sleep environment, by the timing of sleep, severe depression, or by stress. Its consequences which include sleepiness and impaired psychomotor performance are similar to those of sleep deprivation.

b). Acute insomnia:   Is the inability to consistently sleep well for a period of less than a month. Insomnia is present when there is difficulty initiating or maintaining sleep or when the sleep that is obtained is non-refreshing or of poor quality. These problems occur despite adequate opportunity and circumstances for sleep and they must result in problems with daytime function. Acute insomnia is also known as short term insomnia or stress related insomnia.

c). Chronic insomnia:   Lasts for longer than a month. It can be caused by another disorder, or it can be a primary disorder. People with high levels of stress hormones or shifts in the levels of cytokines are more likely than others to have chronic insomnia. Its effects can vary according to its causes. They might include muscular weariness, hallucinations, and/or mental fatigue. Chronic insomnia can cause double vision.

Insomnia may be the primary problem, or it may be associated with other conditions. Insomnia can be caused by physical factors as well as psychological factors. There is often an underlying medical condition that causes chronic insomnia, while transient insomnia may be due to a recent event or occurrence.

Common causes of insomnia

a). Electronic Devices:   Electronic devices with self-luminous "backlit" displays can affect evening melatonin, which might result in delayed sleep.

b). Disruptions in circadian rhythm:   Jet lag, job shift changes, high altitudes, noisiness, hotness or coldness.

c). Psychological issues:   People with mood disorders, such as bipolar disorder or depression, as well as anxiety disorders or psychotic disorders are more likely to have insomnia.

d). Medical conditions:   Brain lesions and tumors, stroke, chronic pain, chronic fatigue syndrome, congestive heart failure, angina, chronic obstructive pulmonary disease, asthma, sleep apnea, Parkinson's and Alzheimer's diseases, hyperthyroidism, arthritis, Nasal/sinus allergies, Gastrointestinal problems such as reflux, etc.

e). Hormones:   Estrogen, hormone shifts during menstruation. Lower level of Cortisol is linked to insomnia.

f). Other factors:   Sleeping next to a snoring partner, parasites, genetic conditions, overactive mind, and pregnancy.

Common causes of chronic insomnia include:

Chronic insomnia is usually a result of stress, life events or habits that disrupt sleep. Treating the underlying cause can resolve the insomnia, but sometimes it can last for years. Common causes of chronic insomnia include:

a). Stres:   Concerns about work, school, health, finances or family can keep the mind active at night, making it difficult to sleep. Stressful life events or trauma such as the death or illness of a loved one, divorce, or a job loss also may lead to insomnia.

b). Travel or work schedule:   The circadian rhythms act as an internal clock, guiding such things as sleep-wake cycle, metabolism and body temperature. Disrupting the patient’s body's circadian rhythms can lead to insomnia. Causes include jet lag from traveling across multiple time zones, working a late or early shift, or frequently changing shifts.

c). Eating too much late in the evening:   Having a light snack before bedtime is not bad, but eating too much may cause someone to feel physically uncomfortable while lying down. Many people also experience heartburn, a backflow of acid and food from the stomach into the oesophagus after eating, which may keep the patient awake.

d). Mental health disorders:   Anxiety disorders, such as posttraumatic stress disorder, may disrupt asleep. Awakening too early can be a sign of depression. Insomnia often occurs with other mental health disorders as well.

e). Medications:   Many prescription drugs can interfere with sleep, such as certain antidepressants and medications for asthma or blood pressure. Many over-the-counter medications such as some pain medications, allergy and cold medications, and weight-loss products contain caffeine and other stimulants that can disrupt sleep.

f). Sleep-related disorders:   Sleep apnoea causes patient to stop breathing periodically throughout the night, interrupting his sleep. Restless legs syndrome causes unpleasant sensations in legs and an almost irresistible desire to move them, which may prevent the patient from falling asleep.

g). Caffeine, nicotine and alcohol:   Coffee, tea, cola and other caffeinated drinks are stimulants. Drinking them in the late afternoon or evening can keep from falling asleep at night. Nicotine in tobacco products is another stimulant that can interfere with sleep. Alcohol may help fall asleep, but it prevents deeper stages of sleep and often causes awakening in the middle of the night.

Sleep-onset insomnia:

Sleep-onset insomnia is difficulty falling asleep at the beginning of the night. Delayed sleep phase disorder can be misdiagnosed as insomnia, as sleep onset is delayed too much later than normal while awakening spills over into daylight hours. It is common for patients who have difficulty falling asleep to also have nocturnal awakenings with difficulty returning to sleep. Two thirds of these patients wake up in the middle of the night, with more than half having trouble falling back to sleep after a middle-of-the-night awakening. Early morning awakening is an awakening occurring earlier (more than 30 minutes) than desired with an inability to go back to sleep, and before total sleep time reaches 6.5 hours. Early morning awakening is often a characteristic of depression.

Symptoms of insomnia:

  • Difficulty falling asleep at night
  • Trouble getting back to sleep after waking up
  • Waking up too early in the morning
  • Not feeling well-rested after a night's sleep
  • Daytime downiness, fatigue, tiredness or sleepiness
  • Irritability, depression or anxiety
  • Difficulty paying attention, focusing on tasks or remembering
  • Increased errors or accidents
  • On-going worries about sleep
  • Relying on sleeping pills or alcohol to fall asleep

Diagnosing insomnia

Doctors use a number of approaches to diagnose insomnia and understand a person's unique symptoms. Some of these measures can be done at home, while others require an office visit or an appointment at a sleep clinic.

There is no definite test for insomnia. Doctors use many different tools to diagnose and measure insomnia symptoms, some of which involve asking the questions in the office, having fill out logs and questionnaires, performing certain blood tests, or doing an overnight sleep study. All of these tests help the therapist understand the patient’s personal experience with insomnia and create the right treatment plan.

a). Sleep log:   A sleep log is a simple diary that keeps track of details about sleep. In a sleep log, record details like bedtime, wake up time, how sleepy one feels at various times during the day, and more. A sleep log can also help the doctor figure out what might be causing insomnia.

b). Sleep inventory:   A sleep inventory is an extensive questionnaire that gathers information about personal health, medical history, and sleep patterns.

c). Blood tests:   Doctor may perform certain blood tests to rule out medical conditions such as thyroid problems, which can disrupt sleep in some people.

d). Sleep study:   Doctor may suggest to do an overnight sleep study, or polysomnography, to gather information about the night time sleep. In this exam, one sleeps overnight in a lab set up with a comfortable bed. During the exam the patient will be connected to an EEG, which monitors the stages of sleep. A sleep study also measures things like oxygen levels, body movements, and heart and breathing patterns. A sleep study is a non-invasive test.

Risk of insomnia is greater if:

a). You are a woman:   Hormonal shifts during the menstrual cycle and in menopause may play a role. During menopause, night sweats and hot flashes often disrupt sleep. Insomnia is also common with pregnancy.

b). You are over age 60:   Because of changes in sleep patterns and health, insomnia increases with age.

c). You have a mental health disorder or physical health condition:   Many issues that impact your mental or physical health can disrupt sleep.

d). You're under a lot of stress:   Stressful times and events can cause temporary insomnia and major or long-lasting stress can lead to chronic insomnia.

e). You don't have a regular schedule:   Changing shifts at work or traveling can disrupt your sleep-wake cycle.

Complications of insomnia:

Sleep is as important to health as a healthy diet and regular physical activity. Whatever is reason for sleep loss, insomnia can affect both mentally and physically. People with insomnia report a lower quality of life compared with people who are sleeping well. Complications of insomnia may include:

1.   Lower performance on the job or at school

2.   Slowed reaction time while driving and a higher risk of accidents

3.   Mental health disorders, such as depression, anxiety disorder or substance abuse

4.   Reduced immune system

5.   Increased risk and severity of long-term diseases or conditions, such as high blood pressure, diabetes and heart disease.