9.2 Sleep Concerns: Insomnia

The most common sleep complaint is insomnia; though the prevalence of insomnia varies by severity, researchers estimate that around 10% of the population experiences insomnia (Mai & Buysse, 2008). It is most often, but not always, secondary to some other underlying cause, which may be situational, physical, or psychological in nature.

Insomnia is defined by how someone feels the day after having trouble falling or staying asleep or waking unusually early in the morning—unrefreshed and unrested. It often causes excessive sleepiness, fatigue, a lack of energy, difficulty concentrating, depressed mood, and irritability. Insomnia is a real disorder that can negatively impact one’s overall health and wellbeing.

Cases of insomnia are generally categorized in one of the following four ways:

• Sleep-onset insomnia is difficulty falling asleep.
• Sleep-maintenance insomnia is difficulty staying asleep.
• Early-morning awakening is waking up early and not being able to go back to sleep.
• Mixed insomnia is any combination of these three categories.

In addition, insomnia is broken down into three categories based on longevity of symptoms:

• Transient insomnia involves isolated cases that last for a few weeks or less.
• Intermittent insomnia is defined as recurring transient insomnia.
• Chronic insomnia occurs at least three nights per week for more than a month.

Causes and Risk Factors for Insomnia

Transient insomnia is common and generally brought on by stressful situations such as work, family pressures, or a traumatic event. Being in a new environment or otherwise experiencing a change in your normal routine are examples of situational risk factors for insomnia. Poor sleep conditions—bright lights or loud noises, for example—also represent situational risks. Jobs or school might also be risk factors.

Psychological risk factors for insomnia include stress, anxiety, depression, and other psychiatric disorders. Being sick or in pain and having medical conditions or physical disorders, such as asthma or arthritis, are physical risk factors for insomnia, as are the use of some medications, caffeine, alcohol, or other drugs. Sex and age also impact the risk of insomnia; women are more likely to have trouble sleeping, as are older people (Kalmbach et al., 2018). Hormone fluctuations—for example, those experienced during menopause—are yet another physical risk factor for insomnia.

A relatively small percentage of people who suffer from insomnia don’t appear to have any associated situational, psychological, or physical risk factors. Rather, they experience a constant state of hyperarousal, which may be genetic (Kalmbach et al., 2018).