Short-Term Insomnia

Etiology

The cause of short-term insomnia is not fully understood and cannot be attributed to a single factor. Instead, its etiology involves a combination of environmental, genetic, psychological, and behavioral factors that contribute to a state of hyperarousal.[3]

Epidemiology

Approximately one-third of the global population reports dissatisfaction with their sleep. Sleep disturbances and insomnia affect up to 50% of older adults. According to DSM-5-TR criteria, 4% to 22% of adults meet the diagnostic criteria for insomnia. Women are twice as likely to experience insomnia as age-matched men, and the prevalence of insomnia increases with menopause.[3][4]

Pathophysiology

The exact mechanism of short-term insomnia remains unknown, although several models have been proposed. An emerging consensus suggests that short-term insomnia is a disorder of hyperarousal. Hyperarousal refers to an increased state of somatic, cortical, and cognitive activation. Patients with short-term insomnia exhibit elevated levels of cortisol, body temperature, 24-hour metabolic rate, and heart rate.[5] 

There is growing evidence linking short-term insomnia to the upregulation of wake-promoting chemicals, including orexin (hypocretin), histamine, and catecholamines. These wake-promoting chemicals are associated with the downregulation of sleep-promoting substances, including adenosine, serotonin, melatonin, and gamma-aminobutyric acid (GABA). Further research is needed to understand the precise molecular mechanisms underlying hyperarousal better.[6]

History and Physical

Patients with short-term insomnia typically present with a constellation of symptoms and concerns related to the quantity or quality of their sleep. Common symptoms include difficulty initiating or maintaining sleep, early morning awakenings, and trouble falling back asleep. Notably, these symptoms occur despite the patient having an adequate opportunity to sleep. Evaluation should include a comprehensive medical and psychiatric history. Maintaining a sleep diary for over 2 to 4 weeks can help assess sleep patterns and identify contributing factors to sleep disturbances.[7]

Another important aspect of the patient’s history is identifying how nighttime sleep disturbances contribute to daytime impairments, which may include:

• Reduced functioning or productivity at work or school
• Fatigue or low energy
• Frequent daytime napping
• Difficulty concentrating
• Increased risk of errors and accidents
• Impaired attention, concentration, or memory
• Mood disturbances or irritability
• Impaired interpersonal or social relationships
• A general sense of poor quality of life

Evaluators should also rule out other sleep-related disorders, such as obstructive sleep apnea, narcolepsy, or restless legs syndrome.[7] Recent research suggests that insomnia may independently contribute to the development of major depression, with patients often presenting with a depressed mood and complaints of anhedonia.[8]

Evaluation

The evaluation of insomnia primarily relies on obtaining a thorough sleep history, as the diagnosis is made clinically. Ruling out other potential causes of insomnia, including medication, substance use, medical conditions, or mental health disorders, is crucial. Polysomnography has a limited role but can help differentiate sleep apnea and other sleep disorders from short-term insomnia. Sleep diaries and logs are essential tools in diagnosing short-term insomnia. Patients are typically asked to track their sleep patterns, including time in bed, nighttime awakenings, sleep satisfaction, sleep onset latency, and total sleep time. These data, usually collected over 2 to 4 weeks, are then reviewed by the clinician.[7] 

The 2 primary classification systems for insomnia disorders are the ICSD-3 and DSM-5-TR. The ICSD-3 categorizes insomnia into 3 types—chronic insomnia disorder, short-term insomnia disorder, and other insomnia disorders.[9] In contrast, the DSM-5-TR criteria uses a descriptive approach, classifying insomnia based on the frequency and duration of symptoms.[7] 

Questionnaires such as the Insomnia Severity Index (ISI) and the Pittsburgh Sleep Quality Index (PSQI) are valuable tools for aiding in the diagnosis of insomnia. The ISI consists of 7 questions, each scored on a scale from 0 to 4, with a maximum total score of 28. Higher scores indicate greater severity of insomnia, and a score above 14 indicates clinically significant insomnia. The questionnaire can be self-administered by patients and reviewed by the provider during evaluation. The PSQI is designed to help differentiate among various sleep-related disorders. The PSQI comprises 19 questions that assess multiple domains of sleep, including quality, latency, duration, efficiency, use of sleep medication, daytime dysfunction, and sleep disturbances, over a 1-month period.[10]

Currently, 2 primary modalities are used to measure sleep activity—actigraphy and polysomnography. Actigraphy is a technique that involves the use of devices worn on the wrists or ankles to measure limb movement. The collected data provide patterns of wakefulness and sleep, allowing for the calculation of general sleep parameters such as sleep latency, sleep efficiency, total sleep time, and wakefulness after sleep onset. While these parameters are useful in evaluating insomnia, actigraphy cannot assess rapid eye movement (REM) and non-REM sleep cycles, which require polysomnography for accurate measurement.[11] 

Although polysomnography is the gold standard for diagnosing sleep-related disorders, it should not be used routinely for the evaluation of insomnia. This technique is primarily indicated when there is a clinical suspicion of an underlying sleep disorder. Such conditions include breathing disorders, such as obstructive sleep apnea and central sleep apnea, as well as sleep-related movement disorders, including periodic limb movement disorder.[12]

Treatment / Management

Non-pharmacological treatment is the first-line recommendation for managing short-term insomnia. These methods include cognitive therapies, sleep restriction, stimulus control, and education on sleep hygiene.[3][13][14](B3)

Cognitive Therapies

These therapies help patients identify and connect their thoughts and attitudes—such as excessive worry, emotional distress, and dysfunctional thinking—to the development of short-term insomnia. The goal is to replace unhelpful beliefs, like overestimating the number of hours needed to feel rested, anxiety about missing sleep, and concerns about the impact of insomnia on daytime functioning, with more positive and reassuring thoughts and attitudes.

Sleep Restriction Therapy

This therapy limits the amount of time spent in bed to the actual total sleep time, as determined from sleep logs or diaries, which is typically less than the patient’s usual sleep duration. This approach enhances the sleep drive, induces sleep inertia, and improves sleep efficiency by reducing early-morning awakenings and sleep onset latency. Sleep restriction should not be reduced to less than 5 to 6 hours per night.[15](A1)

Stimulus Control Therapy

This therapy encourages patients to associate the bed exclusively with sleep. Time spent in bed should be reserved for sleep and sexual activity only. To implement this approach, patients should go to bed only when they feel sleepy. They should also avoid staying in bed for more than 15 minutes if they are unable to sleep and establish consistent wake and sleep times.

Sleep Hygiene Education

This education helps patients recognize that certain behaviors can contribute to sleep problems. Patients are encouraged to limit their caffeine intake during the day and reduce daytime napping. Additionally, they should avoid eating, engaging in vigorous exercise, consuming alcohol, and using tobacco products before bedtime.

Additional Therapies

Other non-pharmacological therapies include exercise, mindfulness meditation, mantra meditation, and meditative movements such as yoga and tai chi. Combining exercise with meditation has been shown to improve sleep quality.[16](A1)

• Exercise, particularly among individuals aged 65 and older, enhances sleep quality and efficiency. Resistance training and walking have been found to be particularly beneficial for improving sleep quality in this age group.[17]
• Incorporating mantra meditation with cognitive-behavioral therapy can further improve sleep outcomes.
• Mindfulness-based interventions and meditation address negative cognitive and behavioral patterns, helping to alleviate insomnia.[18] 
• Acupuncture has been shown to improve sleep efficiency, increase total sleep time, and reduce wake-up times.[19]
(A1)

The 2017 American Academy of Sleep Medicine Clinical Practice Guideline for the Pharmacologic Treatment of Chronic Insomnia in Adults [20] highlights that pharmacological recommendations are generally weak, with moderate-to-low quality evidence. However, the guideline recommends the treatments listed below.(A1)

• Treatment for sleep onset insomnia: Eszopiclone at strengths of 2 mg or 3 mg at bedtime; ramelteon 8 mg at bedtime; temazepam 15 mg at bedtime; triazolam 0.25 mg at bedtime; zaleplon 5 mg or 10 mg at bedtime; or zolpidem 10 mg at bedtime.
• Treatment for sleep maintenance insomnia: Doxepin at strengths 3 mg or 6 mg at bedtime; eszopiclone 2 mg or 3 mg at bedtime; temazepam 15 mg at bedtime; suvorexant 10 mg or 15/20 mg or 20 mg at bedtime; or zolpidem 10 mg at bedtime.

According to the European Insomnia Guideline,[21] there is insufficient evidence to support the use of antihistamines, antipsychotics, fast-release melatonin, or herbal remedies for treating insomnia, and these treatments may have potential disadvantages.

If a medication is ineffective or has an adverse effect profile that does not align with a patient’s lifestyle or physiology, clinicians can switch to an alternative option. Clinicians are also encouraged to review the adverse effect profiles and drug interactions of each medication. Notably, all prescription drugs carry the risk of adverse effects, including addiction, withdrawal, and tolerance, and should be used for short durations.[20][22][23](A1)

In older populations, it is essential to consider the Beers Criteria for safe and appropriate prescribing. Medications to avoid include benzodiazepines, antihistamines, and tricyclic antidepressants, as well as other potentially harmful drugs.

Differential Diagnosis

The following conditions should be ruled out before confirming a diagnosis of short-term insomnia:

• Insomnia disorder due to substance or medication use
• Insomnia related to medical conditions, including pain or psychiatric disorders
• Obstructive sleep apnea or central sleep apnea
• Restless leg syndrome
• Narcolepsy
• Sleepwalking or sleep terrors
• Depression and anxiety disorders
• Circadian rhythm sleep-wake disorders, such as delayed sleep phase disorder
• Shift work sleep disorder

Prognosis

Sleep is crucial for maintaining overall health and promoting a sense of well-being. Emerging evidence links sleep disturbances and insomnia disorders to increased cardiometabolic morbidity and mortality. The hyperarousal state associated with insomnia contributes to a higher incidence of hypertension, type 2 diabetes, and acute myocardial infarction. These conditions are largely attributed to the effects of chronic stress and elevated cortisol levels (hypercortisolemia) seen in individuals with insomnia.

Other studies have shown a correlation between insomnia and neurocognitive decline, including impairments in memory, executive functioning, and attention. These cognitive deficits may increase the risk of developing psychiatric conditions such as depression, anxiety, and even suicidality. However, the long-term prognosis of short-term insomnia is generally favorable when appropriate interventions and treatments are implemented promptly.[24]

Complications

Untreated and unrecognized short-term insomnia can lead to a range of complications. Clinicians should be aware of the following potential consequences:

• Dependence on sleep medications
• Development of psychiatric disorders, including anxiety and depression
• Increased risk of cardiovascular disease
• Hypertension
• Type 2 diabetes [24][25]