失眠

本條目介紹的是睡眠障礙。關於失眠的其他意思，請見「失眠 (消歧義)」。

失眠
播放媒體
影片介紹
發音	ㄕ ㄇ一ㄢˊ
醫學專科	精神病學、睡眠醫學
症狀	難以入睡、白天想睡覺、沒精神、應激性、抑鬱
併發症	車禍
肇因	未知、心理壓力、慢性疼痛、心臟衰竭、甲狀腺功能亢進症、胃灼熱、不寧腿綜合徵
診斷方法	根據症狀、睡眠檢測
相似疾病或共病	睡眠相位後移症候群、不寧腿綜合徵、睡眠呼吸暫停、精神疾病、睡眠障礙
治療	睡眠衛教、認知行為療法、安眠藥
盛行率	0~20%

失眠是一種不容易自然地進入睡眠狀態的睡眠障礙。可能是很難睡著，或是很難維持較長時間的睡眠。失眠一般會伴隨著白天精神不佳、想睡覺、易怒、或是抑鬱等症狀。失眠可能會增加車禍的風險，也可能會讓人無法專注及學習。失眠可能是短期的，持續幾天到一週，也可能是長期的，持續一個月以上。

失眠可能和其他的藥物或症狀無關，也有可能是受到其他藥物、症狀或疾病的影響。會導致失眠的症狀有心理壓力、慢性疼痛、心臟衰竭、甲狀腺功能亢進症、胃灼熱、不寧腿綜合徵、更年期，也有可能是因為咖啡因、尼古丁及酒精的影響，其他風險因子有夜班及睡眠呼吸暫停。失眠診斷會根據睡眠習慣為基礎，也會進行身體檢查，以確認是否有其他潛藏造成失眠的病症，也可能會進行睡眠檢測來找出失失眠的原因。

一般而言，會以睡眠衛教及生活習慣的調整作為第一線的治療方式。睡眠衛教包括充足的睡眠時間、白天時曬太陽、安靜及暗的臥室以及規律的運動，可以再配合認知行為療法。安眠藥可能會有幫助，不過有些受傷、失智症及成癮的症狀和安眠藥使用有關。若使用藥物治療，一般不建議使用超過四週到五週。還不清楚替代療法在治療失眠的效果及安全性。

類型

DSM-5 診斷標準

精神疾病診斷與統計手冊第五版（DSM-5）中寫到，失眠的診斷標準如下：

病患主訴中提到對於睡眠時間長度和睡眠品質的不滿與下列至少一項敘述有關：

• 難以入睡。（小孩的失眠表現則為：如果照顧者沒有哄小孩睡覺，小孩就會難以入睡）

一些未翻譯的非現代漢語已進行隱藏，歡迎參與翻譯。

• Difficulty maintaining sleep, characterized by frequent awakenings or problems returning to sleep after awakenings. (In children, this may manifest as difficulty returning to sleep without caregiver intervention.)
• Early-morning awakening with inability to return to sleep.

In addition,

• The sleep disturbance causes clinically significant distress or impairment in social, occupational, educational, academic, behavioral, or other important areas of functioning.
• The sleep difficulty occurs at least 3 nights per week.
• The sleep difficulty is present for at least 3 months.
• The sleep difficulty occurs despite adequate opportunity for sleep.
• The insomnia is not better explained by and does not occur exclusively during the course of another sleep-wake disorder (e.g., narcolepsy, a breathing-related sleep disorder, a circadian rhythm sleep-wake disorder, a parasomnia).
• The insomnia is not attributable to the physiological effects of a substance (e.g., a drug of abuse, a medication).
• Coexisting mental disorders and medical conditions do not adequately explain the predominant complaint of insomnia.

Types

Insomnia can be classified as transient, acute, or chronic.

1. 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 – sleepiness and impaired psychomotor performance – are similar to those of sleep deprivation.
2. 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.
3. 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.

Patterns

Symptoms of insomnia:

• difficulty falling asleep, including difficulty finding a comfortable sleeping position
• waking during the night and being unable to return to sleep
• feeling unrefreshed upon waking
• daytime sleepiness, irritability or anxiety

Sleep-onset insomnia is difficulty falling asleep at the beginning of the night, often a symptom of anxiety disorders. Delayed sleep phase disorder can be misdiagnosed as insomnia, as sleep onset is delayed to 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.

Poor sleep quality

Poor sleep quality can occur as a result of, for example, restless legs, sleep apnea or major depression. Poor sleep quality is caused by the individual not reaching stage 3 or delta sleep which has restorative properties.

Major depression leads to alterations in the function of the hypothalamic-pituitary-adrenal axis, causing excessive release of cortisol which can lead to poor sleep quality.

Nocturnal polyuria, excessive nighttime urination, can be very disturbing to sleep.

Subjectivity

Some cases of insomnia are not really insomnia in the traditional sense. People experiencing sleep state misperception often sleep for normal durations, yet overestimate the time taken to fall and remain asleep.

參見

• 維他命
• 睡眠
• 時間生物學
• 睡眠學習
• 注意力不足過動症#充足的睡眠