Middle-of-the-night insomnia

Middle-of-the-night insomnia (MOTN) is characterized by having difficulty returning to sleep after waking up during the night or very early in the morning. This kind of insomnia (sleeplessness) is different from initial or sleep-onset insomnia, which consists of having difficulty falling asleep at the beginning of sleep.

Middle-of-the-night insomnia
Other names	Nocturnal awakenings, Middle of the night awakenings, Sleep maintenance insomnia, and Middle insomnia.
Specialty	Sleep medicine

The disrupted sleep patterns caused by middle-of-the-night insomnia make many sufferers of the condition complain of fatigue the following day. Excessive daytime sleepiness is reported nearly two times higher by individuals with nocturnal awakenings than by people who sleep through the night.[1]

Sleep research conducted in the 1990s showed that such waking up during the night may be a natural sleep pattern, rather than a form of insomnia.[2] If interrupted sleep (called "biphasic sleeping" or "bimodal sleep") is perceived as normal and not referred to as "insomnia", less distress is caused and a return to sleep usually occurs after about one hour.[3]

Causes

• Pain
• Pregnancy
• Anxiety
• Difficulty breathing / sleep apnea
• Need to use the bathroom
• Hunger or thirst
• Illness
• Shift work
• Erratic sleep schedule[4]

Nocturnal awakenings are more common in older patients and have been associated with depressive disorders, chronic pain, obstructive sleep apnea, obesity, alcohol consumption, hypertension, gastroesophageal reflux disease, heart disease, menopause, prostate problems, and bipolar disorders.[4] Gastro-intestinal discomfort arising from food that has not been fully cooked, is also a contributor to middle of the night insomnia. Nocturnal awakenings can be mistaken as shift work disorder.

Treatment

Middle-of-the-night insomnia is often treated with medication, although currently Intermezzo (zolpidem tartrate sublingual tablets) is the only Food and Drug Administration-approved medication specifically for treating MOTN awakening.[5] Because most medications usually require 6–8 hours of sleep to avoid lingering effects the next day, these are often used every night at bedtime to prevent awakenings.[6] Medication may not be prescribed in some cases, especially if the cause turns out to be the patient ingesting too much fluid during the day or just before they go to sleep.

Sleep restriction therapy and stimulus control therapy as described in insomnia have shown significance in treating middle of night insomnia. Some studies have shown that zaleplon, which has a short elimination half-life, may be suitable for middle-of-the-night administration because it does not impair next day performance.[7][8][9]

Prevalence

Waking up in the middle of the night, or nocturnal awakening, is the most frequently reported insomnia symptom, with approximately 35% of Americans over 18 reporting waking up three or more times per week.[1] Of those who experience nocturnal awakenings, 43% report difficulty in resuming sleep after waking, while over 90% report the condition persisting for more than six months. Greater than 50% contend with MOTN conditions for more than five years.

A 2008 "Sleep in America" poll conducted by the National Sleep Foundation found that 42% of respondents awakened during the night at least a few nights a week, and 29% said they woke up too early and couldn’t get back to sleep.[10] Other clinical studies have reported between 25% and 35% of people experience nocturnal awakenings at least three nights a week.[11]

See also

• Biphasic and polyphasic sleep

References

1. Ohayon MM (2008). "Nocturnal awakenings and comorbid disorders in the American general population". Journal of Psychiatric Research. 43 (1): 48–54. doi:10.1016/j.jpsychires.2008.02.001. PMID 18374943.
2. Wolchover, Natalie. "Busting the 8-Hour Sleep Myth: Why You Should Wake Up in the Night". Live Science. Retrieved 27 May 2011.
3. Hegarty, Stephanie (2012-02-22). "The myth of the eight-hour sleep". BBC News.
4. ""Daytime pharmacodynamic and pharmacokinetic evaluation of low-dose sublingual transmucosal zolpidem hemitartrate"- Human Psychopharmacology: Clinical and Experimental, 2008;23(1):13-20, Thomas Roth, David Mayleben, Bruce C. Corser, Nikhilesh N. Singh". Retrieved 2008-05-27.
5. "FDA approves first insomnia drug for middle-of-the-night waking followed by difficulty returning to sleep". Food and Drug Administration. 2012-11-23. Retrieved 2012-11-27.
6. ""Nocturnal awakenings: a case study with decision points"- Journal of Family Practice, April 2008" (PDF). Archived from the original (PDF) on 2010-07-14. Retrieved 2008-07-11.
7. Zammit GK, Corser B, Doghramji K, et al. (October 2006). "Sleep and residual sedation after administration of zaleplon, zolpidem, and placebo during experimental middle-of-the-night awakening". J Clin Sleep Med. 2 (4): 417–23. PMID 17557470.
8. Verster JC, Veldhuijzen DS, Patat A, Olivier B, Volkerts ER (January 2006). "Hypnotics and driving safety: meta-analyses of randomized controlled trials applying the on-the-road driving test". Curr Drug Saf. 1 (1): 63–71. doi:10.2174/157488606775252674. hdl:1874/19756. PMID 18690916.
9. Stone BM, Turner C, Mills SL, et al. (February 2002). "Noise-induced sleep maintenance insomnia: hypnotic and residual effects of zaleplon". Br J Clin Pharmacol. 53 (2): 196–202. doi:10.1046/j.-5251.2001.01520.x. PMC 1874295. PMID 11851645.
10. "2008 "Sleep in America" poll". Archived from the original on 2008-07-03. Retrieved 2008-07-10.
11. Maurice M. Ohayon, MD, DSc, PhD (2002). "Epidemiology of Insomnia: What We Know and What We Still Need to Learn". Sleep Medicine Reviews. 6 (2): 97–111. doi:10.1053/smrv.2002.0186. PMID 12531146.CS1 maint: multiple names: authors list (link)