National Sleep Foundation

Chapter 2: Insomnia

Risk Factors

At least five conditions can lead to insomnia:

  1. Learning and conditioning factors;
  2. Maladaptive thoughts about sleep and perceived lack of self-efficacy in managing insomnia (i.e., cognitive factors);
  3. Medical disorders and medications that impair the sleep-wake cycle;
  4. Poor sleep habits and other maladaptive behaviors; and
  5. Psychological issues (e.g., stress vulnerability and hyperarousal) and psychiatric conditions.

In addition, certain types of people are at higher risk for experiencing insomnia, including:

  • Women: Women are at a higher risk for insomnia than men.1, 2 This may be due to hormones occurring during puberty,3  pregnancy4, 5, 6 the postpartum period,or during the menopausal transition and after menopause.
  • Individuals with other medical conditions: Patients with medical or mental health conditions are at increased risk of insomnia.8, 9 As noted, these include psychiatric disorders such as depression, substance abuse, or anxiety;10, 11, 12, 13, 14 and medical conditions such as cardiopulmonary disease, musculoskeletal conditions, gastrointestinal disease, endocrine conditions, chronic renal failure, and neurological disease;15, 16
  • Older individuals: The elderly have a higher risk for insomnia due to lifestyle changes associated with retirement, increased health problems, and increased use of medications.17, 18, 19 Elderly individual’s circadian rhythms also tend to phase shift earlier, which may interfere with their desired sleep time. In general, older individuals have less deep sleep, more sleep fragmentation, and use a large number of medications, all of which may predispose them to insomnia.
  • Behaviors: Certain behaviors, such as poor sleep habits and engaging in shift work, increase a person’s risk of experiencing insomnia, including having poor sleep habits and engaging in shift work.20

It is important to note that cause and effect may be circular: risk factors that induce or worsen insomnia may also be consequences of insomnia.


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