(HealthDay News) -- Insomnia is the general term used to mean waking too early, or having difficulty falling asleep or staying asleep.

The National Heart, Lung and Blood Institute says many factors can lead to insomnia, including:

  • Headache or arthritis.
  • Heart failure or asthma.
  • Hyperthyroidism, the term for an overactive thyroid.
  • Heartburn.
  • Menopause and associated hot flashes.
  • Other sleep disorders, including sleep-related breathing problems or restless legs syndrome.