Chronic Insomnia: A Practical Review

**trimurtulu** · 01-25-2009 08:43 PM

Chronic Insomnia: A Practical Review

Insomnia has numerous, often concurrent etiologies, including medical conditions, medications, psychiatric disorders and poor sleep hygiene. In the elderly, insomnia is complex and often difficult to relieve because the physiologic parameters of sleep normally change with age. In most cases, however, a practical management approach is to first consider depression, medications, or both, as potential causes. Sleep apnea also should be considered in the differential assessment. Regardless of the cause of insomnia, most patients benefit from behavioral approaches that focus on good sleep habits.

Exposure to bright light at appropriate times can help realign the circadian rhythm in patients whose sleep-wake cycle has shifted to undesirable times. Periodic limb movements during sleep are very common in the elderly and may merit treatment if the movements cause frequent arousals from sleep. When medication is deemed necessary for relief of insomnia, a low-dose sedating antidepressant or a nonbenzodiazepine anxiolytic may offer advantages over traditional sedative-hypnotics. Long-term use of long-acting benzodiazepines should, in particular, be avoided. Melatonin may be helpful when insomnia is related to shift work and jet lag; however, its use remains controversial.

Typical sleep patterns

The bed graphs show the typical sleep patterns through a night for an 18-year-old and a 75-year-old, with the pie charts showing totals for the different stages of sleep. They illustrate that as you get older you spend less time in deep (delta) sleep and more time awake.

Transient, or intermittent, insomnia lasts only a few days and is usually related to identifiable factors such as acute medical illness, changes in the sleeping environment, self-medication, jet lag and acute or recurring stress from work problems, concerns about health, marital strife, etc. In most cases, this type of insomnia can be relieved with appropriate attention to the inciting stimulus. Chronic insomnia is best defined as the subjective experience of an inadequate quantity or quality of sleep that has persisted for at least one month.

Chronic insomnia is more complex than acute transient insomnia, requiring a more directed approach to its identification, etiology and treatment. After establishing the chronicity of the complaint, a differential assessment of chronic insomnia can be made on the basis of whether the patient has difficulty staying asleep as opposed to difficulty falling asleep (Table 1). Because insomnia is essentially a symptom and not a diagnosis, it is important to try to determine the cause of chronic insomnia and not just reflexively treat the patient with sedative-hypnotic medications. It is important to remember that use of sedative-hypnotics may worsen sleep-disordered breathing such as that associated with obstructive sleep apnea.

Types of Insomnia and Possible Causes

Acute, transient insomnia (<4 weeks)

Recent or recurring stress
Change in sleeping environment
Acute illness or injury
New medications (see Table 2)
Jet lag or shift change

Chronic insomnia (>4 weeks)

Difficulty staying asleep
Medications
Drug or alcohol use
Psychiatric disorders (e.g., depression, anxiety)
Medical disorders
Sleep-disordered breathing (e.g., sleep apnea)
Nocturnal myoclonus
Difficulty falling asleep
Poor sleep hygiene
Conditioned insomnia (behavioral conditioning)
Restless legs syndrome
Circadian rhythm disorder
Advanced sleep-phase syndrome
Delayed sleep-phase syndrome

Conditions Frequently Associated with Sleep Impairment

Menopause
Gastroesophageal reflux disease
Benign prostatic hyperplasia
Incontinence
Congestive heart failure
Chronic obstructive pulmonary disease
Peptic ulcer disease
Allergic rhinitis (nasal obstruction)
Seizure disorder
Medical conditions that cause pain, such as arthritis, bursitis, fibromyalgia and reflex sympathetic dystrophy