Insomnia Insomnia

Medical and Neurological Causes 111
cations may produce insomnia (5), particularly at higher doses, especially during
the initial period of use.
Amelioration of a skin condition may require a relatively short duration of treatment,
and therefore may cause only short-term sleep disruption. The use of hypnotic
medication, especially shorter acting medications that are unlikely to produce
daytime sedation, may be ideally suited to a skin condition that has brief course
(such as poison ivy dermatitis) or intermittent exacerbation (such as eczema). Many
of the antihistamine medications used to reduce allergic response and itching are
sedating, improving sleep initiation and maintenance somewhat, but may cause
residual daytime effects on alertness and cognitive performance (6). The use of
medications such as amitriptyline or trazadone, which may improve the component
of insomnia caused by depression and pain, should be considered if duration and
severity of insomnia warrants their use, and if other medical conditions do not preclude
their use.
Problems in the nasopharynx, oropharynx, and larynx are a common cause of
sleep disruption. The most widely recognized condition that can be caused by the
pharyngeal tree is obstructive sleep apnea (OSA), which can be seen in association
with conditions such as nasal polyps, excessive submucosal oropharyngeal adipose
tissue, oropharyngeal or nasopharyngeal mass lesions, macroglossia, uvular hypertrophy,
retrognathia, and pharyngeal muscle weakness. The neck may permit OSA
to occur if it is short, broad, restricted in motion, or has anterior adipose deposition.
Mass lesions, hyoid pathology, and cervical spine degenerative changes can also
cause OSA. Sleep apnea can produce secondary insomnia through chronic disruption
of sleep continuity, and secondary insomnia in turn makes patients less tolerant
of treatment with continuous positive airway pressure (CPAP) ventilation. The
diagnostic PSG will show worsened sleep efficiency, less deep sleep, more frequent
arousal from sleep, and longer arousal when OSA is complicated by insomnia.
Upper airway resistance syndrome (UARS) may typify such a condition, where
less severely disordered breathing causes a disproportionately profound degree of
sleep disruption.
When insomnia complicates UARS and OSA, treatment with CPAP is poorly
tolerated and may require the adjunctive use of sedating medications, which will
worsen obstructive breathing to some extent. The availability of auto-titrating CPAP
and biphasic ventilation units may allow for more comfortable treatment, adjusting
the level of positive pressure required to overcome airway obstruction at any given
time. However, even the automatic changes in pressure settings may cause arousal
in a patient who suffers from insomnia. Because CPAP therapy is the most universally
effective method of treating obstructive breathing during sleep, the addition
of a medication to improve sleep initiation and continuity is a reasonable option.
Shorter acting hypnotic medications (estazolam, zaleplon, zolpidem) will least
affect the overall architecture of sleep, but will only provide benefit for the initial
hours of sleep. Re-dosing of these medications may be considered, with the caveat
that patients are more likely to awaken with a “hangover” effect that mitigates some