Dental sleep medicine series 5: General examination of a patient with sleep disordered breathing

A general and medical examination of a patient suspected of having sleep disordered breathing is essential in diagnosis. History taking and bed partner questioning can often reveal the potential causes and differential diagnoses even before physical examination and special tests. The manifestations of sleep disordered breathing will be explored in future separate posts. The next post in the series will explore the specific dental signs when screening for obstructive sleep apnoea.

Chief complaint
Insomnia
Often complain their nocturnal sleep is inadequate. Difficulty falling asleep, frequent awakening or early morning awakening with inability to fall asleep.

Excessive daytime sleepiness
Often complain of drowsiness that interferes with daytime activities and/or unavoidable napping. They may report that they need more sleep at night or there is drowsiness no matter how much sleep is had.They may report poor concentration or irritability. Children may exhibit hyperactivity rather than sleepiness.

The differential diagnosis of excessive daytime sleepiness ranges from insufcient sleep to sufcient sleep that is disrupted by pathologic events, such as apneas, or neurologic disorders, such as narcolepsy. Inquiring about sleep routines and bedtimes and wake times is essential in excluding insuffcient sleep as a cause of sleepiness. Asking patients who complain of sleepiness about other associated symptoms provides essential information. Loud snoring, gasping, snorting, and episodes of apnoea suggest the diagnosis of obstructive sleep apnoea syndrome. A history of episodic muscle weakness with buckling of the knees, laxity of the neck or jaw muscles, or complete loss of muscle tone associated with laughter, anger, or hearing or telling a joke suggests cataplexy and a diagnosis of narcolepsy. Questions assessing mood are needed to identify patients with sleep disorders associated with depression. Circadian rhythm sleep disorders should be considered in patients with complaints of nocturnal insomnia and daytime sleepiness.

Abnormal sleep behaviours
The bed partner should be the main source of information including type of behaviours and timing related to sleep onset and time of night as well as the patient's degree of responsiveness during the episodes. Episodes of inconsolable screaming and amnesia during the first third of the night suggests sleep terrors. Episodes of dream-enactment behaviour and dream recall towards the end of the sleep cycle suggest REM behaviour disorder. Epileptic seizures can occur at any time of the night and can be associated with stereotyped behaviour or dystonic posturing.

History
Usual bedtime, estimated sleep onset time, number and time of awakenings and time of final awakening. Morning symptoms including increased nasal congestion, dry mouth or morning headaches. Daytime symptoms, naps and presence of cataplexy, hypnic hallucinations, sleep paralysis and automatic behaviour.

Medication use and medical history
A wide variety of medications included non prescription and herbal supplements can affect sleep. Te history of current or past medical, surgical, and psychiatric illnesses is a source of important information. Seizure disorders, parkinsonism and dementia, arthritic conditions, asthma, ischemic heart disease, migraine or cluster headache, compressive neuropathies, and almost any painful illness can cause signifcant sleep disturbance. Anemia, renal disease, and pregnancy may cause or exacerbate restless legs syndrome or periodic limb movement disorder. Anxiety disorders, including panic disorder, and mood disorders are psychiatric disturbances that are often accompanied by insomnia, and some patients with depression complain of excessive daytime sleepiness.

Family history
A history of disordered sleep in family members is important information. Specific inquiry should be made about the existence in family members of previously diagnosed sleep disorders or symptoms suggestive of narcolepsy, obstructive sleep apnoea, periodic limb movements, enuresis, sleep terrors or sleepwalking, or insomnia. There is a strong genetic contribution to the development of narcolepsy, and genetic and familial influences sometimes have a role in the development and expression of obstructive sleep apnoea and some of the parasomnias.

Social history
Assessment of psychosocial, occupational, and academic functioning as well as of satisfaction with personal relationships can yield valuable information about the impact of disordered sleep on the patient’s life. Alcohol, caffeine, nicotine, and illicit drug use should be determined. Alcohol use or abuse may intensify snoring and obstructive sleep apnea, may be a contributor to insomnia, or may produce long-lasting changes in sleep patterns. Caffeine use produces significant sleep disturbance in susceptible persons, and nicotine dependency may lead to nocturnal awakenings.

Review of systems
Cardiovascular  and pulmonary systems are the most vital due to their relationship to ventilation and oxygenation during sleep. Angina, orthopnea, paroxysmal nocturnal dyspnea, and wheezing may indicate that sleep disturbance is due to cardiac or pulmonary disease. Heartburn and reflux of gastric contents into the throat when the patient is recumbent may cause nocturnal choking episodes. Leg cramps and neuropathic pain may be accompanied by sleep disruption. Nocturia is a common cause of disturbed sleep, particularly in older men. Depression or anxiety can contribute to insomnia.

Physical examination
Examination of the head and neck is particularly important in patients with suspected obstructive sleep apnea. Auscultation of the chest may reveal expiratory wheezes in patients with nocturnal asthma attacks. Thoracic abnormalities such as kyphoscoliosis may compromise ventilatory capacity, leading to hypoventilation and nocturnal breathing difficulties. Auscultation may reveal a prominent fourth heart sound originating from the enlarged right ventricle and murmurs related to pulmonary or tricuspid valve insufficiency. On abdominal examination, hepatomegaly may suggest that alcohol abuse is contributing to sleep disturbance or, in conjunction with other findings, that congestive heart failure is a factor. Examination of the extremities may reveal joint swelling or deformity, decreased range of motion across affected joints, and thickening of synovial tissue in patients with disordered sleep due to arthritis.

Findings on mental status testing and neurologic examination may indicate the presence of a psychiatric or neurologic disease that causes or contributes to disturbed sleep. Impairment of short-term memory, judgment, language functions, and abstract reasoning suggests the presence of a dementing illness that may cause insomnia or nocturnal confusion. Assessment of mood may suggest the presence of mania or depression, either of which may be associated with insomnia. Delusional thoughts and agitation may indicate that acute psychosis is the cause of insomnia. Reduced alertness with slurred speech and nystagmus may be signs of hypnotic or sedative abuse. Impaired sensation and reduced or absent tendon reflexes may indicate peripheral neuropathy, sometimes accompanied by nocturnal paresthesias or burning pain.