205Physical Examination
Examination may be normal, or may reveal obesity, a narrow oropharynx, or a large
neck circumference, but no particular features on physical examination are suffi-
cient to rule in or exclude the possibility of OSA.
Diagnostic Evaluation for OSA
Testing options for OSA include traditional laboratory polysomnography and out-
of- center sleep testing (also referred to as ambulatory or OCST or home sleep apnea
testing) [ 49 ]. While laboratory testing remains the “gold standard,” OCST is an
acceptable initial option for patients in whom there is a strong clinical suspicion of
OSA. For many patients, OCST has the added benefits of convenience and improved
tolerability, allowing patients to sleep in their habitual environment. It should be
noted, however, that OCST often underestimates the frequency of respiratory events
because recording time, rather than sleep time, is used as the denominator for the
AHI [ 50 ]. Furthermore, OCST is intended only to evaluate for the presence of sleep-
disordered breathing and should not be ordered if other sleep disorders including
narcolepsy or periodic limb movements are suspected. Patients with comorbidities
that increase the risk of additional or alternative sleep-related breathing disorders
such as hypoventilation or central sleep apnea should also undergo laboratory test-
ing rather than OCST. Nocturnal oximetry is not considered an adequate screening
tool as it has poor sensitivity for detection of OSA.
Treatment Options for OSA
The goal of treating OSA is to reduce or ideally eliminate apneas, hypopneas, and
oxygen desaturation during sleep and thereby improve sleep quality and daytime
function and reduce medical comorbidities.
Weight Loss
Given the tight link between OSA and overweight/obesity, most patients warrant
counseling on strategies for shedding excess body weight. There is evidence that
bariatric surgery may improve OSA severity and blood pressure control [ 51 ].
Although it was initially hoped that CPAP might help patients to lose weight, sub-
sequent data unfortunately has not supported this notion. Many of the studies exam-
ining the relationship between OSA and weight loss have been limited by small
sample size, retrospective nature, lack of blinding, and imprecise measures of
13 Obstructive Sleep Apnea and Resistant Hypertension