By Dr. Salvina Puglisi (Specialist in Respiratory Diseases) What is obstructive sleep apnea?
Physiologically, sleep induces a state of relaxation of the body's muscles; when the loss of muscle tone is excessive, the walls of the upper airways
(hypopharynx), begin to vibrate, thus producing the well-known phenomenon of snoring. In
extreme conditions, a real collapse of the walls can occur up to the complete interruption
of breathing, defined as APNEA. This phenomenon is responsible for a
severely compromised quality of sleep, daytime sleepiness, and concentration deficits to the point of being
the cause of serious social and occupational handicaps and clinically risky health conditions
such as cardiovascular diseases (heart attack, arrhythmias) and neurological conditions (stroke). Patients suffering from
OSA often are not aware of their condition because the interruptions in breathing are
associated with sleep, during which the state of consciousness is dulled.
How common is OSA?
Obstructive sleep apnea is an extremely frequent disorder. It is estimated that
it affects 24% of the male population and 9% of the
middle-aged female population. It is a very common disorder; in Italy, patients affected by OSA
who require therapy are about one million six hundred thousand.
When should a patient suspect they suffer from obstructive sleep apnea?
The most common symptoms to consider are: habitual and persistent snoring (present every night for most of the sleep time and for at least six months), breathing pauses during sleep reported by the partner, excessive daytime sleepiness, fatigue or difficulty
concentrating during usual daily activities. It is also important to consider the
presence of other morbid conditions such as obesity, systemic arterial hypertension. These
conditions may be associated with the presence of obstructive sleep apnea. In the presence of the
symptoms mentioned, it is recommended to undergo a sleep study.
How is OSA diagnosed?
The instrumental investigation considered fundamental for diagnosing OSA is polysomnography. It is
a non-invasive test that consists of recording, during one night, all cardiac and respiratory parameters, blood oxygenation, brain activity, and muscle tone. The diagnosis of OSA can easily be performed on an outpatient basis with portable systems, so the patient can sleep at home during the
instrumental investigation.
What is the therapy for OSA?The most appropriate therapeutic choice for controlling obstructive sleep apnea must necessarily take into account several factors, including the severity of the sleep breathing disorder, the severity of associated symptoms, the coexistence of other morbid conditions, and the patient's adherence to the proposed therapy. Very useful, first of all, is following a correct lifestyle, for example, avoiding alcohol consumption especially in the evening hours, avoiding sedatives before going to bed, practicing regular physical exercise, quitting smoking, and, in the presence of excess weight, reducing body weight.
CPAP: this is a mechanical ventilatory device capable of generating a continuous airflow able to prevent the collapse of the upper airway walls, thus avoiding the occurrence of an apneic event.
MANDIBULAR ADVANCEMENT DEVICES (MAD): these are devices that,
inserted into the oral cavity, increase the patency of the upper airways. These aids are
particularly effective in OSAS patients with a positional component, and in those who are
intolerant to ventilatory therapy with CPAP. The application of the MAD causes an advancement
of the mandible with consequent widening of the retro-lingual and retro-palatal spaces, especially in the lateral-lateral direction, preventing their collapsibility. Cephalometric studies, performed with radiological aid, have also shown a lowering of tongue posture with consequent
reduction of the distance between the mandibular plane and the hyoid bone.
There are two types of MAD (Mandibular advancement device): fixed protrusion and
variable protrusion. Variable protrusion MADs are more effective because the possibility of
individual adjustment of mandibular advancement allows the patient to gain greater
benefits in terms of therapeutic resolution.
SURGERY: in SELECTED cases where obstructive sleep apnea is associated with the
presence of anatomical alterations of the upper airways, surgery may represent a
therapeutic option to be adopted. However, it should be noted that, at present, no technique
has proven to be consistently effective as a single procedure for a successful
treatment of OSAS. For this reason, surgery should be considered a therapeutic approach indicated in a limited and well-selected number of patients who must be appropriately
evaluated by medical personnel experienced in the field.