Sleep deprivation or bad quality sleep causes disruptions both in social and professional life due to decreased wakefulness, lack of attention and drowsiness during the day, but the consequences of sleep alterations also include general health risks: higher risk of obesity, hypertension and diabetes when compared to the general population, causing a significant increase in mobility and mortality from cardiovascular disease and the risk of various types of accidents, of which driving accidents are the majority.
Additionally, we also know that the quality of sleep interferes with the homeostasis of the immune system and hormonal regulation.
According to Dr Carlos Glória, “early intervention in alterations of sleep is fundamental, as these situations can be persistent or perpetuate in time, provoking anxiety to the patient as well as to family members. Sleep disorders are not just an individual problem, because sooner or later, they will interfere with everyone who is in contact with this person”.
He explains: “There are several elements that, together, can define the quality of sleep. The first is regularity. The habit of going to sleep and waking up at the same time during the week is part of what is referred to as ‘sleep hygiene’. The second is sleep period continuity, permitting the sequence of all sleep phases (superficial sleep, deep sleep and REM sleep, when we dream). Lastly, the duration, which despite varying with age, should fulfill at least two complete sleep cycles, which corresponds to a minimum of six hours of sleep for adults. Only by meeting all of these requirements can we wake up feeling alert and well-rested.”
The study of nocturnal sleep using equipment that monitors multiple sleep variables (polysomnography) results is one of the most important exams used in the study of pathologies associated with sleep.
The Sleep Lab, which was installed at the Hospital Particular in Alvor over 10 years ago, has undergone significant improvements resulting in additional booking availability.
A Polysomnography or Polygraph Study of Nocturnal Sleep registers a variety of functions which occur during sleep, such as electrical activity of the brain, eye movement, muscular activity, heart rate, respiratory movement and fluxes, levels of oxygen in the blood, among other factors. The analysis of these variables allows for the diagnosis of the majority of sleep pathogens and determines the seriousness of the problem.
There are three types of Polysomnograms.
The simplest study is called Level 3 Polysomnogram and is done in practically all of the units of the HPA Group (clinics and hospitals). It is an outpatient exam where the equipment is connected by the patient and registers whether there is apnoea or hyperpnoea during sleep, snoring as well as oxygen levels.
Level 2 Polysomnogram is a bit more complex. Although it is also done as an outpatient exam, it also allows for staging the phases of sleep, leg movements, and so on. The equipment is connected to the patient at the end of the day at one of the hospitals, sleep at home, just as in the previous study. The equipment is then disconnected the next morning at the hospital once again.
The most complex is the Level 1 polysomnogram. This involves a study in a controlled environment and is done in the hospital. In this exam, the sleep period is also recorded on video, allowing for a more profound analysis and diagnoses of more complex pathologies.
The Multiple Latency Sleep Test is a daytime exam and measures how quickly the patient falls asleep during the day. It can be useful to assess the degree of sleepiness and exclude other sleep disorders.
With this variety of tests possible, the Alvor Hospital is now able to respond and intervene in a wide range of sleep dysfunctions.
By Dr. Carlos Glória
Dr. Carlos Glória is a Pulmonologist and Intensive Care Specialist. He is also head of the Sleep Lab at the HPA Health Group