The collective term sleep disorder refers to conditions that affect sleep quality, timing, or duration and impact a person’s ability to properly function while they are awake. These disorders can contribute to other medical problems, and some may also be symptoms for underlying mental health issues.
In 1979, the American Sleep Disorders Association published the first classification system dedicated to sleep disorders. Our knowledge and understanding of sleep health has evolved over the past four decades. More than 100 specific sleep disorders have been identified and today’s classifications use complex methodologies to categorize these disorders based on causes, symptoms, physiological and psychological effects, and other criteria. However, most sleep disorders can be characterized by one or more of the following four signs: