ABSTRACT
Insomnia is defined as difficulty with the initiation, maintenance, duration, or quality of sleep resulting in the impairment of daytime functioning despite adequate opportunity and circumstances for sleep (1,2). Although research studies sometimes require a specific quantitative definition, a patient’s subjective judgment that sleep is insufficient, inadequate, or nonrestorative is the most important factor in clinical practice. Insomnia is the most common sleep complaint. Transient insomnia lasts less than one week, and short-term insomnia one to four weeks. Chronic insomnia, insomnia lasting more than one month, affects between 10% and 35% of the population in the western world (3,4). The number of chronic insomniacs rises with age, and women of all ages complain of insomnia more often thanmen (3,5). Insomnia is frequently associatedwith othermedical complaints and psychological symptoms, particularly anxiety, worry, and depression. Stressful life events (difficulties in interpersonal relationships, family discord, problems at work, and financial troubles) may also generate a nonrestorative sleep complaint. Insomnia is not a specific illness or disease, but rather a symptom or consequence of other primary disorders. “Poor quality of sleep” is a common complaint in the family members of chronic insomniacs. However, it is difficult to gauge the extent to which the emotional problems favouring the onset of a sleep disorder in adulthood are due to a genetic predisposition or the result of having lived in a family burdened by affective problems and/or interpersonal conflicts.
