The Course of Insomnia over One Year: a Longitudinal Study in the General Population in Sweden

Abstract

In summary, the results showed that insomnia is a prevalent condition in the general population associated with negative consequences and is characterized not only by persistence but also by relatively high remission and incidence.

Epidemiology of Insomnia

“…Rates of sleep dissatisfaction, without regard to specific sleep diagnosis, also vary widely (10% to 25%) in the adult population. When using more stringent and operational DSM [2] or Epidemiology of Insomnia 6 ICSD [19] diagnostic criteria, prevalence rates tend to cluster between 6% and 10% [6][7][20][21][22]. These highly variable estimates underscore the need to rely on operational definitions and standardized assessment procedures to derive accurate and comparable prevalence rates across studies.…”

“…Nonetheless, incidence rates vary extensively across studies, depending on the case definition (e.g., symptoms vs. syndrome) and the interval used to track new onset. For instance, four population-based studies using the same 12-month interval between baseline and follow-up assessments revealed incidence rates of 2.8% in Sweden [21], 6.0% in the USA [27], 7.4% in Canada [43], and 15% in the UK [44], with the variability being partly accounted for by different case definitions across studies. For example, the Canadian study found an incidence rate of 30.7% for insomnia symptoms compared to 7.4% for an insomnia syndrome [43].…”

“…The evidence is quite clear that insomnia is often a persistent Epidemiology of Insomnia 12 problem over time, with persistence rates varying as a function of the intervals between assessments. For example, data derived from some of the same longitudinal studies assessing incidence have produced persistence rates over a 1-year period of 31% in the USA [27], 44.4% (syndrome like) in Sweden [21], 69% (symptoms) in the UK [44], and 74% (symptoms and syndromes combined) in Canada [53]. Studies conducted with cohorts of older adults have produced persistence rates of 66.3% [54] for one year, 40% for a 2-year period [55], and 36.1% for a 4-year period [56].…”

Psychometric properties of the Pre-Sleep Arousal Scale in a large community sample

“…This sleep pattern had to be present for at least 3 nights per week. (3) The participant had to report daytime impairment (for symptoms: 'quite much' or more, for function: 'marked negative consequences' or more) [48]. (4) The individual must not meet the criteria for apnea, narcolepsy, restless legs syndrome/periodic limb movement disorder, circadian rhythm disorder, sleepwalking, nightmares or hypersomnia as assessed with the SLEEP-50.…”

Adolescence Sleep Disturbances as Predictors of Adulthood Sleep Disturbances—A Cohort Study

“…Evidence from longitudinal studies to support the chronicity of sleep disturbance, however, is more limited. A number of studies have reported some persistence over shorter periods of time in children, adolescents, adults, and the elderly [4][5][6][7][8]. An 8-year UK longitudinal study [9] found that a third of those who reported insomnia symptoms in 1985 were still reporting these 4 years later (1989), and a further 10% of the 1989 survey continued to report insomnia symptoms in 1993.…”