New Research Shines Light on Insomnia

Insomnia is a disorder characterized by the inability to fall asleep, or stay asleep. Losing sleep at night can have a substantial impact on daytime functioning. Data from a number of sleep studies indicate that about one third of people worldwide experience difficulties with sleep. However, few studies have examined the progress of insomnia over time within the general population. Therefore, it is difficult to estimate what percentage of the population suffers from either persistent or recurrent insomnia, and how many new cases develop over a period of time. Researchers at Orebro University, in Orebro, Sweden, explored the course of insomnia over a one-year period in a random sampling of the Swedish population. The study was designed to focus on the prevalence of the condition, as well as its consequences, persistence, incidence, and potential for remission. They reported on their findings in the journal SLEEP.

Data for the study was based on responses from 1746 participants who completed a questionnaire at baseline, and another after one year. The questionnaire was designed to assess factors associated with quality of sleep. Participants answered questions about sleep patterns during the previous three months. The authors wanted to know how much time participants spent trying to fall asleep at night. Individuals who reported waking up during the night were asked to estimate the amount of time they spent awake. For some, waking up too early in the morning was a problem. Participants were asked to describe any daytime symptoms associated with an inadequate level of sleep. Possible daytime consequences include problems with concentration and memory, headache, lack of energy, aching muscles, tension, sleepiness, irritability, and bad mood.

Data on the prevalence and consequences of insomnia showed that of 1746 participants, 169 reported insomnia at baseline, with 151 at follow-up. About half of participants with insomnia also reported daytime symptoms. Some also reported that insomnia had impacted their work performance and/or leisure and social activities. About 10 percent used sick leave for sleep-related problems, 15 percent had visited a doctor, and 18 percent took sleeping pills. Participants who reported that they slept well also functioned at higher levels during the day. Other data indicated that 4.3 percent of the general population had persistent insomnia, 5.4 percent had intermittent insomnia, and 2.8 percent developed insomnia over the course of a year.

Although the prevailing viewpoint has been that insomnia is a primarily persistent condition, results of this study indicate that it may be either persistent or intermittent, or may develop over time. The authors concluded that insomnia is a condition that varies over time within the general population. Future research may include a focus on the development of useful screening methods to identify people at high risk for insomnia. Early intervention is the best strategy for preventing the onset of chronic insomnia with serious daytime consequences. These results may impact the future of insomnia treatment by shedding new light on a puzzling condition.

Reference

Jansson-Frojmark, M., Linton, S.

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

SLEEP

http://www.betterhealth.vic.gov.au/bhcv2/bhcArticles.nsf/pages/Sleep_problems_insomnia?OpenDocument