Sleep is the most important biological circadian rythm. Researches have shown that sleep deprivation causes reduction of hypothalamus function, decrease glucose tolerance and increase cardio-vascular diseases, hypertension and also decrease their mental and intellectual activity of human. This research investigate insomnia in adult people (Kashan city,Iran.)

This cross-sectional research has been done in Kashan,2008 by using classified randomized sampling in 39 health centers among persons with 18 years old and over (N= 1155). Written consent was taken from subjects, and all of them answered to demographic questionnaire,and researcher-made insomnia questionnaire. Test-retest Reliability of this test was 99% and its internal consistency was 82% by using α kronbach. Data was analyzed by using Fisher exact test.

Prevalence of insomnia was (n=684, 59.2%). The highest rate of insomnia were found among adult with age of 42 to 65 years old (n=266, 67.9%) and then in sex of feminity (n=387, 56.5%). There was significant relationship between insomnia and psychiatric history [PV< 0/0001, OR=2.24], sleep disorder in family [PV< 0/0001, OR=4.67] and drinking caffeine before sleep [PV< 0/001, OR=1.64].

The majority of adult person suffer from insomnia and most sleep problems are observed among middle age group. Since sleep disorders can be related to social, psychological and physical problems, paying attention to quality and hygiene sleep in general population is essential.