PREVALENCE OF DSM-IV DIAGNOSTIC-CRITERIA OF INSOMNIA - DISTINGUISHINGINSOMNIA RELATED TO MENTAL-DISORDERS FROM SLEEP DISORDERS

Epidemiological studies of insomnia in the general population have rep orted high prevalence rates. However, few have applied diagnostic crit eria from existing classification systems. Consequently, it is not pos sible to determine whether subjects suffered from a sleep disorder or whether the insomnia constituted a symptom of a mental disorder. Insom nia and its relationship with other mental disorders was investigated in the general population using DSM-IV criteria. A representative samp le of 5622 subjects from the French population were interviewed about their sleep habits over the telephone by lay interviewers. The course and content of interviews were customized by means of the Sleep-Eval k nowledge-based system. A total of 18.6% of the sample reported insomni a complaints. The presence of insomnia complaints, lasting for at leas t one month with daytime repercussions was found for 12.7% of the samp le. Subsequently, subjects were classified according to the Sleep Diso rder decision-making process proposed by the DSM-IV classification, bu t without the recourse of polysomnographic recordings. Specific sleep disorder diagnoses were given for 5.6% of the sample, mostly as insomn ia related to another mental disorder; primary insomnia was given for 1.3% of the sample. Primary mental disorder diagnoses were supplied fo r 8.4% of the sample, mostly as generalized anxiety disorder. The resu lts of this investigation emphasize the need to use classifications to determine whether subjects with insomnia complaints suffer from a sle ep disorder or whether insomnia constitutes a symptom of some other me ntal disorder. These distinctions are of utmost importance as they hav e a bearing on the choice of treatment. Conversely, diagnoses were obt ained by lay interviews, which may have caused a lack of recognition a nd/or discrimination for light or borderline symptomatology. (C) 1997 Elsevier Science Ltd.