Prevalence and clinical characteristics of insomnia and its subtypes in the Korean elderly

• Published in: Archives of gerontology and geriatrics 2017-01, Vol.68, p.68-75
• Main Authors: Kim, Ki Woong, Kang, Suk-Hoon, Yoon, In-Young, Lee, Sang Don, Ju, Gawon, Han, Ji Won, Kim, Tae Hui, Lee, Chung Suk, Kim, Tae
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Depression; Diagnostic and Statistical Manual of Mental Disorders; Elderly; Female; Humans; Insomnia; Insomnia subtype; Internal Medicine; Male; Middle Aged; Prevalence; Psychiatric Status Rating Scales; Republic of Korea - epidemiology; Risk Factors; Sleep Initiation and Maintenance Disorders - diagnosis; Sleep Initiation and Maintenance Disorders - epidemiology; Sleep Initiation and Maintenance Disorders - etiology
• ISSN: 0167-4943; 1872-6976
• DOI: 10.1016/j.archger.2016.09.005

Abstract Background Insomnia is known to be associated with psychiatric disorders, other sleep disorders and medical conditions, but the prevalence of insomnia diagnosis has never been estimated according to its subtypes. We studied the prevalence and clinical characteristics of insomnia diagnosis and its subtypes in the Korean elderly population. Methods Among 1423 sampled elderly individuals aged 60 years or older, 881 subjects participated in this study. The Athens Insomnia Scale was applied to detect insomnia symptoms, and insomnia diagnosis was finally evaluated using the international classification of sleep disorders, 2nd edition. To define insomnia subtypes, the DSM-IV-based interview, detailed history on sleep disorders and semi-structured interview for medical conditions were performed. Subsyndromal depression was defined when depressive symptoms did not meet the criteria for depressive disorders. Results The prevalence of insomnia disorder was 32.8% in all subjects, with the prevalence being significantly higher in women than in men (37.9% vs. 25.2%; p < 0.001). The prevalence of insomnia subtypes was as follows; psychophysiological insomnia (PI), 20.5%; insomnia due to mental disorder 7.2%; insomnia due to general medical conditions 2.9%; insomnia in other sleep disorders 2.2%, and insomnia due to substance use 0.2%. Among subjects with PI, subsyndromal depression was diagnosed in 53.7%. Conclusions Nearly one third of Korean elderly individuals suffer from insomnia and insomnia patients showed diverse comorbid conditions, especially depressive symptoms. By establishing insomnia subtypes, we can plan to treat comorbid conditions as well as insomnia itself.