Longitudinal Course of Depression Scores with and without Insomnia in Non-Depressed Individuals: A 6-Year Follow-Up Longitudinal Study in a Korean Cohort.

Stanford University, Department of Psychiatry
Sleep (Impact Factor: 5.06). 01/2013; 36(3):369-76. DOI: 10.5665/sleep.2452
Source: PubMed

ABSTRACT This is a population-based longitudinal study that followed insomnia symptoms over a 6-year period in non-depressed individuals. The purpose of the study was to (1) investigate the longitudinal course of depression based on number of insomnia episodes; and (2) describe longitudinal associations between insomnia and depression, and insomnia and suicidal ideation.
Population-based longitudinal study.
Community-based sample from the Korean Genome and Epidemiology Study (KoGES).
1,282 non-depressed individuals (44% male, mean age 52.3 ± 7.14 years).
This study prospectively assessed insomnia, depression, and suicidal ideation with 4 time points. Individuals were classified into no insomnia (NI), single episode insomnia (SEI), and persistent insomnia (PI; ≥ insomnia at 2+ time points) groups based on number of times insomnia was indicated. Mixed effects modeling indicated that depression scores increased significantly faster in the PI group compared to the NI (P < 0.001) and SEI (P = 0.02) groups. Additionally, the PI group had significantly increased odds of depression as compared to NI or SEI (OR 2.44, P = 0.001) groups, with 18.7% meeting criteria for depression compared to the NI (5.3%) and SEI (11.6%) groups at end point. The PI group also had significantly increased odds of suicidal ideation as compared to NI or SEI (OR 1.86, P = 0.002) groups.
Persistent insomnia significantly increases the rate in which depression occurs over time in non-depressed individuals, which ultimately leads to higher risk for depression. Additionally, having persistent insomnia also increased the risk of suicidal ideation. CITATION: Suh S; Kim H; Yang HC; Cho ER; Lee SK; Shin C. Longitudinal course of depression scores with and without insomnia in non-depressed individuals: a 6-year follow-up longitudinal study in a Korean cohort. 2013;36(3):369-376.

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May 30, 2014