Subjective measurement of insomnia and quality of life in depressed inpatients

Insomnia and major depressive episodes (MDE) have each been associated with quality of life (QOL) deficits. In this study we examined insomnia as an i ndependent predictor of QOL deficits during MDE, and used a secondary analy sis of cross-sectional data. The study was based at the inpatient psychiatr ic ward and included 88 adults (mean age 53; 78% women). We assessed insomn ia severity with the 21-item Hamilton Rating Scale for Depression (HRSD) an d the Beck Depression Inventory (BDI). Measurements of QOL in the week prio r to admission included activities of daily living (ADLs), instrumental ADL s (IADLs), daily living and role functioning, and relation to self and coll eagues (the last two both subscales of the Basis 32). Linear regression mod els used the insomnia items as independent variables and the QOL measures a s the dependent variables, after adjusting for age and nonsleep related dep ression severity. The results showed that 93% of patients endorsed insomnia on the observer-rated HRSD, and 97% endorsed sleep disturbance in the self -rated BDI. However, the insomnia items on the HRSD and BDI showed poor con current validity. Increasing severity of insomnia on the HDRS was associate d with better QOL, while increasing severity of insomnia on the BDI was ass ociated with worse QOL. We conclude that the BDI and HRSD do not produce eq uivalent measures of insomnia severity in depressed inpatients, and each in somnia measure has a unique relationship with QOL.