Objective: To identify and quantify the burden of chronic sleep maintenance insomnia characterized by nighttime awakenings (CINA) among depression and anxiety sufferers.
Method: Data were obtained from the 2006 US National Health and Wellness Survey, an annual cross-sectional study of US adults. Analyses were limited to respondents diagnosed with depression or anxiety. The term CINA was defined as experiencing nighttime awakenings, without difficulty falling asleep, at least twice per week for more than 1 month that have moderate-severe impact on daily life. Outcomes included resource utilization in past 6 months, the Work Productivity and Activity Impairment questionnaire, and the Medical Outcomes Study 8-item Short-Form Health Survey (SF-8). Independent effects of CINA on outcomes adjusting for demographics and comorbidity were assessed using linear regression models.
Results: Among depression sufferers, 643 experienced CINA and 1,675 experienced no insomnia. Among anxiety sufferers, 476 experienced CINA and 1,356 experienced no insomnia. Adjusting for demographics and comorbidity, depression sufferers with CINA had 2.4 more provider visits, 13.2% greater work impairment (among full-time employed), 18.2% greater activity impairment, and SF-8 physical and mental summary scores that were 4.8 and 6.7 points lower than noninsomnia sufferers (P < .001 for all). Anxiety sufferers with CINA had 3.0 more provider visits, 15.8% greater work impairment (among full-time employed), 20.4% greater activity impairment, and SF-8 physical and mental summary scores that were 5.4 and 7.6 points lower than noninsomnia sufferers (P < .001 for all).
Conclusions: Among depression and anxiety sufferers, CINA in relative isolation was associated with a significant negative impact on health care utilization and its associated costs, health-related quality of life, and work productivity.