Associations of nonrestorative sleep with insomnia, depression, and daytime function

Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USA.
Sleep Medicine (Impact Factor: 3.15). 12/2010; 11(10):965-72. DOI: 10.1016/j.sleep.2010.08.007
Source: PubMed


Nonrestorative sleep (NRS) complaints are common but associations with insomnia, daytime function or depressive symptoms are not well-established. This study aims to (1) describe insomnia related symptoms and sleep quality in those with NRS compared to those with no NRS; (2) identify the independent associations between NRS, insomnia severity, and depression; and (3) identify the association between NRS and daytime function independent of insomnia severity and depression.
Cross sectional survey of enrollees at a health plan in the Midwestern United States.
Respondents were surveyed about the presence and frequency of NRS complaints, depression, insomnia severity and related symptoms. Multivariate regression was used to examine the study's three research aims.
Study sample consisted of 541 subjects with NRS and 717 who reported never experiencing any NRS symptoms.
We found a statistically significant interaction between NRS and total sleep duration such that the association between sleep duration and sleep quality was attenuated in those with NRS compared to those without NRS (b=-0.26, SE=0.07, p<0.0001). In multivariate analysis, subthreshold, moderate and severe insomnia were associated with NRS (OR [95%CI]=5.93 [4.24-8.31], 9.22 [6.15-13.83] and 6.10 [3.34-11.14], respectively). NRS was independently associated with daytime physical function, cognitive function and emotional function OR [95%CI]=2.21 [1.59-3.08], 1.90 [1.37-2.64] and 1.71 [1.23-2.36], respectively.
NRS is a complex concept that should be further defined and studied in the larger context of sleep quality, other insomnia related symptoms, daytime function and depression.

Download full-text


Available from: Charles M Morin, May 05, 2015
20 Reads
  • Source
  • [Show abstract] [Hide abstract]
    ABSTRACT: A new algorithm for adaptively steering antenna pattern nulls while maintaining a pattern maximum on a desired signal is described. The derivation is carried out by maximizing an estimate of the signal-power-to-interference-power ratio. The resulting algorithm employs double loops; one set maximizes the desired signal power and the other set minimizes the interference power. The MAXIMIN algorithm does not require detailed knowledge of the received signal. Rather, it requires only that the desired signal plus interference and noise be separated from interference and noise alone. A detailed simulation of a spread-spectrum (FH/PN) modem incorporating the MAXIMIN algorithm has been developed. The simulation incorporates all known hardware effects having a significant impact on the operation of the algorithm such as: differing group delays of critical filters, nonlinear effects in the cross-correlation multipliers, limited bit resolution in A/D and D/A converters, and mutual coupling between the array elements. Excellent performance in terms of convergence speed and final signal-to-noise ratio is obtained over a wide range of interference conditions. This approach appears to be well suited to frequency-hopping modems.
  • Sleep Medicine 11/2010; 11(10):961-2. DOI:10.1016/j.sleep.2010.10.001 · 3.15 Impact Factor
Show more