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. 2021 Feb;132(2):545-553.
doi: 10.1016/j.clinph.2020.12.004. Epub 2020 Dec 19.

Optimizing computation of overnight decline in delta power: Evidence for slower rate of decline in delta power in insomnia patients

Jessica R Lunsford-Avery  1 , Jack D Edinger  2 , Andrew D Krystal  3
Affiliations

Optimizing computation of overnight decline in delta power: Evidence for slower rate of decline in delta power in insomnia patients

Jessica R Lunsford-Avery et al. Clin Neurophysiol. 2021 Feb.

Abstract

Objective: To determine the best of commonly used methods for computing the rate of decline in non-rapid eye movement (NREM) sleep EEG delta power overnight (Delta Decline) in terms of vulnerability to missing data and to evaluate whether this rate is slower in insomnia patients than healthy controls (HC).

Methods: Fifty-one insomnia patients and 53 HC underwent 6 nights of polysomnography. Four methods for estimating Delta Decline were compared (exponential and linear best-fit functions using NREM (1) episode mean, (2) peak, and (3) total delta power and (4) delta power for all available NREM epochs). The best method was applied to compare groups on linear and exponential rates of Delta Decline.

Results: Best-fit models using all available NREM epochs were significantly less vulnerable to deviation due to missing data than other methods. Insomnia patients displayed significantly slower linear and exponential Delta Decline than HC.

Conclusions: Computing Delta Decline using all available NREM epochs was the best of the methods studied for minimizing the effects of missing data. Insomnia patients display slower Delta Decline, which is not explained by differences in total sleep time or wake after sleep onset.

Significance: This study supports using all available NREM epochs in Delta Decline computation and suggests a slower rate in insomnia.

Keywords: Delta power; EEG; Homeostatic sleep drive; Insomnia disorder; Spectral analysis.

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Conflict of interest statement

Declaration of Competing Interest Dr. Lunsford-Avery does not have any conflicts of interest to declare. Dr. Edinger has received research support from Merck and Dr. Krystal has received research support and/or consulting fees from Janssen Pharmaceuticals, Axsome Pharmaceutics, Reveal Biosensors, The Ray and Dagmar Dolby Family Fund, and the National Institutes of Health, Adare, Big Data, Eisai, Evecxia, Ferring Pharmaceuticals, Galderma, Harmony Biosciences, Jazz Pharmaceuticals, Millenium Pharmaceuticals, Merck, Neurocrine Biosciences, Pernix, Otsuka Pharmaceuticals, Sage, and Takeda.

Figures

Figure 1.
Figure 1.
Group differences in slope of delta power overnight. Asterisk (*) denotes p < .05. Note: for ease of interpretation, original values are shown prior to BoxCox transformation.
Figure 2.
Figure 2.
Best fit line of delta power over the night with 95% confidence limits in insomnia patients versus healthy controls.
Figure 3.
Figure 3.
Best fit exponential function of delta power over the night with 95% confidence limits in insomnia patients versus healthy controls.
Figure 4.
Figure 4.
Group differences in initial delta power peak. Asterisk (*) denotes p < .05. Note: for ease of interpretation, original values are shown prior to BoxCox transformation.
See this image and copyright information in PMC

References

    1. Achermann P, Dijk DJ, Brunner DP, Borbely AA. A model of human sleep homeostasis based on EEG slow-wave activity: quantitative comparison of data and simulations. Brain Res Bull 1993;31(1–2):97–113. - PubMed
    1. American Psychiatric Association., American Psychiatric Association. Task Force on DSM-IV. Diagnostic and statistical manual of mental disorders 4th ed. Washington, DC: American Psychiatric Association, 1994. xxvii, 886 p. p.
    1. American Psychiatric Association., American Psychiatric Association. Work Group to Revise DSM-III. Diagnostic and statistical manual of mental disorders 3rd ed. Washington, DC: American Psychiatric Association, 1987. xxix, 567 p. p.
    1. Armitage R, Emslie GJ, Hoffmann RF, Rintelmann J, Rush AJ. Delta sleep EEG in depressed adolescent females and healthy controls. J Affect Disord 2001;63(1–3):139–48. - PubMed
    1. Armitage R, Hoffmann R, Fitch T, Trivedi M, Rush AJ. Temporal characteristics of delta activity during NREM sleep in depressed outpatients and healthy adults: group and sex effects. Sleep 2000;23(5):607–17. - PubMed

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