Leslie M. Swanson

Sleep disorders and work performance: Findings from the 2008 National Sleep Foundation Sleep in America poll

Chronic sleep deprivation is common among workers, and has been associated with negative work outcomes, including absenteeism and occupational accidents. The objective of the present study is to characterize reciprocal relationships between sleep and work. Specifically, we examined how sleep impacts work performance and how work affects sleep in individuals not at‐risk for a sleep disorder; assessed work performance outcomes for individuals at‐risk for sleep disorders, including insomnia, obstructive sleep apnea (OSA) and restless legs syndrome (RLS); and characterized work performance impairments in shift workers (SW) at‐risk for shift work sleep disorders relative to SW and day workers. One‐thousand Americans who work 30 h per week or more were asked questions about employment, work performance and sleep in the National Sleep Foundation’s 2008 Sleep in America telephone poll. Long work hours were associated with shorter sleep times, and shorter sleep times were associated with more work impairments. Thirty‐seven percent of respondents were classified as at‐risk for any sleep disorder. These individuals had more negative work outcomes as compared with those not at‐risk for a sleep disorder. Presenteeism was a significant problem for individuals with insomnia symptoms, OSA and RLS as compared with respondents not at‐risk. These results suggest that long work hours may contribute to chronic sleep loss, which may in turn result in work impairment. Risk for sleep disorders substantially increases the likelihood of negative work outcomes, including occupational accidents, absenteeism and presenteeism.

A meta-analysis of imagery rehearsal for post-trauma nightmares: effects on nightmare frequency, sleep quality, and posttraumatic stress.

This meta-analysis evaluates the efficacy of imagery rehearsal as a treatment for nightmares, general sleep disturbance, and symptoms of post-traumatic stress. Bibliographic databases and cited references were searched to identify clinical trials of imagery rehearsal in individuals with post-trauma nightmares. Thirteen studies met inclusion criteria and reported sleep and post-traumatic stress outcomes in sufficient detail to calculate effect sizes. Results indicate that imagery rehearsal had large effects on nightmare frequency, sleep quality, and PTSD symptoms from the initial to post-treatment assessments. These effects were sustained through 6 to 12 months follow-up. Furthermore, interventions that included both imagery rehearsal and cognitive behavioral therapy for insomnia resulted in greater treatment-related improvement in sleep quality than imagery rehearsal alone. Combined treatment did not improve outcomes for PTSD or nightmares. Notably, effect sizes were small in the single study that included an active-treatment control condition. Future research should identify necessary and sufficient components of interventions for trauma-related sleep disturbance and post-traumatic stress (e.g., exposure, cognitive reappraisal, sleep and circadian regulation).

A Combined Group Treatment for Nightmares and Insomnia in Combat Veterans: A Pilot Study

Insomnia and nightmares are hallmarks of posttraumatic stress disorder (PTSD). Sleep disturbances in PTSD negatively impact clinical course and functioning. In this open clinical trial, the preliminary effects of a combined treatment for insomnia and nightmares in combat veterans with PTSD were assessed. Ten combat veterans participated in a 10-session group treatment combining cognitive-behavioral therapy for insomnia with exposure, rescripting, and relaxation therapy. Participants maintained daily sleep and dream diaries and completed self-report measures of sleep quality and PTSD symptoms pre- and posttreatment. Participants reported improvements in sleep and nightmares following treatment. Future research using controlled designs to evaluate this treatment is warranted.

Relationships Among Depression, Anxiety, and Insomnia Symptoms in Perinatal Women Seeking Mental Health Treatment

BACKGROUND Depression and anxiety symptoms are commonly experienced by women during the perinatal period. Changes in sleep and sleep quality are typical throughout pregnancy and early postpartum. However, little is known about relationships between insomnia symptoms and psychiatric symptoms in perinatal women. The objective of the present study is to characterize the burden of insomnia symptoms in perinatal women seeking outpatient psychiatric treatment and to examine relationships between insomnia and symptoms of depression and anxiety. METHODS Data from 257 pregnant or postpartum women who sought outpatient psychiatric treatment at a university hospital-affiliated clinic were extracted from an existing clinical management database. Data included validated self-report measures assessing insomnia (Insomnia Severity Index [ISI]), mood (Edinburgh Postnatal Depression Scale [EPDS]), and generalized anxiety (Penn State Worry Questionnaire [PSWQ]). RESULTS Fifty-two percent of women reported symptoms of insomnia, 75% reported symptoms of depression, and 61% reported symptoms of generalized anxiety. After controlling for PSWQ, the partial correlation between EPDS and ISI was 0.15 and 0.37 for pregnant and postpartum women, respectively. After controlling for EPDS, the partial correlation between PSWQ and ISI was 0.20 and 0.12 for pregnant and postpartum women, respectively. Women with clinically significant ISI scores had significantly higher odds for reporting symptoms consistent with depression (odds ratio [OR] 7.7) and generalized anxiety (OR 2.55) compared to women with lower ISI scores. CONCLUSIONS Insomnia symptoms affected a significant proportion of the perinatal women in this sample. These symptoms are linked to symptoms of depression and anxiety in treatment-seeking pregnant and postpartum women. Perinatal women seen in psychiatric treatment settings should be routinely screened for sleep problems.

An Open Pilot of Cognitive-Behavioral Therapy for Insomnia in Women with Postpartum Depression

Sleep disturbances and depression are commonly experienced by postpartum women. We evaluated the preliminary efficacy of a modified version of cognitive-behavioral therapy for insomnia on mood, sleep, and fatigue in postpartum women with insomnia and depression in an open pilot study. Twelve postpartum women participated in five weekly individual treatment sessions. Statistically significant improvements were observed in sleep diary-rated sleep efficiency and total wake time, and subjective mood, insomnia severity, sleep quality, and fatigue. Further evaluation of the treatment using a controlled design is warranted.

Employment and drowsy driving: a survey of American workers

Drowsy driving is a major public health problem in the United States. Employment characteristics affect sleep, yet little is known about relationships between employment variables and drowsy driving. This study examined employment correlates (specifically, hours worked per week and shift work) and rates of self-reported drowsy driving, falling asleep while driving, and traffic crashes due to sleepiness in 1,000 employed adults who completed a telephone survey conducted by the National Sleep Foundation. Working > 40 hr per week and shift work were associated with increased risk for drowsy driving (ps ≤ .05). Odds ratios for falling asleep behind the wheel were higher in shift workers with symptoms of insomnia or excessive sleepiness relative to day workers and shift workers without sleep complaints (p ≤ .05).

Reciprocal dynamics between self-rated sleep and symptoms of depression and anxiety in young adult women: a 14-day diary study

OBJECTIVES The objective of this study was to characterize the day-to-day associations among sleep disturbance, depression, and anxiety in a sample of young adult women. METHODS One hundred and seventy-one women (20.1 ± 3.3 years) completed in-laboratory baseline assessment followed by daily online surveys across a two-week period. Daily measures included the Mood and Anxiety Symptom Questionnaire-Short Form to assess shared and disorder-specific symptoms of depression and anxiety (general distress, anhedonic depression, and anxious arousal), as well as self-reported total sleep time (TST), sleep-onset latency (SOL), and sleep quality (SQ). RESULTS Findings supported bidirectional day-to-day relationships between sleep and affective symptoms. When women felt greater general distress (shared features of anxiety and depression), they experienced longer SOL and worse SQ at night. Specificity among depression, anxiety, and sleep disturbance was observed such that higher levels of depression-specific anhedonia presaged longer SOL, shorter TST, and poorer SQ. In the other direction, when women had poor-quality sleep, they later experienced greater anhedonic depression and anxious arousal. The influence of TST on anhedonia was complex such that a single night of short sleep led to less anhedonic depression the next day, whereas women who obtained shorter sleep across the two-week period reported greater anhedonia. CONCLUSIONS Reciprocal dynamics between nightly sleep disturbance and daily experiences of depression and anxiety may serve as a process by which insomnia, depression, and anxiety develop into comorbid clinical states over time in women. The associations of anhedonic depression with nightly sleep disturbance and chronic short sleep were especially toxic, offering insight into daily mechanisms driving the most prevalent phenotype of comorbid insomnia.

The role of childhood trauma and PTSD in postpartum sleep disturbance.

Despite robust associations between postpartum sleep difficulties and maternal psychopathology, little attention has been paid to the role of childhood trauma and posttraumatic stress disorder (PTSD). In the present study, we examined sleep complaints in postpartum women with a history of childhood trauma compared to postpartum women who were not exposed to childhood trauma. Participants (N = 173) completed questionnaires by telephone at 4-months postpartum. After adjusting for nuisance variables, there were significantly higher rates of sleep disturbance (falling asleep and staying asleep) for women with a past history of neglect (OR = 4.84, p = .036 and 5.78, p = .006, respectively), physical abuse (OR = 9.20, p = .002 and 3.84, p = .044, respectively), and physical abuse with sexual abuse (OR = 5.95, p = .011 and 3.56, p = .045, respectively). Current PTSD was significantly associated with trouble staying asleep (OR = 4.21, p = .032) whereas recovery from PTSD was associated with trouble falling (OR = 4.19, p = .015) and staying asleep (OR = 3.69, p = .011). Our findings affirm the contribution of childhood trauma and PTSD to postpartum sleep.

Relationships between circadian measures, depression, and response to antidepressant treatment: A preliminary investigation

Few studies have examined relationships between circadian rhythms and unipolar major depressive disorder. Further, no study to date has examined circadian markers as predictors of response to depression treatment. In the present study, we examined associations between circadian timing and its alignment with sleep and depression severity in 30 adults with major depressive disorder who completed a randomized controlled trial of two weeks of time in bed (TIB) restriction administered adjunctive to fluoxetine, with a focus on sex differences. Thirty adults with major depressive disorder received 8 weeks of fluoxetine 20-40 mgs and were randomized to 8h TIB or 6h TIB for the first 2 weeks. Participants in the 6h TIB condition were further randomized to a delayed bedtime or advanced risetime group. Circadian measures included dim light melatonin onset (DLMO) and the difference between DLMO and midsleep point (i.e., phase angle difference). Depression was assessed using the Hamilton Rating Scale for Depression. For females, a phase delay after 2 weeks of fluoxetine and the experimental TIB manipulation was associated with a poorer response to fluoxetine, and depression severity was negatively correlated with phase angle difference, whereas males showed a positive correlation between depression severity and phase angle difference.

Effects of Restricted Time in Bed on Antidepressant Treatment Response: A Randomized Controlled Trial

OBJECTIVE Antidepressant response onset is delayed in individuals with major depressive disorder (MDD). This study compared remission rates and time to remission onset for antidepressant medication delivered adjunctively to nightly time in bed (TIB) restriction of 6 hours or 8 hours for the initial 2 weeks. METHODS Sixty-eight adults with DSM-IV-diagnosed MDD (mean ± SD age = 25.4 ± 6.6 years, 34 women) were recruited from September 2009 to December 2012 in an academic medical center. Participants received 8 weeks of open-label fluoxetine 20-40 mg and were randomized to 1 of 3 TIB conditions for the first 2 weeks: 8-hour TIB (n = 19); 6-hour TIB with a 2-hour bedtime delay (late bedtime, n = 24); or 6-hour TIB with a 2-hour rise time advance (early rise time, n = 25). Clinicians blinded to TIB condition rated symptom severity weekly. Symptom severity, remission rates, and remission onset as rated by the 17-item Hamilton Depression Rating Scale were the primary outcomes. RESULTS Mixed effects models indicated lower depression severity for the 8-hour TIB compared to the 6-hour TIB group overall (F₈, ₂₂₆.₉ = 2.1, P < .05), with 63.2% of 8-hour TIB compared to 32.6% of 6-hour TIB subjects remitting by week 8 (χ²₁ = 4.9, P < .05). Remission onset occurred earlier for the 8-hour TIB group (hazard ratio = 0.43; 95% CI, 0.20-0.91; P < .03), with no differences between 6-hour TIB conditions. CONCLUSIONS Two consecutive weeks of nightly 6-hour TIB does not accelerate or improve antidepressant response. Further research is needed to determine whether adequate sleep opportunity is important to antidepressant treatment response. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT01545843.