Elsevier

Clinical Psychology Review

Volume 59, February 2018, Pages 118-125
Clinical Psychology Review

Review
Insomnia in United States military veterans: An integrated theoretical model

https://doi.org/10.1016/j.cpr.2017.11.005Get rights and content

Highlights

  • •

    Chronic insomnia problems are highly prevalent among US military Veterans.

  • •

    Existing theoretical models view insomnia as a unidirectional phenomenon.

  • •

    An integrated model is proposed that explains insomnia as a chronic, cyclical problem.

  • •

    Insomnia should be viewed as a both a consequence and predictor of stress.

Abstract

Marked by difficulty falling or staying asleep and/or poor sleep leading to daytime dysfunction, insomnia contributes to functional impairment, poor health, and increased healthcare utilization when left untreated. As many as two-thirds of Iraq and Afghanistan military veterans complain of insomnia. Older veterans of prior conflicts report insomnia occurring since initial service, suggesting a chronic nature to insomnia in this population. Despite insomnia's high prevalence and severe consequences, there is no theoretical model to explain either the onset or chronicity of insomnia in this growing patient population. Existing theories view insomnia as an acute, unidirectional phenomenon and do little to elucidate long-term consequences of such problems. Existing theories also fail to address mechanisms by which acute insomnia becomes chronic. This paper presents an original, integrated theoretical model that draws upon constructs from several prominent behavioral medicine theories to reconceptualize insomnia as a chronic, cyclical problem that is both a consequence and predictor of stress. Additional research examining the relationships between stress, sleep, resilience, and outcomes of interest could inform clinical and research practices. Addressing sleep problems early could potentially enhance adaptive capacity, thereby reducing the risk for subsequent negative outcomes.

Introduction

Sleep is a basic biological need responsible for a range of restorative functions including emotion regulation and memory consolidation, muscle and tissue repair, and stress hormone regulation (Dement & Vaughan, 1999). Despite its necessity, sleep is often ignored as a core health behavior, rarely addressed within biopsychosocial assessments or routine primary care visits, and generally not integrated into chronic disease management programs. Sleep problems are particularly common among United States military veterans, with one-half to two-thirds of the 2.5 million U.S. military troops who served in Afghanistan (Operation Enduring Freedom, OEF) and Iraq (Operation Iraqi Freedom, OIF) complaining of insomnia problems upon returning home (Amin et al., 2010, Seelig et al., 2011). Insomnia complaints are also prevalent among veterans of earlier wars, including Vietnam and Korea conflicts. Additionally, many of these older veterans report that sleep problems initially began during or immediately following their military service and have persisted in the decades since separating from the military (Hughes and Martin, 2015, Ryden et al., 2015).

These findings suggest insomnia problems are chronic within veteran populations; yet, a lack of longitudinal data prohibits researchers from identifying mechanisms that contribute to such chronicity and from understanding how such problems change over a veteran's life course. Given sleep problems are tied to a number of negative physical and psychological outcomes (Fernandez-Mendoza & Vgontzas, 2013), it is critical that researchers and clinicians develop a better understanding of this growing problem. The overarching goal of this paper is to offer a theoretical model of insomnia in the veteran population. Although this model can be applied to veterans of all ages and military cohorts, a major goal of the model is to place insomnia-like sleep problems of recently returning OEF/OIF veterans into a larger, lifespan context as a means of advocating for additional research on the role sleep problems may play in longterm health and aging. While military-specific stressors will be addressed, we believe that elements of this integrated model can be applied to other patient populations, including those who have experienced significant stress or trauma.

Section snippets

Insomnia in military veterans

Chronic Insomnia Disorder is a common behavioral sleep disorder clinically defined as dissatisfaction with sleep quantity or quality marked by complaints of difficulty falling or staying asleep, waking up earlier than desired, or sleep that is non-restorative and the cause of significant daytime impairment. Such problems are not related to other medical or sleep disorders, exist despite adequate opportunity and environment for sleep, and are endorsed three or more nights per week for three

Insomnia and resilience as missing links between military service and poor outcomes

Insomnia problems contribute to negative health outcomes and can become chronic, surfacing repeatedly over one's life course. However, mechanisms contributing to this chronicity have not been identified. The mechanisms linking sleep problems, including insomnia, to new mental health diagnoses remain unclear. However, one hypothesized explanation is that chronic poor sleep reduces one's coping abilities. As a result, when subsequent stressors do arise, individuals with sleep problems respond

Integrated theoretical model

The discussions above suggest that the causes and consequences of insomnia in U.S. military veterans are complex and that sleep may play an important role in longterm mental and physical health. Below, we present an innovative integrated theoretical model that could be used to better understand the growing problem of insomnia among military veterans. This model builds on the 3P Model of Insomnia (Spielman & Glovinsky, 1991). Widely used in clinical assessment and interventions, the 3P Model

Future directions

The proposed theoretical model highlights the etiological and clinical complexity of insomnia in U.S. military veterans, placing a particular emphasis on untreated insomnia problems. Severe sleep problems, such as insomnia, might occur at one point in time, typically triggered by a major life or environmental stressor, but their antecedents are found early in life and their consequences can extend for years or decades beyond the triggering stressful event(s). The model presented herein is meant

Role of funding sources

This work was supported by facilities and resources at the Center of Innovation for Health Services Research in Primary Care at the Durham VAMC (CIN 13-410); Office of Academic Affiliations, VA Health Services Research & Development (Hughes: TPH 21-000); VA Research Career Development Award Program (Ulmer: CDA 09-218); and University of North Carolina Program on Integrative Medicine (Hughes: NIH/NCCIH T32AT003378). None of the funding sources had a role in developing this material, writing the

Contributors

Dr. Hughes developed the first draft of the conceptual model and wrote the first draft of the manuscript. Drs. Ulmer, Gierisch, Hastings, and Howard served as theoretical consultants during the development of the conceptual model and assisted with review and editing of the final manuscript. All authors have contributed to and have approved the final manuscript.

Conflict of interest

The authors have no conflicts of interest to disclose.

Acknowledgments

The authors wish to think Wizdom Powell, PhD, MPH who provided comments on an initial version of the conceptual model and manuscript.

References (90)

  • J.B. Lohr et al.

    Is post-traumatic stress disorder associated with premature senescence? A review of the literature

    American Journal of Geriatric Psychiatry

    (2015)
  • B.S. McEwen et al.

    Sleep deprivation and circadian disruption: Stress, allostasis, and allostatic load

    Sleep Medicine Clinics

    (2015)
  • N.D. Shippee et al.

    Cumulative complexity: A functional, patient-centered model of patient complexity can improve research and practice

    Journal of Clinical Epidemiology

    (2012)
  • E.A. Stanley et al.

    Mindfulness-based mind fitness training: A case study of a high-stress predeployment military cohort

    Cognitive and Behavioral Practice

    (2011)
  • M. Trockel et al.

    Cognitive behavioral therapy for insomnia with veterans: Evaluation of effectiveness and correlates of treatment outcomes

    Behaviour Research and Therapy

    (2014)
  • E.J. Wolf et al.

    Accelerated DNA methylation age: Associations with PTSD and neural integrity

    Psychoneuroendocrinology

    (2016)
  • S. Ahn et al.

    Improvement in sleep problems among the chronic disease self-management program participants

    Family & Community Health

    (2014)
  • American Psychiatric Association

    Desk reference to the diagnostic criteria from DSM-5

    (2013)
  • M. Amin et al.

    War-related illness symptoms among operation Iraqi freedom/operation enduring freedom returness

    Military Medicine

    (2010)
  • J.R. Blosnich et al.

    Disparities in adverse childhood experiences among individuals with a history of military service

    JAMA Psychiatry

    (2014)
  • A.D. Bramoweth et al.

    Deployment-related insomnia in military personnel and veterans

    Current Psychiatry Reports

    (2013)
  • J. Campbell et al.

    Introduction

  • C.A. Castro et al.

    The combat veteran paradox: Paradoxes and dilemmas with reintegrating combat veterans and the agencies that support them

    Traumatology

    (2015)
  • S.T. Charles et al.

    The wear and tear of daily stressors on mental health

    Psychological Science

    (2013)
  • A. DeLongis et al.

    Relationship of daily hassles, uplifts, and major life events to health status

    Health Psychology

    (1982)
  • W.C. Dement et al.

    The promise of sleep: A pioneer in sleep medicine explores the vital connection between health, happiness, and a good night's sleep

    (1999)
  • M.A. Dew et al.

    Healthy older adults' sleep predicts all-cause mortality at 4 to 19 years of follow-up

    Psychosomatic Medicine

    (2003)
  • C.L. Drake et al.

    Sleep reactivity and insomnia: Genetic and environmental influences

    Sleep

    (2011)
  • C.L. Drake et al.

    Stress and sleep reactivity: A prospective investigation of the stress-diathesis model of insomnia

    Sleep

    (2014)
  • C.L. Drake et al.

    Vulnerability to stress-related sleep disturbance and hyperarsoual

    Sleep

    (2004)
  • J. Fernandez-Mendoza et al.

    Insomnia and its impact on physical and mental health

    Current Psychiatry Reports

    (2013)
  • D. Ford et al.

    Epidemiologic study of sleep disturbances and psychiatric disorders: An opportunity for prevention?

    Journal of the American Medical Association

    (1989)
  • M. Garmezy

    Vulnerability research and the issue of primary prevention

    American Journal of Orthopsychiatry

    (1971)
  • P. Gehrman et al.

    Predeployment sleep duration and insomnia symptoms as risk factors for new-onset mental health disorders following military deployment

    Sleep

    (2013)
  • K. Glanz et al.

    Stress, coping, and health behavior

  • N.A. Hamilton et al.

    Sleep and the affective response to stress and pain

    Health Psychology

    (2007)
  • P.L. Haynes et al.

    Motivational enhancement therapy for insomnia in OEF/OIF veterans: A treatment development study

    Sleep

    (2013)
  • C.W. Hoge et al.

    Mild traumatic brain injury in US soldiers returning from Iraq

    New England Journal of Medicine

    (2008)
  • E. Hoge et al.

    Resilience: Research evidence and conceptual considerations for Posttraumtic Stress Disorder

    Depression and Anxiety

    (2007)
  • J. Hughes et al.

    Sleep characteristics in Veterans Affairs Adult Day Health Care participants

    Behavioral Sleep Medicine

    (2015)
  • Institute of Medicine

    Returning home from Iraq and Afghanistan: Assessment of readjustment needs of Veterans, service members, and families

    (2013)
  • M.R. Irwin

    Sleep and inflammation in resilient aging

    Interface Focus

    (2014)
  • B.E. Karlin et al.

    National evaluation of the effectiveness of cognitive behavioral therapy for insomnia among older versus younger veterans

    International Journal of Geriatric Psychiatrty

    (2015)
  • D.A. Katz et al.

    The relationship between insomnia and health-related quality of life in patients with chronic illness

    Journal of Family Practice

    (2002)
  • W.D.S. Killgore et al.

    Impaired decision making following 49 hours of sleep deprivation

    Journal of Sleep Research

    (2006)

    • Cited by (31)

    • Pre-deployment threat learning predicts increased risk for post-deployment insomnia: Evidence from the Marine Resiliency Study

      2022, Behaviour Research and Therapy
      Citation Excerpt :

      Soldiers with a propensity for acquiring excessive, inflexible, or unnecessary threat responses may be more chronically aroused following aversive deployment experiences and thus be at higher risk for developing the persistent sleep-related arousal that often contribute to sleep problems among Veterans (Capaldi et al., 2011; Wright et al., 2011; Wallace et al., 2011; Bramoweth & Germain, 2013). This proposition is also consistent with prevailing models of post-deployment insomnia, which suggest that individuals who react excessively to or cope poorly with deployment-related stressors are at elevated risk for developing insomnia (Bramoweth & Germain, 2013; Hughes et al., 2018). Additionally, there is a well-established link between disruptions in sleep-related processes (e.g., less total sleep time, lower proportion of rapid eye movement [REM] sleep) and abnormal threat learning (Straus et al., 2017; Colvonen et al., 2019; Schenker et al., 2021).

    • What's sleep got to do with it? Longitudinal associations between insomnia, PTSD, and alcohol use among U.S. Veterans

      2022, Addictive Behaviors
      Citation Excerpt :

      Insomnia, a behavioral sleep disorder characterized by dissatisfaction with quality or quantity of sleep, difficulty initiating or maintaining sleep, or waking up earlier than desired, is linked to a wide range of psychological and physical health problems (American Psychiatric Association, 2013). United States military veterans are particularly vulnerable to sleep problems, likely due to irregular sleep schedules established during active duty, combat-related stress, as well as co-occurring mental health problems (Alexander et al., 2016; Hughes et al., 2018; Roth, 2007). In a recent observational study of post-9/11 veterans enrolled in the Veterans Health Administration, 57% met criteria for insomnia (Colvonen et al., 2020), which is over double the prevalence reported in civilian samples (27.3%; Morin & Jarrin, 2013; Olfson et al., 2018).

    • Childhood trauma differentially impacts depression and stress associations with reintegration challenges among post-9/11 U.S. veterans

      2022, Nursing Outlook
      Citation Excerpt :

      Maladaptive behaviors and somatic symptoms are common among veterans and relate to stress and reintegration outcomes. Binge drinking episodes, pain, and sleep impairment are functions of stress responses as well as outcomes of stress, and can worsen reintegration outcomes (Hughes et al., 2018; Sherman et al., 2015; Wu & Graham, 2016). Current 3-month average and presence of mild or higher pain was assessed using the Short Form McGill Pain Questionnaire (Melzack, 1975).

    • Options for Veterans Experiencing Sleep Impairment

      2021, Journal for Nurse Practitioners

    • Analysis of Factors Influencing Insomnia and Construction of a Prediction Model: A Cross-sectional Survey on Rescuers

      2020, Biomedical and Environmental Sciences

    • Worldwide and regional prevalence rates of co-occurrence of insomnia and insomnia symptoms with obstructive sleep apnea: A systematic review and meta-analysis

      2019, Sleep Medicine Reviews
      Citation Excerpt :

      When exploring the prevalence of OSA in patients with insomnia, studies using subjects referred for sleep testing due to a high clinical suspicion for OSA were excluded, because of selection bias. For explorations of both the prevalence rates of insomnia/insomnia symptoms in patients with OSA and of the prevalence of OSA in patients with insomnia, studies using trauma samples or highly suspected trauma samples (i.e., veterans) were excluded, due to the potential specific events underlying their insomnia [41,42] and OSA [43], and that they are not the routine cases seen in hospital or community samples. Traumatic events are defined formally in DSM [37] as an event involving serious injury or potential or actual death that an exposed person experiences (or witnesses), and responds with helplessness, intense fear or horror.

    View all citing articles on Scopus
    View full text
    Published by Elsevier Ltd.