Sleep Disordered Breathing in Gulf War Illness and the Effect of Nasal CPAP Treatment
Condition: Apnea, Sleep; Chronic Fatigue Syndrome
MeSH terms: Fatigue Syndrome, Chronic; Sleep Apnea Syndromes; Syndrome; Fatigue
Study type: Interventional

Summary: 
      The purpose of this study is to determine any sleep disordered breathing in veterans with
      Gulf War Syndrome (GWS) and compare it to healthy normal asymptomatic Gulf War veterans. This
      study will also determine the effect of treatment with continuous positive airway pressure on
      veterans with Gulf War Syndrome.

        1. The investigators hypothesize that sleep complaints (insomnia, un-refreshing sleep and
           daytime fatigue) among GWS patients are related to increased sleep fragmentation
           secondary to the presence of sleep disordered breathing in GWS patients.

        2. The investigators hypothesize that increased collapsibility of the upper airway during
           sleep with the development of inspiratory flow limitation (IFL) and sleep disordered
           breathing causes the increased sleep fragmentation in GWS patients.

        3. The investigators hypothesize that correction of IFL and sleep disordered breathing in
           GWS patients will result in an improvement of their sleep quality resulting in an
           improvement of their sleep complaints and other functional symptoms.
    

Detailed description: 
      Hypothesis 1: To demonstrate that compared to Gulf War Veterans without GWS, GWS patients
      have decreased total sleep and increased sleep fragmentation due to the presence of sleep
      disordered breathing

      In order to accomplish this goal and subsequent goals, we will assemble two samples of Gulf
      War veterans. The first will be a sample of male GWS patients and the second will be a sample
      of male Gulf War veterans without GWS (Gulf War veteran control group).

      All of the GWS patients will be registered in the Gulf War Veterans Registry. To avoid
      referral bias favoring the presence of IFL during sleep and sleep disordered breathing, we
      will enroll GWS patients by contacting them from the Registry and inviting them to
      participate. Gulf War veteran controls will be recruited in the same way and by
      advertisement. Prospective study participants will be screened on several self-report
      instruments to determine eligibility and assignment to the GWS group or to the Gulf War
      veteran control group.

      Criteria for assignment to the GWS group are scores above the designated clinical cutpoint on
      each of three instruments measuring , fatigue, pain and cognitive dysfunction.

        1. Fatigue during the preceding week will be assessed using the fatigue severity scale, a
           10-item instrument measuring the level of disability related to fatigue (increasing
           disability rated 1-7).

        2. Pain during the preceding week will be assessed using a pain visual analog scale (VAS;
           increasing pain rated 0-10 ).

        3. Cognitive dysfunction during the preceding week, increasing difficulty with memory,
           ability to think, and ability to concentrate will be assessed by VAS (increasing
           cognitive dysfunction rated 0-10 ).

      Conversely, criteria for assignment to the GW Veteran control group will require scores in
      the non-clinical range on each of those instruments. Every subject will have a full night
      polysomnogram.

      Hypothesis 2: To demonstrate that the presence of IFL and sleep disordered breathing during
      sleep among GWS patients distinguishes them from Gulf War veterans without GWS

      A second sleep study will be used to accomplish this second objective. Using precise methods,
      we will quantify the prevalence of IFL during sleep in GWS patients and in Gulf War veteran
      controls. Following completion, each study will be staged using Rechtschaffen and Kales
      criteria. From each study, 3 three minute periods of continuous NREM sleep (a total of
      approximately 120 breaths) will be randomly selected and analyzed for the prevalence of flow
      limited breaths. During the three minute periods, all of the breaths will be analyzed whether
      they occur during sleep or during brief (< 15 second) arousals.

      Hypothesis 3: To demonstrate that relief of IFL during sleep and sleep disordered breathing
      will result in improvement of the functional symptoms of GWS patients

      We will accomplish this utilizing a masked parallel group of sham-control and treatment trial
      of nasal continuous positive airway pressure (CPAP) in GWS patients. Functional symptoms (
      fatigue, pain and cognitive dysfunction) will be assessed using validated, self-report
      questionnaires and daily ratings of symptoms.
    

Intervention name(s): Nasal CPAP treatment during sleep
Intervention type(s): Other
Intervention description(s): After documenting sleep disordered breathing, GWS subject gets randomized to receive either a therapeutic nasal CPAP or a sham nasal CPAP treatment during sleep, GWS symptoms ( fatigue, pain, and cognitive dysfunction) were assessed by a baseline questionnaires and at 3 week period whether on sham or therapeutic CPAP. The change of symptoms in each group will be compared.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: Fatigue; Functional Somatic Syndrome; Gulf War Syndrome; Sleep apnea; Upper Airway Resistance Syndrome