**6.2 Objective assessment**

*Updates in Sleep Neurology and Obstructive Sleep Apnea*

these three main aspects: *Sleep*, *Pain*, and *Psychology*.

**6. Assessment of sleep-pain interaction**

**6.1 Self-reported measurements**

sleep-pain interaction conditions.

research field and practical arena.

is the most common sign of sleep apnea. Furthermore, when snoring and insomnia complaints are considered together, 6% of those patients presented with both symptoms increasing the likelihood of suffering from OSA [59]. The reasons for the higher prevalence of pain in patients with sleep disturbances were discussed previously in

While diagnostic aspects and evaluation of pain were discussed along this chapter and assessment of sleep was also detailed elsewhere in this book, it is important to consider some important diagnostic tools for an adequate assessment of the sleep-pain patient, such as self-reported questionnaires and polysomnography.

An optimal use of self-report measures depends on the clinician's degree of expertise and on the specific goal. There are several screening, diagnostic, and follow up tools which can be used to properly evaluate and manage patients with

Sleep evaluation involves several dimensions and patterns which should be differently assessed according to the main complaint and prior clinical suspicion. A sleep diary is the gold standard for subjective sleep assessment and is always a simple good way to start understanding better the usual sleep pattern of the patient. There is a consensus sleep diary (CSD) [61] that resulted for the collaborative work of both insomnia experts and potential users. This instrument is unique regarding the important related methodological issues that allow to evaluate insomnia in the

Other self-reported instruments commonly used are the Pittsburgh sleep quality index [62], to evaluate sleep quality, the Epworth Sleepiness Scale [63] to evaluate sleepiness which could be intended as an indirect measure of inadequate sleep, the Sleep Questionnaire to characterize sleep depth, and dreams and a the Sleep Disturbance Questionnaire to assess mental anxiety and physical tension. The Global Sleep Assessment Questionnaire (GSAQ ) probably represents the best available screening tool for primary care practice. The chronotype as it could impact the sleep timing and the vulnerabilities for some pain sleep-wake cycle related impairments can be measured by the Morning-Evening Questionnaire [64], while states of sleepiness may be addressed by using the Stanford Sleepiness Scale [65] or the Karolinska Sleepiness Scale [66]. Visual analog scales oriented to sleep quality, sleepiness, or any other qualitative-measured dimension of sleep can also be used

the pathophysiological section and could be related with either peripheral (e.g., release of proinflammatory cytokines and decrease in pain tolerance) or central mechanisms. Often medication, commonly prescribed for pain management, affects breathing during sleep and can even interfere with other common sleeprelated disturbances. For instance, mechanical management for pain control may affect normal respiration predisposing to sleep related breathing disorders [60]. Sleep impairment and chronic pain are also independently related with increased depressive symptoms. It has been speculated that pain, sleep, and depression could share some neurobiological matrix. Anxiety, mood changes, and depressive symptoms are however a common feature in the sleep disturbed patient, chronic pain patient, and patient with comorbidly sleep-pain-related complaints. Therefore, in patients with these complaints, it is important to adequately address

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Polysomnography is the gold standard for sleep evaluation if movement disorders during sleep or parasomnias are suspected. In the case of disorders of central hypersomnolence, a Multiple Sleep Latency Test should be made after a PSG night in order to properly diagnose. Although PSG remains the gold option also to diagnose sleep disordered breathing, several simplified sleep studies are accepted and available. The American Academy of Sleep Medicine however recommends that PSG or home sleep apnea testing be used for diagnosis of uncomplicated adult patients presenting with signs and symptoms that indicate an increased risk of moderate to severe OSA. Important to note is that if a single home testing for sleep apnea is negative, inconclusive, or technically inadequate, PSG should always be performed for diagnosis in OSA. Furthermore, if a first PSG is negative and clinical suspicion for OSA remains, a second PSG should be considered [70].
