Chapter 77 Insomnia
Diagnosis, Assessment, and Outcomes
The evaluation of insomnia should take place within two general frameworks: The one is the 3P model that classifies case material into predisposing, precipitating, and perpetuating factors, and the other is the context of the insomnia, considering stage of development, social situation, and culture. The sleep history can be facilitated by the use of a formatted questionnaire that systematically surveys key issues. A sleep diary filled out each day is one of the most useful ways to evaluate the problem and track the effect of interventions. The use of polysomnography and actigraphy are not routinely recommended.
A dual approach to assessment is suggested that uses a wide lens to establish the broad thematic structure of the problem (e.g., what part of the night is disturbed, daytime activities that affect sleep, thoughts about sleep, worries about the daytime functional deficits, sleep–wake habits). The other approach is pointedly personal and uses a focused lens that dissects a particular night of insomnia—and the subsequent day—to catch the weave of events and mental responses that locate the targets for treatment within the vicious cycle created by the interaction between poor sleep and psychological reactions.
Attention needs to be paid in the evaluation to comorbid conditions such as psychiatric, sleep and medical disorders. Consistent with the consensus of the field it is assumed that these disorders can trigger, contribute to, or be unrelated to the insomnia.
The goal of this chapter is to provide a comprehensive overview of the diagnosis of insomnia, the clinical assessment of insomnia, and the measurement of outcome and to provide a guide as to how to select from the growing array of assessment tools available. The focus is on the adult insomnia patient. The full assessment described here takes between 60 and 120 minutes, depending on the complexity of the patient’s insomnia. Given that many professionals needing to assess insomnia are time pressed, a quick assessment guide is included as Box 77-1. The information within Box 77-1 is elaborated in the text and can be used as a checklist or guide for the broad domains that should be covered during an assessment.
Box 77-1 Quick Assessment Guide
Insomnia is an ongoing difficulty getting to sleep, staying asleep, waking up too early, or waking up and feeling that the sleep obtained is not restorative. In addition to the sleep complaint, the person with insomnia reports daytime impairment and has an adequate opportunity for sleep.1 Three classification systems offer specific diagnostic criteria for insomnia. The Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revision (DSM-IV-TR)2 and the International Classification of Diseases, 10th revision (ICD-10),3 offer a small number of broad categories based on current symptoms and functioning, but the International Classification of Sleep Disorders, second version (ICSD-2),4 offers a larger number of subtypes that require the assessor to make judgments about the causes of the insomnia. Table 77-1 lists the key features of the ICSD-2 diagnoses, and Table 77-2 summarizes the diagnostic codes of the ICSD-2 and the DSM-IV-TR. Research is needed to determine the validity and reproducibility of both the broad categories and the subtypes.
|INSOMNIA DIAGNOSIS||KEY FEATURES|
|307.41 Adjustment sleep disorder||Associated with a specific stressor|
|307.42 Psychophysiologic insomnia||Heightened arousal and learned sleep-preventing associations|
|307.42 Paradoxical insomnia||Subjective report of severe sleeplessness not congruent with the absence or minor degree of daytime impairment|
|327.02 Insomnia due to a mental disorder||Associated with mental disorder, but the insomnia constitutes a distinct complaint|
|307.42 Idiopathic insomnia||Onset in infancy or early childhood|
|V69.4 Inadequate sleep hygiene||Associated with activities that are inconsistent with optimal sleep|
|V69.5 Behavioral insomnia of childhood||The result of inappropriate sleep associations or inadequate limit setting|
|292.85 Insomnia due to a drug or substance||Disruption to sleep due to a drug or substance (prescribed, over-the-counter, or recreational)|
|327.01 Insomnia due to a medical condition||Associated with a coexisting medical disorder or other physical issue|
|780.52 Insomnia not due to a substance or physiologic condition, unspecified||Unable to be classified elsewhere but suspected to be associated with a mental disorder, psychological factor, or sleep-disruptive practice|
|327.00 Physiologic (organic) insomnia, unspecified||Unable to be classified elsewhere but suspected to be associated with a medical disorder, physiologic state, or substance|
|ICSD-2* INSOMNIA CATEGORIES||DSM-IV-TR† INSOMNIA CATEGORIES|
|307.41 Adjustment sleep disorder||307.42 Primary insomnia|
|307.42 Psychophysiologic insomnia||307.42 Primary insomnia|
|307.42 Paradoxical insomnia||307.42 Primary insomnia|
|307.42 Idiopathic insomnia||307.42 Primary insomnia|
|327.02‡ Insomnia due to a mental disorder||307.42 Insomnia related to another mental disorder|
|V69.4 Inadequate sleep hygiene|
|V69.5 Behavioral insomnia of childhood|
|292.85 Insomnia due to a drug or substance||292.89 Substance-induced sleep disorder, insomnia type|
|327.01‡ Insomnia due to a medical condition|
|780.52 Other insomnia not due to a substance or physiological condition, unspecified|
|327.00 Organic insomnia, unspecified|
‡ Code the primary condition first and the insomnia second (e.g., dysthymic disorder, 300.4, Insomnia due to a mental disorder, 327.02). Alternatively, one of the following codes may be used: ICD-10 Insomnia Categories,3 F51.0 Nonorganic sleep disorders, G47.0 Organic sleep disorders.
The Duke Structured Interview for Sleep Disorders (DSISD) is a structured series of questions that helps the clinician to efficiently establish DSM-IV-TR, ICSD-2, and research diagnostic criteria (RDC) insomnia diagnoses. Each section of the interview starts with a screening question. If this is endorsed, a series of follow-up questions are asked. If the screen is not endorsed the follow-up questions are skipped and the assessor moves to the screening question in the next category. The DSISD is divided into three sections: insomnia diagnoses, other sleep disorders (e.g., dyssomnia), and sleep disorders associated with excessive daytime sleepiness. The DSISD has been found to be effective for identifying those meeting criteria for an insomnia disorder.5
Note that insomnia symptoms are a feature of a range of other sleep disorders. For example, insomnia is listed as a feature of various sleep-related breathing disorders, circadian rhythm disorders, sleep-related movement disorders, and the parasomnias (e.g., nightmare disorder and sleep-related breathing disorder). Such symptoms can arise, at least in part, from the precipitating factors that are also a feature of the insomnia disorders (e.g., hyperarousal, conditioning).
Recommendations for the standard research assessment of insomnia have been published.6 This was the result of a detailed review of the literature and an expert consensus process involving an evidence-based quantitative review of the available methods. Table 77-3 summarizes the measures selected by this process. Although these are recommendations for research contexts, they serve as a useful guide for clinicians to select from the vast array of instruments available.