Differences between patients' and clinicians' report of sleep disturbance: a field study in mental health care in Norway

Sleep disturbance is likely to be a core feature across several mental disorders [1, 2]. In patients with depression, sleep disturbance predicts poorer treatment outcome and is associated with more suicide attempts [3, 4]. Moreover, 40%-70% of patients successfully treated for depression still experience sleep disturbance after treatment [3, 5], and these patients may be at a higher risk of relapses into new episodes [6]. This challenges the assumption that the sleep disturbance will also be improved once the primary mental disorder is treated. It may be more adequate to assume that there is a need for specific treatment for sleep disturbance for these patients.

Adequate management of insomnia starts with recognition and diagnostic assessment. There is a risk, however, that insomnia could become trivialized in mental health care because it is both a diagnosis as well as a symptom of several mental disorders. But although many may share the impression that insomnia is under-recognized by clinicians [7, 8], the actual data available from medical practice is limited and ambiguous. Two studies have confirmed that sleep is seldom documented in medical charts in general hospitals [9] or on general medical services [10], whereas a recent large-scale study concluded that sleep disturbance is adequately recognized by general practitioners [11]. Only one study has been conducted to test if sleep disturbance is clinically recognized in patients with mental disorders [12]. The authors found that 80 of 100 patients on a psychiatric consultation service had sleep disorders but disturbed sleep was not mentioned in the records of 54% of these patients. However, the study was conducted in the early 1980s and had limited external validity. The state of sleep in psychiatry might be different 30 years later. Thus, even though 50% to 80% of patients with mental disorders have sleep disturbance [13], there is currently limited empirical knowledge about diagnostic assessment, clinical recognition and treatment for this large group of patients.

As the DSM and the ICD will be revised during the next years there is currently a need for data that can inform this revision process [14]. The primary users of these diagnostic systems are mental health care personnel and general medical clinicians and the classifications should therefore be meaningful for these groups [14]. A basic test of clinical utility is to explore whether clinicians in mental health care use the insomnia diagnosis. However, because insomnia is also a symptom of several mental disorders, there is a possibility that clinicians could recognize and treat sleep disturbance without diagnosing it.

The aims of this study were therefore to examine whether insomnia is diagnosed and whether sleep disturbance is recognized and treated in patients with mental disorders. We used three large, cross sectional, multicenter data-sets for this purpose.

Data-set 1 included demographic information and clinical diagnostic codes from an estimated 93% of all patients receiving treatment in mental health care, both private practice and public health care, in Norway during two weeks in 2008.

In addition to demographic and clinical diagnostic assessments, data-sets 2 and 3 also included both clinicians' and patients' report of sleep disturbance and prescriptions of hypnotic medication. Data-sets 2 and 3 were conducted at eight public mental health centers during eight weeks in 2002 and four weeks in 2005, respectively. The centers were selected to be representative for the country as a whole and the catchment areas covered about 10% of the Norwegian population. The centers covered both rural and urban areas as well as northern and southern parts of the country. The data collections were commissioned by the Norwegian Department of Health to evaluate the state of the National Mental Health Care System and were not designed specifically to evaluate sleep disturbance in patients with mental disorders.

Data-sets 1, 2 and 3 were used to assess the prevalence of clinically diagnosed insomnia. Data-sets 2 and 3 were also used to assess the agreement between clinician and patient reported sleep disturbance and prescription of hypnotic medication. The analyses were replicated in the data-sets to test the reliability of the findings.

Using three independent and nationally representative data-sets, we found that the diagnosis of insomnia was virtually non-existent in patients with mental disorders. Only 34 of 42507 patients had a diagnosis of insomnia as either a primary or a comorbid diagnosis. However, about 40% of all patients experienced severe sleep disturbance and at least 22% reported this to be one of their most prominent problems. Although they did not diagnose it, clinicians indicated that 24% of their patients had sleep disturbance as a prominent problem. We found a notable discrepancy between the clinicians' report and the patients' report of sleep disturbance. The patients and clinicians agreed in less than 30% of the cases where either the patients or clinicians had reported sleep disturbance. The probability of the patients themselves experiencing sleep disturbance when the clinician reported this, was less than 62%. This probability was surprisingly even lower when the patient experienced their sleep disturbance to be one of their most prominent symptoms, with a predictive value of less than 37%. Thus, the precision of clinician-rated sleep disturbance was close-to-chance when compared to the patient report. Of the patients who used hypnotics, 55% reported having sleep disturbance whereas 23% had neither clinician nor patient reported sleep disturbance. These findings were replicated with only minor differences in the different samples.

The diagnostic findings are at odds with findings from epidemiological studies where the prevalence has been reported to be about 100 times higher [18‐20]. However, our findings are in line with two previous studies where large discrepancies between findings from epidemiological studies and diagnostic practice in clinical settings have been reported [21, 22]. Although the diagnostic recommendation in the ICD-10 is to code insomnia as a comorbid disorder if it is one of the most prominent symptoms, our findings indicate that clinicians are reluctant to use these recommendations.

Underlying this may be a long-standing issue of whether insomnia should be regarded as a symptom of other disorders or as a disorder in it self. Clinicians may not find it relevant to code insomnia as a comorbid condition as they regard it as a part of the primary mental disorder. If clinicians do not find the diagnosis of insomnia relevant to their practice, this may raise concerns about the usefulness of the diagnosis in its current form. In this respect it is interesting to note that the online draft of the DSM-5 proposes to remove the diagnosis of Insomnia Related to Another Mental Disturbance and only operate with the diagnosis of Insomnia. The proposed change in the DSM reflects a change in paradigm from thinking of insomnia as a symptom to thinking of insomnia as a disorder. It recommends coding Insomnia Disorder if the criteria are fulfilled regardless of meeting criteria for other mental disorders, because determining the cause or consequence of the problem is clinically difficult, if not impossible [23].

Patient report of sleep disturbance was higher than what is found in the general population using similar measures [19], but in agreement with other studies from patients with mental disorders [13]. Hypnotic medication was, relative to previous studies [24, 25], seldom prescribed to the patients in the current study. Less than 9% of all patients were prescribed such medication compared to 7% of the general population in Norway in the same period [20]. Patients with mental disorders are likely to be prescribed other medications that have effects on sleep, such as some anti-depressants or anti-psychotic medication that could make hypnotic medication less needed. Still, it is curious that at least 23% of the patients who were prescribed hypnotic medication had neither self-reported nor clinician-reported sleep disturbance. This could indicate that patients who are being prescribed hypnotics stay on hypnotics after the sleep disturbance has been treated.

The low recognition of sleep disturbance raises questions concerning education and training of health care professionals. Although a call for improved education about sleep was made in the 1980s when similar findings were reported [12], the situation does not seem to have improved. Physician training in the recognition of sleep specific symptoms has been reported to be minimal [26]. Similarly, a survey of 212 directors of graduate and internship programs of clinical psychology revealed that only 6% of the programs offered courses in sleep and most reported that their institution was ineffective in providing sleep education [27]. Moreover, doctors seldom ask about sleep in clinical interviews [28], and patients with sleep disturbance infrequently report this to their clinicians [29, 30]. This makes it important for health care professionals to have knowledge about the features of sleep.

When patients meet the criteria for a mental disorder, insomnia is almost never diagnosed, and sleep disturbance is imprecisely recognized relative to the patients' experience of sleep disturbance.

Our results, rather than taken as criticism of individual health care professionals, should be interpreted as a call for improved teaching and better understanding of sleep disturbance and its treatment. Moreover, the non-existence of the insomnia diagnosis in three different clinical samples may not only be a result of insufficient training, but also indicate an area where revising the ICD and DSM systems could be useful. The suggested change in the DSM-5 of coding insomnia is likely to be favorable compared to the current system and could be considered also in the ICD-11.

The authors declare that they have no competing interests.