The analysis carried out here to assess the pharmacological treatment and health status of people with insomnia in Germany shows that with a median duration of illness of 5 years, around 50% of those affected suffered from moderate to severe insomnia and only 30% of those affected took a prescription medication to treat their insomnia or had even been offered this at all. The state of health, self-reported morbidity, and quality of life were described as limited by those affected by insomnia.

The data of the NHWS 2020 participants from Germany included in this study are based on non-verified self-reports. The focus was on people who stated in the survey that they had been diagnosed with insomnia by a physician. This was around 5% of the total respondents, which is roughly in line with previous data on the prevalence of insomnia in Germany [21, 29]. The participants with insomnia had been suffering from their condition for several years and, therefore, their condition can be interpreted as chronic insomnia [1, 24]. The duration of the illness coincides with the often long waiting time until first consultation with a specialist [13]. The proportion of adults suffering from insomnia with at least moderate insomnia according to the ISI [10] was around 50%. However, it is not possible to determine with certainty from the available data how many participants had acute insomnia vs. chronic insomnia [1, 5, 24]. Current estimates based on the best available evidence assume approximately 8332–219,413 people with chronic insomnia in Germany [15, 23]. The wide range of estimates is due to the fact that the data sources are difficult to objectify. Only figures from coding databases can be used as a basis for these estimates, in this specific case, data from SHI-insured persons. At present, only ICD-10-GM F51.0 can be used for coding [5]. F51.0 is currently the only ICD-10-GM code that also reflects a chronic form of insomnia [5]. In addition, reports of incapacity to work in people with any form of insomnia were used for these calculations [15, 23, 27]. However, due to the vagueness of previous coding and the use of indirect indicators, it can be assumed that the number of people with chronic insomnia requiring treatment has socioeconomic relevance.

According to the literature, around 30% of people with insomnia are treated with medication [15, 23]. These figures are confirmed by the data presented here. Overall, between 2,000 and 79,000 people with chronic insomnia are currently being treated with medication in Germany [15].

According to current data, around 50% of people with insomnia also suffer from comorbidities. Chronic insomnia, which can occur comorbidly with depression, for example, is currently not represented at all in ICD-10 [5]. This shortcoming will be rectified in ICD-11, which has been effective internationally since 1 January 2022 [5]. In ICD-11, chronic insomnia is coded in its own chapter of sleep–wake disorders under 7A00 [5], thus considering chronic insomnia as an independent disorder in its own right.

The data collected also allow the conclusion to be drawn that the health status and quality of life of people with sleep disorders in Germany is impaired compared to the general population, which has also been published in earlier studies [21]. While the summarized values of the physical (for self-reported morbidities) and mental (for quality of life) sum components of the SF-36 for all 10,034 NHWS participants correspond to the German reference values of 50 each [11], these values are lower for the German insomnia cohort as a whole at approximately 44 (for self-reported morbidity) and 41 (for quality of life) [11]. This indicates considerable physical and psychosocial impairments and suggests a need for action in the management of insomnia.

In both cohorts, over 50% of the insomnia diagnoses were made in the area of general and internal medicine. However, the difference in the type of medical specialty that diagnosed the “sleep disorder” is statistically significant between the DT cohort and the DUt cohort (chi2 = 13.9140; p = 0.0030; Table 4). In the DT cohort, psychiatric specialists diagnosed the sleep disorder about twice as often as in the DUt cohort. Even if it is not known whether the medical discipline making the diagnosis is also the prescribing discipline, one reason for this could be the restriction on the prescription of hypnotics in accordance with No. 32 Annex III of the German Medicines Directive (AM-RL). Since the aim of the AM-RL is to prevent medicalization, the data support the weight of this guideline. However, diagnoses by different medical specialties must be comparable in terms of assessment and knowledge of the condition. As the field of sleep medicine is interdisciplinary, the training requirements for the diagnosis and treatment of people with sleep disorders should be the same across all medical specialties. At present, they vary enormously, which is why there are currently large gaps in medical knowledge and associated gaps in health care. Only with an additional specialist qualification in sleep medicine can a consistent approach be assumed. There is a need for inclusion of sleep medicine curricula in the training of some specialties and the general inclusion of comparable sleep medicine content, including insomnia, in teaching. As far as sleep medicine care is concerned, more interdisciplinary sleep outpatient clinics specializing in insomnia and the implementation of guideline-based specific treatment pathways for the individualized management of chronic insomnia are needed [3, 29].

Interestingly, more than 70% (394/532) of people with insomnia stated that they did not take any prescription medication despite their symptoms, and for the most part had never even been offered this by their physician. This may be due to the fact that the primarily recommended and available benzodiazepines and Z‑drugs are only authorized as short-term therapy. They should therefore generally only be prescribed for up to 4 weeks, including the tapering phase, and may also be a reason for medical reluctance in prescribing due to their potential for dependency or loss of efficacy. In addition, there is often skepticism on the part of both the prescribing specialists and the patients towards potentially addictive medications, which prevents them from being prescribed. As only prescribed medications were surveyed, it is not possible to make any statements about other treatment options, including behavioral therapy interventions or the use of over-the-counter medicines. It is known from the literature that currently only around 10% of sufferers receive conventional structured CBT‑I [23, 27]. Individual components of behavioral therapy such as sleep hygiene or relaxation techniques are used more frequently, but there are no scientific data on this. Digital health applications (DiGA) are now regularly available in the SHI system for the treatment of insomnia [16], which open up new possibilities in the structured support of people with sleep disorders, but no data are yet available on their effectiveness in everyday care.

The participants in the two analyzed cohorts were around 50 years old on average and the majority were female. This gender and age distribution is in line with other studies [27, 29]. The data show that people with insomnia in Germany appear to be socially disadvantaged. The proportion of SHI overage vs. private insurance in the insomnia cohorts was also significantly higher than among all German NHWS participants, although the distribution among all NHWS participants corresponded to that of the general population. Compared to the overall respondents (at least one comorbidity at 20.1%), the proportion with at least one comorbidity was twice as high in both insomnia cohorts (DT, 39.1%; DUt, 38.3%). The most frequently reported comorbidities of insomnia were pain (DT, 65.2%; DUt, 68.5%), followed by depression (DT, 55.8%; DUt, 49.2%). The high proportion of people in the insomnia cohorts with a reported anxiety disorder is striking. The data are also significant in terms of the comparison of insomnia cohorts vs. non-insomnia cohorts. Although it is not possible to say to what extent impairments in everyday life can also be attributed to the comorbidities, the data suggest that sleep disorders can be associated with various other health disorders and can have a bidirectional relationship [14].

Overall, at the time of the survey, only around 30% of adults with insomnia reported that they were receiving prescription medication (= DT cohort), mostly in the form of non-B/non‑Z or off-label medications. The reasons for the high proportion of non-B/non‑Z or off-label prescriptions cannot be determined from the self-reported data. Of those treated with medication, around 50% state that the severity of their sleep disorders and the effect on their daily wellbeing are significantly higher if they do not take medication. This could also be the reason why it is precisely these sufferers in the DT cohort who receive medication at all. However, the data suggest that the duration of treatment in the DT cohort is more than 40 months for B and Z‑drugs, which significantly exceeds the recommended prescription period. The literature describes that people with insomnia also resort to private prescriptions [4, 9, 19, 27]. Those affected also have their medication prescribed by several medical specialists in succession [27]. This could suggest a high level of suffering on the part of those affected and restricted prescribing on the part of the treating physicians, or it could be a sign of high consumption due to addiction and dependence. This finding is in line with the German government’s addiction report [9]. A recently published study confirms the prescribing behavior of physicians, as there was an increase in private prescriptions for benzodiazepines and Z‑drugs among those insured by statutory health insurance (SHI) in Germany between 2014 and 2020, with SHI prescriptions falling [19]. According to the current guideline on drug dependence published by the Drug Commission of the German Medical Association, benzodiazepines and Z‑drugs are the leading substances for drug dependence [4]. These findings support the statement regarding massive underuse and misuse, particularly in chronic insomnia, and reflect a high need for new innovative, inclusive pharmacological treatment options.

Symptoms of insomnia affect health as well as mental and physical performance and thus also impair labor productivity [18, 27]. This is also shown in the present analysis. Estimated EQ-5D standard values for the total population in Germany show that approximately 60% have a value of 0.92, which corresponds to the statement “no problem” for all items surveyed [25]. The health status of the overall German NHWS respondents was better than that of the people with insomnia: with a mean value of 0.88 for the EQ-5D-5L index value, the overall respondents were in the upper range. For both insomnia cohorts—with values of 0.73 (DT) and 0.76 (DUt)—there were relevant effects [25] of insomnia on the state of health. In contrast to the overall respondents, respondents in both cohorts stated on average two to three times more frequently that they were absent from work. The small differences in the cohorts could be due to the influence of insomnia on health status as measured by EQ-5D.

Overall, the care situation with regard to differential diagnosis and treatment appears to be inadequate and leads to long periods of illness. The question is how healthcare services can be adapted in future and how the availability of targeted treatment options can be improved.