Use and abuse of benzodiazepines are difficult to evaluate in psychiatric acute admissions. Patients present in severe crisis often complicated by behavioral problems, substance use, and multiple axis 1 diagnoses [1]. In these clinical settings benzodiazepines are regarded as first line nonspecific treatment in patients suffering from acute agitated and psychotic conditions without known cause [2], and specific treatment in patients suffering from acute catatonia [3]. In patients suffering from severe agitation and substance abuse, benzodiazepines may also be regarded as first line acute treatment [4]. A substantial number of other patients suffering from psychoses or major depressive disorders use benzodiazepines as adjuvant symptomatic treatment to antipsychotics, mood stabilizers or antidepressants [2, 5, 6]. Patients with depression may however receive benzodiazepines for years without being treated with antidepressants [7–9].

Medication with benzodiazepines may have short and long time negative consequences. Frequently patients are admitted to psychiatric acute departments due to abstinence, intoxication, delirium and seizures [10]. Benzodiazepines are also abused in combination with illegal substances. Such abuse as part of a major psychiatric disorder is probably frequent [7].

Benzodiazepine use has been found in 40 to 45% of patients admitted to psychiatric hospitals [11–15], and being female and old increase the use of benzodiazepines [16, 17]. Studies of illegal use of benzodiazepines in acute psychiatric admissions are few and the authors found no studies comparing legal and illegal use at admittance.

The aims of the present study were to assess the frequency of use of legal and illegal benzodiazepines at admissions to an acute psychiatric department and to compare patients using legal, illegal and no benzodiazepines.

In the study period 184 patients with 227 admissions were included. Mean age was 39.5 years (SD 15.5 years). There were 95 women with 122 admissions and 89 men with 105 admissions.

In 65 of 104 (62.5%) admissions with psychoses or major affective disorders (ICD-10 F 20.00 - 39.99), the patients received adequate medication with antipsychotics, antidepressants or mood stabilizers before admission. Among the 65 patients receiving adequate medication, 34 (52%) used benzodiazepines while among the 39 patients that did not receive adequate medication 11 (28%) used benzodiazepines. (χ² = 5.77, df = 1, p = 0.016).

Legal users had a higher number of prescribed psychotropic medications not including benzodiazepines than no users (Table 1). Patients with psychoses or major affective disorders (ICD-10 F 20.00-39.00) treated with adequate medication, received a higher number of psychotropic medications not including benzodiazepines than patients without adequate medication (mean 1.91 (SD 0.861) vs. 0.33 (SD 0.621), p < 0.001) (Mann-Whitney U Test).

Urine samples were given in 196 of 227 admissions (86%). The results are summarized in Table 2. The correlations between verbal reports of the patients and urine analyses are published previously [13]. In the benzodiazepine group 4 patients (3%) had denied use but tested positive.

Average score for GAF for all admissions was 38.2 for symptoms and 39.0 for function, with no differences between legal, illegal and no users of benzodiazepines.

Legal use increased with age (Linear-by-linear association test, P < 0.001), and 80% of patients 65 years and older used benzodiazepines at admittance. Illegal use was most frequent in young patients (Linear-by-linear association test, P = 0.047) (Figure 1).

A somatic disease had been diagnosed in 73 admissions (32%). These were diseases of the nervous system (ICD-10 G00-G99) in 28 admissions, diseases of the circulatory system (I00-I99) in 25, diseases of the endocrine and metabolic system (E00-E90) in 17, diseases of the digestive system (K00-K93) in 6, diseases of the respiratory system (J00-J99) in 5 and various diseases in 18 admissions.

Patients admitted to psychiatric acute departments using benzodiazepines could be divided in two main groups. Illegal users were young, reported use of multiple illegal substances and were regarded as clinically affected by substances at admittance by the doctor on duty. Legal users were older, did not use multiple substances and were not regarded as clinically affected by substances at admittance. Among the illegal users, more than one benzodiazepine was frequent and the patients often had a substance use disorder. The findings at admittance were supported by the results from the laboratory tests.

In 62.5% of admissions with psychoses or major affective disorders the patients had received adequate medications before admission. Adequate medications were combined with benzodiazepines in 34 of 65 admissions while only 11 of 39 patients without adequate medication prior to admission received benzodiazepines. This indicates that patients with psychoses or affective disorders in risk of being admitted to psychiatric emergency departments are treated with benzodiazepines to relieve acute symptoms as long as the patients display symptoms sufficient for their psychiatric conditions to be diagnosed [2].

The major clinical challenge emerging from the present study is the relatively large population not receiving neither specific nor nonspecific pharmacological treatments before admission. This indicates that many acute major psychiatric episodes were neither recognized nor diagnosed before the acute emergency situation brought the patients to the acute department.

The use of antidepressants was lower among no users than among legal users of benzodiazepines (Table 1). We can not exclude the possibility that antidepressants induce adverse symptoms as agitation in sensitive individuals leading to more use of benzodiazepines [23, 24]. Agitation is common in severe depression (40 - 70%) [23] and is a frequent cause of admittance to psychiatric emergency facilities [25]. Benzodiazepines are effective and safe in the treatment of agitation [26]. Our data therefore supports that use of benzodiazepines in our present acute population could be clinically well-funded.

The doctors were able by the clinical examination at admittance to indicate which patients were abusing benzodiazepines, and which patients were using benzodiazepines as a nonspecific, specific or adjuvant medication as part of the treatment of a major psychiatric disorder. The legal users were less often regarded as intoxicated than the illegal users. When using benzodiazepines as adjuvant treatment for major psychiatric disorders the need for such treatment would decline as specific treatment with antipsychotics, antidepressants or mood stabilizers have effect on the main disorder. The probability of long time negative consequences of using benzodiazepines as part of an addiction habit is less among the legal than the illegal users.

This study has limitations. "Doctor's evaluations" reflects the opinion of the experienced clinicians. We do not have data on how many patients have long-term use of benzodiazepines.

The present study is strengthened by the prospective design. All patients from a defined catchment area in need of acute psychiatric services were included. Laboratory tests were taken shortly after admittance to the acute department.

The patients admitted to psychiatric acute departments using benzodiazepines can be divided in two main groups. Illegal users were young, used multiple illegal substances and were often evaluated as clinically affected by substances at admittance. Legal users were older, did not use illegal substances and were less frequently evaluated as clinically affected by substances at admittance. Benzodiazepines were often used as adjuvants to specific pharmacological treatment with antidepressants, antipsychotics or mood stabilizers for major psychiatric disorders.