In this study, patient characteristics, sociodemographic factors and pharmacological treatment strategies in inpatients with BPD over two intervals, 1996–2004 and 2008–2012, respectively, were compared.

Patient characteristics and sociodemographic characteristics

One interesting finding of this study was the higher proportion of female inpatients between 2008 and 2012 (86.2%) compared to the cohort of the previous treatment period. Moreover, chronic feelings of emptiness and identity disturbances were very frequent symptoms found in both cohorts and were significantly more frequent among BPD inpatients treated between 2008 and 2012. With respect to BPD inpatients of the interval 2008–2012 the four most frequent reasons for admission were affective symptoms, parasuicidal tendencies, suicidality and anxiety disorder. Additionally, sociodemographic data gained some surprising results which have not been reported, previously. Overall social isolation appeared to have increased over time with fewer patients living in partnerships or being married. On the other hand, an increase of frequent partner changes was reported. These changes could also be found in the documentations of BPD diagnostic criteria. BPD inpatients of the interval 2008–2012 had more often unstable relationships and showed more often quarrelsome behavior compared to the inpatients of the previous cohort. Therefore, the social adaptation level seems to have worsened. Also, fewer patients had a high school degree which is in accordance to Gescher et al. [14]. In our study, the proportions of unemployment were generally high among BPD inpatients (32.9–45.7%). Gescher et al. previously reported similar data on the occupations of BPD patients treated between 2005 and 2009 (44%) confirming the low level of social functioning of BPD patients [14].

Comorbidities

79.3% of the BPD inpatients treated between 2008 and 2012 suffered from at least one additional psychiatric disorder and almost one third from three or more comorbid psychiatric disorders. In this study, a significantly decrease of substance-related disorders was found (79% vs. 55%) and fewer patients were addicted to sedatives or hypnotics in 2008–2012 compared to 1996–2004. Additionally, fewer patients had an adjustment and somatoform disorder (61% vs. 40%), eating disorder (34% vs. 14%) and other personality disorders (26% vs. 6%) respectively. Zanarini et al. and Grant et al. reported similar comorbid conditions considering the substance-related disorders. They found 64.1 and 50.7% BPD patients with substance use disorders respectively [15, 16]. Interestingly, the proportion of comorbid eating disorders in this study were lower compared to the one reported by Zanarini et al. (53.0%) [15].

Pharmacotherapy in BPD

We reported a significant increase of drug use in 2008–2012 compared to a previous cohort treated between 1996 and 2004. Almost every BPD inpatients received at least one psychotropic drug at time of discharge. Considering all medicated inpatients, the mean number of medications was 1.86 (58 medicated inpatients) at time of admission and 1.54 (82 medicated inpatients) at time of discharge, respectively. Our results stand in line with previous findings by Knappich et al. reporting results of a survey among psychiatrists in private practices in Germany investigating their prescription strategies with regard to BPD patients and they found that the overall rate of psychotropic drug therapy was 94% [17]. Data from the European Drug Safety Project AMSP revealed that 90% received at least one medication [18]. The high prevalence of psychopharmacotherapy is also true for other European countries (92% in the UK) [19] and the United States [20].

Antidepressants

Compared to the later period 1996–2004, fewer subjects received TCAs or tetracyclic antidepressants and treatment with MAO inhibitors was completely abandoned, maybe due to the better tolerability of SSRIs and atypical antidepressants but also because of the toxicity of TCA when overdosed, i.e. during a suicide attempt. In our study, SSRIs were the leading antidepressants. Also, Bridler et al. published that about 70% of the BPD patients received antidepressants, predominantly SSRIs (39.2%) [18]. Actually, SSRI showed positive effects in terms of alleviating affective and maybe impulsive symptoms too [21] and sertraline could be superior to olanzapine in terms of treating depressive symptoms [22]. Stoffers and Lieb reviewed pharmacological RCTs up to August 2015 and they found neither statistically nor clinically significant efficacy for any SSRIs [23]. They also considered previous Cochrane Collaborations reviews [8, 9] and concluded that recommendations by the APA 2001 guideline with respect to SSRIs are no more valid. Instead, SSRIs should be used to treat major depressive disorders or if “another comorbid condition required” antidepressants [9].

Antipsychotics

The prescription rate of second-generation antipsychotics among all inpatients receiving antipsychotics was higher in 2008–2012, but that was not significantly so compared to 1996–2004. The use of lower-potency antipsychotics dropped significantly over the same time period (83% 1996–2004 versus 42.5% 2008–2012). Interestingly, we saw frequent usage of the atypical antipsychotic quetiapine (19.5%), which was in accordance with the findings of the AMSP study (mean 22% 2001–2011 and 33% 2009–2011), followed by aripiprazole (4.7%). This observation is conforming to available RCTs describing promising effects in terms of second-generation antipsychotics [21, 22], i.e. of quetiapine [24, 25], in some psychopathologies seen in BPD patients.

Mood stabilizers

Although there was kind of evidence on the use of mood stabilizers in the treatment of BPD patients [9, 23], more recent findings oppose these former recommendations [26]. Indeed, we found a low overall prescription rate of mood stabilizers in our sample. In contrast, Bridler et al. showed threefold higher prescription rates in terms of anticonvulsants (31.5%) [18]. However, the reason for that was a lower prescription rate of carbamazepine compared to the period 1996–2004, which was initially about 20%. Only 3.4% of the inpatients with BPD received carbamazepine between 2008 and 2012. One reason for that could be the rising awareness for its troublesome pharmacological interactions. Instead, lamotrigine was used in our clinic during the last observation period. It would be of great interest if the recent findings towards the effectiveness of lamotrigine will have a significant impact on the prescription behavior.

Sedatives

The use of benzodiazepines among BPD inpatients is still high (24.1% at discharge). With exception of short-term use this class of drugs should be considered to be obsolete because of the addictive potential [27]. Furthermore, alprazolam seems to increase suicidal tendencies and aggressive behaviors [28]. However, some patients may have been discharged with a benzodiazepine prescription because these patients were already taking these drugs at admission and could not been withdrawn abruptly. The attitude of psychiatrists towards hypnotics/benzodiazepines was investigated by Knappich et al. revealing that 71.4% of them announced to prescribe benzodiazepines, most often lorazepam, in BPD outpatients [17].

Opioid antagonists

The use of naltrexone increased compared to the interval 1996–2004. Dysregulations of the endogenous opioid system seems to be crucial for the pathogenesis of BPD [29]. According to this theory, opioid antagonist treatment can have acute and long-term effects. Acutely, naltrexone can block the rewarding effects of harmful BPD behaviours, e.g. self-injury, Chronically, naltrexone may increase number and sensitivity of μ-opioid receptors which appear to be lowered in BPD. Although there are few controlled studies with opioid antagonists for the treatment of BPD, many studies have shown the efficacy of the opioid antagonists naltrexone and nalmefene in symptoms that are often associated with BPD, including self-harming behaviors [30,31,32], heroin [33], amphetamine [34] and alcohol addiction [35,36,37], pathological gambling [38, 39] and anorexia/bulimia nervosa [40]. Furthermore, an open label study showed reduction of dissociative symptoms in BPD females [41]. This finding could not be confirmed by a small cross-over placebo controlled study, perhaps due to the low power of the study [42]. Additionally, another RCT evaluating nalmefene in patients with BPD with comorbid alcohol abuse showed a significant reduction in heavy drinking days and a reduction in a BPD symptom list and CGI-BPD [43]. Nevertheless, the efficacy of naltrexone and other opioids antagonists needs to be investigated further.

Limitations of the study

One limitation is the retrospective study design and the lack of matched controls. Furthermore, informations about the efficacy of the psychotropic drugs were not available. It is of note that our investigation focused on an inpatient university department and mainly on acute crisis interventions. Therefore, the results presented in this study are not necessarily representative for the entire population. However, in a comparison of our acute psychiatric department with our neighbor department for psychotherapy, our workgroup showed that the extent of usage of psychotropic drugs did not significantly differ between these two departments (unpublished data).