Challenges in the Transition from In-Patient to Out-Patient Treatment in Depression
An Analysis of Administrative Health Care Data From a Large German Health Insurer
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Background: Few data are available on the characteristics of inpatient treatment and subsequent outpatient treatment for depression in Germany. In this study, we aimed to characterize the inpatient and outpatient treatment phases, to determine the rates of readmission and mortality, and to identify risk factors.
Methods: We carried out a descriptive statistical analysis of routine administrative data from a large health-insurance carrier (BARMER). All insurees aged 18 to 65 who were treated in 2015 as inpatients on a psychiatry and psychotherapy service or on a psychosomatic medicine and psychotherapy service with a main diagnosis of depression were included in the analysis. Risk factors for readmission and death were determined with the aid of mixed logistic regression.
Results: Of the 22 893 patients whose data were analyzed, 78% had been hospitalized on a psychiatry and psychotherapy service and 22% on a psychosomatic medicine and psychotherapy service. The median length of hospital stay was 42 days. Follow-up care in the outpatient setting failed to conform with the recommendations of the pertinent guidelines in 92% of the patients with a main diagnosis of severe depression during hospitalization, and in 50% of those with moderate depression. 21% of the patients were readmitted within a year. The mortality at one year was 961 per 100 000 individuals (adjusted for the age and sex structure of the German population), or 3.4 times the mortality of the population at large. In the regression model, more treatment units during hospitalization and subsequent treatment with psychotherapy were associated with a lower probability of readmission, while longer hospitalization with subsequent pharmacotherapy or psychotherapy was associated with lower mortality.
Conclusion: The recommendations of the national (German) S3 guidelines for the further care of patients who have been hospitalized for depression are inadequately implemented at present in the sectored structures of in- and outpatient care in the German health care system. This patient group has marked excess mortality.
Depression is one of the most common and most debilitating illnesses worldwide (1). It causes significant individual suffering (2) and is associated with increased mortality, due to suicide and comorbidities (3). In Germany, about three per cent of patients with depression are currently treated on an inpatient basis (4). After discharge from hospital, the risks of suicide (5, 6), recurrence and—if the patient does not achieve remission—chronification are increased (7, 8). To achieve complete remission or to prevent a chronic or recurrent course of the illness as well as suicide, the German National Disease Management Guideline (“S3 guideline”) recommends adequate follow-up care in the form of remission-stabilizing maintenance therapy. In patients with severe depression, treatment should consist of a combination of pharmacotherapy and psychotherapy. In patients with moderate depression, pharmacological or psychotherapeutic treatment alone, depending on the patient’s preference, is sufficient (9). These guideline recommendations are supported by the highest level of evidence (grade of recommendation “A”), i.e. they are based on multiple randomized controlled trials. Analyzes of routine health insurance data as well as surveys assessing the outpatient care of patients with depression found evidence of care deficits (4, 10, 11, 12, 13). Data on the characteristics of inpatient treatment of depression in Germany and the current state of follow-up outpatient treatment are scarce, making it difficult to assess the required health policy measures in the context of the current health policy debates about mental health care. Therefore, our study addresses—based on the routine data set of BARMER, a large German health insurer, covering more than 9 million persons in Germany—the following questions:
- How and for how long are patients with a depressive episode treated in a hospital/department of psychiatry and psychotherapy or a hospital/department of psychosomatic medicine and psychotherapy?
- Is the follow-up outpatient treatment guideline-adherent?
- What are the annual readmission and mortality rates and
- by which sociodemographic, illness-related or treatment-related variables are they influenced?
From the about 9.4 million persons insured with BARMER in 2015, those were selected who were between 18 and 65 years of age and discharged from psychiatric-psychotherapeutic or psychosomatic-psychotherapeutic inpatient treatment with an ICD-10 diagnosis of F32.x (major depressive disorder, single episode) or F33.x (major depressive disorder, recurrent). If the patient was discharged in 2015, the inpatient stay was regarded as an index stay. Subsequent to discharge, a 365-day observation interval was defined during which guideline-adherent follow-up treatment with medication and psychotherapy as well as readmission and mortality rates were assessed (short version, see eMethods).
Characteristics of the index population
22 893 of the approximately 9.4 million persons insured with BARMER (equaling a one-year prevalence of an inpatient stay of 0.25%) fulfilled the inclusion criteria (= index population). 66% (n = 15 059) were females. The age median was 47 years (range 47). 39% (n = 8991) of the index population were registered in a city (>100 000 inhabitants).
Characteristics of the index hospital treatment
The median length of inpatient stay was 42 days (minimum 1, maximum 816). At discharge from the index stay, 78% (n = 17 799) of the index population were treated in a hospital/department of psychiatry and psychotherapy and 22% (n = 5094) in a hospital/department of psychosomatic medicine and psychotherapy. Figure 1 and eTable 1 provide an overview of the distribution of cases (Figure 1a). What was striking was the small proportion of day-clinic treatment, especially in psychosomatic medicine (Figure 1b), and a significantly higher treatment density by physicians/psychologists in hospitals/departments of psychosomatic medicine and psychotherapy compared to hospitals/departments of psychiatry and psychotherapy, (Figure 1c), where, however, the vast majority of patients with severe or psychotic depression were treated (Figure 1d). With regard to secondary diagnoses, there were no major differences between the two types of hospitals/departments (Figure 1a).
Severity-adapted guideline-adherent follow-up treatment
With regard to the severity-adapted guideline recommendations, 92% (n = 12 395) of the patients with severe depression did not receive guideline-adherent follow-up treatment with a combination of pharmacotherapy and psychotherapy (Figure 2a). Of the patients with moderate depression, 50% (n = 4605) did not receive guideline-adherent follow-up treatment with either medication or psychotherapy (Figure 2b).
The analysis of outpatient pharmacotherapy found that 84% of the 13 427 patients with severe depression (F3X.2 or F3X.3) and 70% of the 9270 patients with moderate depression (F3X.1), filled at least one antidepressant prescription during the follow-up year. However, only 57% (n = 7651) and 42% (n = 3908) of the patients with moderate depression and severe depression, respectively, were given a prescription—as recommended in the guideline—during the first quarter after discharge and, where appropriate, follow-up prescriptions with defined daily doses (DDDs) sufficient for a period of at least four months For an overview of the DDDs of the prescribed substances see the eFigure.
For the outpatient follow-up treatment, it was found that only 33% (n = 4428) and 37% (n = 3474) of the patients with severe and moderate depression, respectively, received one hour of psychotherapy within the one-year observation interval at all. Only 12% (n = 1676) and 15% (n = 1376) of patients with severe and moderate depression, respectively, received the first hour of psychotherapy within the first quarter after discharge and at least eight hours of psychotherapy during the one-year observation interval, as recommended in the guideline.
The interval between discharge from hospital and the first hour of psychotherapy was assessed in the 4311 patients who had not received psychotherapy in the year prior to hospital admission. Among these patients, the median interval between discharge and start of psychotherapy was 111 days (95% confidence interval: [106; 115]). Psychotherapy was primarily individual therapy with cognitive behavioral therapy (55%) or psychodynamic psychotherapy (43%), whereas psychoanalysis and group therapy played only a marginal role (Table 1).
eTable 3 shows whether a specialist or general practitioner/internist was consulted during the first quarter of treatment in the observation interval.
During the observation interval, 21% (n = 4798) of the index population were readmitted to inpatient or day-patient psychiatric-psychotherapeutic or psychosomatic treatment, 5% (n = 1103) twice or more. To evaluate whether guideline-adherent follow-up treatment helps to prevent readmission, we looked for evidence of risk factors of readmission in the second half of the year after discharge, using a multi-level regression model. In the random intercept null model, hospital and region explained a substantial proportion of the variation with regard to readmission. In the three-level regression model, older age was a sociodemographic factor that increased the likelihood of readmission. With regard to disease-related factors, the primary diagnosis of severe depression and the secondary diagnoses of personality disorder, posttraumatic stress disorder, obsessive-compulsive disorder, addiction or alcohol-related disorders significantly increased the likelihood of readmission in the model. With regard to treatment-related factors, the likelihood of readmission increased with treatment in a hospital/department of psychiatry and psychotherapy as well as with guideline-adherent follow-up treatment with antidepressants. In contrast, more treatment units during index treatment and guideline-adherent psychotherapeutic follow-up treatment decreased the likelihood of readmission. McFadden’s Pseudo R2 was 0.03; the predictors thus explained a moderate proportion of the variation beyond the hospital-related and regional variation (14) (Table 2).
Within the observation period, 1.1% (n = 256) of the index population died. The result was adjusted with regard to age and sex to the German general population aged 18 to 65 years (15). With 961/100 000 population, the one-year mortality was 3.4-times higher compared to the age- and sex-matched general population (282/100 00). The cause for mortality is not recorded in the available data. In the random intercept null model, “hospital“, but not “region”, explained variation in mortality. In the 3-level regression model, with regard to fixed effects, age and male sex as sociodemographic risk factors, a primary diagnosis of severe depression as well as psychiatric secondary diagnoses and severe somatic comorbidities (represented by the Charlson index) as illness-related factors, and treatment in a hospital/department of psychiatry and psychotherapy as treatment-related factors were associated with an increased likelihood of mortality. By contrast, prolonged length of inpatient stay and (at least minimal) antidepressant and psychotherapeutic follow-up treatment decreased the likelihood of mortality. McFadden’s Pseudo R2 was 0.16; the predictors thus explained a significant proportion of the variation beyond the hospital-related and regional variation (14) (Table 3 a, b).
To obtain evidence of preventative effects of guideline-adherent treatment, we initially planned to repeat the regression analysis using the more extensive indicators “guideline-adherent medication“ and “guideline-adherent psychotherapy“ for the deaths that occurred during the second half of the year after discharge; however, none of the patients who died during the second half of the year received guideline-adherent treatment during the first half of the year.
The routine data of BARMER show that in Germany inpatient treatment of depression was provided by hospitals/departments of psychiatry and psychotherapy in three of four patients. In 2015, the number of beds was 50 972 in psychiatry (without addiction) to 10 439 in psychosomatic medicine (16). The hospitals/departments of psychiatry and psychotherapy primarily treated patients with severe and psychotic depression, while the hospitals/departments of psychosomatic medicine primarily treated patients with moderate depression. However, treatment density was considerably lower in hospitals/departments of psychiatry and psychotherapy compared to hospitals/departments of psychosomatic medicine. This is due to the requirements of the approximately 30-year-old German Psychiatry Personnel Regulation Act (PsychPV, Psychiatrie-Personalverordnung) which limits the possibilities to provide intensive and guideline-adherent psychotherapy (17, 18). Since staffing in hospitals/departments of psychosomatic medicine is usually not regulated by the PsychPV, in this setting one full-time physician/psychologist is only responsible for the treatment of half as many patients compared to hospitals/departments of psychiatry (19, 20). With 42 days, the length of stay was overall shorter compared to, for example, the situation 15 years ago (21). In the light of the goal to promote the integration of patients into their living environment and the comparable low costs of this care strategy, it is surprising that treatment in day clinics, especially in hospitals/departments of psychosomatic medicine, is the exception, not the rule.
Follow-up outpatient treatment
After discharge, only 8% of patients with severe depression and 50% of patients with moderate depression received guideline-adherent follow-up treatment. In the group of patients with severe depression, only 12% received the follow-up treatment with psychotherapy recommended in the guidelines. The study data did not allow to determine the exact reasons behind this finding. The important role of structural deficits in the German healthcare system, causing this long interval of 16.7 weeks until the start of treatment, is highlighted by the information of the Federal Chamber of Psychotherapists (BPtK, Bundespsychotherapeutenkammer) that nationwide the mean waiting time for a space in psychotherapy is 19.9 weeks, with a high patient preference for this treatment modality (22). These long intervals are of concern because data from the British healthcare system show that with waiting times of more than four weeks the chance of a positive effect of outpatient psychotherapy decreases considerably (23). Structural support could be provided by improved coordination between hospitals, specialists in psychiatry and psychotherapy/general practitioners and guideline psychotherapists (24, 25, 26). Furthermore, although group therapy could expand the psychotherapy offering to compensate for the lack of resources, this rarely happens in Germany, according to chambers of psychotherapists because of bureaucratic hurdles (27).
With regard to follow-up treatment with medication, again significant deficits were identified. Only 57% of patients with severe or psychotic illness received medication for an adequate period of time and in adequate doses—and the indicator chosen for this study represents a very conservative estimate. The available data did not allow conclusions about to what extent this was due to patient concerns about long-term medication use or physicians not adhering to the guideline recommendations.
The association of comorbidities and advanced age with less favorable courses is consistent with the findings reported in the literature (28). The finding that patients treated in a hospital/department of psychiatry and psychotherapy are at a higher risk of readmission can be explained by differences in the patient mix and the more acute treatment setting. The association between inpatient treatment intensity and readmission rates identified in the regression model raises the question of the adequacy of staffing in hospitals/departments of psychiatry and psychotherapy. After discharge, patients receiving follow-up treatment with psychotherapy have a lower risk of readmission in the model, indicating the importance of implementing this guideline recommendation. The finding that guideline-adherent follow-up treatment with medication is associated with an increased likelihood of readmission in the model seems counterintuitive, but may be explained by the fact that the indication for consistent treatment with medication is stricter in patients with more severe illness who consequently are at a greater risk of relapse and recurrence. Alternatively, the finding could be explained by the rebound phenomenon which is triggered by improper discontinuation of antidepressant treatment and has only recently been reported in the literature (29).
Deaths are a key outcome measure of high clinical relevance which is available in the routine data. This study found a mortality rate which was higher than expected. In the year following discharge from hospital after inpatient treatment of depression, the mortality rate was 3.4 times higher compared to the general population. Instead of the expected 65 deaths among 22 893 persons in the general population, 151 more persons died in the (adjusted) index sample of this study. It can be assumed that mortality was reliably recorded in the available dataset. While factors such older age, male sex, severity of depression, combined addictions, the Charlson index, and treatment in a hospital/department of psychiatry and psychotherapy can be used to identify high-risk populations, treatment-related factors highlight the risk of increased mortality associated with a lack of follow-up treatment with psychotherapy and medication as well as shorter inpatient stays. Of particular concern was the finding that none of the patients who died in the second half of the year after discharge had received guideline-adherent treatment in the first six months.
By analyzing administrative health insurance data, large populations and the reality of treatment can be explored over time outside of studies. A disadvantage of routine data is the limited validity of the diagnoses, especially of the severity grading used in this study. Since this study focused on patients who were treated in a specialist hospital or department, a higher validity at least of mental health diagnoses can be assumed; on the other hand, this focus also allowed to capture the reality of outpatient treatment of some of the most severely affected patients. By combining inpatient stays, this study provides a more realistic view on readmissions and the length of hospital stays than previous studies. Since health insurance providers are not allowed to have access to further clinical variables, indicators have to be used to make these accessible. Thus, treatment reality may differ in individual cases. Furthermore, analyzes of routine data can only describe the existing care situation. The regressions performed on the administrative data can only indicate plausible relationships, but do not allow for causal interpretations. In addition, the relationships identified in the regression models are only valid, even on the basis of correlative interpretation, if no unconsidered confounders with substantial effects on the studied outcomes are present. Due to the relatively low number of events compared to the complexity of the statistical models, some results may show bias. Furthermore, it should be taken into account that “guideline adherence” could only be operationalized very broadly in this study, because guidelines, although making general recommendations, explicitly allow to deviate from these recommendations and to take into account factors when making individualized decisions that extend beyond illness severity.
Despite its methodological limitations, which need to be considered, our study reveals potential shortcomings in the care of patients undergoing inpatient treatment. Inpatient treatment in specialist hospitals and departments of psychiatry and psychotherapy was characterized by lower treatment intensity compared to specialist hospitals and departments of psychosomatic medicine and psychotherapy, despite the higher proportion of patients with severe depression and the fact that in the model, intensification of inpatient treatment could counteract readmissions. In addition, longer inpatient stays were associated with reduced mortality risk in the model. Furthermore, our study shows deficits of the follow-up treatment with medication and psychotherapy. Only in a minority of patients, the current guideline recommendations were implemented, despite the fact that in regression models the recommended follow-up treatment could reduce the likelihood of readmissions and death. These results underscore the high relevance of current efforts in research, professional and health policy to improve healthcare structures in a way that enables guideline-adherent treatment in an inpatient care setting independent of the type of hospital/department and in outpatient care within the currently existing sectored structures.
Conflict of interest statement
Mr. Wiegand received co-authorship fees from Springer Medizin Verlag.
The remaining authors declare no conflict of interest.
Manuscript received on 19 September 2019, revised version accepted on 26 March 2020
Translated from the original German by Ralf Thoene, MD.
Hauke Felix Wiegand, MD/PhD
Klinik für Psychiatrie und Psychotherapie, Universitätsmedizin Mainz
Untere Zahlbacher Str. 8
55131 Mainz, Germany
Cite this as:
Wiegand HF, Saam J, Marschall U, Chmitorz A, Kriston L, Berger M, Lieb K, Hölzel LP: Challenges in the transition from in-patient to out-patient treatment in depression—an analysis of administrative health care data from a large German health insurer. Dtsch Arztebl Int 2020; 117: 472–9. DOI: 10.3238/arztebl.2020.0472
(last accessed on 2 January 2020).
(last accessed on 16 April 2020)
Department of Medicine and Health Services Research, BARMER Statutory Health Insurance Fund, Wuppertal, Germany: Joachim Saam, Dr. med. Ursula Marschall
Faculty of Social Work, Health and Nursing Sciences, Esslingen University of Applied Sciences, Esslingen, Germany: Prof. Dr. rer. biol. hum. Andrea Chmitorz
Department of Medical Psychology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany: PD Dr. phil. Levente Kriston
Department of Psychiatry and Psychotherapy, University Hospital Freiburg, Freiburg, Germany: Prof. Dr. med. Mathias Berger
Oberberg Parkklinik Wiesbaden Schlangenbad, Wiesbaden, Germany: Dr. phil. Lars P. Hölzel
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