The size of the patient collective as well as the number of patients in the individual sub-groups increased steadily over time (Fig. 1, data in S table 3). The group ‘KBV record’ comprises all patients who had received at least one outpatient psychotherapeutic service in the year referred to (this corresponds to the line ‘KBV data set’ in S table 2, for example, 2,732,004 in 2019).
In the KBV record, the number of data entries rose from 2,006,249 in 2015 to 2,732,004 in 2019 (change 36.2%), the number of included patients increased from 1,714,777 in 2015 to 2,278,829 in 2019 (change: 32.9%). The total number of mentally ill patients added up to 1,614,458 in 2015 and to 2,110,205 in 2019 (change: 30.7%). For 2019, out of the group of mentally ill patients we could assign 594,870 patients to the group of patients with cMPs (change compared to 2015: 37.4%), 113,626 to the group of intermediate patients (change compared to 2015: 43.7%) and 1,401,709 to the group of patients with MnoP (change compared to 2015: 27.2%).
From 2015 to 2019, the number of patients with cMPs showed a larger increase (37.4%) than the number of patients with MnoP (27.2%). The number of patients who could not be clearly assigned to a sub-group increased the most (43.7%); however, as described above, the absolute frequency of these patients was very low. The largest increases took place from 2016 to 2017 (percentage changes: cMPs 14.1%; MnoP 11.8%; intermediate 14.7%) and then from 2017 to 2018 (percentage changes: cMPs 9.0%; MnoP 7.2%; intermediate 9.3%). For details, see also Fig. 2 and S table 3.
In 2015, 26.8% of the mentally ill patients who got treatment met the criteria of patients with cMPs and 68.3% the criteria of patients with MnoP. The percentages of these two diagnosis groups remained relatively stable but were constantly and slightly shifting in favor of the cMPs group over time. The percentage of patients with cMPs increased from 26.8% to 28.2% (+1.4%) between 2015 and 2019, the percentage of patients with MnoP decreased from 68.3% to 66.4% (-1.9%) between 2015 and 2019. The increases and decreases occurred evenly over the observation period. Only about 5% of the mentally ill could not be clearly assigned either to cMPs or MnoP (intermediate group). This proportion hardly changed over the study period. For details, see Fig. 3 and S table 4.
The results at the level of the billed psychotherapy services essentially reflected the previously reported results of the patient collective. The number of outpatient psychotherapeutic services increased significantly for patients in both cMPs and MnoP groups from 2015 to 2019 (see Fig. 4 and S table 5). The largest increases took place from 2016 to 2017 and from 2017 to 2018.
The number of services billed for patients with cMPs increased slightly more (43.4%) than the number of services billed for patients with MnoP (35.1%) (see Fig. 5 and S table 5).
Within the group of mentally ill patients, around 25% of the services were provided for patients with cMPs and around 70% for patients with MnoP. Only a small proportion of 5% of the services were billed for intermediate patients with mental diseases. Over time, the proportion of services billed for cMPs increased slightly by about 1% and the proportion of services billed for MnoP decreased by about 1.5%. These minimal shifts in percentages occurred evenly over time. For details see Fig. 6 and S table 6).
Fig. 7 and S table 7 show the percentage of patients in each diagnosis group in relation to all treated patients who had received at least one psychotherapeutic service. The figure sums up the individual age cohorts into two groups of 18-49 years and 50-79 years. The absolute frequencies of the included patients as well as the percentage change in each year relative to the previous year and percentage change in 2019 relative to 2015 – differentiated by age in 10-year cohorts, sex, and diagnosis group – can be found in S table 8.
Fig. 7 shows that the percentages of patients with cMPs and MnoP vary considerably with age. Among the 18-49-year-old patients, the percentage of people with cMPs remained relatively constant at just under 19% over the years of the observation period. The percentage was slightly higher for men than for women in 2015 (19.3% versus 18.6%). The percentage of patients with MnoP showed a similar trend. For women under the age of 49, it remained almost unchanged from 2015 to 2019 at around 77.7%. For men under the age of 49, it was 77.9% in 2015 and 2016 and rose minimally to 78.6% in 2018 and 78.7% in 2019.
Among the patients over 50 years of age, the differences in the percentages between men and women as well as the change of the percentages over time were bigger: the percentage of men with cMPs among all men with mental disorders increased continuously from 42.2% in 2015 to 44.5% in 2019 whereas the percentage of men with MnoP fell continuously from 50.8% in 2015 to 47.9% in 2019. The percentage of women with a cMPs increased continuously from 39.1% in 2015 to 41.1% in 2019 while the percentage of women with MnoP dropped continuously from 53.4% in 2015 to 50.9% in 2019. In summary, for people over the age of 50 with mental disorders, the percentage of patients with cMPs was at least three percent higher in men than in women in each calendar year between 2015 and 2019. The percentage of patients with cMPs increased by around 2% between 2015 and 2019 in both men and women (for details S table 8). We also see a particularly high growths in the total number of mentally ill patients in the group of patients aged 50-79 years added up to 572,207 in 2015 and 820,907 in 2019 (change: +43,5%) in comparison to the group of patients aged 18-49 years added up to 1,003,134 in 2015 and 1,232,036 in 2019 (change: + 22,8%) (for details S table 8).
Fig. 8 and S table 9 summarize the percentages of services that are attributable to the respective diagnosis groups, summed up into two age groups of 18-49 years and 50-79 years. All differences in the diagnostic groups differentiated by age and sex and all changes between 2015 and 2019 were identical to those at the level of the patients. However, the percentage of services for patients with cMPs was almost 1% lower than the percentages of the corresponding patient groups among the under 49-year-old people and around 2% lower than the percentages of the corresponding patient groups among the >50-year-old patients.
The findings on the group of >79-year-old patients were the most surprising of all: while 52,023 people >79 years of age received at least one outpatient psychotherapeutic service in Germany in 2015, it was 134,455 in 2019 (S table 10). This represents an increase of 158.4%, far exceeding the absolute increases in all age groups.