There was a total of 73,116 ED visits to the target hospital in 2015, 40,055 of which were for patients between the ages of 18 and 59. Of this latter group, 2,879 presented with mental health issues. In particular, 220 ED visits were related to BPD or self -harming behaviour.
The remaining highest mental health presentations to the ED include:
932 - Mental and behavioural disorders due to psychoactive substance use
452 - Depressive episode, unspecified
403 - Anxiety disorder, unspecified
304 - Acute stress reaction
123 - Unspecified nonorganic psychosis
97 - Schizophrenia, unspecified
Of the 220 BPD and self-harm presentations, there were 192 unique patients. Of these, 129 patients presented once to ED and did not have a follow up ED or crisis presentation. Sixty-three of the 192 unique patients (32.8%) accounted for an additional 66 ED visits within one year from their index visit and 157 visits to crisis. These 63 patients accounted for 286 total visits (including index) to ED/crisis within a one-year time frame. This clearly suggests that there were differences in the level of acuity of this group of patients with BPD.
Many patients had evidence of a POC, a completed CDS, or RAI, either individually or in combination with one or both of the other options (see Table 1). Analysis of variance showed that the differences in ED+CRI counts for these groups is significantly different (p = 0.01). To determine which groups were significantly different from each other a Tukey Multiple Pairwise Comparison test found that subjects receiving all care, POC+CDS+RAI 83/192 (43%), have a significantly higher count of ED+CRI than subjects using none (p = 0.03). These subjects also have the highest use of ED+CRI. Not surprisingly, these findings suggest that the clients who utilize all services more often are the same patients who also utilized the ED and CRI most often.
Table 1. Frequency of POC visits and Completion of CDS or RAI
Group
|
N
|
Mean # ED+CRI
|
SD
|
POC only
|
10
|
0.10
|
0.32
|
CDS only
|
12
|
0.58
|
1.00
|
RAI only
|
13
|
0.15
|
0.38
|
CDS + POC
|
13
|
2.23
|
2.28
|
RAI + POC
|
17
|
0.24
|
0.44
|
CDS + RAI
|
13
|
0.92
|
1.04
|
CDS + RAI + POC
|
83
|
4.66
|
10.00
|
NONE
|
31
|
0.03
|
0.18
|
Overall, the mean number of ED+CRI visits for all subjects in the study period (not including the index visit) was 2.3. The minimum was 0 and the maximum 70.
There were a large number of subjects with no visits to either ED or CRI aside from the index visit. Fifty-four percent (104/192) of subjects had only one visit to ED or CRI in the study period before or after the index visit. Considering ED and CRI separately, 80% of patients do not have additional ED visits in the year before or the year after the index visit and 59% of subjects do not visit Crisis Services in the years before or after the index visit. Considering only the subjects who had at least one additional visit to ED or CRI, the mean number of visits in the study period was 5.0. Figure 1 shows the number of ED+CRI visits grouped by whether the subject had a CDS, a RAI or was seen in POC.
Figure 1: Number of ED+CRI visits grouped by whether the subject had a CDS, a RAI and was seen in POC.
A generalized linear model with a negative binomial distribution was found to be the most appropriate for analyzing factors affecting the number of ED + CRI visits. The response variable, the total number of ED+CRI visits per patient in the year before and after the index visit, is represented by a count of the number of visits for each study subject. Other variables in the model were as follows: The number of POC visits, indicating the number of times the subject was seen by a psychiatrist during the study period. CDS and RAI are indicators of whether a CDS or RAI assessment was done during the study period. For those 121 subjects who had a CDS assessment, 15 of them were done on the same day as the index visit, 72 were done after the visit date and 34 were before after the visit date. A total of 126 subjects had an RAI assessment done, 3 of which were done on the same day as the visit date, 15 were done before the visit data and 108 were done afterwards. Also included in the model were subject age and sex, and whether the index visit indicated self -harm or BPD.
The model was selected based on a stepwise method using the Akaike Information Criterion which is used to determine the best model fit. The best fitting model found that the following variables were significant at p < 0.05: the number of POC visits, whether a CDS assessment was done, and whether an RAI assessment was done. Sex was trending toward significance and it helped improve model fit therefore it was kept in the model.
Table 2. Final Model Output
Coefficients
|
Estimate
|
Std. Error
|
Pr(>lzl)
|
Intercept
|
-2.88891
|
0.44977
|
1.34e-10
|
Total POC
|
0.03960
|
0.01144
|
0.00054
|
CDS any
|
2.85205
|
0.42236
|
1.45e-11
|
RAI any
|
0.78554
|
0.32879
|
0.01688
|
sex: Male
|
0.47763
|
A 0.26066
|
0.06690
|
All variables in the model except for sex are significant at a p value < 0.02. However, sex has a p value of approximately 0.07 and is trending toward significance. In addition, male subjects have a higher expected count of ED+CRI visits (p= 0.07).
Below we present a table showing the expected counts of ED+CRI. We stop at 20 POC visits since there were only 6 subjects with greater than 20 visits (2 male, 4 female).
Table 3. Expected Counts of ED + CRI Visits
# POC visits
|
CDS completed
|
RAI completed
|
Sex
|
Expected # of visits
|
None
|
No
|
No
|
Female
|
0.056
|
None
|
Yes
|
No
|
Female
|
0.964
|
None
|
No
|
Yes
|
Female
|
0.122
|
None
|
No
|
No
|
Male
|
0.090
|
1
|
No
|
No
|
Female
|
0.058
|
10
|
No
|
No
|
Female
|
0.083
|
20
|
No
|
No
|
Female
|
0.183
|
These results indicate that the subjects who do not require a POC, RAI and CDS present the least often to ED+CRI. Subjects requiring ‘POC only’ with less than 20 POC visits in the study period present to ED and CRI less often than the subjects who also have a CDS or RAI assessment. Having a CDS, or an RAI, or being male increases the expected count of ED + CRI visits. As the number of POC visits increases, so does the expected count of ED + CRI visits. Analysis shows that as total POC visits increase, so do predicted ED+CRI visits. Self -harm and BPD at index visit were not found to be significant predictors of the number of ED+CRI visits during the study period.
Subgroup analysis: Subset of those with any ED+CRI visits
A logistic regression on factors affecting a decrease in ED+CRI visits year over year was run. Although a large portion of the subjects had no ED or CRI visits before or after the index visit, it is of clinical interest to examine characteristics of those subjects with a positive count in ED+CRI, specifically whether the number of visits increased or decreased from year 1 to year 2 in the study period.
A total of 34/88 subjects (38.6%) of these subjects had a year over year decrease in the number of ED+CRI visits, 11/88 (12.5%) experienced the same number of visits, and 43/88 (48.9%) experienced an increase in the number of visits from year 1 to year 2. The only significant variable found to contribute to a decrease in the number of ED+CRI visits was whether a CDS assessment was done in the first year of the study (i.e., prior to the index visit). The log odds of having a decrease in visits in year 2 if a CDS assessment is done before the index visit is 1.48 with a 95% confidence interval (0.54, 2.47). This means that a CDS assessment before the index visit significantly increased the odds of having a decrease in the total number of ED+CRI visits in the second year of the study (p=0.0025).
Psychiatric Outpatient Clinic: Standard vs Unique Model of Care
We conducted several analyses to determine if there were differences between the ED and CRI visits of patients receiving traditional care or care in the unique model. There were 123 subjects (64.1%) seen in POC either before or after the index visit. Of these, 70 subjects had a POC visit prior to the index visit, 117 had a POC visit after the index visit and 64 subjects had a POC visit both before and after the index visit. For this group of 64 subjects, we calculated the overall mean time between the last POC visit before the index and the next POC visit after the index visit as 104 days.
For the first model of care, for everyone with a POC visit prior to the index (70 subjects), the mean time between the POC visit prior to the index visit and the date of the index visit itself was 76 days. For everyone with a POC visit following the index (117 subjects), the mean time between the POC visit after the index visit and the date of the next POC visit was 77 days.
Six subjects were seen in the unique practice model, with a setup meant to allow more accessibility. Of these six subjects, five were seen in POC both before and after the index visit. The mean time between the last POC visit before the index visit and the next POC visit after the index visit for these five subjects was 44 days, compared to the much larger mean for the other 59 subjects in the traditional practice model at 109 days. With the caveat that the sample size for the accessible practice model is small (n= 5 vs n = 59), we carried out Welch’s two sample t test for comparing means with unequal variances and found that the accessible practice model subjects have a significantly shorter time between POC visits (p=0.0001).
We used Fisher’s Exact Test for Count Data to analyse differences in the number of ED+CRI visits, by practice model. While not reaching statistical significance (p>0.05) the findings are still clinically relevant. Again, with our small sample size, this result should be interpreted with caution, however, clinically, in this POC subset, 4/6 (66.7%) of subjects in the accessible practice model had 0 ED+CRI visits while in the traditional practice model, 45/117 (38.5%) of subjects had 0 ED+CRI visits.
For the unique practice model, the mean time between the POC visit prior to the index visit and the date of the index visit itself was 21 days (5 subjects). For everyone with a POC visit following the index (6 subjects), the mean time between the POC visit after the index visit and the date of the next POC visit was 24 days. For the traditional practice model, the mean time between the POC visit prior to the index visit and the date of the index visit itself was 80 days (65 subjects). For everyone with a POC visit following the index (111 subjects), the mean time between the POC visit after the index visit and the date of the next POC visit was also 80 days.