Abstract
Introduction
Intensive outpatient programs (IOPs) have been shown to reduce posttraumatic stress disorder (PTSD) symptoms in veteran populations. The aim of this study was to examine the association between IOP participation and inpatient psychiatric and mental health–related emergency department (ED) encounters among patients with PTSD.
Methods
This is a retrospective cohort study among 258 adults with PTSD who participated in the IOP at Kaiser Permanente Oakland Medical Center between January 1, 2017, and December 31, 2018. The authors compared changes in inpatient psychiatric hospitalizations and mental health–related ED encounters from the year before vs after the first IOP engagement. Bivariate analyses comparing ED and inpatient utilization pre- and post-IOP engagement, stratified by sociodemographic variables were conducted using paired t-tests and McNemar’s test. Conditional multivariable logistic regression was performed to assess the odds of psychiatric utilization.
Results
Participants were more likely to have ≥ 1 inpatient psychiatric encounter (28.7% vs 15.9%; p < 0.01) and ≥ 1 mental health–related ED encounter (24.8% vs 18.2%; p = 0.04) pre-IOP vs post-IOP. The authors’ multivariable analysis demonstrated that patients experienced a 56% reduction in the odds of inpatient psychiatric encounters (adjusted odds ratio = 0.42, 95% confidence interval: 0.26–0.68, p < 0.01) and a 35% reduction in mental health–related ED encounters (adjusted odds ratio = 0.63, 95% confidence interval: 0.40–1.00, p = 0.05) post-IOP vs pre-IOP.
Discussion
This study demonstrated a significant reduction in inpatient psychiatric hospitalizations and mental health–related ED visits among patients with PTSD in the year following participation in an IOP.
Conclusion
These findings support the use of IOPs for patients with PTSD to reduce the likelihood of intensive service use.
Keywords: Intensive outpatient program, Post-traumatic stress disorder, inpatient psychiatric encounters, mental health-related emergency department encounters
Posttraumatic stress disorder (PTSD) is a psychiatric condition characterized by a range of anxiety-based symptoms that persist ≥ 1 month following exposure to trauma.1 PTSD is one of the most common psychiatric disorders in the United States, with a lifetime prevalence estimated at 6.1%, affecting > 14 million adults.2
The cost of PTSD in the United States is substantial. Among all US civilians, active-duty military personnel, and veterans, the estimated annual cost of PTSD in the United States is $232.2 billion, $19,630 per individual with PTSD.3 Of this cost, 81.6% is from the civilian population, and 18.4% from the military population.3 The main drivers of total PTSD-related costs across both populations are direct health care delivery expenses, followed by unemployment and disability benefit distributions.3
The cost of direct health care services among the 2 populations is substantial, totaling $71.1 billion.3 Several studies analyzing health care utilization across various patient populations have demonstrated significantly higher utilization rates among patients with PTSD compared to those among patients without mental health disorders or among patients with psychiatric disorders other than PTSD.4–6 One such study that compared patients with PTSD to matched control participants with major depressive disorder found that total annual health care cost differences were significantly higher for the PTSD cohort (4.2% and 9.3%, for Medicaid vs private insurance, respectively, p < 0.05). Drivers of the cost differences included higher all-cause emergency department (ED) and outpatient resources, as well as more calendar days with mental health–related hospitalization among patients with PTSD.4
One model for delivering trauma-based psychotherapy and medication management with known efficacy for PTSD is to enroll patients in an intensive outpatient program (IOP). These programs generally consist of consolidated weekly treatment. This is often structured as half-days, attended for 2–4 weeks, where various focused therapeutic interventions are delivered by a multidisciplinary approach involving psychologists, psychiatrists, and other mental health professionals.7,8
Most of the research on the efficacy of IOP in reducing PTSD symptoms has been conducted in veteran populations.7–9 Evidence from these studies suggests IOP can be helpful in reducing symptom severity and producing clinically meaningful responses while increasing treatment retention and extending the durability of treatment gains beyond the completion of the IOP.10 Less is known about the impact of IOP participation on future intensive health care use patterns by IOP graduates.
This study aims to examine changes in health care service use before and after IOP engagement among a diverse, civilian adult population with PTSD with a focus on intensive services, specifically admissions to inpatient psychiatry units and visits to the ED.
Methods
The authors performed a retrospective cohort study of patients ≥ 18 years old with PTSD based on International Classification of Diseases, 10th Revision codes (F43.1, F43.10, F43.11, F43.12) who participated in the Kaiser Permanente Oakland Medical Center (Kaiser Permanente Oakland) IOP between January 1, 2017, and December 31, 2018, and had continuous Kaiser Permanente Northern California coverage 1 year prior to the index date (date of patient’s first IOP enrollment) to 1 year after the index date.
Kaiser Permanente Northern California is an integrated health system that insures more than one-third of Northern California’s population.11 The Kaiser Permanente Oakland IOP serves Kaiser Permanente patients (“members”) in the East Bay region who are experiencing acute psychiatric distress and need a higher level of care than provided in the traditional outpatient setting. Many of the patients are referred to IOP after discharge from hospitals, crisis residential settings, or partial hospital programs (considered a step down from higher levels of care). Alternatively, patients may be referred directly by their treating therapist or psychiatrist in the outpatient setting if they are experiencing acute psychiatric distress but whose symptoms but do not meet criteria for residential or inpatient psychiatric treatment (considered a hospitalization diversion; Figure).
Figure:
Kaiser Permanente Oakland Medical Center IOP flowchart. IOP = intensive outpatient program.
The program consists of 3 days per week of half-day programming in which patients are engaged in group therapies—with modalities ranging from mindfulness-based to trauma-informed to cognitive behavioral and dialectical behavioral—as well as individual therapy, and psychiatric medication management. Interventions that occur in IOP are crisis stabilization and early treatment. Patients are assigned a designated case manager throughout their enrollment who helps ensure care collaboration among the patient’s multidisciplinary practitioners and assists with transitions in care after IOP completion. IOP is designed to treat patients “in crisis,” so case managers are primarily focused on identifying safety and self-care concerns first, then moving quickly into skills and insight building to increase safety and improve self-care. This is done through teaching skills such as “trauma grounding” and the ability to identify what is and what is not safe. The role of IOP is eventually connecting patients to the treatment indicated by diagnosis, for example, identifying when an intervention, such as eye movement desensitization and reprocessing is appropriate. IOP is a resource to help patients stabilize to a position in which they can engage and gain maximum benefit when transitioned to the indicated care (Figure).
The length of time spent in the program is individualized, but on average patients are enrolled for 4–6 weeks. The first week focuses on “basics,” such as case managers helping the patient identify what they are doing well and what needs improvement in terms of sleep, nutrition, movement, medicine, and other factors. They also focus on identifying the patients’ current stressors that are contributing to crisis and encourage a break from those stressors (eg, time off work or pausing relationship decisions). The second through fourth weeks in IOP, therapy focuses on building up what the patient is going to do differently moving forward. This can include psychotherapy skills, such as mindfulness, thought challenging, grounding, emotion regulation, among others. The interventions used vary based on each patients’ individual needs.
All sociodemographic, psychiatric diagnostic, and clinical utilization data were extracted from Kaiser Permanente Northern California’s electronic health record system. The authors compared changes in psychiatric utilization, namely inpatient psychiatric hospitalizations, and ED encounters with any mental health–related encounter diagnosis, from the year prior to the index date to the year following the index date, with each patient acting as their own control.
Analyses reflecting changes in mental health–related and psychiatric ED and inpatient utilization were conducted, comparing the 12 months prior to and the 12 months after the index date. Bivariate analyses comparing ED and inpatient utilization pre- and post-IOP engagement, stratified by sociodemographic variables were conducted using paired t-tests for continuous variables and McNemar’s tests for categorical variables.
Conditional multivariable logistic regression was performed to assess the odds of psychiatric utilization, with time period (post-IOP vs pre-IOP) as the primary predictor, adjusting for age, sex, race/ethnicity, Medi-Cal/Medicare enrollment status, neighborhood median household income, anxiety disorder, depressive disorder, bipolar disorder, substance use disorder (which includes alcohol, marijuana, opiate, and other drug disorders), and other psychiatric disorders (which includes personality, psychotic, feeding and eating, somatic, and obsessive-compulsive disorders).
All data management and analyses were performed using SAS (version 9.4; SAS Institute Inc.). The study was approved by the Kaiser Permanente Northern California Institutional Review Board.
Results
The authors identified 258 patients with PTSD at Kaiser Permanente Oakland who had participated in IOP during the observation period. The median duration of IOP engagement was 28 days [interquartile range (IQR): 11–78 days]. A large proportion of this cohort (83%) was female. The mean age in years was 39.3 ± 14.0 and the majority of the population was non-White; however, non-Hispanic White patients made up the largest ethnicity category (44%). Psychiatric comorbidity was high, with depressive disorders (85%) followed by anxiety disorders (64%; Table 1).
Table 1:
Patient demographics and clinical characteristics (N = 258)
| Patient characteristic | |
|---|---|
| Sex, n (%) | |
| Female | 213 (82.6) |
| Male | 45 (17.4) |
| Age at index, y, mean (SD) | 39.3 (14.0) |
| Age at index, y, n (%) | |
| 18–24 | 52 (20.2) |
| 25–29 | 25 (9.7) |
| 30–34 | 28 (10.9) |
| 35–39 | 30 (11.6) |
| ≥ 40 | 123 (47.7) |
| Neighborhood median household income, median (IQR) | $75,565 ($58,493–$100,494) |
| Race/ethnicity, n (%) | |
| Non-Hispanic White | 114 (44.2) |
| Black | 70 (27.1) |
| Asian | 18 (7.0) |
| Hispanic | 36 (14.0) |
| Other | 20 (7.8) |
| Medi-Cal/Medicare enrollment status, n (%) | 40 (15.5) |
| Comorbid psychiatric diagnosis, n (%) | |
| Depressive disorder | 220 (85.3) |
| Anxiety disorder | 166 (64.3) |
| Psychotic disorder | 33 (12.8) |
| Personality disorder | 25 (9.7) |
| Bipolar disorder | 60 (23.3) |
| Feeding and eating disorder | 17 (6.6) |
| Obsessive-compulsive disorder | 17 (6.6) |
| Somatic disorder | 7 (2.7) |
| Alcohol-related disorder | 42 (16.3) |
| Cannabis-related disorder | 39 (15.1) |
| Tobacco-related disorder | 43 (16.7) |
| Opioid-related disorder | 6 (2.3) |
| Other drug disorder | 36 (14.0) |
IQR, interquartile range; SD, standard deviation.
The authors’ primary analysis demonstrated that in the 12 months before IOP, participants were more likely to have ≥ 1 inpatient psychiatric encounter, compared to in the 12 months following IOP (28.7% vs 15.9%; p < 0.01;). Similarly, in the 12 months before IOP, participants were more likely to have ≥ 1 mental health–related ED encounter, compared to in the 12 months following IOP (24.8% vs 18.2%; p = 0.04). The mean (SD) number of inpatient psychiatric encounters (0.3 ± 0.5 vs 0.2 ± 0.5; p ≤ 0.01) and mental health–related ED encounters (0.5 ± 1.3 vs 0.3 ± 1.0; p = 0.03) was also lower in the 12 months following IOP compared with the 12 months prior to IOP engagement (Table 2).
Table 2:
Psychiatric utilization 12 months prior to and following intensive outpatient program engagement (N = 258)
| Psychiatric utilization outcome | Before IOP engagement | After IOP engagement |
P value |
|---|---|---|---|
| Number of inpatient psychiatric encounters, mean (SD) a | |||
| Overall | 0.3 (0.5) | 0.2 (0.5) | < 0.01 |
| Sex | |||
| Female | 0.3 (0.5) | 0.2 (0.5) | 0.01 |
| Male | 0.4 (0.6) | 0.2 (0.6) | 0.16 |
| Age at index, y, mean (SD) | |||
| 18–24 | 0.6 (0.6) | 0.3 (0.4) | 0.01 |
| 25–29 | 0.3 (0.5) | 0.2 (0.4) | 0.38 |
| 30–34 | 0.1 (0.3) | 0.1 (0.3) | 1.00 |
| 35–39 | 0.2 (0.4) | 0.1 (0.4) | 0.75 |
| ≥ 40 | 0.3 (0.5) | 0.2 (0.6) | 0.13 |
| Neighborhood median household income, mean (SD) | |||
| Below median | 0.3 (0.5) | 0.1 (0.4) | < 0.01 |
| Above median | 0.3 (0.5) | 0.3 (0.5) | 0.39 |
| Race/ethnicity, mean (SD) | |||
| Asian | 0.4 (0.5) | 0.2 (0.4) | 0.06 |
| Black | 0.3 (0.5) | 0.1 (0.3) | < 0.01 |
| Hispanic | 0.3 (0.5) | 0.2 (0.5) | 0.44 |
| Other | 0.3 (0.6) | 0.1 (0.2) | 0.16 |
| Non-Hispanic White | 0.3 (0.5) | 0.3 (0.6) | 0.9 |
| Medi-Cal/Medicare enrollment status, mean (SD) | |||
| Yes | 0.2 (0.4) | 0.3 (0.8) | 0.67 |
| No | 0.3 (0.5) | 0.2 (0.5) | < 0.01 |
| Had ≥ 1 inpatient psychiatric encounters, n (%)b | |||
| Overall | 74 (28.7) | 41 (15.9) | < 0.01 |
| Sex | |||
| Female | 58 (27.2) | 33 (15.5) | < 0.01 |
| Male | 16 (35.6) | 8 (17.8) | 0.05 |
| Age at index, y, n (%) | |||
| 18–24 | 27 (51.9) | 14 (26.9) | 0.02 |
| 25–29 | 7 (28.0) | 4 (16.0) | 0.37 |
| 30–34 | 3 (10.7) | 3 (10.7) | 1 |
| 35–39 | 5 (16.7) | 3 (10.0) | 0.41 |
| ≥ 40 | 32 (26.0) | 17 (13.8) | 0.01 |
| Neighborhood median household income, n (%) | |||
| Below median | 37 (28.5) | 12 (9.2) | < 0.01 |
| Above median | 37 (28.9) | 29 (22.7) | 0.26 |
| Race/ethnicity, n (%) | |||
| Asian | 8 (44.4) | 3 (16.7) | 0.06 |
| Black | 22 (31.4) | 6 (8.6) | < 0.01 |
| Hispanic | 11 (30.6) | 7 (19.4) | 0.25 |
| Other | 4 (20.0) | 1 (5.0) | 0.18 |
| Non-Hispanic White | 29 (25.4) | 24 (21.1) | 0.41 |
| Medi-Cal/Medicare enrollment status, n (%) | |||
| Yes | 3 (21.4) | 2 (14.3) | 0.32 |
| No | 71 (29.1) | 39 (16.0) | < 0.01 |
| Number of mental health–related ED encounters, mean (SD) a | |||
| Overall | 0.5 (1.3) | 0.3 (1.0) | 0.03 |
| Sex, mean (SD) | |||
| Female | 0.5 (1.4) | 0.3 (1.0) | 0.02 |
| Male | 0.4 (0.9) | 0.4 (0.9) | 0.87 |
| Age at index, y, mean (SD) | |||
| 18–24 | 0.8 (1.5) | 0.5 (1.5) | 0.02 |
| 25–29 | 0.6 (0.8) | 0.2 (0.7) | 0.03 |
| 30–34 | 0.1 (0.3) | 0.0 (0.0) | 0.08 |
| 35–39 | 0.1 (0.3) | 0.2 (0.5) | 0.54 |
| ≥ 40 | 0.4 (1.6) | 0.4 (1.0) | 0.48 |
| Neighborhood median household income, mean (SD) | |||
| Below median | 0.5 (1.7) | 0.3 (1.2) | 0.02 |
| Above median | 0.4 (0.8) | 0.3 (0.7) | 0.51 |
| Race/ethnicity, mean (SD) | |||
| Asian | 0.6 (1.2) | 0.4 (1.1) | 0.69 |
| Black | 0.3 (0.8) | 0.1 (0.4) | 0.18 |
| Hispanic | 0.6 (1.5) | 0.5 (1.7) | 0.62 |
| Other | 0.2 (0.4) | 0.1 (0.2) | 0.19 |
| Non-Hispanic White | 0.5 (1.6) | 0.4 (1.0) | 0.13 |
| Medi-Cal/Medicare enrollment status, mean (SD) | |||
| Yes | 0.3 (0.7) | 0.1 (0.3) | 0.19 |
| No | 0.5 (1.4) | 0.3 (1.0) | 0.04 |
| Had ≥ 1 mental health–related ED encounters, n (%) b | |||
| Overall | 64 (24.8) | 47 (18.2) | 0.04 |
| Sex | |||
| Female | 52 (24.4) | 36 (16.9) | 0.04 |
| Male | 12 (26.7) | 11 (24.4) | 0.78 |
| Age at index, y, n (%) | |||
| 18–24 | 22 (42.3) | 12 (23.1) | 0.03 |
| 25–29 | 11 (44.0) | 4 (16) | 0.02 |
| 30–34 | 3 (10.7) | 0 (0.0) | < 0.01 |
| 35–39 | 4 (13.3) | 5 (16.7) | 0.71 |
| ≥ 40 | 24 (19.5) | 26 (21.1) | 0.73 |
| Neighborhood median household income, n (%) | |||
| Below median | 31 (23.9) | 12 (9.2) | 0.02 |
| Above median | 33 (25.8) | 29 (22.7) | 0.54 |
| Race/ethnicity, n (%) | |||
| Asian | 5 (27.8) | 2 (11.1) | 0.18 |
| Black | 12 (17.1) | 9 (12.9) | 0.44 |
| Hispanic | 13 (36.1) | 10 (17.8) | 0.44 |
| Other | 4 (20.0) | 1 (5.0) | 0.18 |
| Non-Hispanic White | 30 (26.3) | 25 (21.9) | 0.38 |
| Medi-Cal/Medicare enrollment status, n (%) | |||
| Yes | 2 (14.3) | 1 (7.1) | 0.32 |
| No | 62 (25.4) | 46 (18.9) | 0.06 |
Bold text indicates p < 0.05.
p value calculated using paired t-test.
p value calculated using McNemar’s test.
ED, emergency department; IOP, intensive outpatient program; SD, standard deviation.
When stratified by sociodemographic variables, the authors found that patients 18–24 years old had a significant reduction in all primary outcomes; namely, mean number of inpatient psychiatric encounters (0.6 ± 0.6 vs 0.3 ± 0.4; p = 0.01), the mean number of mental health–related ED encounters (0.8 ± 1.5 vs 0.5 ± 1.5; p = 0.02), ≥ 1 inpatient psychiatric encounters (51.9% vs 26.9%; p = 0.02), and ≥ 1 mental health–related ED encounters (42.3% vs 23.1%; p = 0.03) in the 12 months post-IOP. Patients who were 25–29 years old had a significant reduction in mean number of mental health–related ED encounters (0.6 ± 0.8 vs 0.2 ± 0.7; p = 0.03) and ≥ 1 mental health–related ED encounters (44% vs 16%; p = 0.02) in the 12 months post-IOP. Patients who were 30–34 years old had a significant reduction only in ≥ 1 mental health–related ED encounters in the 12 months post-IOP (10.7% vs 0%; p < 0.01).
Female patients had significant reduction in all primary outcomes; namely, mean number of inpatient psychiatric encounters (0.3 ± 0.5 vs 0.2 ± 0.5; p = 0.01), ≥ 1 inpatient psychiatric encounters (27.2% vs 15.5%; p < 0.01), and ≥ 1 mental health–related ED encounters (24.4% vs 16.9%; p = 0.04) in the 12 months post-IOP. On the other hand, male patients did not have significant reductions in any of the primary outcomes. Patients with below–median neighborhood household income also had significant reductions in all measures: mean number of inpatient psychiatric encounters (0.3 ± 0.5 vs 0.1 ± 0.4; p < 0.01), ≥ 1 inpatient psychiatric encounters (28.5% vs 9.2%; p < 0.01), and ≥ 1 mental health–related ED encounters (23.9% vs 9.2%; p = 0.02) in the 12 months post-IOP. Patients who identified as Black had a significant reduction in 2 primary outcomes; namely, mean number of inpatient psychiatric encounters (0.3 vs 0.1; p < 0.01) and ≥ 1 inpatient psychiatric encounters (31.4% vs 8.6%; p < 0.01) in the 12 months post-IOP. Patients not enrolled in Medi-Cal/Medicare also had a significant reduction in the same primary outcomes; namely, mean number of inpatient psychiatric encounters (0.3 ± 0.5 vs 0.2 ± 0.3; p < 0.01) and ≥ 1 inpatient psychiatric encounters (29.1% vs 16.0%; p < 0.01) in the 12 months post-IOP (Table 2).
The multivariable analysis, which adjusted for factors including age, sex, race/ethnicity, neighborhood median household income, Medi-Cal/Medicare enrollment status, anxiety disorder, depressive disorder, bipolar disorder, substance use disorder, and other psychiatric disorders, revealed that patients post-IOP, compared to those pre-IOP, experienced a 56% reduction in the adjusted odds ratio (aOR) of inpatient psychiatric encounters [aOR = 0.42, 95% confidence interval (CI): 0.26–0.68, p < 0.01]. Additionally, the odds of mental health–related ED encounters for post-IOP patients were 35% lower (aOR = 0.63, 95% CI: 0.40–1.00, p = 0.05) compared to pre-IOP patients, trending toward significance (Table 3).
Table 3:
Adjusted odds ratios of psychiatric encounters after intensive outpatient program engagement vs before intensive outpatient program engagement (N = 258)
| Outcome | Adjusted odds ratio | 95% CI | P value |
|---|---|---|---|
| Inpatient psychiatric encounter | 0.42 | 0.26–0.68 | < 0.01 |
| Mental health ED encounter | 0.63 | 0.40–1.00 | 0.05 |
Models are adjusted for age, sex, race/ethnicity, neighborhood median household income, depressive disorder, anxiety disorder, bipolar disorder, substance use disorder, and other psychiatric disorders (which includes psychotic disorder, personality disorder, feeding and eating disorder, somatic disorder, and obsessive-compulsive disorder), and Medi-Cal/Medicare enrollment status.
CI, confidence interval; ED, emergency department.
Discussion
To date, there has been a lack of data outlining how service use, rather than symptom severity or remission, might change after patients participate in intensive outpatient clinical services. IOPs are cost intensive to administer, and so it is important to understand how this intervention might impact other patterns of intensive psychiatric care utilization. This study provided an opportunity to evaluate intensive outpatient care outcomes in an integrated system for adult patients with PTSD. This study’s data demonstrated a significant reduction in inpatient psychiatric hospitalizations and a trend toward significance in mental health–related ED visits among patients with PTSD who participated in the Kaiser Permanente Oakland IOP.
A desired outcome of IOP engagement is hospital diversion, which reduces the use of expensive inpatient care. This study suggests that this goal is being achieved and, therefore, has significant potential impact for health care savings. Compared with inpatient care, IOPs also offer several advantages for patients. First, they offer increased treatment duration, which can be tailored to the patient’s individual needs. Second, they provide this treatment from the setting of a patient’s home environment or community, which affords the opportunity to practice newly learned skills immediately in the context of the patient’s individualized life. IOP can be extremely helpful in clarifying for patients in crisis how or when their trauma symptoms manifest, as well as what treatments, skills, and/or techniques will work for them. These patterns of results suggest that trauma-informed IOPs may also be beneficial for patients with PTSD. By integrating core concepts of trauma-informed care (including establishing a safe environment, building trust, integrating peer support, empowering patients, leveraging shared decision making, and addressing stereotypes and biases), IOPs may address the unique needs of patients with PTSD alongside patients with other mental health conditions. IOPs are an important service for inclusion as a covered benefit for patients with PTSD. The authors believe that more health systems should provide ongoing pharmacological and behavioral therapies within a continuing care model that increasingly relies on IOP settings rather than on emergency and inpatient care.
When stratified by sociodemographic variables, patients who were 18–24 years old, who identified as female or as Black, and who had below–median neighborhood household income, had significantly reduced rates of inpatient psychiatric hospitalizations and/or mental health–related ED visits compared with patients with other sociodemographic characteristics. Previous literature often demonstrates higher utilization of emergency medical resources and psychiatric hospitalizations among vulnerable populations (such as those listed above) due to socioeconomic factors such as financial insecurity, care fragmentation, lack of social support, and unsafe living conditions.6,12,13 The findings from the present study provide hope toward greater health equity through the use of IOPs rather than ED visits or hospitalizations. They warrant further investigation in larger samples to determine whether specific sociodemographic groups of adults with PTSD may benefit more than others from IOP.
The present study has several limitations. First, the authors did not observe trends in pharmacotherapy use. IOPs are a complex intervention that includes several different subtreatments, a common one being utilization of psychotropic medications. The authors were not able to control for this variable in the study, nor track trends of psychotropic use. Second, the PTSD diagnoses that were coded in the electronic health record were not confirmed by the PTSD Checklist for Diagnostic and Statistical Manual of Mental Illnesses or another standardized diagnostic or symptom tool. Therefore, the present study’s data relied on the diagnosing clinician’s impression. Third, the data were collected before the COVID-19 pandemic, during which time IOP was conducted in an in-person setting, as opposed to the now hybrid (virtual and in-person) format in which it is being delivered. Although the groups in the present study met during the same time windows and covered the same topics with the same therapists, it is unclear whether the hybrid delivery will have the same efficacy; this would be an excellent consideration for future research. It is also unclear from this study’s data which specific elements within the integrated IOP intervention were most effective in ultimately reducing intensive health care utilization. Conducting a more nuanced investigation of which components of IOP might be influencing these trends would be useful to inform future program directions. Finally, the single-center nature of the study served as a limitation, as the authors could not expand the data collection, given variances of coding practices from facility to facility. Also, the relatively small number of patients in this study’s sample who were insured by Medicaid (Medi-Cal) or Medicare limited the authors’ ability to draw inferences about this population.
Future studies assessing whether this study’s findings are generalizable to other regions and academic centers are needed. Additionally, studies that include a longer-term follow-up as an extension of this project are warranted. PTSD is a notoriously treatment-resistant condition. Understanding these trends beyond the first year of IOP completion would be helpful. Last, as mentioned above, future studies implementing virtual delivery of IOP are also needed.
Conclusions
These findings suggest a meaningful opportunity to engage patients with PTSD in IOPs to prevent future ED visits or hospitalizations. The data do not tell us about associations between IOP and long-term symptom/diagnosis changes, but they do suggest that participation in IOP is helpful in changing future directions of where and how patients seek care when in crisis.
Acknowledgments
The authors express their appreciation to the members of Kaiser Permanente Northern California, whose health is the ultimate goal of this work and who were the source of the data for this study. The authors acknowledge the patients and their data in the electronic health record included in this report. In addition, the authors thank Alexander J Altman, MD (Department of Adult and Family Medicine, Kaiser Permanente Oakland Medical Center, Oakland, CA) and Nathan Lingafelter, MD (North Shore Physicians Group, Salem, MA) for their guidance in the initial conceptualization of this project and Dana Nadel (Kaiser Permanente Northern California Division of Research; Pleasanton, CA) for her assistance with the graphic design of the figure in this manuscript.
Footnotes
Author Contributions: Kathryn H Brown, MD, MBA, participated in data collection, data analysis, and manuscript preparation. Brittany M Abeldt, MD, participated in critical review, drafting, and submission of the final manuscript. Julia Wei, MPH, participated in study design, data collection, data analysis and manuscript review, preparation, and final submission. Nirmala D Ramalingam, MPP, and Matthew E Hirschtritt, MD, MPH, participated in study design, data collection, data analysis, as well as manuscript review, preparation, and final submission.
Conflict of Interest: None declared
Funding: Funding for this study was provided by Kaiser Permanente Northern California Office of Graduate Medical Education.
Data-Sharing Statement: Underlying data are not available.
References
- 1. American Psychiatric Association . Diagnostic and statistical Manual of Mental Disorders. In: Fifth Edition, Text Revision. ; 2013. 10.1176/appi.books.9780890425596 [DOI] [Google Scholar]
- 2. Goldstein RB, Smith SM, Chou SP, et al. The epidemiology of DSM-5 posttraumatic stress disorder in the United States: Results from the National Epidemiologic Survey on Alcohol and Related Conditions-III. Soc Psychiatry Psychiatr Epidemiol. 2016;51(8):1137–1148. 10.1007/s00127-016-1208-5 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3. Davis LL, Schein J, Cloutier M, et al. The economic burden of posttraumatic stress disorder in the United States from a societal perspective. J Clin Psychiatry. 2022;83(3):21m14116. 10.4088/JCP.21m14116 [DOI] [PubMed] [Google Scholar]
- 4. Ivanova JI, Birnbaum HG, Chen L, et al. Cost of post-traumatic stress disorder vs major depressive disorder among patients covered by Medicaid or private insurance. Am J Manag Care. 2011;17(8):e314–e323. Accessed 11 April 2024. https://www.ajmc.com/view/ajmc_11julaug_ivanova_e314to23 [PubMed] [Google Scholar]
- 5. Kartha A, Brower V, Saitz R, Samet JH, Keane TM, Liebschutz J. The impact of trauma exposure and post-traumatic stress disorder on healthcare utilization among primary care patients. Med Care. 2008;46(4):388–393. 10.1097/MLR.0b013e31815dc5d2 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6. Al Jowf GI, Ahmed ZT, An N, et al. A public health perspective of post-traumatic stress disorder. Int J Environ Res Public Health. 2022;19(11):6474. 10.3390/ijerph19116474 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7. Zalta AK, Held P, Smith DL, et al. Evaluating patterns and predictors of symptom change during a three-week intensive outpatient treatment for veterans with PTSD. BMC Psychiatry. 2018;18(1):242. 10.1186/s12888-018-1816-6 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8. Lande RG, Banks Williams L, Francis JL, Gragnani C, Morin ML. Characteristics and effectiveness of an intensive military outpatient treatment program for PTSD. J Aggress Maltreat Trauma. 2011;20(5):530–538. 10.1080/10926771.2011.588149 [DOI] [Google Scholar]
- 9. Rauch SAM, Yasinski CW, Post LM, et al. An intensive outpatient program with prolonged exposure for veterans with posttraumatic stress disorder: Retention, predictors, and patterns of change. Psychol Serv. 2021;18(4):606–618. 10.1037/ser0000422 [DOI] [PubMed] [Google Scholar]
- 10. Ragsdale KA, Watkins LE, Sherrill AM, Zwiebach L, Rothbaum BO. Advances in PTSD treatment delivery: Evidence base and future directions for intensive outpatient programs. Curr Treat Options Psych. 2020;7(3):291–300. 10.1007/s40501-020-00219-7 [DOI] [Google Scholar]
- 11. Davis AC, Voelkel JL, Remmers CL, Adams JL, McGlynn EA. Comparing Kaiser Permanente members to the general population: Implications for generalizability of research. Perm J. 2023;27(2):87–98. 10.7812/TPP/22.172 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12. Zulman DM, O’Brien CW, Slightam C, Breland JY, Krauth D, Nevedal AL. Engaging high-need patients in intensive outpatient programs: A qualitative synthesis of engagement strategies. J Gen Intern Med. 2018;33(11):1937–1944. 10.1007/s11606-018-4608-2 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13. Gentil L, Grenier G, Vasiliadis H-M, Huỳnh C, Fleury M-J. Predictors of recurrent high emergency department use among patients with mental disorders. Int J Environ Res Public Health. 2021;18(9):4559. 10.3390/ijerph18094559 [DOI] [PMC free article] [PubMed] [Google Scholar]