2026 Eastern States Conference

Background: 
Psychiatric disorders are chronic illnesses that often involve recurrent crises, especially when continuity of treatment is disrupted. Antipsychotics play a critical role in preventing relapse, yet poor adherence is affecting nearly 38.7% of patients with psychotic disorder, which significantly increases the likelihood of relapse and rehospitalization. Long-acting injectable antipsychotics (LAIs) help address this challenge by improving adherence and have been associated with lower rates of relapse, hospitalization, and mortality compared with oral formulations.  

Management becomes more complex when mood or substance use disorders co-occur. These comorbidities further reduce adherence, worsen symptoms, and increase inpatient service utilization. Although evidence supports initiating LAIs during inpatient stays, their use in this setting remains limited. Building on these challenges, there is also a notable lack of data on LAIs use among patients with schizophrenia spectrum disorder and co-occurring mood and/or substance use disorders in hospital settings.

Objective: 
To assess the impact of co-occurring mood and/or substance use disorders on readmission rates following LAI treatment among inpatients with schizophrenia spectrum disorders.

Methods:
This retrospective, single-center chart review assessed the use of LAIs in adult patients admitted to a community hospital’s behavioral health unit with a diagnosis of schizophrenia spectrum disorder (SSD). The study aimed to assess the association between co-occurring mood and/or substance use disorders and post-discharge psychiatric outcomes following LAIs treatment.

Electronic medical records were reviewed to collect demographic and clinical variables, including age, sex, race, employment status, psychiatric diagnoses, substance use history, prior psychiatric hospitalizations, involuntary admissions, previous medication adherence, and LAI utilization patterns. Data regarding psychiatric emergency department (ED) visits, 30-day psychiatric readmissions, appropriateness of LAI initiation, and documentation of the next scheduled LAI dose at discharge were also collected.

Patients were stratified into comparison groups based on the presence or absence of co-occurring mood and substance use disorder. Descriptive statistics were used to summarize baseline characteristics and LAI prescribing patterns. Categorical outcomes were compared using odds ratios (ORs) with 95% confidence intervals (CIs), and statistical significance was assessed using p-values, with significance defined as p < 0.05.

The primary outcome was 30-day psychiatric readmission following hospital discharge among patients who received LAI therapy. Secondary outcomes included: (1) subgroup analysis of 30-day psychiatric readmission rates among patients with and without co-occurring mood disorder or SUD; (2) psychiatric ED visits within 30 days post-discharge; (3) appropriateness of LAI initiation during hospitalization; and (4) documentation of the next scheduled LAI dose at discharge.

Patients were included if they were 18 years of age or older, admitted to the inpatient behavioral health unit, carried a diagnosis of SSD, and received treatment with an LAIs during hospitalization. Patients were excluded if they were pregnant or breastfeeding, had a primary diagnosis of substance-induced psychotic disorder without underlying SSD, were admitted primarily for detoxification or medical stabilization without active psychiatric treatment, or had a hospital length of stay less than 24 hours.

Results
A total of 203 patients met study inclusion criteria. The mean age was 39.9 ± 12.5 years, and 52% of patients were female. The cohort was predominantly Black (67%). Socioeconomic instability was common, with 96% of patients unemployed, 20% experiencing homelessness, and 28% lacking a documented high school completion. Clinically, patients had a mean illness duration of 8 years, 55% had a history of ≥7 prior psychiatric hospitalizations, and 57% had involuntary admissions. Among LAIs prescribed, haloperidol decanoate was the most frequently used agent (49%), followed by paliperidone palmitate (22.5%).

The overall 30-day psychiatric readmission rate among patients receiving LAIs was 5.9% (12/203).
Patients with co-occurring SUD demonstrated a numerically higher readmission rate compared with those without SUD (9.3% vs 2.8%; OR 3.51, 95% CI 0.92–13.37; p = 0.052), suggesting a trend toward significance. In contrast, no statistically significant difference in readmission was observed between patients with and without mood disorders (4.4% vs 9.0%; OR 0.47, 95% CI 0.14–1.51; p = 0.197).

Rates of psychiatric ED visits within 30 days post-discharge were comparable between groups; SUD vs No SUD (28.9% vs 31.1%; OR 0.89, 95% CI 0.49–1.63; p = 0.725), and mood disorders vs No mood disorders (29.4% vs 31.3%; OR 0.91, 95% CI 0.48–1.72; p = 0.778).

Among patients initiated on LAIs during hospitalization (n = 149), initiation was considered appropriate in 58.4% of cases, while 41.6% were categorized as inappropriate. Documentation of the next scheduled LAI dose at discharge was associated with lower readmission rates compared with cases lacking documentation (1.3% vs 8.7%; OR 0.14, 95% CI 0.018–1.11; p = 0.063), although this finding should be interpreted cautiously given the small sample size.

Conclusion
Among hospitalized patients with schizophrenia spectrum disorders receiving LAI antipsychotics, the overall 30-day psychiatric readmission rate was low (5.9%). Co-occurring mood disorders were not associated with increased readmission risk, while patients with co-occurring substance use disorders demonstrated a trend toward higher readmission rates, suggesting a subgroup that may benefit from enhanced post-discharge monitoring and support.
This study also identified important practice gaps related to LAI management, including inconsistent appropriateness of LAI initiation and inadequate documentation of follow-up injection plans at discharge. Improved discharge planning, standardized LAI initiation protocols, and stronger outpatient care coordination may further optimize outcomes in this high-risk population. Larger prospective studies are warranted to better evaluate the impact of co-occurring psychiatric comorbidities on outcomes associated with LAI treatment in hospital settings.

Citations:  

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