Clinical Summary
Clinical Summary: From Hospital to Outpatient Care After Long-Acting Injectable Antipsychotic Initiation in Bipolar Disorder: Nationwide Evidence From Taiwan
Patients with bipolar disorder often relapse when daily medication adherence breaks down, leading to emergency visits, hospitalization, and disrupted continuity of care. This study asks a practical question clinicians face every day: after starting a second-generation long-acting injectable antipsychotic, does psychiatric care actually shift away from crisis services and toward planned outpatient follow-up?
Design
a nationwide, retrospective mirror-image study
N
2,937 first-time SGA-LAI users with BD
Population
individuals with BD (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code 296.4–296.7; International Statistical Classification of Diseases and Related Health Problems, Tenth Revision [ICD-10] code F31) who received LAI antipsychotics
Duration
12 months before and 12 months after the index SGA-LAI initiation date
Key Findings
- Among stable users (n=500), psychiatric outpatient visits increased from 10.43 to 15.90 (P < .001), while psychiatric ED visits decreased from 0.28 to 0.08 (P < .001), admissions decreased from 2.96 to 1.92 (P < .001), and LOS decreased from 86.21 to 60.20 days (P = .0048) in the 12 months after SGA-LAI initiation.
- Among non-stable users (n = 2,419), psychiatric outpatient visits increased from 8.98 to 13.49 (P < .001), while ED visits decreased from 0.29 to 0.12 (P < .001), admissions decreased from 2.45 to 2.01 (P = .006), and LOS decreased from 67.04 to 51.64 days (P < .001).
- Stable users had large increases in outpatient treatment spending after initiation, with outpatient drug costs rising from US$356.16 to US$2,860.08 (P < .001) and outpatient medical expenditures rising from US$670.95 to US$3,618.45 (P < .001).
- Inpatient burden fell after initiation in both groups: in stable users, inpatient medical expenditures decreased from US$7,405.35 to US$3,767.12 (P < .001); in non-stable users, inpatient medical expenditures decreased from US$6,014.24 to US$3,836.22 (P < .001).
- Reduced acute-care use did not clearly translate into short-term overall savings: total medical costs in stable users decreased from US$8,112.19 to US$7,394.73 (P =.188), while total drug costs increased from US$1,405.48 to US$3,631.88 (P < .001); in non-stable users, total medical costs decreased from US$6,593.09 to US$5,553.65 (P < .001), and the between-group difference in total medical cost change was not statistically significant (P = .584).
Clinical Bottom Line
After second-generation long-acting injectable antipsychotic initiation in bipolar disorder, psychiatric service use shifted from emergency and inpatient settings toward outpatient follow-up. In practice, LAIs function as a continuity-of-care strategy, but clinicians should not expect reduced acute-care use to guarantee short-term total medical cost savings.
Practice Implications
- Consider long-acting injectable antipsychotics when the main clinical goal is to stabilize follow-up and reduce on-off medication cycling, especially in patients with recurrent relapse or unreliable oral adherence.
- Set expectations that successful LAI implementation will likely mean more scheduled outpatient contact and higher outpatient drug spending, not simply fewer total health care costs in the first year.
- Interpret 12-month stable use as sustained engagement with injection-based care rather than proof of superior pharmacologic efficacy; in this study, stable use required at least 12 injections for Abilify Maintena and Invega Sustenna, at least 24 injections for Risperdal Consta, and at least 4 injections for Invega Trinza.
- Be cautious about overattributing reduced hospitalization to medication effect alone, because when the ±30-day index window was excluded, the apparent reductions in inpatient admissions, length of stay, and inpatient expenditures among non-stable users were not robust.
