Long-Acting Injectable Antipsychotics in the Geriatric Population: A longitudinal Study.

OBJECTIVE: This study compares demographic, clinical characteristics, and outcomes in older adults on long-acting injectable antipsychotics (LAI-AP) vs. oral antipsychotics (PO-AP). DESIGN: This observational study with a retrospective cohort utilized the electronic medical record's search engine to review charts of geriatric patients on LAI-AP for a two-year period. A convenience sample on PO-AP formed the comparison group. LAI-AP patients were subcategorized into discontinuation and continuation groups. SETTING: Conducted at an urban, psychiatric outpatient clinic, using charts from October 2020 to 2022. PARTICIPANTS: Patients at least 60 years-old with psychotic or mood disorders on antipsychotics for at least 3-months during the study period. MEASUREMENTS: Demographic and clinical variables, including diagnosis, medication type, side effects, medical comorbidities, neurocognitive status, and secondary medications, were collected for both PO-AP and LAI-AP groups. Outcome variables included missed appointments, psychiatric and medical hospitalizations, and emergency room visits. Correlates of discontinuation of LAI-AP were also assessed. RESULTS: LAI-AP had a higher proportion than PO-AP of primary psychotic disorders (87.8% vs. 64.3%). During the study, PO-AP had higher rates of missed appointments (median 18% vs. 13% for LAI-AP) and psychiatric admissions (mean 0.019/month vs. 0.006/month for LAI-AP;); Female sex was a risk factor for discontinuation of LAI-AP (86.7% of discontinuation group vs. 55.2% of continuation group). CONCLUSIONS: The LAI-AP group showed reduced hospitalizations, better treatment engagement, and comparable tolerability to PO-AP. Preliminary data suggests gender may influence LAI-AP discontinuation rates. This study adds to the sparse literature investigating the efficacy and tolerability of LAI-AP in geriatric patients.

Aripiprazole: examining the clinical implications of D2 affinity.

Schizophrenia is a prevalent psychiatric illness, which causes significant financial and social burden on the population overall. The development of second generation antipsychotics, such as Aripiprazole, Risperidone, and Paliperidone, has changed treatment practice for many psychiatrists. Aripiprazole has extremely high binding affinity for the dopamine D2 receptor, which is the receptor thought to be responsible for the antipsychotic effect, although Aripiprazole is not the most potent of the second generation antipsychotics. In theory, Aripiprazole could displace or outcompete other, more potent antipsychotics, prompting decreased antipsychotic effect. We describe a proposed case of this phenomenon, Ms. A. We describe how Aripiprazole may have caused a worsening of psychiatric symptoms by blocking the antipsychotic effects of Paliperidone due to its strong binding affinity for the D2 receptor. Aripiprazole has a high affinity for the D2 receptor, but may have a lesser reduction of psychotic symptoms compared to other antipsychotics. Prescribers should be aware of this potential interaction and carefully consider initiating long-acting injectable forms of Aripiprazole to avoid this phenomenon.