– and they carry no increased risk for adverse events, new research shows.
Investigators analyzed data for more than 70,000 patients with schizophrenia and found that, compared with OAs, LAIAs were associated with lower risk for hospitalizations for any cause, hospitalizations for psychiatric disorders, hospitalizations for schizophrenia, and incident suicide attempts.
courtesy University of Hong Kong
Dr. Esther Chan
Among patients treated fully with LAIAs, there were fewer hospitalizations for somatic disorders and cardiovascular diseases and less extrapyramidal symptoms (EPS), compared with those treated fully with OAs. In addition, among those for whom treatment with LAIAs was initiated early, the reduction in these outcome events was greater in comparison with patients for whom treatment was initiated later.
The results “reinforced that LAIAs were associated with a lower risk of hospitalizations, disease relapses, and suicide attempts than OAs, and this association remained during subsequent treatment periods,” wrote the investigators, led by Esther Chan, PhD, Center for Safe Medication Practice and Research, department of pharmacology and pharmacy, University of Hong Kong.
The findings were published online in JAMA Network Open.
Misclassification common
“Current clinical guidelines on the use of LAIAs are derived mainly from randomized clinical trials in which strict inclusion criteria limit generalizability,” the investigators noted. In addition, most of these trials were of “relatively short duration,” so long-term observational studies are “important to establish the safety and effectiveness of LAIAs.”
Moreover, most studies have been based on Western populations, and the findings may not be generalizable to Asian populations, which have been less studied.
Previous studies were also often subject to “misclassification of exposure,” since patients treated with LAIAs alone and those treated concurrently with LAIAs and OAs were categorized together as “LAIA” users and were compared with users of OAs alone, the researchers noted.
To investigate the long-term safety and efficacy of LAIAs, they assessed data from the Clinical Data Analysis and Reporting System, an electronic health records database of the Hong Kong Hospital Authority. They identified 70,396 patients with schizophrenia (52.8% women; mean age, 44.2 years).
The investigators used a self-controlled case series design – “within-individual comparison, based on a case-only approach” – to analyze the data. This model uses incidence rate ratios derived by “comparing the rate of outcomes between exposed and unexposed or reference periods for the same individual.” In this approach, “only people with both the exposure and the outcome are eligible.”
To be included, a patient had to have received at least one OA and LAIA and had to have had at least one outcome event during the observation period of January 2004 or the date of first schizophrenia diagnosis (whichever came later) through December 2019 or death (whichever came first).
The observation period was further subdivided into four periods: a nontreatment period, a period in which OAs were used alone, a period in which LAIAs were used alone, and a period in which a combination of OAs and LAIAs were used together.
Primary outcomes included health care use and disease relapses, such as hospitalizations for psychiatric disorders, hospitalizations for schizophrenia, and incident suicide attempt. Secondary outcomes included hospitalizations for somatic disorders, hospitalizations for cardiovascular diseases, and EPS.