Real-world effectiveness of olanzapine and risperidone in the treatment of schizophrenia in Brazil over a 16-year follow-up period; findings and implications

ABSTRACT

Introduction: Antipsychotics are widely prescribed for patients with schizophrenia. The Brazilian public health system provides these patients free of charge to patients and it is pertinent to evaluate their benefits.

Objective: To evaluate the effectiveness of olanzapine and risperidone in the treatment of patients with schizophrenia in the real-world and assessing risk factors for their discontinuation through a national non-concurrent cohort with 16 years of follow-up.

Methods: Three SUS administrative databases were integrated by deterministic-probabilistic linkage. After patients were matched (1:1) for psychiatric hospitalization, year of receiving the antipsychotic, sex, and age, considering either olanzapine or risperidone at study entry. Kaplan-Meier was used to estimate the cumulative probabilities of discontinuation of treatment and associated factors were identified. Sensitivity analyses were performed.

Results: 3416 pairs of patients were included. Olanzapine had a longer time until discontinuation of treatment (p = 0.021), and risperidone had a higher risk of discontinuation (p = 0.021). Among patients persistent for at least 24 months, there was no statistically significant difference.

Conclusion: Olanzapine demonstrated superior real-world effectiveness over risperidone, in terms of survival and psychiatric hospitalization. This superiority was not sustained in all analyses.

KEYWORDS:

• Antipsychotics
• Brazil
• databases
• olanzapine
• real-world effectiveness
• risperidone
• schizophrenia

Acknowledgments

The authors are grateful for the institutional support of the CCATES/UFMG (SUS Collaborating Centre ‑ Technology Assessment and Excellence in Health, College of Pharmacy, Federal University of Minas Gerais, Brazil).

Author Contributions

Conceptualization, W. B. Barbosa and A.A. Guerra Junior; Data curation, W. B. Barbosa and A.A. Guerra Junior; Formal analysis, W. B. Barbosa, R.M. Gomes and A.A. Guerra Junior; Investigation, W. B. Barbosa and A.A. Guerra Junior; Methodology, W. B. Barbosa, R.M. Gomes and A.A. Guerra Junior; Project administration, W. B. Barbosa and A.A. Guerra Junior; Software, W. B. Barbosa and A.A. Guerra Junior; Supervision, W. B. Barbosa and A.A. Guerra Junior; Validation, W. B. Barbosa, B. Godman and A.A. Guerra Junior; Writing—original draft, W. B. Barbosa, R.M. Gomes, B. Godman and F.d.A. Acurcio; Writing—review and editing, W. B. Barbosa, R.M. Gomes, B. Godman, F.d.A. Acurcio and A.A. Guerra Junior. All authors have read and agreed to the published version of the manuscript.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer declarations

One reviewer has disclosed being a consultant for/received grant/research support and honoraria from, and been on the speakers/advisory board/has received honoraria from talks and/or consultancy from Adamed, Angelini, Ferrer, Janssen-Cilag, Lundbeck, Neuraxpharm, Otsuka, Pfizer and Sanofi, and grants from Spanish Ministry of Health, Instituto de Salud Carlos III. Another reviewer has declared receiving manuscript/speaker’s fees from Astellas, Dainippon Sumitomo Pharma, Eisai, Eli Lilly, Elsevier Japan, Janssen Pharmaceuticals, Kyowa Yakuhin, Meiji Seika Pharma, Mitsubishi Tanabe Pharma, MSD, Nihon Medi-Physics, Novartis, Otsuka Pharmaceutical, Shionogi, Shire, Tsumura, Wiley Japan, and Yoshitomi Yakuhin, and research grants from Eisai, Mochida Pharmaceutical, Meiji Seika Pharma and Shionogi. All other peer reviewers have nothing to declare.

Additional information

Funding

W. B. Barbosa received a PhD scholarship from Financial support from CAPES, in Brazil (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior).