The impact of patients' pre-treatment expectations on immunosuppressive treatment outcomes in myasthenia gravis: A pilot correlational study

Elisa Frisaldi PhD, MSc, Bruno Ferrero MD, Alessandra Di Liberto MD, Diletta Barbiani PhD, Eleonora Maria Camerone PhD, Alessandro Piedimonte PhD, Jan Vollert PhD, MSc, Roberto Cavallo MD, Maurizio Zibetti MD, PhD, Leonardo Lopiano MD, PhD, Aziz Shaibani MD, Fabrizio Benedetti MD

Introduction/Aims The impact of treatment expectations on active treatment outcomes has not been specifically investigated in neuromuscular disorders. We thus explored in myasthenia gravis (MG) the contribution of patients' pre-treatment expectations combined with an immunosuppressant drug on treatment outcomes.

Methods This pilot correlational study involved 17 patients with generalized MG, scheduled to start immunosuppressant azathioprine. At baseline, a healthcare professional administered: (i) the Stanford Expectations of Treatment Scale; (ii) a structured checklist paper form asking patients which side-effects they expected to develop after starting azathioprine, coupled with a standardized framing of statements. Quantitative Myasthenia Gravis (QMG) score and daily dose of concomitant drugs were assessed by neurologists as clinical outcomes. Clinical outcomes and side-effects were re-assessed at 3 and 6 months, and clinical outcomes were monitored at 18 months.

Results Clinically significant improvement in the QMG scores was achieved at 3 or 6 months. The level of state anxiety appeared to act as moderator of pre-treatment negative expectations (strong, positive, indicative correlation, rs=.733, p=.001). The latter were, in turn, associated with the fulfillment of side-effects that patients expected to develop with the new treatment (moderate, positive, indicative correlation, rs=.699, p=.002). No significant correlation emerged between positive and negative expectations.

Discussion Our findings show a very quick clinical response and also suggest that patients' expectations and anxiety contributed to treatment outcomes, highlighting the importance of promoting safety messages and education strategies around newly introduced treatments. Future goals include evaluating a larger cohort that includes a matched control group.

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