Evaluating the Effects of Rivastigmine on Decision-Making in Patients with Mild Cognitive Impairment by Cambridge Neuropsychological Test Automated Battery (CANTAB); A Randomized, Double-Blind, Placebo-Controlled Trial

Background: Decision-making is a complex process, and most studies showed that patients with mild cognitive impairment (MCI) make worse decisions than healthy people. Objectives: This study aims to evaluate the effect of rivastigmine on the decision-making of MCI patients using the Cambridge Neuropsychological Test Automated Battery (CANTAB) tests. Methods: The study was conducted at the Roozbeh Hospital neurology clinic, and 30 patients with mild cognitive impairment over 40 years old were randomly recruited to receive rivastigmine or placebo twice daily for 12 weeks. The initial dose of rivastigmine or placebo was 1.5 mg twice daily and was increased to 3 mg twice daily per patient compliance. A CANTAB test was conducted before and following the intervention. Results: The mean age of patients in the rivastigmine group was 58.93 ± 10.88, and in the placebo group was 59.33 ± 10.34. The median MMSE (Mini-Mental State Examination) was 26 (IQR = 25 - 26) in both groups. Patients in the rivastigmine group showed significant differences in all subgroup tests of CGT, IST, and SST except in risk adjustment in the CGT test, discrimination in the IST test, and median correct RT on the go trial and SSRT in the SST test. The most commonly reported adverse effects were gastrointestinal complications. Conclusions: According to the results, rivastigmine significantly improved the primary decision-making outcomes in comparison with placebo.