Introduction: The study aims to evaluate and rank cholinesterase inhibitors, the NMDA antagonist memantine, anti-amyloid monoclonal antibodies, and non-drug modalities with respect to cognitive outcomes, functional status, neuropsychiatric symptoms, and tolerability. Methodology: We registered a protocol in PROSPERO and searched PubMed/MEDLINE, Embase, CENTRAL, Web of Science, trial registries, and gray literature through June 2025. Eligible randomized phase II/III trials in adults with clinically diagnosed AD were screened in duplicate. Data on interventions, comparators, outcomes (e.g., MMSE, ADAS-Cog, CDR-SB), and adverse events were extracted. Risk of bias was assessed using Cochrane RoB 2. A Bayesian random-effects NMA synthesized 125 trials (n > 30,000), estimating standardized Mean Differences (SMDs) with 95% Credible Intervals (CrIs). Heterogeneity (I²) and inconsistency (design-by-treatment, node-splitting) were evaluated. Results: The network was well connected, with low-to-moderate heterogeneity (global I² = 38.5%) and no significant inconsistency (p = 0.48). Cognitive training (SMD = 0.45; 95% CrI 0.30-0.60; SUCRA 92%), aerobic exercise (SMD = 0.55; 95% CrI 0.35-0.75; SUCRA 87%), and galantamine (SMD = 0.40; 95% CrI 0.22-0.58; SUCRA 84%) ranked highest versus placebo. Donepezil (SMD = 0.21; 95% CrI 0.11-0.30; SUCRA 78%) and memantine (SMD = 0.24; 95% CrI 0.13-0.35; SUCRA 72%) showed modest benefits. Discussion: Risk-of-bias ratings were low in 37% of trials, some concerns in 48%, and high in 15%. Subgroup analyses confirmed greater cholinesterase inhibitor efficacy in mild AD and superior memantine effects in moderate-to-severe disease. Conclusion: Non-pharmacological interventions demonstrated short-term cognitive benefits primarily in mild Alzheimer’s disease populations and should be interpreted as adjunctive symptomatic strategies rather than direct substitutes for pharmacological therapy.
Li et al. (Tue,) studied this question.