Efficacy of swallowing rehabilitative therapies for adults with dysphagia: a network meta-analysis of randomized controlled trials

Dysphagia leads to poor swallowing function and high risk of aspiration; swallowing rehabilitative therapies including jaw exercises, tongue exercises, chin tuck against resistance (CTAR), Shaker exercises, effortful swallow training (EST), traditional dysphagia therapy (TDT), and respiratory muscle training (RMT) including inspiratory muscle strength training (IMST) and expiratory muscle strength training (EMST) are a crucial part of dysphagia rehabilitation. However, limited evidence exists on the comparative efficacy of swallowing rehabilitative therapies in adults with dysphagia. This is the first network meta-analysis (NMA) to investigate the comparative efficacy of swallowing rehabilitative therapies for adults with dysphagia. Web of Science, Embase, CINAHL, Cochrane Library, and PubMed were comprehensively searched until September, 2024. The Frequentist NMA model was performed in R-Software presenting standardized mean differences with corresponding 95% confidence interval (95% CI) for swallowing function and aspiration. Cochrane Q, τ2, and I2 statistics estimated heterogeneity and full design-by-treatment interaction random-effects and node-splitting models determined transitivity. Ranking of the swallowing rehabilitative therapies used the netrank function. The search yielded 7697 studies from which 25 randomized controlled trials with 1020 adults with dysphagia were included. The study findings revealed that CTAR + TDT (SMD = 3.44 [95% CI 2.42, 4.47]), EMST + TDT (SMD = 2.92 [95% CI 1.59, 4.25]), Shaker + TDT (SMD = 2.83 [95% CI 1.81, 3.84]), JE + TDT (SMD = 2.52 [95% CI 1.21, 3.83]), TE + TDT (SMD = 2.19 [95% CI 1.26, 3.12]), RMT + TDT (SMD = 2.14 [95% CI 1.36, 2.93]), and TDT (SMD = 1.92 [95% CI 1.42, 2.42]) showed very-large to huge effect in improving swallowing function. CTAR + TDT (0.93) demonstrated superior improvements for better swallowing function. Additionally, CTAR + TDT (SMD = − 1.82 [95% CI − 2.89, − 0.75]), Shaker + TDT (SMD = − 1.32 [95% CI − 2.36, − 0.27]), EMST (SMD = − 1.23 [95% CI, − 2.01, − 0.45]), and EMST + TDT (SMD = − 1.10 [95% CI − 2.15, − 0.04]) revealed very-large to large effect in preventing aspiration. CTAR + TDT (0.96) and Shaker + TDT (0.76) demonstrated superior improvements for reduced aspiration. The combination of swallowing rehabilitative therapies including CTAR + TDT and Shaker + TDT offers a more comprehensive approach for dysphagia management in adults. Study registration is PROSPERO: CRD42022321345.