Carbonated beverages initiate the swallowing reflex earlier than water and have a shorter pharyngeal transit time. However, the effects of carbonation in thickened beverages of the same flavor on swallowing dynamics have not been reported. Therefore, we investigated the effects of thickened carbonated beverages on swallowing in patients with dysphagia by comparing the swallowing dynamics between thickened carbonated and thickened non-carbonated beverages. We enrolled 38 patients with dysphagia and divided them into two groups. Thickened carbonated and thickened non-carbonated beverages were used. Videoendoscopic swallowing evaluations were performed. Aspiration, penetration, pharyngeal residue, and initiation position of the swallowing reflex were evaluated. The reduction in the amount of residue in both the vallecula (p = 0.007) and pyriform sinus (p = 0.004) was greater after ingestion of thickened carbonated cola than thickened non-carbonated cola. The onset of the swallowing reflex was significantly earlier after ingestion of thickened carbonated cola than thickened non-carbonated cola (p = 0.007). There were no significant differences in the extent of penetration. Thickened carbonated beverages positively affected swallowing compared with thickened non-carbonated beverages. Thus, the use of thickened carbonated beverages may be helpful for patients with dysphagia.

1. Haruka Tohara, Professor
   
   Department of Dysphagia Rehabilitation,
   Graduate School of Medical and Dental Sciences,
   Tokyo Medical and Dental University(TMDU)
   E-mail:h.tohara.swal(at)tmd.ac.jp
   
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