Effects of High Protein and Low Carbohydrate Smoothie Formulas on Swallowing Capacity in Older Adults: A Cross-Over Study

Abstract

Abstract Background Dysphagia is a common problem in older adults that can lead to nutritional deficiencies. Nutrition support is an alternative nutritional therapy, specifically manufactured for the older individuals at risk of dysphagia. This study aimed to develop four high protein (23-34% energy ratio) and low carbohydrate (25-38% energy ratio) smoothie formulas (white sesame (WS) vs. white sesame and low carbohydrate (WSLC) vs. black sesame and low carbohydrate (BSLC) vs. chicken shitake (CS); 1 kcal/ml) for the older people with dysphagia and to assess their effect on swallowing capacity compared to completed commercial formula (Ensure®). Methods A double-blind, randomized, placebo-controlled cross-over study involved 63 participants aged 65 years or over. Subjects were divided into asymptomatic (n=32, aged 72.9 ± 5.66 year) or symptomatic swallowing difficulty (n=31, aged 75.0 ± 6.48 year) groups based on swallowing screening questionnaires. Swallowing capacity was assessed using Fiberoptic Endoscopic Evaluation of Swallowing (FEES), performed by experienced healthcare professionals, for three drinks (WS, CS vs. Ensure®) in a blinded random sequence. Results Spare retention of a food bolus in each formula had been identified in the asymptomatic (47-66%) and symptomatic (59-71%) groups. WS had fewer premature spills than Ensure® in the symptomatic group, but not in the asymptomatic group (5±0.03 vs. 4.7±0.12, p < 0.05), while CS had fewer premature spills than Ensure®. Conclusions This result suggests that consumption of smoothie drinks, particularly WS (51-350 centipoise), may help reduce the risk and severity of food aspiration in the older people at risk compared to commercial formula (1-50 centipoise). These smoothies may be the alternative completed formulas without additional thickeners for the management and supplementation in older people with dysphagia. Trial registration: Clinical Trial ID: NCT04901182, https://clinicaltrials.gov/ct2/show/NCT04901182 (25/05/2021)