Quantifying Post-Swallow Residue in Healthy Aging

Abstract

Purpose Reports are mixed on whether post-swallow residue increases with age. This question was investigated using a quantitative measure of residue in a large cohort of healthy adults. It was hypothesized that post-swallow residue would differ between younger and older healthy adults, and significantly increase in individuals ≥ 80 years. Method In this observational study, 275 healthy volunteers aged 18–99 years underwent videofluoroscopic swallow studies. Post-swallow residue was quantified using the Bolus Clearance Ratio (BCR) for a 20-ml thin liquid barium bolus and 3-cm 3 barium paste bolus. Number of swallows required per bolus and aspiration were also determined as additional markers of swallow efficiency and safety. Results Most BCR values were low, < 0.05 (< 5% of the bolus) for 78% of 20 ml and 66% of paste swallows. BCR values were significantly larger in healthy older adults, although, clinically, the differences are arguably minimal (differences in mean BCR values between age groups: 20 ml: 0.01 [1%]; paste: 0.03 [3%]). For 20 ml, 56% of adults ≥ 80 years performed multiple swallows (oral residue and dose metering) versus 9% of adults 18–39 years. One aspiration event was observed. Conclusions Post-swallow residue was slightly increased in older adults; many individuals ≥ 80 years performed more than one swallow per bolus to achieve this similar level of clearance. This suggests a reduction in swallow efficiency with age without compromising swallow safety. Post-swallow residue that poses a risk of airway invasion should be considered a sign of swallowing dysfunction, not healthy aging.

A Novel Quantitative Measure of Pharyngeal Shortening

“…Since the California videos pre‐dated IDDSI, the barium was not tested but was presumed to be thin (Barosperse diluted to 45% concentration). Although the concentration of the California barium was slightly stronger (45% vs. 32% w/v), results between the research sites have been previously analyzed and not found to differ significantly, t (216.86) = 0.29, p = 0.77, 8 and were therefore merged.…”

“…Other measures included the Penetration-Aspiration Scale (PAS) 9 -an ordinal scale of depth and response to airway invasion and pharyngeal timing and displacement parameters as described by Leonard and colleagues. 6,8,10,11 including the following: pharyngeal constriction ratio (PCR), pharyngoesophageal segment (PES) opening (PESmax), maximum hyoid displacement (HMax), hyoid-larynx displacement (HL) and Bolus Clearance Ratio (BCR).…”

Spotlight on Older Adults in Swallowing Research

“…Consistently reported age effects include increased swallow reaction, bolus transit, and UES opening times, and pressure changes at the UES and LES [8,10,11]. Swallowing compensatory strategies may be spontaneously adopted, such as dose metering (dividing a bolus in the mouth so that the quantity swallowed is smaller), clearing oral residue, and taking smaller sips or mouthfuls [12].…”