Hypotheses

Nascimento, WV. Differences in timing between functional swallows of older adults at risk for dysphagia and healthy older and young adults. 96p. [Thesis] Ribeirão Preto Medical School-USP. Ribeirão Preto -SP, 2018. Introduction: As with other functions, the aging process can cause changes in swallowing, even in asymptomatic individuals. Purpose: 1. To determine whether timing measures for swallows from healthy older adults differ from comparison measures for healthy young adults. 2. To determine whether timing measures for functional swallows from older adults at risk of dysphagia differ from comparison measures for healthy older adults. 3 To determine whether differences in timing explain the occurrence of transient penetration of material into the airway (Penetration-Aspiration Scale scores of 2) in any of these groups. Method: Duplicate blinded ratings were obtained for swallows of 20%w/v thin liquid barium collected under videofluoroscopy at 30 frames/s from 17 healthy older adults, aged 60-84 (12 women). Swallows were compared to data from a retrospective dataset collected in 20 healthy young adults aged 2245 (10 women) and functional swallows (Penetration-Aspiration Scale scores <3) of 11 older adults at risk for dysphagia, aged 62-87 (3 women). Eight timing measures were studied, including parameters related to swallow response, bolus transit, laryngeal vestibule closure and upper esophageal sphincter (UES) function. We used linear mixed model repeated measures ANOVAs to explore the hypothesis that swallow timing measures would be longer in the older adults than in young adults, and even longer in the older adults at risk for dysphagia. Results: Consistent with the hypotheses, significantly longer swallow reaction time, UES opening (UESO) duration, the interval from laryngeal vestibule closure (LVC) to UESO (p<0.01) and the interval following UESO to maximum pharyngeal constriction (MPC) were seen in the healthy older participants compared to the young healthy controls. Furthermore, a significantly longer interval from the onset of hyoid movement to UES opening, and longer laryngeal vestibule closure reaction time (LVCRT), (p<0.01) were seen in the older participants at risk of dysphagia in comparison with healthy older adults. Also, this group presented longer intervals from LVC to UES opening and from maximum pharyngeal constriction to UES closure. For both the healthy young group and the healthy elderly group, in cases where transient penetration of material into the laryngeal vestibule was seen, laryngeal vestibule closure reaction time was longer and laryngeal vestibule closure occurred late, after UES opening. For both the healthy elderly group and elderly at risk of dysphagia, when penetration was observed, a shorter interval from hyoid onset to upper esophageal sphincter opening was seen. Also, laryngeal vestibule closure was late and there was a longer LVC to UESO interval when penetration occurred. Finally, laryngeal vestibule closure duration was shorter in case of penetration in the elderly group at risk of dysphagia Conclusions: Longer swallow timing measures, in general, distinguish swallows in healthy older adults from swallows in young healthy adults, and in older adults at risk of dysphagia from healthy older adults. In cases of transient penetration, laryngeal vestibule closure was delayed.