Variability of Oral and Pharyngeal Transit Between Two Consecutive Swallows in Chagas' Disease.

BACKGROUND: Chagas' disease causes dysphagia, regurgitation and retention of food in the esophageal body. Patients have longer pharyngeal clearance, which might be consequent of the involvement of the central nervous system or an adaptation to the esophageal transit impairment. If there is central nervous system involvement by the disease, we expect a larger difference in the oral and pharyngeal phases of swallowing between two consecutive swallows than that seen in controls. Our objective was to evaluate the difference of oral and pharyngeal transit duration between two consecutive swallows in patients with Chagas' disease compared with controls. METHODS: By videofluoroscopy, the duration of oral and pharyngeal transit, pharyngeal clearance, upper esophageal sphincter transit, hyoid movement and oropharyngeal transit was measured in 17 patients with Chagas' disease and 15 asymptomatic volunteers. Each subject swallowed in duplicate and in sequence 5 mL and 10 mL of barium liquid and 5 mL and 10 mL of barium paste boluses. The differences were calculated between the two swallows of each volume and consistency in patients and controls. RESULTS: There were no differences between controls and patients in the values of the differences between the two consecutive swallows, except for the hyoid movement duration of the 5 mL liquid bolus, causing a higher difference in controls than in patients. CONCLUSION: Oral and pharyngeal transit variation between two consecutive swallows is similar between patients with Chagas' disease and controls, which suggests that the longer pharyngeal clearance duration previously described is not a consequence of impairment of the central nervous system control of swallowing.

Effect of gender on swallow event duration assessed by videofluoroscopy.

There are data suggesting that women swallow liquids at a lower flow rate and ingest smaller volumes in each swallow than men. Our objective in this work was to compare swallowing in asymptomatic men and women by videofluoroscopy. We studied 18 men [age = 33-77 years, mean = 61 (10) years] and 12 women [age = 29-72 years, mean = 53 (15) years] who swallowed in duplicate 5 and 10 ml of liquid and paste barium boluses. None of the volunteers had dysphagia, neurologic diseases, or oral, pharyngeal, or esophageal diseases. The videofluoroscopic examination showed that for the 5-ml bolus, women had a longer oropharyngeal transit [liquid: men, 0.63 (0.21) s, women, 0.88 (0.39) s; paste: men, 0.64 (0.35) s, women, 0.94 (0.58) s], longer oral transit [liquid: men, 0.41 (0.21) s, women, 0.59 (0.35) s; paste: men, 0.39 (0.28) s, women, 0.59 (0.42) s], and longer pharyngeal clearance [liquid: men, 0.36 (0.11) s, women, 0.45 (0.16) s; paste: men, 0.42 (0.25) s, women, 0.56 (0.27) s] compared with men (p < 0.05). We conclude that there are differences in swallowing between men and women, with women having a longer oropharyngeal transit than men for a 5-ml bolus.