Normal values of 24-h ambulatory intraluminal impedance combined with pH-metry in subjects eating a Mediterranean diet.
OBJECTIVE
Multichannel intraluminal impedance combined with pH-metry is a novel technique for studying gastro-oesophageal reflux. As refluxes are particularly frequent after meals, we carried out this study in order to assess the impact of a Mediterranean diet on normal values of impedancemetry.


METHODS
Twenty-five Italian healthy subjects (13 men, median age 29 years, range 22-67 years) without reflux symptoms were recruited for this study. They underwent oesophageal 24-h impedance + pH-metry. A Mediterranean diet was given to all subjects on the day of examination and its total energy intake was 9668.5 kJ (2300 kcal).


RESULTS
A total of 1518 refluxes were recorded during 24 h with more upright than recumbent episodes (median 15 versus 0; p<0.01). The median total acid exposure time was 0.5% (range 0-4.2%). Acid and weakly acidic refluxes were equally reported (49% versus 51%). Weakly acidic episodes were more frequent than acid ones during 1-h postprandial periods (68% versus 32%; p<0.0001). Liquid-only and mixed refluxes reached the proximal oesophagus (15 cm above lower oesophageal sphincter) in 42.6% of cases. Median acid clearing time was longer than median bolus clearing time (28 s versus 12 s; p<0.01).


CONCLUSIONS
This study provides normal values of pH-impedancemetry in Italian people eating a Mediterranean diet and are suitable for comparative pathophysiological investigations on reflux patients who have dietary habits similar to those of our country.
Zentilin
P
P
Department of Internal Medicine and Medical Speciality, University of the Studies of Genoa, Viale Benedetto XV, n. 6, 16132 Genoa, Italy.
Iiritano
E
E
Dulbecco
P
P
Bilardi
C
C
Savarino
E
E
De Conca
S
S
Parodi
A
A
Reglioni
S
S
Vigneri
S
S
Savarino
V
V
D000328:Adult; D000368:Aged; D038441:Diet, Mediterranean; D017097:Electric Impedance; D050782:Esophageal pH Monitoring; D005260:Female; D005745:Gastric Acidity Determination; D005764:Gastroesophageal Reflux / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period; D012737:Sex Factors