Table 2 Univariate comparison of pH and Bilitec measurements in gastro-oesophageal reflux disease patients with and without oesophagitis (excluding Barrett’s oesophagus)
No oesophagitisGrade A–Dp Value
Number228164
Age47.4 (1.0)45.7 (1.1)NS
BMI24.4 (0.325.8 (0.4)<0.001
Smoking (%)20%29%<0.05
Alcohol use (%)28%28%NS
Helicobacter positive (%)25.3%11.5%<0.001
Hiatus hernia23%53%<0.001
LOS pressure18.5 (0.6)15.8 (0.6)<0.001
Normal peristalsis89%83%NS
Total time acid reflux
No. of reflux episodes36 (12–63.2)58 (22–104)<0.001
No. of reflux episodes >5 min0 (0–2)2 (0–4)<0.001
% pH<41.7 (0.4–5.1)3.8 (1–8.7)<0.001
Upright position acid reflux
No. of reflux episodes28.5 (9–56.3)41 (15–85)0.005
No. of reflux episodes >5 min0 (0–1)0 (0–2)<0.05
% pH<41.9 (0.5–6.0)3.6 (0.9–9.1)<0.005
Supine position acid reflux
No. of reflux episodes2 (0–9.5)6 (0–24)<0.001
Total reflux episodes >5 min0 (0; 0)0 (0–2)<0.001
% pH<40.1 (0–1.6)1.1 (0–9.8)<0.001
Total time DGOR
No, of reflux episodes11 (2–29)22 (7–48)<0.001
Total reflux episodes >5 min1 (0–4)3 (1–7)<0.001
% bile absorbance >0.142.8 (0.3–12.4)8.8 (2–25.8)<0.001
Upright position DGOR
No. of reflux episodes9.5 (2–25)15 (5–33)0.001
Total reflux episodes >5 min1 (0–3)2 (1–5)<0.001
% bile absorbance >0.143.7 (0.4–13.6)9.4 (1.7–27.8)<0.001
Supine position DGOR
No. of reflux episodes0 (0–2)1 (0–13)<0.001
Total reflux episodes >5 min0 (0–1)0 (0–3)<0.001
% bile absorbance >0.140 (0–5.7)1.2 (0–26)<0.001
  • The periods are subdivided into total time, upright and supine position. The values are given in means (SD) or mean (IQR) and compared with the Mann–Whitney test or χ2 test.

  • BMI, body mass index; DGOR, duodeno-gastro-oesophageal reflux; LOS, lower oesophageal sphincter.