Table 1 Prevalences of abnormal gastro-oesophageal reflux (pH testing) and of delayed gastric emptying (nuclear medicine study)

Lung disease group	Study	Patient population	No of patients	Manometry	Abnormal distal reflux (%)	Abnormal proximal reflux (%)	Delayed gastric emptying	Comment
Usual interstitial pneumonia	Tobin 199815	IPF Clinic	17	Selected patients	88	71%		Manometry not used
	Raghu 200617	IPF Clinic	65	Yes	76	63		Some subjects taking PPIs and pH probe placement varied
	Salvioli 200618	IPF Clinic	18	Selected patients	67			Manometry not used
	Sweet 200719	Pre-transplant	30	Yes	67	30
Cystic fibrosis	Ledson 199826	CF Clinic	10	Yes	80			Patients with symptoms selected
	Button 200523	Pre-transplant	11	No	91	Undefined		Some subjects taking PPIs, 1 patient s/p fundoplication
	Button 200523	Post-transplant	13	No	85	Undefined		Some subjects taking PPIs, 1 patient s/p fundoplication
	Bodet-Milin 200627	Pre-transplant	30				67%
Connective tissue disease	Johnson 198910	Rheumatology Clinic	13	Yes	54	Undefined
	Bassotti 199729	Dermatology Clinic	78	Yes	78			Acid suppression not withheld prior to study
	Gasper 2007*	Transplant Clinic	23	Yes	83	30	6 of 8 (75%)
COPD	Andersen 198930	COPD Clinic	55	Yes	49
COPD	Casanova 200431	COPD Clinic	42	Yes	62
Pre-lung transplant	Cantu 200540	Transplant Clinic	36	Yes	63			PPI withheld for 5 days
	D’Ovidio 200524	Transplant Clinic	78	Yes	32	20	13 of 27 (44%)	PPI withheld for 5 days
	Sweet 200625	Transplant Clinic	109	Yes	68	37
Post-lung transplant	Cantu 200540	Transplant Clinic	167	Yes	76			PPI withheld for 5 days
	Berkowitz 199546	Transplant Clinic	38				24%	Studied both lung and heart–lung transplant patients
	D’Ovidio 200645	Transplant Clinic	50, 30	Yes	26, 50	0–14 and 10–17	39 of 43 (91%)	Patients studied at 2 time points: 3 and 12 months after transplant

*Unpublished data.
COPD, chronic obstructive pulmonary disease; IPF, idiopathic pulmonary fibrosis; PPIs, proton pump inhibitors; s/p, status post.