Is obesity associated with gastropharyngeal reflux disease?

Table 1 Patient profiles and the endoscopic findings according to the body mass index

	Body mass index (kg/m2)			P value
	< 23 (n = 344)	23-25 (n = 231)	>25 (n = 194)
Age (yr, mean ± SEM)	48.4 ± 0.7	51.5 ± 0.7	53.8 ± 0.8	< 0.001
Gender (%)				0.077
Men	123 (35.8)	104 (45.0)	80 (41.2)
Women	221 (64.2)	127 (55.0)	114 (58.8)
Alcohol intake Smoking	66 (19.2)	50 (21.6)	55 (28.4)	0.048
	42 (12.2)	31 (13.4)	33 (17.0)	0.295
Indication for pH monitoring (%)				0.210
Globus	156 (45.3)	100 (43.3)	86 (44.3)
Hoarseness	76 (22.1)	60 (26.0)	54 (27.8)
Coughing	54 (15.7)	46 (19.9)	26 (16.4)
Others1	58 (16.9)	25 (10.8)	28 (14.4)
Endoscopic findings (%)
Reflux esophagitis2	32/291 (11.0)	19/204 (9.3)	32/166 (19.3)	0.009
Hiatal Hernia	15/291 (5.2)	19/204 (9.3)	12/166 (7.2)	0.199
Endoscopically suspected esophageal metaplasia	18/291 (6.2)	18/204 (8.8)	16/166 (9.6)	0.348

¹Other indications were halitosis, throat clearing and laryngeal pathology such as vocal polyp;

²Los Angeles classification grade.

Table 2 Results of esophageal manometry according to the body mass index (mean ± SE)

	Body mass index (kg/m2)			P value
	< 23 (n = 344)	23-25 (n = 231)	> 25 (n = 194)
Proximal esophageal amplitude (mmHg)	59.6 ± 1.7	60.1 ± 2.0	62.1 ± 2.4	0.650
Distal esophageal amplitude (mmHg)	75.1 ± 2.0	79.5 ± 2.9	90.2 ± 3.1a	< 0.001
LES pressure (mmHg)	20.9 ± 0.4	20.3 ± 0.5	20.6 ± 0.6	0.711
LES length (cm)	3.3 ± 0.0	3.3 ± 0.0	3.3 ± 0.0	0.636
Peristalsis (%)	96.5 ± 0.6	95.2 ± 0.8	96.1 ± 0.7	0.640
Manometric diagnosis				0.440
Normal	143	80	84
Diffuse esophageal spasms	4	1	1
Nutcracker esophagus	16	15	17
Hypertensive LES	2	2	2
Ineffective esophageal motility	103	74	52
Nonspecific esophageal motility disorder	76	59	38

Post hoc analysis using Tukey's HSD:

^aP < 0.05 vs BMI < 23 and BMI 23-25.

Table 3 Results of ambulatory 24-h dual probe pH monitoring according to the body mass index (mean ± SE)

		Body mass index (kg/m2)			P value
		< 23 (n = 344)	23-25 (n = 231)	> 25 (n = 194)
Proximal probe
Time pH < 4 (total)		0.7 ± 0.2	0.5 ± 0.1	0.5 ± 0.1	0.502
Time pH < 4 (upright)		0.8 ± 0.1	0.7 ± 0.1	0.8 ± 0.1	0.809
Time pH < 4 (supine)		0.6 ± 0.3	0.2 ± 0.1	0.1 ± 0.0	0.245
No. of reflux episodes		11.1 ± 1.8	8.4 ± 1.0	9.5 ± 1.1	0.452
Distal probe
Time pH < 4 (total)		2.7 ± 0.2	3.7 ± 0.5	3.8 ± 0.3a	0.038
Time pH < 4 (upright)		3.9 ± 0.3	5.8 ± 0.9	5.6 ± 0.5a	0.021
Time pH < 4 (supine)		1.4 ± 0.3	2.2 ± 0.6	2.1 ± 0.3	0.211
No. of reflux episodes		39.1 ± 2.3	46.1 ± 3.1	59.4 ± 4.9ab	< 0.001
No. of reflux episodes ≥ 5 min		1.6 ± 0.2	1.6 ± 0.2	2.0 ± 0.3	0.477
Longest reflux episode (min)		8.6 ± 1.3	11.3 ± 2.4	11.1 ± 0.9	0.385
DeMeester composite score		11.0 ± 0.9	14.5 ± 1.7	15.7 ± 1.2a	0.016

Post hoc analysis using Tukey's HSD:

^aP < 0.05 vs BMI < 23;

^bP < 0.05 vs BMI 23-25.

Table 4 Association of body mass index with gastroesophageal reflux disease and gastropharyngeal reflux disease, defined by ambulatory pH monitoring

	Body mass index (kg/m2)			P value
	< 23 (n = 344)	23-25 (n = 231)	> 25 (n = 194)
Gastroesophageal reflux disease (%)				0.001
Absent	203 (59.0)	121 (52.4)	82 (42.3)
Present	141 (41.0)	110 (47.6)	112 (57.7)
Gastropharyngeal reflux disease (%)				0.162
Absent	143 (41.6)	103 (44.6)	69 (35.6)
Present	201 (58.4)	128 (55.4)	125 (64.4)

Table 5 Multivariable analysis: unadjusted and adjusted analyses for relationships of the body mass index with gastroesophageal reflux disease and gastropharyngeal reflux disease, defined by ambulatory pH monitoring

		Body mass index (kg/m2)
		< 23	23-25	> 25
Gastroesophageal reflux disease
Unadjusted OR (95 CI)		1	1.3 (0.9-1.8)	2.0 (1.4-2.8)
Adjusted OR (95 CI)1		1	1.2 (0.8-1.7)	1.9 (1.3-2.9)
Gastropharyngeal reflux disease
Unadjusted OR (95 CI)		1	0.9 (0.6-1.2)	1.3 (0.9-1.9)
Adjusted OR (95 CI)1		1	0.9 (0.6-1.3)	1.1 (0.8-1.7)

¹Adjusted for age, sex, alcohol intake and smoking.