Severity of gastroesophageal reflux disease influences daytime somnolence: A clinical study of 134 patients underwent upper panendoscopy

Table 1 Descriptive statistics of the total study population

Variable	Minimum	Maximum	Mean	SD
Age (yr)	17.00	83.00	52.940	16.752
Male	0	1	0.485	-
BMI	17.54	43.94	26.420	5.133
GERD 0	0	1	0.179	-
GERD I	0	1	0.216	-
GERD II	0	1	0.418	-
GERD III	0	1	0.097	-
GERD IV	0	1	0.089	-
EPWORTH	1.00	24.00	7.440	4.226
		n = 134

Note: The mean values of the dichotomous variables (with cases taking values 0 or 1) refer to frequencies and thus the standard deviation is not an applicable measure for them.

Table 2 Measures of daytime somnolence by GERD groups

GERD	n	EPWORTH index	“Abnormal” EPWORTH
		Mean (Std. dev.)	> 8 Frequency
GERD 0	24	6.708 (4.639)	0.291
GERD I	29	7.172 (4.036)	0.379
GERD II	56	7.393 (3.706)	0.464
GERD III	13	10.769 (5.890)	0.769
GERD IV	12	6.166 (2.588)	0.500
Total sample	134	7.440 (4.226)	0.447

Notes: 1. The equality of the mean values for the Epworth in-dices could be rejected at 5% significance level on the basis of the Student t-tests for the following pairs of GERD groups: GERD III vs GERD II, GERD III vs GERD I, GERD III vs GERD 0, and GERD III vs GERD IV. 2. The Pearson chi-square tests for the frequencies of “abnormal” Epworth indices indicated significant differences at 5% critical value in the case of the following 2x2 tables : GERD III vs GERD II, GERD III vs GERD I, GERD III vs GERD 0.

Table 3 Linear regression and dependent variable: Epworth index

	Reference: GERD 0			Reference: GERD III
	& control variables			& control variables			Reference: GERD 0			Reference: GERD III
	B	t-stat	Signif	B	t-stat	Signif	B	t-stat	Signif	B	t-stat	Signif
Constant	5.210	2.370	0.019	8.743	3.653	0.000	6.708	7.748	0.000	10.769	9.155	0.000
GERD 0				-3.534	-2.410	0.018				-4.061	-2.780	0.006
GERD I	0.503	0.433	0.666	-3.031	-2.125	0.036	0.464	0.397	0.692	-3.597	-2.541	0.012
GERD II	0.635	0.610	0.543	-2.899	-2.178	0.031	0.685	0.662	0.510	-3.376	-2.586	0.011
GERD III	3.534	2.410	0.018				4.061	2.780	0.006
BMI	0.092	1.254	0.212	0.092	1.254	0.212
NEM	-0.002	-0.003	0.998	-0.002	-0.003	0.998
AGE50	-1.557	-1.999	0.048	-1.557	-1.999	0.048
n =122

Table 4 Logistic regression , dependent variable: “abnormal” EPWORTH

	Reference: GERD 0				Reference: GERD III
	& control variables				& control variables				Reference: GERD 0				Reference: GERD III
	B	Wald-stat	Signif	Oddsratio	B	Wald-stat	Signi	Oddsratio	B	Wald-stat	Signif	Odds ratio	B	Wald-stat	Signif	Oddsratio
Constant	-0.399	0.153	0.695		-0.399	0.153	0.695		-0.079	0.119	0.729		-0.079	0.119	0.729
GERD		6.547	0.087			6.547	0.087			7.452	0.058			7.452	0.058
GERD 0					-1.996	6.126	0.013	0.136					-2.091	6.887	0.008	0.124
GERD I	0.404	0.461	0.497	1.498	-1.592	4.234	0.039	0.204	0.394	0.447	0.503	1.484	-1.696	4.963	0.025	0.183
GERD II	0.704	1.748	0.186	2.023	-1.292	3.118	0.077	0.275	0.744	2.025	0.154	2.104	-1.347	3.592	0.058	0.260
GERD III	1.996	6.126	0.013	7.361					2.091	6.887	0.008	8.095
BMI	0.023	0.406	0.523	1.023	0.023	0.406	0.523	1.023
NEM	-0.166	0.174	0.675	0.847	-0.166	0.174	0.675	0.847
AGE50	-0.408	1.112	0.291	0.664	-0.408	1.112	0.291	0.664
n=122