Table 1.

Demographic and health characteristics of respondents with IBS-D (diagnosed and undiagnosed) and controls

	Total n = 66,491	IBS-D, diagnosed n = 842	IBS-D, undiagnosed n = 260	Controls n = 65,389	p-value
Age, mean (SD)	48.72 (16.61)	50.39 (15.79)a	43.05 (14.40)b	48.72 (16.62)c	<0.001
Charlson Comorbidity Index, mean (SD)	0.42 (0.99)	0.72 (1.23)a	0.75 (1.50)a	0.41 (0.98)b	<0.001
Female, n (%)	33377 (50.2)	510 (60.6)a	169 (65.0)a	32698 (50.0)b
Race/ethnicity, n (%)					<0.001
Non-Hispanic White	47700 (71.7)	712 (84.6)a	180 (69.2)b	46808 (71.6)b
Non-Hispanic Black	7857 (11.8)	31 (3.7)a	28 (10.8)b	7798 (11.9)b
Hispanic	5603 (8.4)	49 (5.8)a	27 (10.4)b	5527 (8.5)b
Other ethnicity	5331 (8.0)	50 (5.9)a	25 (9.6)b	5256 (8.0)b
Education, n (%)					0.069
< 4-year degree	39657 (59.6)	496 (58.9)a	173 (66.5)b	38988 (59.6)a
≥ 4-year degree	26834 (40.4)	346 (41.1)a	87 (33.5)b	26401 (40.4)a
Annual household income, n (%)					0.008
< $25 k	12750 (19.2)	161 (19.1)a	65 (25.0)b	12524 (19.2)a
$25–50 k	17775 (26.7)	215 (25.5)a	80 (30.8)a	17480 (26.7)a
$50–75 k	13037 (19.6)	189 (22.4)a	54 (20.8)a,b	12794 (19.6)b
≥ $75 k	17369 (26.1)	214 (25.4)a	46 (17.7)b	17109 (26.2)a
Declined to answer	5560 (8.4)	63 (7.5)a	15 (5.8)a	5482 (8.4)a
Labor force participation, n (%)					0.424
Yes	35636 (53.6)	433 (51.4)a	142 (54.6)a	35061 (53.6)a
No	30855 (46.4)	409 (48.6)a	118 (45.4)a	30328 (46.4)a
Body mass index, n (%)					<0.001
Underweight (<18.5)	1231 (1.9)	11 (1.3)a	3 (1.2)a	1217 (1.9)a
Normal weight (18.5–24.99)	20894 (31.4)	228 (27.1)a	76 (29.2)a,b	20590 (31.5)b
Overweight (25–29.99)	21347 (32.1)	243 (28.9)a	68 (26.2)a	21036 (32.2)b
Obese (≥30)	21265 (32.0)	341 (40.5)a	111 (42.7)a	20813 (31.8)b
Unknown	1754 (2.6)	19 (2.3)a	2 (0.8)a	1733 (2.7)a

For pairwise comparisons, values in the same row not sharing the same subscript letter (a, b, or c) are significantly different at p < 0.05

Abbreviations: IBS-D irritable bowel syndrome with diarrhea, SD standard deviation