Table 1

Participant characteristics and distribution in the control and IBS groups (n=2816)

Control (n=1124)IBS (n=1692)P value
Age, n, median (25th–75th percentile)40 1124 (34–50)42 1692 (34–53)0.01
Gender, n (%)
 Female724(64.41)1290 (76.24)<0.01
 Male400 (35.59)402 (23.76)<0.01
Region of the USA, n (%)
 Midwest183 (16.28)289 (17.08)0.61
 Northeast202 (17.97)342 (20.21)0.15
 South282 (25.09)478 (28.25)0.07
 West457 (40.66)583 (34.46)<0.01
Race, n (%)
 Caucasian/European/American606 (53.91)1011 (59.75)<0.01
 African–American10 (0.89)25 (1.48)0.22
 Asian/Oceanian/Pacific Islander/Hawaiian52 (4.63)33 (1.95)<0.01
 Latin American/Hispanic38 (3.38)34 (2.01)0.03
 Mixed35 (3.11)33 (1.95)0.06
 Unknown383 (34.08)556 (32.86)0.52
Antibiotics in the preceding year, n (%)349 (31.05)1283 (75.83)<0.01
 Penicillins160 (45.85)416 (32.42)<0.01
 Tetracyclines45 (12.89)184 (14.34)0.54
 Cephalosporins23 (6.59)110 (8.57)0.27
 Quinolones37 (10.60)211 (16.45)<0.01
 Lincomycins8 (2.29)59 (4.60)0.07
 Macrolides62 (17.77)211 (16.45)0.61
 Sulfonamides11 (3.15)67 (5.22)0.14
 Glycopeptides1 (0.29)19 (1.48)<0.01
 Aminoglycosides2 (0.57)6 (0.47)0.28
Family history of gut disorders, n (%)193 (17.17)760 (44.92)<0.01
 IBS61 (31.61)431 (56.71)<0.01
 Ulcerative colitis26 (13.47)58 (7.63)0.01
 Crohn’s disease29 (17.79)58 (7.63)<0.01
 Diverticulitis77 (39.90)213 (28.03)<0.01
  • Antibiotics in the preceding year and family history of gut disorders contain groups that are not mutually exclusive.

  • Bolded values in table denote aggregate counts.

  • IBS, irritable bowel syndrome.