Table 1 Summary statistics of demographic data and phenotypes for C. diff cases and controls selected using the C. diff phenotyping algorithm.
N | Case n = 1349 | Control n = 18,512 | Overall n = 19,861 | Case–control differences |
|---|---|---|---|---|
Site | ||||
Children’s Hospital of Philadelphia | 11% (149) | 1.4% (265) | 2.1% (414) | X2 = 8.64 (P = 3.29 × 10–3) |
Cincinnati Children’s Medical Hospital | 1.0% (14) | 0.0% (0) | 0.1% (14) | X2 = 564.67 (P = 2.20 × 10–16) |
Columbia | 5.6% (76) | 0.5% (88) | 0.8% (164) | X2 = 408.56 (P = 2.20 × 10–16) |
Geisinger | 4.2% (57) | 4.9% (899) | 4.8% (956) | X2 = 1.09 (P = 0.30) |
Kaiser Permanente/UW | 4.2% (57) | 11% (2128) | 11% (2185) | X2 = 67.87 (P = 2.20 × 10–16) |
Mass General Brigham | 3.5% (47) | 8.8% (1623) | 8.4% (1670) | X2 = 45.571 (P = 1.47 × 10–11) |
Mayo Clinic | 7.2% (97) | 17% (3127) | 16% (3224) | X2 = 87.03 (P = 2.20 × 10–16) |
Marshfield | 2.4% (32) | 4.7% (861) | 4.5% (893) | X2 = 15.207 (P = 9.63 × 10–5) |
Mt. Sinai | 7.9% (106) | 15% (2776) | 15% (2882) | X2 = 51.64 (P = 3.29 × 10–3) |
Northwestern | 5.6% (76) | 2.0% (362) | 2.2% (438) | X2 = 78.88 (P = 2.20 × 10–16) |
Vanderbilt | 47% (638) | 34% (6383) | 35% (7021) | X2 = 90.34 (P = 2.20 × 10–16) |
Sex (female) | 51% (690) | 55% (10,232) | 55% (10,922) | X2 = 90.34 (P = 2.20 × 10–16) |
Median BMI (kg/m2)* | 20.8, 25.2, 29.8 | 24.4, 28.1, 32.9 | 24.2, 28.0, 32.8 | Z = 14.581 (P = 2.20 × 10–16) |
Median age* | 39.7, 57.3, 70.0 | 51.1, 64.9, 76.1 | 50.4, 64.4, 76.0 | Z = 14.372 (P = 2.20 × 10–16) |
Self-identified ancestry | ||||
American Indian or Alaska Native | 0.2% (3) | 0.2% (40) | 0.2% (43) | X2 = 0.002 (P = 0.96) |
Black or African American | 15% (196) | 19% (3562) | 19% (3758) | X2 = 21.75 (P = 3.10 × 10–6) |
Asian | 0.8% (11) | 0.8% (142) | 0.8% (153) | X2 = 0.04 (P = 0.84) |
Native Hawaiian or other Pacific Islander | 0.07% (1) | 0.02% (2) | 0.02% (3) | X2 = 0.46 (P = 0.50) |
White | 75% (1008) | 74% (13,716) | 74% (14,724) | X2 = 0.26 (P = 0.61) |
Unknown | 9.2% (124) | 5.0% (933) | 5.3% (1057) | X2 = 43.02 (P = 5.42 × 10–11) |
Not reported | 0.4% (6) | 0.6% (117) | 0.6% (123) | X2 = 0.72 (P = 0.40) |
Self-identified ethnicity | ||||
Hispanic or Latino | 6.0% (81) | 4.8% (895) | 4.9% (976) | X2 = 3.68 (P = 0.06) |
Not Hispanic or Latino | 88% (1193) | 92% (17,120) | 92% (18,313) | X2 = 28.62 (P = 8.80 × 10–8) |
Unknown | 5.6% (75) | 2.7% (497) | 2.9% (572) | X2 = 37.16 (P = 1.09 × 10–9) |
Genetically determined ancestry | ||||
African | 17% (235) | 21% (3849) | 21% (4084) | X2 = 8.75 (P = 3.10 × 10–3) |
Asian | 2.4% (32) | 1.6% (287) | 1.6% (319) | X2 = 5.37 (P = 2.05 × 10–2) |
European | 80% (1082) | 78% (14,376) | 78% (15,458) | X2 = 4.74 (P = 2.95 × 10–2) |
Antibiotic exposure (Within 7–62 days prior to index date) | ||||
High risk | 28% (376) | 21% (3832) | 21% (4208) | X2 = 38.74 (P = 4.85 × 10–10) |
Moderate risk | 11% (147) | 26% (4838) | 25% (4985) | X2 = 155.29 (P = 2.20 × 10–16) |
Low risk | 1.9% (25) | 1.5% (284) | 1.6% (309) | X2 = 0.84 (P = 0.36) |
No exposure | 59% (801) | 52% (9558) | 52% (10,359) | X2 = 30.233 (P = 3.83 × 10–8) |
Cancer (First record to index date + 7 days) | 20% (272) | 14% (2520) | 14% (2792) | X2 = 44.654 (P = 2.35 × 10–11) |
Chemotherapy (before 180 days prior to index date, after 7 days following index date) | 20% (270) | 12% (2263) | 13% (2533) | X2 = 68.60 (P = 2.20 × 10–16) |
Diabetes mellitus (Ever) | 24% (326) | 25% (4700) | 25% (5026) | X2 = 0.99 (P = 0.32) |
HIV (Ever) | 3.0% (44) | 2.0% (302) | 2.0% (346) | X2 = 19.52 (P = 9.94 × 10–6) |
Nursing home status (within 90 days prior to index date) | 11% (147) | 2.0% (393) | 3.0% (540) | X2 = 365.97 (P = 2.20 × 10–16) |
Corticosteroid medications (within 21 days prior to index date) | 17% (227) | 10% (1848) | 10% (2075) | X2 = 62.96 (P = 2.11 × 10–15) |
Transplant medications (first record to index date + 7 days) | 19% (250) | 6.0% (1059) | 7.0% (1309) | X2 = 335.23 (P = 2.20 × 10–16) |
