Table 1.
Selected characteristics of 1097 participants in the American Gut Project and associations with history of cesarean birth or appendectomy.
| Cesarean birth history (N = 92) |
Appendectomy history (N = 115) |
|||||||
|---|---|---|---|---|---|---|---|---|
| Variable (N; Na) | Estimate | Std. error | z value | P-value⁎ | Estimate | Std. error | z value | P-value⁎ |
| Age, mean 46 years (SE 16 years) | − 0.04 | 0.01 | − 6.11 | 9.7E− 10 | 0.05 | 0.01 | 6.51 | 7.5E− 11 |
| Body mass index, mean 24 (SE 5) kg/m2 | 0.01 | 0.02 | 0.23 | 0.81 | 0.08 | 0.02 | 4.26 | 2.1E− 05 |
| Sex, male (461; 486) | 0.01 | 0.22 | 0.05 | 0.96 | − 0.28 | 0.20 | − 1.37 | 0.17 |
| Gluten, yes (200; 204) | − 0.05 | 0.28 | − 0.19 | 0.85 | − 0.22 | 0.27 | − 0.80 | 0.42 |
| Lactose, yes (183; 187) | − 0.13 | 0.29 | − 0.43 | 0.67 | − 0.20 | 0.28 | − 0.74 | 0.46 |
| Asthma, yes (86; 89) | 0.07 | 0.39 | 0.19 | 0.85 | 0.08 | 0.35 | 0.22 | 0.83 |
| Race/ethnicity | ||||||||
| Caucasian, non-Hispanic (964; 995) | Referent | Referent | ||||||
| African American (10; 10) | − 13.23 | 460.24 | − 0.03 | 0.98 | − 13.49 | 460.24 | − 0.03 | 0.98 |
| Hispanic (16; 16) | − 0.37 | 1.04 | − 0.36 | 0.72 | 0.13 | 0.76 | 0.17 | 0.87 |
| Asian or Pacific Islander (34; 38) | 0.58 | 0.50 | 1.16 | 0.24 | − 1.54 | 1.02 | − 1.51 | 0.13 |
| Other (16; 17) | − 0.37 | 1.04 | − 0.36 | 0.72 | − 0.70 | 1.04 | − 0.67 | 0.50 |
| Geographic region | ||||||||
| California (206; 213) | Referent | Referent | ||||||
| Other western U.S. (224; 235) | 0.04 | 0.36 | 0.10 | 0.92 | − 0.64 | 0.30 | − 2.12 | 0.03 |
| Midwestern U.S. (164; 169) | − 0.06 | 0.40 | − 0.16 | 0.87 | − 0.60 | 0.33 | − 1.80 | 0.07 |
| Northeastern U.S. (196; 200) | 0.35 | 0.35 | 1.02 | 0.31 | − 0.36 | 0.30 | − 1.21 | 0.23 |
| Southern U.S. (210; 218) | 0.33 | 0.34 | 0.96 | 0.34 | − 0.56 | 0.30 | − 1.85 | 0.06 |
| Canada (22; 23) | 0.63 | 0.67 | 0.93 | 0.35 | − 0.16 | 0.65 | − 0.25 | 0.80 |
| Europe (11; 11) | − 14.09 | 723.49 | − 0.02 | 0.98 | − 0.57 | 1.07 | − 0.53 | 0.59 |
| Australia (6; 5) | − 14.09 | 979.61 | − 0.01 | 0.99 | 1.33 | 0.93 | 1.42 | 0.15 |
| Antibiotic use | ||||||||
| None in past year (793; 828) | Referent | Referent | ||||||
| Yes, 2–6 months ago (112; 114) | − 0.25 | 0.39 | − 0.63 | 0.53 | 0.48 | 0.29 | 1.67 | 0.10 |
| Yes, 7–12 months ago (135; 134) | 0.08 | 0.32 | 0.25 | 0.80 | 0.29 | 0.28 | 1.03 | 0.30 |
| Weight change | ||||||||
| Remained stable (877; 908) | Referent | Referent | ||||||
| Decreased > 10 lb (104; 107) | 0.67 | 0.40 | 1.67 | 0.10 | − 0.43 | 0.38 | − 1.11 | 0.27 |
| Increased > 10 lb (53; 54) | 0.41 | 0.50 | 0.82 | 0.41 | − 0.19 | 0.48 | − 0.40 | 0.69 |
| Diet type | ||||||||
| Omnivore (828; 856) | Referent | Referent | ||||||
| No red meat (64; 68) | 0.25 | 0.42 | 0.61 | 0.54 | 0.15 | 0.39 | 0.39 | 0.70 |
| Vegan (29; 29) | 0.19 | 0.62 | 0.31 | 0.76 | 0.01 | 0.62 | 0.01 | 0.99 |
| Vegetarian (44; 47) | − 0.26 | 0.61 | − 0.43 | 0.67 | − 0.21 | 0.53 | − 0.39 | 0.70 |
| Pescetarian (71; 72) | 0.14 | 0.42 | 0.33 | 0.74 | 0.56 | 0.34 | 1.66 | 0.10 |
| Alcohol consumption | ||||||||
| Never (221; 226) | Referent | Referent | ||||||
| Rarely (few times/month, 255; 265) | 0.05 | 0.32 | 0.16 | 0.87 | 0.22 | 0.30 | 0.73 | 0.46 |
| Occasionally (1–2 times/week, 214; 219) | 0.20 | 0.33 | 0.60 | 0.55 | − 0.13 | 0.34 | − 0.40 | 0.69 |
| Regularly (3–5 times/week, 205; 213) | 0.08 | 0.34 | 0.24 | 0.81 | 0.55 | 0.30 | 1.83 | 0.07 |
| Daily (142; 149) | − 0.33 | 0.42 | − 0.78 | 0.43 | 0.01 | 0.36 | 0.03 | 0.97 |
| Tobacco smoking | ||||||||
| Never (991; 1028) | Referent | Referent | ||||||
| Rarely (few times/month, 25; 25) | 1.01 | 0.51 | 1.96 | 0.05 | − 0.32 | 0.74 | − 0.43 | 0.67 |
| More than rarely (17; 16) | 0.85 | 0.65 | 1.32 | 0.19 | − 0.59 | 1.04 | − 0.57 | 0.57 |
a
Number of participants, cesarean birth analysis; appendectomy analysis.
⁎
P-values by Wald test.