Antibiotic use in the past four years and risk of colorectal adenoma, Nurses’ Health Study 2008–2010
| Antibiotic use in the past four years | |||||
|---|---|---|---|---|---|
| None | 1–14 days | 15 days to 2 months | 2 months+ | ptrend | |
| Total adenoma | |||||
| No. of cases (n=180) | 45 | 68 | 51 | 16 | |
| Age-adjusted* OR (95% CI) | 1 (referent) | 0.84 (0.57–1.23) | 0.98 (0.65–1.47) | 1.06 (0.59–1.91) | 0.54 |
| Multivariable† OR (95% CI) | 1 (referent) | 0.84 (0.56–1.26) | 1.02 (0.66–1.56) | 1.10 (0.60–2.02) | 0.44 |
| High risk‡ | |||||
| No. of cases (n=67) | 16 | 29 | 14 | 8 | |
| Age-adjusted* OR (95% CI) | 1 (referent) | 1.00 (0.54–1.86) | 0.74 (0.36–1.52) | 1.43 (0.60–3.40) | 0.76 |
| Multivariable† OR (95% CI) | 1 (referent) | 0.96 (0.52–1.80) | 0.72 (0.36–1.47) | 1.59 (0.66–3.81) | 0.62 |
| Low risk | |||||
| No. of cases (n=94) | 26 | 29 | 31 | 8 | |
| Age-adjusted* OR (95% CI) | 1 (referent) | 0.62 (0.36–1.06) | 1.04 (0.61–1.78) | 0.95 (0.43–2.13) | 0.35 |
| Multivariable† OR (95% CI) | 1 (referent) | 0.63 (0.36–1.11) | 1.14 (0.64–2.01) | 0.99 (0.42–2.31) | 0.27 |
| Proximal | |||||
| No. of cases (n=107) | 21 | 42 | 36 | 8 | |
| Age-adjusted* OR (95% CI) | 1 (referent) | 1.12 (0.66–1.91) | 1.53 (0.89–2.63) | 1.17 (0.51–2.68) | 0.29 |
| Multivariable† OR (95% CI) | 1 (referent) | 1.11 (0.64–1.92) | 1.64 (0.93–2.87) | 1.25 (0.54–2.89) | 0.18 |
| Distal | |||||
| No. of cases (n=77) | 25 | 27 | 20 | 5 | |
| Age-adjusted* OR (95% CI) | 1 (referent) | 0.60 (0.35–1.04) | 0.69 (0.38–1.26) | 0.59 (0.22–1.56) | 0.47 |
| Multivariable† OR (95% CI) | 1 (referent) | 0.60 (0.34–1.06) | 0.69 (0.37–1.31) | 0.63 (0.22–1.77) | 0.59 |
| Rectal | |||||
| No. of cases (n=25) | 5 | 12 | 5 | 3 | |
| Age-adjusted* OR (95% CI) | 1 (referent) | 1.32 (0.46–3.82) | 0.81 (0.23–2.85) | 1.61 (0.38–6.74) | 0.93 |
| Multivariable† OR (95% CI) | 1 (referent) | 1.43 (0.50–4.10) | 0.86 (0.25–2.91) | 1.77 (0.43–7.39) | 0.87 |
*Adjusted for age, time period of colonoscopy, number of reported endoscopies, time since most recent endoscopy and reason for current colonoscopy.
†Additionally adjusted for family history of colorectal cancer, history of diabetes, menopausal status and postmenopausal hormone use, body mass index, height, regular use of aspirin, current use of multivitamin, alcohol intake, smoking, total calorie, folate, calcium intake, red and processed meat intake and Alternate Healthy Eating Index 2010.
‡High-risk adenomas include adenoma ≥1 cm, or with tubulovillous/villous histology, or ≥3 adenomas.