Table 4.
All-cause mortality among participants with Crohn’s disease or ulcerative colitis according to lifestyle factors
| Variables | Crohn’s disease | Ulcerative colitis | ||||
|---|---|---|---|---|---|---|
| Death/Person-year | Model 1 HR (95% CI)a | Model 2 HR (95% CI)b | Death/Person-year | Model 1 HR (95% CI)a | Model 2 HR (95% CI)b | |
| Smoking status | ||||||
| Never smoker | 26/2299 | (reference) | 1 (reference) | 28/3022 | 1 (reference) | 1 (reference) |
| Past smoker | 41/1935 | 1.54 (0.86–2.78) | 1.66 (0.87–3.16) | 46/2776 | 1.09 (0.63–1.88) | 1.06 (0.57–1.97) |
| Current smoker | 16/508 | 6.85 (3.07–15.30) | 6.32 (2.66–14.99) | 6/264 | 2.32 (0.86–6.24) | 2.75 (0.88–8.63) |
| Pack-years of smoking | ||||||
| Never smoker | 23/2119 | 1 (reference) | 1 (reference) | 24/2958 | 1 (reference) | 1 (reference) |
| ≤10 | 6/568 | 1.64 (0.60–4.49) | 1.72 (0.58–5.13) | 8/1130 | 0.82 (0.35–1.94) | 1.10 (0.44–2.75) |
| 10.1–25 | 20/1008 | 2.22 (1.08–4.59) | 2.07 (0.89–4.82) | 14/999 | 1.01 (0.45–2.26) | 0.75 (0.30–1.89) |
| >25 | 34/1047 | 2.26 (1.20–4.28) | 2.77 (1.38–5.56) | 34/975 | 1.89 (1.01–3.57) | 1.34 (0.65–2.76) |
| P for trendc | 0.0005 | 0.0005 | 0.004 | 0.13 | ||
| Body mass index | ||||||
| <18.5 kg/m2 | 2/102 | 0.65 (0.15–2.90) | 0.63 (0.12–3.23) | 3/69 | 6.75 (1.66–27.41) | 7.87 (1.32–46.85) |
| 18.5–24.9 kg/m2 | 38/2215 | 1 (reference) | 1 (reference) | 33/3099 | 1 (reference) | 1 (reference) |
| 25–29.9 kg/m2 | 25/1488 | 0.93 (0.51–1.69) | 1.04 (0.51–2.14) | 30/1815 | 1.48 (0.82–2.68) | 1.49 (0.75–2.97) |
| ≥30 kg/m2 | 18/936 | 1.31 (0.68–2.52) | 1.56 (0.76–3.21) | 14/1079 | 1.71 (0.77–3.79) | 1.56 (0.63–3.85) |
| P for trend <25 kg/m2c | 0.59 | 0.48 | 0.19 | 0.007 | ||
| P for trend ≥18.5 kg/m2c | 0.25 | 0.13 | 0.05 | 0.26 | ||
| Physical activity | ||||||
| Quintile 1 | 21/965 | 1 (reference) | 1 (reference) | 27/1179 | 1 (reference) | 1 (reference) |
| Quintile 2 | 16/961 | 0.85 (0.40–1.83) | 0.73 (0.30–1.76) | 18/1151 | 0.42 (0.21–0.83) | 0.41 (0.19–0.92) |
| Quintile 3 | 16/905 | 0.66 (0.32–1.38) | 0.65 (0.29–1.44) | 18/1381 | 0.28 (0.14–0.60) | 0.27 (0.12–0.64) |
| Quintile 4 | 14/1026 | 0.60 (0.27–1.29) | 0.74 (0.30–1.79) | 9/1154 | 0.19 (0.08–0.46) | 0.21 (0.08–0.56) |
| Quintile 5 | 16/884 | 1.13 (0.53–2.41) | 0.81 (0.34–1.89) | 8/1196 | 0.13 (0.04–0.39) | 0.14 (0.04–0.46) |
| P for trendd | 0.74 | 0.82 | 0.0001 | 0.002 | ||
| Alternate Mediterranean diet score | ||||||
| <4 | 48/2256 | 1 (reference) | 1 (reference) | 39/2520 | 1 (reference) | 1 (reference) |
| ≥4 | 35/2486 | 0.54 (0.33–0.89) | 0.50 (0.29–0.87) | 41/3528 | 0.69 (0.42–1.15) | 1.25 (0.68–2.28) |
| P | 0.01 | 0.01 | 0.16 | 0.47 | ||
| Alcohol consumption | ||||||
| Nondrinker | 42/2202 | 1 (reference) | 1 (reference) | 36/2549 | 1 (reference) | 1 (reference) |
| 0.1–5 g/d | 19/1429 | 0.85 (0.46–1.58) | 0.82 (0.43–1.56) | 19/1934 | 0.42 (0.22–0.83) | 0.53 (0.25–1.10) |
| 5.1–15 g/d | 10/716 | 0.92 (0.43–1.96) | 1.01 (0.44–2.30) | 16/1011 | 0.82 (0.42–1.58) | 1.17 (0.53–2.61) |
| >15 g/d | 12/395 | 2.26 (1.06–4.83) | 2.41 (1.04–5.62) | 9/567 | 0.62 (0.25–1.55) | 0.86 (0.31–2.42) |
| P for trend ≤5 g/dc | 0.33 | 0.26 | 0.13 | 0.49 | ||
| P for trend >0 g/dc | 0.01 | 0.005 | 0.19 | 0.08 | ||
Abbreviations: NHS, Nurses’ Health Study; HPFS, Health Professionals Follow-up Study; HR, hazard ratio; CI, confidence interval; BMI, body mass index; MET, metabolic equivalent of task; aMED, Alternate Mediterranean Diet Score.
Cox proportional hazards regression model stratified by age at diagnosis (in 5-year intervals), year of diagnosis (<1990, 1990–1999, 2000–2009, ≥2010), cohort (NHS, NHS II, HPFS), with additional adjustment for age at diagnosis (continuous, year).
Further adjusted for race (Southern European/Mediterranean, Scandinavian, other Caucasian, other races), post-diagnostic smoking status (never smoker, 0.1–10, 10.1–25, >25 pack-years), BMI (<18.5, 18.5–24.9, 25–29.9, ≥30 kg/m2), physical activity (in quintiles, MET-hr/wk), aMED (in quartiles), and alcohol consumption (nondrinker, 0.1–5, 5.1–15, >15 g/d).
P for trend was calculated by treating the exposure as a continuous variable.
P for trend was calculated using the median of each quintile as a continuous variable.