Table 2.
Association Between Quintiles of the Cumulative Average of Fiber Intake and Newly Diagnosed Chronic Obstructive Pulmonary Disease in Women and Men, Nurses’ Health Study (1984–2000) and Health Professionals Follow-up Study (1986–1998) (n = 111,580)
| Quintile of Intake |
Ptrend | |||||
| Quintile 1 | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | ||
| Total fiber | ||||||
| Median, g/day | 11.2 | 15.0 | 18.2 | 22.0 | 28.4 | |
| No. of cases | 234 | 182 | 153 | 156 | 107 | |
| No. of person-years | 154,421 | 157,000 | 158,251 | 157,270 | 155,614 | |
| Multivariate RR (95% CI)a | 1.00 | 0.72 (0.59, 0.87) | 0.57 (0.47, 0.70) | 0.56 (0.46, 0.68) | 0.36 (0.29, 0.45) | <0.001 |
| Multivariate RR (95% CI)b | 1.00 | 0.80 (0.65, 0.98) | 0.70 (0.56, 0.88) | 0.75 (0.59, 0.95) | 0.55 (0.42, 0.74) | <0.001 |
| Multivariate RR (95% CI)c | 1.00 | 0.80 (0.65, 0.99) | 0.72 (0.57, 0.90) | 0.79 (0.62, 1.01) | 0.60 (0.45, 0.80) | 0.002 |
| Multivariate RR (95% CI)d | 1.00 | 0.82 (0.67, 1.01) | 0.76 (0.60, 0.95) | 0.85 (0.66, 1.09) | 0.67 (0.50, 0.90) | 0.03 |
| Cereal fiber | ||||||
| Median, g/day | 2.2 | 3.5 | 4.7 | 6.2 | 9.0 | |
| No. of cases | 230 | 195 | 150 | 145 | 112 | |
| No. of person-years | 153,150 | 156,321 | 157,597 | 157,597 | 157,984 | |
| Multivariate RR (95% CI)a | 1.00 | 0.84 (0.69, 1.01) | 0.63 (0.51, 0.77) | 0.59 (0.48, 0.72) | 0.42 (0.33, 0.52) | <0.001 |
| Multivariate RR (95% CI)b | 1.00 | 0.99 (0.81, 1.20) | 0.84 (0.68, 1.05) | 0.86 (0.69, 1.09) | 0.71 (0.55, 0.92) | 0.007 |
| Multivariate RR (95% CI)c | 1.00 | 0.99 (0.81, 1.21) | 0.85 (0.68, 1.06) | 0.87 (0.69, 1.09) | 0.72 (0.56, 0.93) | 0.008 |
| Multivariate RR (95% CI)d | 1.00 | 0.99 (0.82, 1.21) | 0.86 (0.69, 1.08) | 0.90 (0.72, 1.14) | 0.77 (0.59, 0.99) | 0.04 |
| Fruit fiber | ||||||
| Median, g/day | 1.4 | 2.6 | 3.7 | 5.1 | 7.6 | |
| No. of cases | 264 | 170 | 152 | 147 | 99 | |
| No. of person-years | 154,559 | 157,843 | 158,025 | 157,378 | 154,751 | |
| Multivariate RR (95% CI)a | 1.00 | 0.55 (0.45, 0.67) | 0.45 (0.37, 0.55) | 0.40 (0.33, 0.49) | 0.25 (0.20, 0.31) | <0.001 |
| Multivariate RR (95% CI)b | 1.00 | 0.82 (0.67, 0.99) | 0.82 (0.67, 1.01) | 0.88 (0.71, 1.08) | 0.63 (0.49, 0.81) | 0.003 |
| Multivariate RR (95% CI)c | 1.00 | 0.83 (0.68, 1.01) | 0.86 (0.70, 1.05) | 0.93 (0.75, 1.16) | 0.68 (0.52, 0.87) | 0.02 |
| Multivariate RR (95% CI)d | 1.00 | 0.86 (0.70, 1.05) | 0.91 (0.74, 1.13) | 1.02 (0.82, 1.28) | 0.77 (0.59, 1.01) | 0.31 |
| Vegetable fiber | ||||||
| Median, g/day | 3.5 | 5.0 | 6.2 | 7.8 | 10.7 | |
| No. of cases | 206 | 154 | 176 | 157 | 139 | |
| No. of person-years | 154,603 | 157,742 | 158,033 | 157,186 | 154,992 | |
| Multivariate RR (95% CI)a | 1.00 | 0.71 (0.58, 0.88) | 0.79 (0.65, 0.97) | 0.70 (0.57, 0.86) | 0.60 (0.49, 0.75) | <0.001 |
| Multivariate RR (95% CI)b | 1.00 | 0.76 (0.61, 0.94) | 0.88 (0.71, 1.08) | 0.81 (0.65, 1.01) | 0.74 (0.58, 0.93) | 0.04 |
| Multivariate RR (95% CI)c | 1.00 | 0.77 (0.62, 0.95) | 0.89 (0.73, 1.10) | 0.85 (0.68, 1.06) | 0.81 (0.64, 1.03) | 0.22 |
| Multivariate RR (95% CI)d | 1.00 | 0.79 (0.63, 0.97) | 0.94 (0.76, 1.16) | 0.92 (0.73, 1.15) | 0.92 (0.71, 1.18) | 0.89 |
Abbreviations: CI, confidence interval; RR, relative risk.
Adjusted for age and sex.
Adjusted for age, sex, smoking status, pack-years, pack-years2, and energy intake.
Adjusted for age, sex, smoking status, pack-years, pack-years2, energy intake, US region, physician visits, body mass index, and physical activity.
Adjusted for age, sex, smoking status, pack-years, pack-years, energy intake, US region, physician visits, body mass index, physical activity, diabetes, omega-3 polyunsaturated fatty acid intake (from foods and supplements), cured meat intake, and other sources of fiber (total fiber intake not adjusted for the specific fiber types).