From: Body mass index and lung cancer risk in never smokers: a meta-analysis
Categories | Subgroups | Number of studies | RR (95% CI) | P value | Heterogeneity | P-interaction | ||
---|---|---|---|---|---|---|---|---|
chi-squared | I 2 | P-heterogeneity | ||||||
Obesity | 18 | 0.78(0.65–0.94) | 0.01 | 37.23 | 54.30% | < 0.01 | ||
Design | Cohort | 14 | 0.74(0.60–0.91) | < 0.01 | 27.83 | 53.30% | 0.01 | 0.32 |
Case-control | 4 | 0.97(0.58–1.62) | 0.90 | 8.75 | 65.70% | 0.03 | ||
Outcome | Incidence | 15 | 0.79(0.63–0.99) | 0.04 | 30.83 | 54.60% | < 0.01 | 0.74 |
Mortality | 3 | 0.71(0.45–1.12) | 0.14 | 6.40 | 68.70% | 0.04 | ||
Gender | Male | 5 | 0.69(0.41–1.15) | 0.16 | 16.58 | 69.80% | < 0.01 | 0.81 |
Female | 8 | 0.86(0.72–1.02) | 0.08 | 7.49 | 19.90% | 0.28 | ||
Ethnicity | Non-Asian | 13 | 0.82(0.64–1.04) | 0.10 | 27.92 | 57.00% | < 0.01 | 0.51 |
Asian | 5 | 0.70(0.54–0.91) | < 0.01 | 5.56 | 28.00% | 0.24 | ||
Quality | High | 12 | 0.76(0.61–0.94) | 0.01 | 27.5 | 60.00% | 0.004 | 0.72 |
Low | 6 | 0.84(0.55–1.29) | 0.43 | 9.72 | 48.60% | 0.08 | ||
Diagnosis | Registry | 10 | 0.77(0.59–1.00) | 0.05 | 22.28 | 59.60% | < 0.01 | 0.89 |
Pathology | 8 | 0.79(0.59–1.06) | 0.11 | 14.16 | 50.60% | 0.05 | ||
Adjustment for confounders | ||||||||
Alcohol intake | Yes | 11 | 0.83(0.68–1.02) | 0.07 | 18.98 | 47.30% | 0.04 | 0.49 |
No | 7 | 0.68(0.45–1.04) | 0.07 | 16.25 | 63.10% | 0.01 | ||
Vegetable/fruit intake | Yes | 6 | 0.81(0.58–1.13) | 0.22 | 12.80 | 60.90% | 0.02 | 0.80 |
No | 12 | 0.76(0.59–0.97) | 0.03 | 23.41 | 53.00% | 0.02 | ||
Physical activity | Yes | 9 | 0.91(0.75–1.11) | 0.34 | 12.18 | 34.30% | 0.14 | 0.19 |
No | 9 | 0.67(0.49–0.93) | 0.02 | 18.15 | 55.90% | 0.02 | ||
Medical historya | Yes | 3 | 0.78(0.58–0.95) | 0.24 | 35.80 | 60.90% | < 0.01 | 0.61 |
No | 15 | 0.90(0.76–1.07) | 0.02 | 0.78 | 0.00% | 0.68 | ||
Overweight | 15 | 0.76(0.65–0.87) | < 0.01 | 28.37 | 50.60% | 0.01 | ||
Design | Cohort | 12 | 0.74(0.62–0.88) | < 0.01 | 27.30 | 59.70% | < 0.01 | 0.78 |
Case-control | 3 | 0.80(0.63–1.02) | 0.08 | 1.03 | 0.00% | 0.60 | ||
Outcome | Incidence | 12 | 0.76(0.64–0.90) | < 0.01 | 16.92 | 35.00% | 0.11 | 0.93 |
Mortality | 3 | 0.73(0.53–1.01) | 0.06 | 10.51 | 81.00% | < 0.01 | ||
Gender | Male | 5 | 0.92(0.62–1.36) | 0.68 | 14.38 | 72.20% | < 0.01 | 0.44 |
Female | 8 | 0.82(0.72–0.93) | < 0.01 | 6.52 | 0.00% | 0.48 | ||
Ethnicity | Non-Asian | 11 | 0.87(0.78–0.97) | < 0.01 | 10.34 | 3.30% | 0.41 | 0.09 |
Asian | 4 | 0.61(0.44–0.86) | < 0.01 | 10.87 | 72.40% | 0.01 | ||
Quality | High | 10 | 0.85(0.77–0.94) | < 0.01 | 9.47 | 4.90% | 0.40 | 0.32 |
Low | 5 | 0.70(0.46–1.06) | 0.09 | 13.76 | 70.90% | < 0.01 | ||
Diagnosis | Registry | 8 | 0.82(0.68–0.98) | 0.03 | 14.38 | 51.30% | 0.04 | 0.25 |
Pathology | 7 | 0.68(0.55–0.84) | < 0.01 | 8.74 | 31.40% | 0.19 | ||
Adjustment for confounders | ||||||||
Alcohol intake | Yes | 11 | 0.79(0.68–0.92) | < 0.01 | 18.32 | 45.40% | 0.05 | 0.37 |
No | 4 | 0.67(0.46–0.97) | 0.03 | 6.36 | 52.80% | 0.10 | ||
Vegetable/fruit intake | Yes | 5 | 0.89(0.79–0.99) | 0.03 | 1.46 | 0.00% | 0.83 | 0.15 |
No | 10 | 0.68(0.54–0.85) | < 0.01 | 22.26 | 50.60% | < 0.01 | ||
Physical activity | Yes | 9 | 0.87(0.77–0.97) | 0.02 | 8.86 | 9.70% | 0.35 | 0.14 |
No | 6 | 0.66(0.49–0.88) | < 0.01 | 12.85 | 61.10% | 0.02 | ||
Medical historya | Yes | 3 | 0.89(0.79–1.00) | 0.05 | 24.35 | 0.00% | 0.66 | 0.42 |
No | 12 | 0.72(0.60–0.87) | < 0.01 | 0.84 | 50.60% | 0.01 | ||
Excess weight | 23 | 0.77(0.68–0.88) | < 0.01 | 58.46 | 62.40% | < 0.01 | ||
Design | Cohort | 16 | 0.80(0.69–0.94) | < 0.01 | 40.07 | 62.60% | < 0.01 | 0.47 |
Case-control | 7 | 0.71(0.56–0.91) | < 0.01 | 13.78 | 56.50% | 0.03 | ||
Outcome | Incidence | 19 | 0.75(0.64–0.88) | < 0.01 | 38.12 | 52.80% | < 0.01 | 0.60 |
Mortality | 4 | 0.83(0.63–1.10) | 0.19 | 16.73 | 82.10% | < 0.01 | ||
Gender | Male | 8 | 0.88(0.70–1.11) | 0.29 | 17.94 | 55.40% | 0.02 | 0.85 |
Female | 12 | 0.75(0.62–0.91) | < 0.01 | 28.89 | 61.90% | < 0.01 | ||
Ethnicity | Non-Asian | 14 | 0.80(0.68–0.95) | < 0.01 | 28.25 | 54.00% | < 0.01 | 0.66 |
Asian | 9 | 0.74(0.59–0.94) | 0.01 | 26.05 | 69.30% | < 0.01 | ||
Quality | High | 16 | 0.83(0.73–0.95) | < 0.01 | 30.06 | 50.10% | 0.01 | 0.18 |
Low | 7 | 0.68(0.50–0.90) | < 0.01 | 17.7 | 66.10% | < 0.01 | ||
Diagnosis | Registry | 11 | 0.88(0.75–1.05) | 0.15 | 24.27 | 58.80% | < 0.01 | 0.06 |
Pathology | 12 | 0.68(0.57–0.81) | < 0.01 | 19.97 | 44.90% | 0.05 | ||
Adjustment for confounders | ||||||||
Alcohol intake | Yes | 12 | 0.83(0.71–0.97) | 0.02 | 26.74 | 58.90% | 0.01 | 0.31 |
No | 11 | 0.71(0.57–0.89) | < 0.01 | 22.73 | 56.00% | < 0.01 | ||
Vegetable/fruit intake | Yes | 7 | 0.85(0.69–1.05) | 0.13 | 17.29 | 57.10% | < 0.01 | 0.37 |
No | 16 | 0.73(0.62–0.87) | < 0.01 | 34.93 | 65.30% | < 0.01 | ||
Physical activity | Yes | 9 | 0.87(0.77–0.99) | 0.04 | 10.14 | 21.10% | 0.26 | 0.52 |
No | 14 | 0.75(0.61–0.92) | < 0.01 | 41.15 | 68.40% | < 0.01 | ||
Medical historya | Yes | 7 | 0.84(0.68–1.04) | 0.11 | 13.32 | 55.00% | 0.04 | 0.52 |
No | 16 | 0.75(0.63–0.89) | < 0.01 | 40.57 | 63.00% | < 0.01 | ||
BMI increase per 5 Kg/m2 | 28 | 0.89(0.84–0.95) | < 0.01 | 86.44 | 68.80% | < 0.01 | ||
Design | Cohort | 20 | 0.89(0.82–0.96) | < 0.01 | 58.12 | 67.30% | < 0.01 | 0.88 |
Case-control | 8 | 0.90(0.79–1.03) | 0.13 | 24.77 | 71.70% | 0.01 | ||
Outcome | Incidence | 23 | 0.89(0.83–0.96) | < 0.01 | 65.3 | 66.30% | < 0.01 | 0.98 |
Mortality | 5 | 0.89(0.76–1.04) | 0.16 | 20.98 | 80.90% | < 0.01 | ||
Gender | Male | 12 | 0.96(0.83–1.11) | 0.60 | 28.43 | 61.30% | < 0.01 | 0.42 |
Female | 13 | 0.89(0.81–0.97) | < 0.01 | 34.74 | 65.50% | < 0.01 | ||
Ethnicity | Non-Asian | 18 | 0.91(0.84–0.98) | 0.01 | 47.23 | 64.00% | < 0.01 | 0.66 |
Asian | 10 | 0.88(0.78–0.98) | 0.03 | 33.12 | 72.80% | < 0.01 | ||
Quality | High | 20 | 0.91(0.86–0.98) | < 0.01 | 51.74 | 63.30% | < 0.01 | 0.39 |
Low | 8 | 0.85(0.72–1.00) | 0.05 | 26.41 | 73.50% | < 0.01 | ||
Diagnosis | Registry | 15 | 0.93(0.86–1.00) | 0.06 | 42.41 | 67.00% | < 0.01 | 0.35 |
Pathology | 13 | 0.86(0.78–0.95) | < 0.01 | 32.26 | 62.80% | < 0.01 | ||
Adjustment for confounders | ||||||||
Alcohol intake | Yes | 15 | 0.89(0.83–0.95) | < 0.01 | 36.97 | 62.10% | < 0.01 | 0.60 |
No | 13 | 0.92(0.79–1.07) | 0.28 | 48.42 | 75.20% | < 0.01 | ||
Vegetable/fruit intake | Yes | 7 | 0.93(0.84–1.02) | 0.13 | 12.57 | 52.3% | 0.05 | 0.77 |
No | 21 | 0.89(0.82–0.96) | < 0.01 | 72.90 | 72.6% | < 0.01 | ||
Physical activity | Yes | 10 | 0.92(0.86–0.98) | < 0.01 | 11.33 | 20.60% | 0.25 | 0.96 |
No | 18 | 0.90(0.81–0.99) | < 0.01 | 86.44 | 77.3% | < 0.01 | ||
Medical historya | Yes | 11 | 0.90(0.83–0.97) | < 0.01 | 29.05 | 65.60% | < 0.01 | 0.84 |
No | 17 | 0.88(0.80–0.98) | 0.02 | 56.45 | 71.70% | < 0.01 |