Table 3. Risk estimates for lung cancer associated with BMI in stratified analysis.
| Studies groups | No. of studies | BMI (kg/m2)† |
P‡ | I2 (95%CI) | ||||
|---|---|---|---|---|---|---|---|---|
| 22.5 | 25.0 | 27.5 | 30 | 35 | ||||
| All studies | 26 | 1.00(0.99–1.00) | 0.98(0.95–1.01) | 0.95(0.90–1.00) | 0.91(0.85–0.98) | 0.81(0.72–0.91) | 0.000 | 5(0–28) |
| Sex | ||||||||
| Male | 15 | 1.00(1.00–1.00) | 0.98(0.98–0.99) | 0.96(0.95–0.96) | 0.92(0.91–0.93) | 0.83(0.80–0.86) | 0.000 | 14(0–42) |
| Female | 9 | 1.00(1.00–1.00) | 0.98(0.98–0.99) | 0.97(0.96–0.97) | 0.94(0.93–0.96) | 0.88(0.84–0.93) | 0.042 | 28(0–56) |
| Smoking status | ||||||||
| Current smokers | 11 | 0.99(0.99–0.99) | 0.97(0.97–0.97) | 0.95(0.94–0.95) | 0.92(0.91–0.94) | 0.87(0.83–0.91) | 0.468 | 35(0–65) |
| Male | 5 | 0.99(0.99–0.99) | 0.97(0.97–0.98) | 0.95(0.95–0.96) | 0.93(0.92–0.95) | 0.88(0.82–0.96) | 0.921 | 0(0–60) |
| Female | 6 | 1.00(1.00–1.00) | 0.98(0.98–0.99) | 0.96(0.95–0.97) | 0.92(0.89–0.94) | 0.81(0.75–0.87) | 0.000 | 0(0–46) |
| Ex-smokers | 8 | 1.00(0.99–1.00) | 0.98(0.98–0.99) | 0.97(0.96–0.98) | 0.95(0.93–0.97) | 0.89(0.84–0.94) | 0.076 | 38(6–59) |
| Male | 5 | 1.00(1.00–1.00) | 0.99(0.98–1.00) | 0.97(0.96–0.99) | 0.95(0.92–0.98) | 0.89(0.82–0.97) | 0.198 | 40(0–68) |
| Female | 5 | 1.00(0.99–1.00) | 0.98(0.97–1.00) | 0.97(0.95–0.98) | 0.94(0.91–0.97) | 0.88(0.81–0.96) | 0.230 | 43(1–67) |
| Non-smokers | 12 | 1.00(1.00–1.00) | 0.98(0.97–0.99) | 0.97(0.94–0.99) | 0.96(0.91–1.01) | 0.94(0.81–1.08) | 0.815 | 27(0–50) |
| Male | 7 | 1.00(1.00–1.00) | 0.98(0.97–1.00) | 0.97(0.93–1.01) | 0.96(0.86–1.07) | 0.95(0.71–1.27) | 0.830 | 37(0–66) |
| Female | 6 | 1.00(1.00–1.00) | 0.98(0.96–1.01) | 0.97(0.94–1.00) | 0.95(0.89–1.02) | 0.92(0.76–1.10) | 0.850 | 23(0–56) |
| Histologic type | ||||||||
| Adenocarcinoma | 5 | 1.00(1.00–1.00) | 0.99(0.98–0.99) | 0.96(0.95–0.98) | 0.92(0.90–0.95) | 0.82(0.76–89) | 0.001 | 10(0–46) |
| Small cell carcinoma | 3 | 1.00(1.00–1.00) | 0.99(0.98–1.01) | 0.99(0.97–1.01) | 0.99(0.97–1.02) | 1.00(0.92–1.08) | 0.774 | 0(0–57) |
| Squamous cell carcinoma | 4 | 1.00(0.99–1.00) | 0.98(0.97–0.99) | 0.97(0.95–0.99) | 0.96(0.90–0.99) | 0.90(0.80–1.01) | 0.629 | 27(0–60) |
Note:
†The association between BMI and lung cancer risk was evaluated by relative risk (RR) and 95% confidence interval (CI). Besides, normal weight (BMI = 18.5–24.9 kg/m2) was regarded as a reference category.
‡P value for non-linearity.