Table 2: Subgroup analyses of excess weight (BMI≥25 kg/m2) and the risk of lung cancer.

From: Body mass index and risk of lung cancer: Systematic review and dose-response meta-analysis

Studies groupsOverweight (25≤BMI≤29.9 kg/m2)Obesity (BMI≥30 kg/m2)
NRR (95% CI)HeterogeneityE-TNRR (95% CI)HeterogeneityE–T
I2PI2P
All studies290.82(0.77–0.86)35.70.020.51290.78(0.74–0.83)40.30.010.457
Sex
 Male160.78(0.72–0.85)41.30.040.27160.77(0.70–0.84)40.10.050.20
 Female130.88(0.79–0.9835)35.30.100.55130.78(0.71–0.86)32.20.1250.35
Geographic location
 Europe100.82(0.76–0.89)0.00.920.79100.80(0.75–0.86)0.00.710.48
 North America110.84(0.78–0.91)22.10.210.52110.79(0.74–0.84)16.90.270.40
 Asia80.79 (0.67–0.93)71.20.000.5480.74(0.59–0.93)650.000.39
Body size assessment
 Measured210.84(0.79–0.89)32.80.050.56210.79(0.74–0.84)19.90.180.39
 Self-reported80.73(0.62–0.86)42.50.120.4080.71(0.58–0.88)64.70.010.29
Smoking status
 Current smokers90.79(0.71–0.87)49.90.030.0690.72(0.66–0.78)6.40.380.05
 Ex-smokers100.91(0.85–0.98)51.00.020.07100.77(0.69–0.85)22.90.220.07
 Non-smokers140.86 (0.78–0.94)40.60.040.99120.86(0.75–0.98)22.80.210.13
Histologic type
 Adenocarcinoma40.92 (0.85–0.99)35.80.170.3140.79(0.71–0.88)0.00.740.25
 Small cell carcinoma31.04(0.91–1.18)29.90.230.9630.84(0.56–1.26)63.00.030.57
 Squamous cell carcinoma40.88(0.79–0.98)34.90.190.0740.76(0.63–0.92)0.00.830.05
Number of cases
 <20050.75(0.58–0.96)36.70.150.0850.79(0.58–1.08)22.60.250.69
 200–50070.71(0.61–0.81)33.80.170.5270.66(0.58–0.75)0.00.720.32
 500–100080.89(0.81–0.97)24.30.230.0780.67(0.58–0.77)0.00.830.80
 ≥100090.85(0.80–0.90)0.00.480.4790.83(0.78–0.88)36.10.100.62
Duration of follow-up
 <10 years120.76(0.68–0.85)52.70.020.40120.68(0.60–0.78)28.30.170.75
 ≥10 years170.85(0.80–0.91)18.80.200.50170.81(0.76–0.85)20.40.190.49
Study quality score
 6 sars31.10(0.88–1.39)0.00.450.9530.65(0.46–0.91)0.00.790.92
 7 stars80.67(0.59–0.79)39.20.110.6680.66(0.55–0.78)23.30.230.07
 8 stars120.82(0.77–0.88)0.00.620.81120.86(0.80–0.92)0.00.470.82
 9 stars60.88(0.82–0.94)0.00.730.3160.77(0.73–0.82)31.90.170.81
Adjustment for age, smoking and education
 Yes90.82(0.76–0.88)2.70.420.5190.80(0.75–0.85)14.70.310.10
 No200.82(0.78–0.87)45.80.010.86200.76(0.69–0.84)39.90.020.70
Adjustment for age, smoking and physical activity
 Yes100.82(0.74–0.91)58.30.000.83100.79(75–0.84)28.60.160.13
 No190.82(0.77–0.88)15.40.260.89190.77(0.69–0.85)34.70.050.69
Adjustment for age, smoking and alcohol consumption
 Yes120.80(0.71–0.89)54.40.010.74120.80(0.74–0.86)29.50.150.05
 No170.84(0.78–0.89)23.50.150.76170.76(0.70–0.83)31.20.080.97
  1. Note: All the groups were compared with normal weight (18.5 ≤ BMI ≤ 24.9 kg/m2) as the reference category. N: Number of the studies; E–T: Egger’s test.