Skip to main content
. 2020 Dec 31;13(1):113. doi: 10.3390/cancers13010113

Table 3.

Adjusted risk of lung cancer according to the measures of various smoking statuses.

Smoking Measures Male Female Sex–Smoking Interaction
N Adjusted HR (95% CI) 1 p-Value N Adjusted HR (95% CI) 1 p-Value
Smoking status
  Never 1,157,106 1.00 (reference) - 4,010,591 1.00 (reference) - -
  Former 513,760 1.27 (1.23–1.33) <0.001 26,111 1.43 (1.16–1.81) <0.001 0.261
  Current 777,070 2.71 (2.63–2.79) <0.001 84,506 2.70 (2.48–2.94) <0.001 -
Duration of smoking
  1–9 years 53,677 1.00 (reference) - 25,164 1.00 (reference) - -
  10–19 years 186,724 0.95 (0.79–1.14) 0.558 34,884 1.40 (0.95–2.06) 0.093 -
  20–29 years 475,970 1.48 (1.26–1.75) <0.001 29,250 2.09 (1.45–3.01) <0.001 <0.001
  ≥30 years 574,023 3.07 (2.62–3.61) <0.001 21,269 3.16 (2.20–4.54) <0.001 -
Duration of former smoking
  1–9 years 41,386 1.00 (reference) - 9643 1.00 (reference) - -
  10–19 years 129,515 1.09 (0.85–1.38) 0.496 8331 2.39 (0.85–6.73) 0.099 -
  20–29 years 169,258 1.52 (1.22–1.90) <0.001 4849 5.49 (2.07–14.56) <0.001 0.017
  ≥30 years 173471 2.81 (2.27–3.49) <0.001 3265 5.92 (2.17–16.15) <0.001 -
Duration of current smoking
  1–9 years 12,291 1.00 (reference) - 15,521 1.00 (reference) - -
  10–19 years 57,209 0.81 (0.60–1.08) 0.151 26,553 1.14 (0.75–1.73) 0.538 -
  20–29 years 306,712 1.08 (0.85–1.39) 0.534 24,401 1.52 (1.02–2.25) 0.038 0.019
  ≥30 years 400,552 1.81 (1.42–2.31) <0.001 18,004 2.36 (1.60–3.48) <0.001 -
Quantity of smoking
  1–10 cigarettes/day 108,145 1.00 (reference) - 39,841 1.00 (reference) - -
  11–20 cigarettes/day 491,187 1.39 (1.30–1.50) <0.001 49,727 1.37 (1.14–1.65) <0.001 0.143
  >20 cigarettes/day 691,498 2.03 (1.89–2.17) <0.001 21,049 1.69 (1.36–2.09) <0.001 -
Quantity of smoking in former smokers
  1–10 cigarettes/day 48,946 1.00 (reference) - 11,361 1.00 (reference) - -
  11–20 cigarettes/day 200,661 1.43 (1.23–1.66) <0.001 10,334 1.56 (0.92–2.64) 0.102 0.180
  >20 cigarettes/day 264,153 2.17 (1.88–2.51) <0.001 4416 1.49 (0.80–2.77) 0.204
Quantity of smoking in current smokers
  1–10 cigarettes/day 59,199 1.00 (reference) - 28,480 1.00 (reference) - -
  11–20 cigarettes/day 290,526 1.43 (1.32–1.55) <0.001 39,393 1.33 (1.09–1.62) 0.005 0.208
  >20 cigarettes/day 427,345 2.18 (2.03–2.36) <0.001 16,633 1.74 (1.39–2.19) <0.001 -
Pack-year
  0–9 186,132 1.00 (reference) - 64,184 1.00 (reference) - -
  10–19 362,880 1.40 (1.28–1.53) <0.001 28,880 1.70 (1.40–2.08) <0.001 -
  20–29 345,016 1.91 (1.76–2.07) <0.001 10,844 1.89 (1.45–2.41) <0.001 0.470
  ≥30 396,802 2.91 (2.69–3.15) <0.001 6709 2.59 (2.05–3.28) <0.001 -
Pack-year in former smokers
  0–9 118,093 1.00 (reference) - 18,433 1.00 (reference) - -
  10–19 159,305 1.24 (1.08–1.42) <0.001 4817 2.37 (1.35–4.14) <0.001 -
  20–29 109,053 1.75 (1.53–2.00) <0.001 1656 3.15 (1.62–6.10) <0.001 0.026
  ≥30 127,309 2.80 (2.48–3.16) <0.001 1205 2.26 (1.08–4.76) 0.042 -
Pack-year in current smokers
  0–9 68,039 1.00 (reference) - 45,751 1.00 (reference) - -
  10–19 203,575 1.24 (1.10–1.39) <0.001 24,063 1.54 (1.24–1.90) <0.001
  20–29 235,963 1.50 (1.34–1.67) <0.001 9188 1.66 (1.29–2.15) <0.001 0.379
  ≥30 269,493 2.29 (2.06–2.54) <0.001 5504 2.52 (1.96–3.23) <0.001
Years since cessation in former smokers
  Current smoker 777,070 1.00 (reference) - 84,506 1.00 (reference) - -
  0–4 156,560 0.69 (0.65–0.73) <0.001 11,981 0.65 (0.47–0.90) 0.009 0.469
  ≥5 357,200 0.38 (0.36–0.40) <0.001 14,130 0.46 (0.33–0.64) <0.001 -

N, number; HR, hazard ratio; CI, confidence interval. 1 Adjusted for age; alcohol consumption; physical activity; body mass index; family history of cancer; and medical history of lung diseases including emphysema, chronic pulmonary obstructive disease, pneumoconiosis, and interstitial pulmonary disease.