Table 4.
Multivariable Cox regression analysis*. Women diagnosed with cancer vs. non-cases** stratified by smoking status.
| Factors | Never smokers | Former smokers | Current smokers |
|---|---|---|---|
| HR (95% CI); P-value; [n, cases] | HR (95% CI); P-value; [n, cases] | HR (95% CI); P-value; [n, cases] | |
| BMI | |||
| Q1 | (ref) [58,438] | (ref) [59,289] | (ref) [64,340] |
| Q2 | 1.15 (0.81–1.63); 0.43; [521, 79] | 0.66 (0.45–0.97); 0.04; [301, 51] | 0.89 (0.60–1.33); 0.58; [240, 46] |
| Q3 | 1.15 (0.80–1.65); 0.45; [508, 78] | 0.74 (0.50–1.09); 0.13; [326, 61] | 0.86 (0.57–1.31); 0.49; [209, 40] |
| Q4 | 1.11 (0.77–1.61); 0.57; [527, 79] | 0.80 (0.55–1.16); 0.24; [354, 75] | 0.61 (0.36–1.01); 0.05; [148, 23] |
| Recreational walking | |||
| (<5 times/week) | (ref) [91,517] | (ref) [66,357] | (ref) [53,279] |
| (≥5 times/week) | 0.75 (0.58–0.96); 0.02; [1477, 203] | 1.07 (0.81–1.43); 0.63; [913, 180] | 0.96 (0.69–1.33); 0.79; [658, 120] |
| Exercise habits | (ref) | ||
| (<1 time/week) | (ref) [83,541] | (ref) [74,359] | (ref) [72,368] |
| (≥1 time/week) | 1.05 (0.81–1.36); 0.72; [1453, 211] | 0.91 (0.69–1.20); 0.49; [911, 172] | 0.85 (0.62–1.15); 0.29; [569, 101] |
| Education | |||
| School (9 years) | (ref) [207,1409] | (ref) [177,892] | (ref) [133,706] |
| High school (12 years) | 1.00 (0.75–1.33); 1.00; [439, 62] | 0.93 (0.68–1.28); 0.66; [274, 52] | 0.83 (0.55–1.25); 0.37; [186, 29] |
| University (17 years) | 1.10 (0.72–1.68); 0.66; [146, 25] | 0.75 (0.45–1.24); 0.26; [104, 17] | 1.11 (0.59–2.08); 0.75; [45, 11] |
| Childbirth | |||
| (<1 child) | (ref) [30,191] | (ref) [31,147] | (ref) [27,110] |
| (≥1 child) | 0.98 (0.67–1.43); 0.91; [1803, 264] | 0.89 (0.61–1.30); 0.55 [1123, 215] | 0.74 (0.49–1.12); 0.15; [827, 146] |
| Alcohol | |||
| (≥7 units/week) | (ref) [209,1426] | (ref) [149,785] | (ref) [112,604] |
| (≥7 units/week) | 1.04 (0.80–1.34); 0.79; [568, 85] | 1.10 (0.85–1.43); 0.47 [485, 97] | 0.97 (0.71–1.34); 0.86; [333, 61] |
| Central obesity | |||
| Q1 | (ref) [75,508] | (ref) [35,272] | (ref) [41,273] |
| Q2 | 0.79 (0.56–1.12); 0.19; [533, 66] | 1.79 (1.16–2.75); 0.008; [309, 64] | 1.25 (0.79–1.98); 0.34; [207, 37] |
| Q3 | 0.91 (0.65–1.28); 0.60; [508, 74] | 1.89 (1.23–2.93); 0.004; [324, 70] | 1.38 (0.87–2.19); 0.17; [216, 39] |
| Q4 | 1.16 (0.82–1.63); 0.40; [445, 79] | 1.90 (1.23–2.94); 0.004; [365, 77] | 1.93 (1.25–2.99); 0.003; [241, 56] |
*Analysis was conducted on the complete datasets: Never smokers, n = 1994, cases = 294; Former smoker, n = 1270, cases = 246; Current smokers, n = 937, cases = 173.
**Women with no history of cancer.
Abbreviations: BMI, Body Mass Index.