The relationship between tobacco and breast cancer incidence: A systematic review and meta-analysis of observational studies

Abstract

BackgroundThe effect of tobacco on breast cancer (BC) is controversial. The purpose of this study was to investigate the relationship between tobacco and BC.MethodsA search was conducted in PubMed, EBSCO, Web of Science and Cochrane Library databases before February 2022. The adjusted odd ratio (OR) and corresponding 95% confidence interval (CI) were used to examine the relationship between active or passive smoking and BC risk.ResultsA total of 77 articles composed of 2,326,987 participants were included for this meta-analysis. Active (OR=1.15, 95% CI=1.11-1.20, p<0.001) and passive (OR=1.17, 95% CI=1.09-1.24, p<0.001) smoking increased the risk of BC in the female population, especially premenopausal BC (active smoking: OR=1.24, p<0.001; passive smoking: OR=1.29, p<0.001), but had no effect on postmenopausal BC (active smoking: OR=1.03, p=0.314; passive smoking: OR=1.13, p=0.218). Active smoking increased the risk of estrogen receptor-positive (ER+) BC risk (OR=1.13, p<0.001), but had no effect on estrogen receptor-negative (ER-) BC (OR=1.08, p=0.155). The risk of BC was positively associated with the duration and intensity of smoking, negatively associated with the duration of smoking cessation. Active smoking increased the risk of BC in the multiparous population (OR=1.13, p<0.001), but had no effect on the nulliparous population (OR=1.05, p=0.432), and smoking before the first birth (OR=1.22, 95% CI=1.17-1.27) had a greater impact on the risk of BC than smoking after the first birth (OR=1.08, 95% CI=1.04-1.12).ConclusionSmoking (active and passive) increased the risk of BC in women. The effect of smoking on BC was influenced by smoking-related factors (duration, intensity, years of quitting), population-related factors (fertility status), and BC subtypes.Systematic Review Registrationidentifier CRD42022322699.

The association of a combined healthy lifestyle with the risk of postmenopausal breast cancer subtypes in the Netherlands Cohort Study

“…Adherence to Mediterranean diet (aMEDr) was significantly inversely associated with hormone receptor negative breast cancer, while alcohol showed no statistically significant associations. Overall, these findings are in line with the literature [ 3 , 54 - 57 ]. While these factors (smoking, BMI, physical activity, alcohol intake, Mediterranean diet adherence) generally showed weak or modest associations with breast cancer risk—depending on ER/PR subtype-, the additive protective effect of the factors combined was stronger than those of the individual factors in the NLCS, as was also observed in other studies (e.g., [ 21 ]).…”

Association of lifestyle factors and breast cancer risk in Vietnamese women: A matched case-control study

“…We found that women who had been passively exposed to smoking were associated with an increased risk of breast cancer, which was consistent with previous studies [21][22][23]. In the Chinese population, passive smoking, operationally de ned as passive exposure to smoke in the house or workplace, was found to be associated with approximately 30-40% higher risk of breast cancer [21,22].…”

“…Similar to our study, their adverse association between passive smoking and breast cancer remained signi cant after adjusting for potential confounding effects. A meta-analysis of observational studies showed that women exposed to tobacco smoke in their childhood/adult residential/occupational in 10-20 years, 20-30 years, and >30 years had a high risk of breast cancer, with odds ratios of 1.13 (95% CI: 1.03-1.25), 1.38 (95% CI: 1.18-1.61), 1.35 (95% CI: 1.10-1.65), respectively [23]. Several biological plausibilities were proposed to add weight to tobacco's harmful effect on women's breast cancer [24][25][26][27].…”

Occupational-Related Exposure to Benzene and Risk of Breast Cancer: Systematic Review and Meta-analysis

“…The lack of heterogeneous results may be attributed to insufficient adjustments to account for confounding variables such as cigarette smoke, secondhand tobacco smoke, alcohol consumption, mutations (i.e. BRCA), family history, and other environmental toxins (He et al 2022;Jones et al 2017;Kim et al 2018;Mehrgou and Akouchekian 2016;Rumgay et al 2021).…”