Liu Kang, Zhang Weining, Dai Zhiming, Wang Meng, Tian Tian, Liu Xinghan, Kang Huafeng, Guan Haitao, Zhang Shuqun, Dai Zhijun
Department of Oncology, Second Affiliated Hospital of Xi'an Jiaotong University.
Department of Surgical Chest and Oncology, Xian XD Group Hospital.
Cancer Manag Res. 2018 Jan 18;10:143-151. doi: 10.2147/CMAR.S144619. eCollection 2018.
Breast cancer is the most common cancer in women worldwide. The association between body mass index (BMI) and breast cancer risk has been paid more attention in the past few years, but the findings are still controversial. To obtain a more reliable conclusion, we performed a dose-response meta-analysis on 12 prospective cohort studies comprising 22,728,674 participants.
Linear and nonlinear trend analyses were conducted to explore the dose-response relationship between BMI and breast cancer risk. The summary relative risk (SRR) and 95% confidence intervals (CIs) were used to evaluate the cancer risk.
The overall results showed a weak positive association between a 5-unit increase in BMI and breast cancer risk, indicating that a 5 kg/m increase in BMI corresponded to a 2% increase in breast cancer risk (SRR: 1.02, 95% CI: 1.01-1.04, <0.001). Notably, further subgroup meta-analysis found that higher BMI could be a protective factor of breast cancer risk for premenopausal women (SRR: 0.98, 95% CI: 0.96-0.99, <0.001). In addition, the dose-response result demonstrated that there was a linear association between BMI and breast cancer risk (=0.754).
In summary, this dose-response meta-analysis of prospective cohort studies showed that every 5 kg/m increase in BMI corresponded to a 2% increase in breast cancer risk in women. However, higher BMI could be a protective factor in breast cancer risk for premenopausal women. Further studies are necessary to verify these findings and elucidate the pathogenic mechanisms.
乳腺癌是全球女性中最常见的癌症。过去几年，体重指数（BMI）与乳腺癌风险之间的关联受到了更多关注，但研究结果仍存在争议。为了得出更可靠的结论，我们对12项前瞻性队列研究进行了剂量反应荟萃分析，这些研究共纳入22,728,674名参与者。
进行线性和非线性趋势分析，以探讨BMI与乳腺癌风险之间的剂量反应关系。采用汇总相对风险（SRR）和95%置信区间（CI）来评估癌症风险。
总体结果显示，BMI每增加5个单位与乳腺癌风险之间存在微弱的正相关，这表明BMI每增加5kg/m²，乳腺癌风险相应增加2%（SRR：1.02，95%CI：1.01-1.04，P<0.001）。值得注意的是，进一步的亚组荟萃分析发现，较高的BMI可能是绝经前女性乳腺癌风险的一个保护因素（SRR：0.98，95%CI：0.96-0.99，P<0.001）。此外，剂量反应结果表明，BMI与乳腺癌风险之间存在线性关联（P=0.754）。
总之，这项前瞻性队列研究的剂量反应荟萃分析表明，女性BMI每增加5kg/m²，乳腺癌风险相应增加2%。然而，较高的BMI可能是绝经前女性乳腺癌风险的一个保护因素。需要进一步研究来验证这些发现并阐明其致病机制。
