Background: Emerging interest surrounds the role of environmental factors, notably exposure to light at night (LAN), as a potential cause of cancer. The aim of this study was to conduct a systematic review and, if possible, meta-analysis of observational studies on LAN and cancer risk of multiple types. Methods: A systematic literature search in PubMed, Web of Science, and Embase, spanning from inception to May 2023, was conducted. Studies focusing on the association between LAN exposure and cancer risk in adult populations were included. We used random effects models to calculate pooled risk estimates (RR) and 95% confidence intervals (CI). We assessed study quality using the Risk of Bias in Non-randomized Studies of Interventions. Results: Among 8492 initially identified studies, 26 met the inclusion criteria (13 were case–control and 13 were cohort studies). These studies were published from 2001 to 2023 and assessed diverse cancer types in North America, Asia, Europe, and Australia. Except for breast cancer, there was a paucity of site-specific cancer studies. In the meta-analysis of 19 breast cancer studies, higher exposure to indoor (summary RR, 1.08; 95% CI 1.01–1.15) and outdoor (summary RR, 1.10; 95% CI, 1.04–1.15) LAN were associated with increased risk. After excluding one low-quality study, the results were unchanged. Conclusions: We found a positive association between LAN exposure and breast cancer risk in women. However, data are lacking for other cancer types, and further studies are required to better understand the role of LAN on cancer.
背景：环境因素，特别是夜间光照暴露，作为癌症的潜在诱因正受到越来越多的关注。本研究旨在对夜间光照与多种癌症风险的观察性研究进行系统性综述，并在可能的情况下进行荟萃分析。方法：系统检索了PubMed、Web of Science和Embase数据库自建库至2023年5月的文献，纳入关注成人群体夜间光照暴露与癌症风险关联的研究。采用随机效应模型计算汇总风险估计值及其95%置信区间，使用非随机干预研究偏倚风险评估工具进行质量评价。结果：在初步筛选的8492篇文献中，最终纳入26项符合标准的研究（13项病例对照研究和13项队列研究）。这些研究发表于2001年至2023年间，覆盖北美、亚洲、欧洲和澳大利亚地区，涉及多种癌症类型。除乳腺癌外，其他部位特异性癌症的研究较为缺乏。在对19项乳腺癌研究的荟萃分析中，较高的室内（汇总RR=1.08，95% CI 1.01-1.15）和室外（汇总RR=1.10，95% CI 1.04-1.15）夜间光照暴露均与风险增加相关。排除一项低质量研究后结果保持稳定。结论：研究发现女性夜间光照暴露与乳腺癌风险存在正相关关系，但其他癌症类型的数据仍显不足，需进一步研究以深入理解夜间光照在癌症发生中的作用机制。
肿瘤(癌症)患者之家