RT Journal Article
SR Electronic
T1 Secondhand smoke exposure and oral cancer risk: a systematic review and meta-analysis
JF Tobacco Control
JO Tob Control
FD BMJ Publishing Group Ltd
SP 597
OP 607
DO 10.1136/tobaccocontrol-2020-056393
VO 31
IS 5
A1 Lorena C. Mariano
A1 Saman Warnakulasuriya
A1 Kurt Straif
A1 Luís Monteiro
YR 2022
UL http://tobaccocontrol.bmj.com/content/31/5/597.abstract
AB Objectives Inhalation of secondhand smoke (SHS) causes several diseases, including lung cancer. Tobacco smoking is a known cause of oral cancer; however, it has not been established whether SHS also causes oral cancer . The aim of this study was to evaluate the potential association between SHS exposure and the risk of oral cancer.Methods A systematic review and meta-analysis study (following the PRISMA guidelines) was developed to examine the studies reporting on the associations of SHS and the risk of oral cancer, employing a search strategy on electronic databases (PubMed, Web of Science, Scopus, Cochrane Library, Open Grey, and ProQuest databases for dissertations) until 10 May 2020. Meta-analyses and sensitivity analyses were performed using random-effect models. The protocol was registered in PROSPERO (CRD42020189970).Results Following the application of eligibility criteria, five studies were included, comprising a total of 1179 cases and 5798 controls, with 3452 individuals exposed and 3525 individuals not exposed to SHS. An overall OR of 1.51 (95% CI 1.2o to 1.91, p=0.0004) for oral cancer was observed, without significant heterogeneity (I2=0%, p=0.41). The duration of exposure of more than 10 or 15 years increased the risk of oral cancer (OR 2.07, 95% CI 1.54 to 2.79, p<0.00001), compared with non-exposed individuals, without significant heterogeneity (I2=0%, p=0.76).Conclusions This systematic review and meta-analysis supports a causal association between SHS exposure and oral cancer. Our results could provide guidance to public health professionals, researchers, and policymakers to further support effective SHS exposure prevention programs worldwide.Data are available in a public, open access repository. Data sharing not applicable as no datasets generated and/or analysed for this study. Data are available upon reasonable request. Additional information is provided in supplemental documents.