pattern for total cancer incidence because the
pattern for total cancer incidence because the individuals using 180e360 DDD sedative-hypnotics showed the highest HR for overall cancer. It is possible that the use of extreme levels of sed-atives might result in different health outcomes such as death. Lastly, in this analysis, we used prescription data; this may not exactly reflect the actual amount of drug use.
In conclusion, we found a significantly increased incidence of overall cancer among women who used sedative-hypnotic medi-cations, and several specific cancers showed increased risk among both men and women who used sedative-hypnotics. Men who used sedative-hypnotics had increased incidence of lung, brain, and prostate cancer and decreased incidence of ASP1517 and colon cancer. Women who used sedative-hypnotics had increased inci-dence of thyroid, breast, ovarian, liver, and lung cancer. Further large-population studies that include data on potential covariates are needed to confirm the relationship of overall cancer risk and risk for specific types of cancer with use of various sedative-hypnotic medications.
This study was supported by the research fund of the Mental Health Technology Development Project (Project No. HM15C1197).
This manuscript was edited by Ms. Bethanie Rammer, BioMedEdits.com, for clarity, consistency, and English-language usage. Dr. Jung is supported by the Yerby Postdoctoral Fellowship of Harvard School of Public Health.
Conflict of interest
The authors have no conflicts of interest to declare.
The ICMJE Uniform Disclosure Form for Potential Conflicts of Interest associated with this article can be viewed by clicking on the following link: https://doi.org/10.1016/j.sleep.2019.03.018.
KCD-6 codes for cancers included in the current study
Code Type of cancer
Cxx Overall cancer C15 Esophageal cancer C16 Gastric cancer C18eC20 Colorectal cancer C22 Liver cancer C33eC34 Lung cancer C50 Breast cancer C53 Utero-cervix cancer C56 Ovarian cancer C61 Prostate cancer C64 Renal cancer C70eC71 Brain cancer C73 Thyroid cancer
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