Oral Contraceptive and Glioma Risk: A Prospective Cohort Study and Meta-Analysis

Abstract

BackgroundEpidemiological evidence that glioma has a slight male predominance implies that factors associated with sex hormones may play a role in the development of glioma. The association between oral contraceptive (OC) use and glioma risk remains controversial.MethodIn the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial of 70,516 women in the USA, Cox proportional hazards regression analyses were adopted to calculate the crude and adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). Additionally, a meta-analysis combining the PLCO findings with those of other prospective cohorts was performed.ResultsDuring a mean follow-up of ~11.7 years, 110 of 70,516 women aged 50–78 years at baseline were diagnosed with glioma in PLCO studies. Compared with never users, an inverse association of borderline significance was found for OC users (HR 0.67, 95% CI 0.44–1.04, P = 0.074). Analyses assessing glioma risk according to the duration of OC use yielded no significant association. When PLCO was combined with four other prospective studies, there was an inverse association between OC use and glioma risk (HR 0.85, 95% CI 0.75–0.97, I2 = 0.0%). Further dose-response analysis showed a nonlinear, inverse relationship between OC use and glioma risk (P < 0.001).ConclusionsThis study provided some evidence of a nonlinear, inverse association between OC use and glioma risk. Future larger studies are warranted to validate this finding.

Quantitative Identification Study of Epidemic Risk in the Spatial Environment of Harbin City

“…(2) Areas with high levels of epidemic risks in Harbin are mainly distributed in the city's core area, while the risks gradually decrease from the center to the periphery, and the spatial distribution is correlated with the four major concentric circles within the study area, demonstrating that the spatial distribution of the epidemic is also affected by the city's concentric distribution. (3) This method has an important role in identifying spatial clustering of epidemic risks in Harbin and has identified the risk levels of epidemic distribution in the city, which are consistent with the high-risk positions of epidemic outbreaks in space, demonstrating the effectiveness and feasibility of this method.…”

“…Prior to the COVID-19 outbreak, many scholars had already conducted research on the prevention and control, prediction, and identification of epidemics from relevant professional perspectives. As early as 2017, Shao Piaopiao and others selected seven representative indicators such as case data, transmission media, and media quantity and used the weighted comprehensive index method to assess the risk of malaria in the sample area [3]. Afterwards, related research on various communicable diseases became more extensive, which provided a certain foundation for studying the hidden risks of urban epidemic transmission.…”