Trends in geographical disparities for cervical cancer mortality in China from 1973 to 2013: a subnational spatio-temporal study
Abstract
Objective: This study was designed to explore the time trends in geographical variations of cervical cancer mortality in mainland China over the period 1973 to 2013, to provide subnational spatio-temporal patterns for targeted promotion of human papillomavirus vaccine in China.
Methods: Data were extracted from three national retrospective death surveys and cancer registry. The rate ratio (RR) was estimated for the aggregated data for seven geographical regions using generalized linear models to evaluate time trends in geographical disparities of cervical cancer mortality.
Results: There was a significant decrease in cervical cancer mortality in China from 1973–1975 to 2004–2005, but leveled off thereafter to 2011–2013. Compared to the period 1973–1975 the RR for the three last time periods were 0.33 [95% confidence interval (95% CI): 0.30–0.37] for 1990–1992, 0.21 (95% CI: 0.19–0.24) for 2004–2005 and 0.24 (95% CI: 0.22–0.26) for 2011–2013. Females living in the Northwest China and Central China have a high risk of mortality from cervical cancer compared to the nationwide, with the RR being 2.09 (95% CI: 1.83–2.38) and 1.26 (95% CI: 1.11–1.44) respectively, while the RRs for South China, Northeast China and Southwest China were below 1.00, indicating the lower death risk. Despite the mortality rate had increased slightly from 2004 to 2013, there was an encouraging sign that the geographical disparities in cervical cancer mortality had gradually narrowed over time across China.
Conclusions: Although cervical cancer mortality in China has reduced to very low levels, the high risk of cervical cancer in Northwest China and Central China is still noteworthy. Public health policies including the promotion of vaccine should be targeted to further reduction of geographical disparities in cervical cancer mortality.
Keywords: Cervical cancer; mortality; spatio-temporal; epidemiology; China
Methods: Data were extracted from three national retrospective death surveys and cancer registry. The rate ratio (RR) was estimated for the aggregated data for seven geographical regions using generalized linear models to evaluate time trends in geographical disparities of cervical cancer mortality.
Results: There was a significant decrease in cervical cancer mortality in China from 1973–1975 to 2004–2005, but leveled off thereafter to 2011–2013. Compared to the period 1973–1975 the RR for the three last time periods were 0.33 [95% confidence interval (95% CI): 0.30–0.37] for 1990–1992, 0.21 (95% CI: 0.19–0.24) for 2004–2005 and 0.24 (95% CI: 0.22–0.26) for 2011–2013. Females living in the Northwest China and Central China have a high risk of mortality from cervical cancer compared to the nationwide, with the RR being 2.09 (95% CI: 1.83–2.38) and 1.26 (95% CI: 1.11–1.44) respectively, while the RRs for South China, Northeast China and Southwest China were below 1.00, indicating the lower death risk. Despite the mortality rate had increased slightly from 2004 to 2013, there was an encouraging sign that the geographical disparities in cervical cancer mortality had gradually narrowed over time across China.
Conclusions: Although cervical cancer mortality in China has reduced to very low levels, the high risk of cervical cancer in Northwest China and Central China is still noteworthy. Public health policies including the promotion of vaccine should be targeted to further reduction of geographical disparities in cervical cancer mortality.
Keywords: Cervical cancer; mortality; spatio-temporal; epidemiology; China