Decomposing contribution of age and non-age factors to rapid growth of lung cancer in Xuanwei over past 30 years.

Yang Chen,Wen Xu,Yize Xiao,Jing Duan,Yongfang Yang

doi:10.1186/s12889-015-2482-y

Abstract

BackgroundFrom 1973 to 2005, the lung cancer mortality in Xuanwei had increased constantly. Effect analysis of age and non-age factors on lung cancer is important for local policy-making.MethodsDemographic and death data was collected and used. Factors of lung cancer were classified into age and non-age factors. The contribution of the two factors to lung cancer was evaluated by method of decomposing the differences of mortality rate.ResultsFor males, the non-age factors were the major contributor to growth of lung cancer mortality, and 78.46 % of all growth was attributed to non-age factors. For females, the non-age factors were the absolute contributor to growth of lung cancer in 1973–1992. From 1992 to 2005, the contribution proportion had reduced to 75.39 %.ConclusionsAging was one of risk factors for lung cancer in Xuanwei, but not the main factor. It was supposed that multiple environmental risk factors were related with high growth of lung cancer in Xuanwei. Policy-making should focus on the non-age factors.

Highlights

From 1973 to 2005, the lung cancer mortality in Xuanwei had increased constantly
The accumulating evidence of epidemiologic, chemical and toxicologic studies has hypothesized that the etiology of lung cancer in Xuanwei is strongly associated with high exposure to the domestic emissions of “bituminous coal”
The ecology studies found that the commune-specific lung cancer mortality was highly related to the commune-specific percentage of homes using smoky coal before 1958 [2]

Summary

Introduction

From 1973 to 2005, the lung cancer mortality in Xuanwei had increased constantly. In 1973–1979, the age-adjusted mortality rate of lung cancer in Xuanwei (27.66 per 100 000 for men, 25.33 per 100 000 for women) was higher than that in Shanghai and Beijing (that is, 29.31 per 100 000 for men and10.81 per 100 000 for women, 14.81 per 100 000 for men and 11.31 per 100 000 for women in Shanghai and Beijing, respectively) ,and higher than that in Kunming, the capital of Yunnan (13.86 per 100 000 for men, 3.95 per 100 000 for women) [1]. Epidemiological studies in Xuanwei have found the lung cancer risk of smoky coal users was 6.05 times higher than that of smokeless coal users [6]. The retrospective cohort study showed that lung cancer alone accounted for about 40 % of all deaths before age 60 among individuals using smoky coal, and lifelong use of smoky coal compared with smokeless coal use was associated with a 36-fold increase of lung cancer mortality in men and 99-fold increase in women [7]

Methods

Results

Conclusion