Comparison of lung cancer mortality between rural and urban areas in the mainland of China from 2004 to 2018

ObjectiveTo analyze the trend of mortality from lung cancer in urban and rural areas of Chinese mainland from 2004 to 2018.

MethodsCancer cases from 2004 to 2018 coded as C33-C34 according to the International Classification of Diseases-10^th Revision （ICD-10） were collected from the Chinese national mortality surveillance system. The crude mortality rate （CMR）， age-standardized mortality （ASMR） and annual percentage change （APC） were calculated to analyze the mortality trend of lung cancer in rural and urban areas.

ResultsFrom 2004 to 2018， the CMR of lung cancer was 41.11/10⁵， and the ASMR was 27.91/10⁵， with no significant tendency of upward or downward. The CMR of lung cancer in urban areas was 46.03/10⁵， and the ASMR was 30.33/10⁵， with an APC of -0.82%. The CMR of lung cancer in rural areas was 38.54/10⁵， and the ASMR was 26.66/10⁵， with an APC of 1.73%. The difference between urban and rural CMR was significant. The CMR of lung cancer in urban eastern， central and western areas were 50.27/10⁵， 44.59/10⁵ and 40.64/10⁵， respectively. The APC of eastern and central urban areas were -1.05% and -1.08%， respectively. The CMR of lung cancer in rural eastern， central and western areas were 45.82/10⁵， 38.26/10⁵ and 28.90/10⁵， respectively， with an increasing trend. The CMR of lung cancer was significantly different between urban and rural areas of eastern， central and western areas of China. The CMR of lung cancer in urban males and females were 63.17/10⁵ and 28.42/10⁵， respectively. The CMR of lung cancer in rural males and females were 52.83/10⁵ and 23.62/10⁵， respectively. The ASMR of lung cancer in rural men and women increased by 1.18% and 1.09%， respectively. The ASMR of lung cancer in urban men and women decreased by 0.61% and 1.35%， respectively. The CMR of lung cancer between males and females in urban and rural was significantly different. The CMR rate of lung cancer increased with age， with the peak in the age group above 60 years old. The ASMR rate of lung cancer showed a decreasing trend in the group under 60 years old in both urban and rural areas. While in rural areas， the ASMR of lung cancer showed an increasing trend in the group over 60 years old. There were significant variations in lung cancer CMR between rural and urban areas in groups aged 0-19， 40-59， and over 60 years.

ConclusionThe CMR of lung cancer in China is different between urban and rural areas from 2004 to 2018， which may be affected by smoking， ageing， industrialization and gender. Identifying high-risk populations， especially those in rural areas and providing early intervention can help to reduce the mortality rate of lung cancer.