Lu Wang

Liver cancer (LC) is one of the most common causes of cancer-related deaths: this study aims to present the long-term trends and age–period–cohort effects of the incidence of and mortality from LC in China during 1990–2017. Incidence and mortality data were obtained from the Global Burden of Disease Study 2017. We determined trends in the age-standardized incidence rate (ASIR) and mortality rate (ASMR) using Joinpoint regression. An age–period–cohort (APC) analysis was performed to describe the long-term trends with intrinsic estimator methods. The ASMR decreased markedly before 2013 and increased thereafter, with overall average annual percent change (AAPC) values of −0.5% (95% confidence interval (CI): −0.6%, −0.3%) for men and −1.3% (−1.6%, −1.0%) for women during 1990–2017. The ASIR significantly increased by 0.2% (0.1%, 0.3%) in men and decreased by 1.1% (−1.2%, −1.0%) in women from 1990 to 2017. The risks of LC incidence and mortality increased with age in both genders. The period effect risk ratios (RRs) of incidence and mortality displayed similar monotonic increasing trends in men and remained stable in women. The cohort effect showed an overall downward trend and almost overlapping incidence and mortality in both genders, and later birth cohorts experienced lower RRs than previous birth cohorts. Older age, recent period, and birth before 1923 were associated with a higher risk of liver cancer incidence and mortality. The net age and period effects showed an increasing trend, while the cohort effects presented a decreasing trend in incidence and mortality risk. As China’s population aging worsens and with the popularization of unhealthy lifestyles, the burden caused by liver cancer will remain a huge challenge in China’s future.

Complications due to chronic obstructive pulmonary disease (COPD) is a leading cause of death in China and the United States (U.S.). This study aimed to investigate the long-term trends in COPD mortality in China and the U.S. using data from the Global Burden of Disease Study 2017 (GBD 2017) and explore the age, period, and cohort effects independently by sex under the age–period–cohort (APC) framework. Taking the age group 40–44 years old, the period 1992–1996, and the birth cohort 1913–1917 as reference groups, we found that the age relative risks (RRs) of COPD mortality increased exponentially in both China and the U.S., the period RRs increased in the U.S. but decreased in China; and the cohort RRs showed an overall downward trend in both China and the U.S. with the year of birth. From 1992 to 2017, the increased RRs of COPD mortality in the U.S. was mainly attributable to the increased prevalence of smoking before 1965, while the decreased RRs of COPD mortality in China was mainly attributable to reduced air pollution as well as improvements in medical technology and more accessible health services. Reducing tobacco consumption may be the most effective and feasible way to prevent COPD in China. However, we also need to pay more attention to COPD in nonsmokers in the future.

This study aimed to identify and compare the mortality trends for road injuries in China and the United States, and evaluate the contributions of age, period, and cohort effects to the trends from 1990 to 2014. Using the 2016 Global Burden of Disease Study database, the mortality trends were analyzed by joinpoint regression and age-period-cohort modeling. Overall, the mortality for road injuries was higher in China than in the United States. The mortality in China increased from 1992 to 2002 (annual percent change [APC] was 1.9%), and then decreased from 2002 to 2015 (APC_2002–2009 was 1.5%; APC_2009–2015 was 3.5%). For the United States, the mortality decreased from 1990 to 2010 (APC_1990–1997 was 1.8%; APC_1997–2005 was 0.7%; APC_2005–2010 was 4.2%). Age-period-cohort modeling revealed significant period and cohort effects. Compared with the period 2002–2004, the period risk ratios (RRs) in 2010–2014 period declined by 14.62% for China and 18.86% for the United States. Compared with the 1955–1959 birth cohort, the cohort RRs for China and the United States in the 2010–2014 cohort reduced by 47.60% and 75.94%, respectively. Period and cohort effects could not be ignored for reducing road injury mortalities.