Age-period-cohort effects on mortality from cerebrovascular disease in southern Spain

Age-period-cohort Analysis of Cardiovascular Disease Mortality in Japan, 1995-2018

OBJECTIVES

This study aimed to analyze the mortality of heart disease (HD), ischemic heart disease (IHD), and cerebrovascular disease (CeVD) through an age-period-cohort (APC) analysis.

METHODS

We used data on mortality due to cardiovascular disease from 1995 to 2018 in Japan, as determined by Vital Statistics. Age groups from 0 years to 99 years were defined by 5-year increments, and cohorts were defined for each age group of each year with a 1-year shift. We used Bayesian APC analysis to decompose the changes in the diseases' mortality rates into age, period, and cohort effects.

RESULTS

The period effects for all diseases decreased during the analyzed periods for both men and women. The cohort effects for men increased substantially in cohorts born from around 1940 to the 1970s for all types of cardiovascular diseases. The cohort effects of HD decreased in the cohorts born in the 1970s or later for both men and women. Regarding IHD and CeVD, either a non-increase or decrease of cohort effects was confirmed for cohorts born in the 1970s or later for men, but the effects for women showed a continuously increasing trend in the cohorts born in the 1960s or later.

CONCLUSIONS

The cohort effects for IHD and CeVD showed increasing trends in younger generations of women. This suggests that preventive approaches against cardiovascular diseases are needed, particularly for women.

Age-Period-Cohort Analysis of Type-Specific Stroke Morbidity and Mortality in China

BACKGROUND

Stroke has become the leading cause of death in China. This study aimed to assess the age-period-cohort (APC) effects on the long-term trends of type-specific stroke morbidity and mortality in China between 1993 and 2017.Methods and Results:The data were obtained from the Global Burden of Disease 2017 (GBD 2017) and were analyzed with the age-period-cohort framework. The net drifts of mortality were below 0 (hemorrhagic stroke [HS]: males: -1.620%, females: -3.531%; ischemic stroke [IS]: males: -1.041%, females: -3.002%), and the local drift values were below 0 in all age groups and for both genders. The net drifts of HS incidence were below 0 (males: -1.412%, females: -2.688%), while those of IS were above 0 (males: 1.425%, females: 1.117%). Period effect of mortality showed similar monotonic downward patterns for both genders, with a faster decrease for females than for males. Period effect of incidence showed a declined trend of incidence for HS, but an elevated trend for IS in both genders. After controlling for age and period effects, cohort effects on incidence found a monotonic decline trend for HS, while for IS, an elevated trend was found at first to peak during the 1950-1970 s, then declined steadily afterwards. Cohort effects on mortality showed a monotonic declined trend.

CONCLUSIONS

By using Age-Period-Cohort (APC) analysis, a disparity between HS and IS was identified. Different prevention and control strategies should be used depending on the subtypes of stroke.

Trends in cerebrovascular diseases mortality in Serbia, 1997-2016: a nationwide descriptive study

OBJECTIVES

Over the last decades, mortality from cerebrovascular diseases (CVDs) has decreased in many countries. The aim of this study was to assess the trends of CVDs mortality in Serbia.

METHODS

Descriptive epidemiological study. Age-standardised rates (ASRs) for CVDs mortality were assessed by joinpoint regression analysis to identify significant changes in trends and estimate annual per cent changes with 95% CI. The age-period-cohort analysis has been used to describe variations in mortality.

RESULTS

Over this 20-year period, there were 312 847 deaths from CVDs, with the overall average annual ASR of 148.4 per 100 000. The trend of ASRs from CVDs mortality in males in Serbia showed a significant joinpoint: rates insignificantly decreased from 1997 to 2005 by -0.8% per year (95% CI -1.7% to 0.2%) and thereafter rapidly decreased by -5.0% per year (95% CI -5.6% to -4.5%). A joinpoint for females was found in 2006: the mortality trend was first significantly decreasing by -1.0% per year (95% CI -1.9% to -0.0%) and then sharply falling down by -6.0% per year (95% CI -6.8% to -5.3%). Results of age-period-cohort analysis indicated that the relative risk for CVDs mortality showed statistically significant (p<0.05) cohort and period effects, as well as the net drift and local drifts in Serbian population. The trends in mortality for all subtypes of CVDs were similar in both sexes: trends significantly decreased for most subtypes, with the exception of a significant increase for cerebral infarction.

CONCLUSIONS

After a decade of increase, CVDs mortality rates are declining in last decade in Serbia. However, mortality rates from CVDs remain exceedingly high in Serbia. Differences in mortality trends of the stroke subtypes should be taken into account in the creation of both prevention and treatment guidelines.

Age-Period-Cohort Analysis of Stroke Mortality in China: Data From the Global Burden of Disease Study 2013

BACKGROUND AND PURPOSE

Stroke has been the leading cause of death in China. The aim of this study is to assess the long-term trends of stroke mortality in China between 1994 and 2013.

METHODS

The mortality data were obtained from the GBD 2013 (Global Burden of Disease Study 2013) and were analyzed with the age-period-cohort framework.

RESULTS

We found that the net drift was -2.665% (95% confidence interval, -2.854% to -2.474%) per year for men and -4.064% (95% confidence interval, -4.279% to -3.849%) per year for women, and the local drift values were below 0 in all age groups (P<0.05 for all) in both sexes during the period of 1994 to 2013. In the same birth cohort, the risk of death from stroke rose exponentially with age for both sexes after controlling for period deviations. The estimated period and cohort relative risks were found in similar monotonic downward patterns (significantly with P<0.05 for all) for both sexes, with more quickly decreasing for women than for men during the whole period (significantly with P<0.05 for both).

CONCLUSIONS

The decreased mortality rates of stroke in China are likely to be related to improvements in medical care and techniques, spectacular economic growth and fast urbanization, and better early life nutrition conditions of Chinese people. Besides, better education and better awareness of stroke-related knowledge in successive generations could also probably play a role.

Secular trend analysis of lung cancer incidence in Sihui city, China between 1987 and 2011

Background

With industrial and econom ic development in recent decades in South China, cancer incidence may have changed due to the changing lifestyle and environment. However, the trends of lung cancer and the roles of smoking and other environmental risk factors in the development of lung cancer in rural areas of South China remain unclear. The purpose of this study was to explore the lung cancer incidence trends and the possible causes of these trends.

Methods

Joinpoint regression analysis and the age–period–cohort (APC) model were used to analyze the lung cancer incidence trends in Sihui, Guangdong province, China between 1987 and 2011, and explore the possible causes of these trends.

Results

A total of 2,397 lung cancer patients were involved in this study. A 3-fold increase in the incidence of lung cancer in both sexes was observed over the 25-year period. Joinpoint regression analysis showed that while the incidence continued to increase steadily in females during the entire period, a sharp acceleration was observed in males starting in 2005. The full APC model was selected to describe age, period, and birth cohort effects on lung cancer incidence trends in Sihui. The age cohorts in both sexes showed a continuously significant increase in the relative risk (RR) of lung cancer, with a peak in the eldest age group (80–84 years). The RR of lung cancer showed a fluctuating curve in both sexes. The birth cohorts identified an increased trend in both males and females; however, males had a plateau in the youngest cohorts who were born during 1955–1969.

Conclusions

Increasing trends of the incidence of lung cancer in Sihui were dominated by the effects of age and birth cohorts. Social aging, smoking, and environmental changes may play important roles in such trends.