In the context of an aging society, the number of elderly Alzheimer's disease and related dementia (ADRD) patients in China has been increasing year by year, placing a heavy caregiving burden on their primary family caregivers and garnering extensive attention both domestically and internationally.
This study aims to analyze the burden of ADRD among Chinese elderly individuals, explore the influence of age, period, and cohort factors on its incidence and prevalence, and predict its incidence post-2021, providing a basis for the development of preventive and curative measures by relevant authorities.
Using ADRD data from the Global Burden of Disease Study 2021 (GBD 2021), we extracted the crude incidence rate, crude prevalence rate, crude mortality rate, and crude DALY rate of ADRD among Chinese elderly individuals from 1992 to 2021. After age standardization, we analyzed trends using the Joinpoint regression model and calculated the annual percentage change (APC) and average annual percentage change (AAPC). Age-period-cohort models were used to analyze the effects of age, period, and cohort factors on the incidence and prevalence of ADRD, while Bayesian age-period-cohort models were employed to predict incidence rates from 2022 to 2030.
The age-standardized incidence and prevalence of ADRD among China's elderly population from 1992 to 2021 showed an overall increasing trend (incidence: AAPC=0.57%, 95%CI=0.41%-0.72%; prevalence: AAPC=0.64%, 95%CI=0.60%-0.68%). The growth rate of standardized incidence was higher in men than in women (AAPC: 0.63% vs. 0.60%), while the growth in standardized prevalence was higher in women than in men (AAPC: 0.68% vs. 0.66%). The standardized mortality rate decreased across three intervals (1992-2019: APC of -0.11%, -0.41%, and -0.08%) but increased from 2019 to 2021 (APC=1.96%, 95%CI=0.78%-3.15%). The effects of age, period, and cohort factors on ADRD incidence and prevalence were significant. Specifically, the risk of incidence and prevalence increased with age in both men and women over 60 years old, with individuals aged 95 years and older having 13.24 and 13.53 times higher risk of incidence in men and women, respectively, compared to the 60-64 age group. The corresponding prevalence risks were 13.55 and 16.05 times higher. Over time, the risk increased, peaking during 2017-2021. In contrast, cohort effects revealed a progressive decrease in risk with later birth cohorts. By 2030, the standardized incidence rate is projected to increase by approximately 43.62% in women (from 1 267.77 to 1 820.80 per 100 000) and by 36.52% in men (from 920.22 to 1 256.30 per 100 000). Additionally, the number of ADRD cases among men and women was expected to rise significantly, with increases of 89.74% and 105.06%, respectively, between 2021 and 2030.
The increasing burden of ADRD in China's elderly population highlights the need for effective measures, particularly to protect elderly women.
In recent years, the incidence of colorectal cancer has been on the rise in low- and middle-income countries. Early-onset colorectal cancer (EOCRC), defined as colorectal cancer occurring in patients under 50 years of age, continues to see an increasing incidence. However, there is currently a lack of relevant epidemiological trends, which may hinder precise prevention, control strategies, and resource allocation for EOCRC.
To analyze the trends in the disease burden of EOCRC and the major risk factors for EOCRC in China and Global across different genders from 1990 to 2021 and predict the incidence and mortality rates of EOCRC for different genders in China and global from 2022 to 2046.
The incidence, mortality and disability adjusted life year (DALY) rate of colorectal cancer diagnosed between the ages of 14 and 49 in China and Global from 1990 to 2021 were collected using the Global Burden of Disease Database 2021. Age-standardized incidence rates (ASIR), age-standardized mortality rates (ASMR), and age-standardized disability-adjusted life years (ASDR) were utilized to analyze the disease burden of EOCRC and its major risk factors by gender in China and global. The Joinpoint model was used to calculate the annual percentage change (APC) and the average annual percentage change (AAPC) to reflect the trends in disease burden changes. Furthermore, the Bayesian age-period-cohort (BAPC) model was used to predict the incidence and mortality rates of EOCRC for different genders in China and globally from 2022 to 2046.
In 2021, the ASIR, ASMR, ASDR for Chinese males in EOCRC were 13.39/100 000, 4.26/100 000, 220.59/100 000, the ASIR, ASMR, ASDR for Chinese females in EOCRC in were 5.75/100 000, 1.68/100 000, 87.29/100 000. In 2021, the ASIR, ASMR, ASDR for global males in EOCRC were 6.11/100 000, 2.29/100 000, and 115.58/100 000, the ASIR, ASMR, ASDR for Chinese females in EOCRC were 4.17/100 000, 1.57/100 000, and 79.49/100 000. The AAPC for ASIR of males in China and global was 2.09% (95%CI=1.76%-2.43%) and 0.73% (95%CI=0.61%-0.84%), while for females in China, it was 0.31% (95%CI=0.04%-0.59%), all indicating an upward trend (P<0.05). The AAPC for the ASMR for males in China and global was -0.28% (95%CI=-0.51% to -0.05%) and -0.54% (95%CI=-0.68% to -0.40%), the AAPC was -2.22% (95%CI=-2.47% to -1.97%) in Chinese female and -1.25% (95%CI=-1.37% to -1.13%) in global female, all indicating a downward trend (P<0.05). The trend of ASIR trend for global females exhibited fluctuations, with AAPC of -0.09% (95%CI=-0.22% to 0.04%) (P>0.05). The trend of ASDR for Chinese male showed an inverted "V" shape, with AAPC of -0.20% (95%CI=-0.45% to 0.04%) (P>0.05). By 2046, the predicted ASIR and ASMR for Chinese male are expected to be 28.46/100 000 and 4.80/100 000. For females in China, these rates are projected to be 7.41/100 000 and 1.23/100 000. Globally, the ASIR and ASMR for males are forecasted to be 5.90/100 000 and 1.62/100 000, while for females, the rates are expected to be 3.06/100 000 and 1.05/100 000.
The disease burden of EOCRC in both males and females in China is severe and exceeds the global average, exhibiting significant gender disparities. There is a need to deepen the focus on the gender disparities associated with EOCRC and to implement targeted prevention and control measures. Additionally, drawing on global prevention and treatment experiences can provide a valuable reference for policy formulation.
