Irish Amyotrophic Lateral Sclerosis Incidence: Age, Period, and Cohort Effects Using a Partial Least Squares Regression Model.

BACKGROUND AND OBJECTIVES: To investigate the underlying reasons for variability in the incidence rate of amyotrophic lateral sclerosis (ALS) within the Irish population between the years 1996 and 2021. METHODS: The Irish ALS register was used to calculate the incidence and to subsequently extract age at diagnosis (age), year of diagnosis (period), and date of birth (cohort) for all incident patients within the study period (n = 2,771). An age-period-cohort (APC) model using partial least squares regression was constructed to examine each component separately and their respective contribution to the incidence while minimizing the well-known identifiability problem of APC effects. A dummy regression model consisting of 5 periods, 19 cohorts, and 16 age groups was used to examine nonlinear relationships within the data over time. The CIs for each of these were estimated using the jackknife method. RESULTS: The nonlinear model achieved R2 of 99.43% with 2-component extraction. Age variation was evident with those in the ages 65-79 years contributing significantly to the incidence (ßmax = 0.0746, SE = 0.000410, CI 0.00665-0.00826). However, those aged 25-60 years contributed significantly less (ßmin = -0.00393, SE = 0.000291, CI -0.00454 to -0.00340). Each successive period showed an increase in the regression model coefficient suggesting an increasing incidence over time, independent of the other factors examined-an increase of ß from -0.00489 (SE = 0.000264, CI -0.00541 to -0.00437) to 0.00973 (SE = 0.000418, CI 0.0105-0.00891). A cohort effect was demonstrated showing that the contribution of those born between 1927 and 1951 contributed to a significantly greater degree than the other birth cohorts (ßmax = 0.00577, SE = 0.000432, CI 0.00493-0.00662). DISCUSSION: Using the Irish population-based ALS Register, robust age, period, and cohort effects can be identified. The age effect may be accounted for by demographic shifts within the population. Changes in disease categorization, competing risks of death, and improved surveillance may account for period effects. The cohort effect may reflect lifestyle and environmental factors associated with the challenging economic circumstances in Ireland between 1927 and 1951. Age-period-cohort studies can help to account for changes in disease incidence and prevalence, providing additional insights into likely demographic and environmental factors that influence population-based disease risk.

Birth cohort effects on diagnosed atrial fibrillation incidence: nationwide cohort study from 1980 to 2018.

BACKGROUND: The incidence of atrial fibrillation (AF) shows substantial temporal trends, but the contribution of birth cohort effects is unknown. These effects refer to the relationship between birth year and the likelihood of developing AF. We aimed to assess trends in cumulative incidence of diagnosed AF across birth cohorts and to disentangle the effects of age, birth cohort and calendar period by using age-period-cohort analyses. METHODS: In a Danish nationwide population-based cohort study, 4.7 million individuals were selected at a given index age (45, 55, 65 and 75 years) free of AF and followed up for diagnosed AF. For each index age, we assessed trends in 10-year cumulative incidence of AF across six 5-year birth cohorts. An age-period-cohort model was estimated using Poisson regression with constrained spline functions collapsing data into 1-year intervals across ages and calendar years. RESULTS: Cumulative incidence of AF diagnosis increased across birth cohorts for all index ages (ptrend<0.001). Compared with the first birth cohort, the diagnosed AF incidence rate ratio in the last birth cohort was 3.0 (95% CI 2.9 to 3.2) for index age 45 years, 2.9 (2.8 to 3.0) for 55 years, 2.8 (2.7 to 2.8) for 65 years and 2.7 (2.6 to 2.7) for 75 years. Age-period-cohort analyses showed substantial birth cohort effects independent of age, with no clear period effect. Compared with individuals born in 1930, the diagnosed AF incidence rate was 0.125 smaller among individuals born in 1885 and was four times larger among individuals born in 1975. CONCLUSION: Substantial birth cohort effects, independent of age and calendar period, influence trends in diagnosed AF incidence.

Age-period-cohort effects on incidence trends of childhood leukemia from four population-based cancer registries in Colombia.

BACKGROUND: Childhood leukemia (CL) is the most prevalent form of pediatric cancer on a global scale. However, there is a limited understanding of the dynamics of CL incidence in South America, with a specific knowledge gap in Colombia. This study aimed to identify trends in CL incidence and to analyze the effects of age, period, and birth cohort on the risk of leukemia incidence in this population. METHODS: Information on all newly diagnosed leukemia cases (in general and by subtype) among residents aged 0-18 years and living in the serving areas of population-based cancer registries of Cali (2008-2017), Bucaramanga (2000-2017), Manizales (2003-2017), and Pasto (1998-2018). Estimated annual percent changes (EAPC) in incidence over time and potential changes in the slope of these EAPCs were calculated using joinpoint regression models. The effects of age, period, and cohort in CL incidence trends were evaluated using age-period-cohort models addressing the identifiability issue through the application of double differences. RESULTS: A total of 966 childhood leukemia cases were identified. The average standardized incidence rate (ASIR) of leukemia was calculated and expressed per 100,000 person-years - observing ASIR of 4.46 in Cali, 7.27 in Bucaramanga, 3.89 in Manizales and 4.06 in Pasto. Concerning CL trends there were no statistically significant changes in EAPC throughout the different periods, however, when analyzed by leukemia subtype, statistically significant changes were observed in the EAPC for both ALL and AML. Analysis of age-period-cohort models revealed that age-related factors significantly underpin the incidence trends of childhood leukemia in these four Colombian cities. CONCLUSIONS: This study offers valuable insights into the incidence trends of childhood leukemia in four major Colombian cities. The analysis revealed stable overall CL incidence rates across varying periods, predominantly influenced by age-related factors and the absence of cohort and period effects. This information is useful for surveillance and planning purposes for CL diagnosis and treatment in Colombia.

Latina paradox in Spain? Arrival-cohort effects on the birthweight of newborns of Latina mothers.

This study analyses the arrival-cohort effects on the newborn birthweight of Latina women residing in Spain. First, it has been tested whether women of Latin American origin in Spain have an advantage in terms of birth outcomes, a pattern previously documented in the United States and referred to as the 'Latin American paradox'. Second, it has been examined whether this health advantage of Latina mothers varies by arrival cohort.A novel database provided by the Spanish National Statistics Office that links the 2011 Census with Natural Movement of the Population records from January 2011 to December 2015 has been used. Poisson regression models were applied to test for differences in the incidence rates of low birthweight (LBW) and high birthweight (HBW) among children of Latina and native mothers, controlling for various demographic, socio-economic, and birth characteristics.Two distinct arrival-cohort effects on perinatal health were observed. On one hand, first-generation Latina women were found to be at a lower risk of giving birth to LBW infants; however, they experienced a higher incidence of HBW during the study period. Second, Latina women of 1.5 generation, likely stressed by increased exposure to the receiving country, exhibited adverse birthweight results.

Trends and age-period-cohort effect on dental caries prevalence from 2008 to 2019 among Brazilian preschoolers.

This study aimed to evaluate trends in the prevalence of dental caries in preschool children and associated factors considering different time variations. This is a time series study performed using data from three cross-sectional studies with pre-school children from southern Brazil in 2008, 2013 and 2019. This children group was born between the years of 2003 to 2018. Dental caries was evaluated by decayed, missing and filled deciduous teeth (dmft index). Demographic, socioeconomic, behavioural and psychosocial variables were also collected. Chi-square test for trends and a hierarchical age-period-cohort (HAPC) analysis using multilevel Poisson regression model for testing the associations between predictor variables and dental caries experience were used. A total of 1,644 pre-school children participated in all surveys. There was a significant difference in caries experience considering all APC effects. The prevalence of dental caries was 25.0% in 2008, 16.3% in 2013, and 19.4% in 2019 (p < 0.01) and no statistical difference was observed. An age effect showed that older children were more likely to experience dental caries. Considering the cohort effect, there is a significant difference between the generations, mainly between 2003 and 2018. Household income, use of dental services, and parent's perception of child oral health were associated with dental caries experience no matter the time variation. Despite recent declines in dental caries prevalence among preschool children, caries levels increased with age and social inequalities persisted through the years, indicating a need of reviewing the policies to reduce the burden of this oral disease.

Examining age, period and cohort effects in attitude change to childhood vaccinations in a representative New Zealand survey: a multiyear cohort-sequential growth modelling study.

OBJECTIVES: Vaccinations are an important preventative measure in reducing the spread of infectious diseases worldwide. However, concerns of undervaccination during childhood have become increasingly common. The current study aims to investigate changes in attitudes towards childhood vaccinations prior to the COVID-19 pandemic using a national sample from New Zealand. DESIGN: Age-based, period-based, and cohort-based changes were assessed using cohort-sequential latent growth modelling in 11 overlapping birth cohorts, which spanned the ages of 23-79 years. SETTING AND PARTICIPANTS: Data were taken from the New Zealand Attitudes and Values Study where 58 654 adults completed at least one wave across a 7-year period (2013 and 2015-2019). RESULTS: The period-based and cohort-based models fit the data equally well (χ2(282)=8547.93, p<0.001, comparative fit index, CFI=0.894, root mean square error of approximation, (RMSEA)=0.074, standardised root mean square residual, SRMR=0.105; χ2(273)=8514.87, p<0.001, CFI=0.894, RMSEA=0.075, SRMR=0.105, respectively) suggesting societal factors contribute to childhood vaccination attitudes. Additionally, the findings suggest attitudes towards childhood vaccinations were becoming increasingly more positive in all birth cohorts (ps<0.001), with younger and older birth cohorts exhibiting even positive attitudes compared with middle-aged cohorts. CONCLUSION: Overall, both the cohort-based and period-based models reveal changes in vaccination attitudes suggesting that even prior to the COVID-19 pandemic, societal influences had an impact on attitudes towards childhood vaccination.

Three decades of infant motor development: Cohort effects in motor skill onsets.

Infant motor development is affected by the sociocultural context in which it takes place. Because societal and cultural practices are dynamic, this exploratory study examined whether the ages at which infants typically learned to crawl, cruise, and walk changed over the past 3 decades. We compiled archival data from 1,306 infants born between January 31, 1992, and December 10, 2021. Parents originally reported milestone onsets in interviews and by using diaries. For each motor milestone, a linear regression model predicted the onset age using birth date. Segmented regression analyses inspected changes in slopes over time. Covariates included rural/urban housing, gestation age, season of birth, and birth weight. Infants' average crawling, cruising, and walking onset ages changed over time. After controlling for the covariates, infants' crawling onset age steadily increased until 2012, after which crawling onset age decreased. Infants' cruising onset age increased from 1991 to 2001, after which cruising onset age remained stable. After controlling for the covariates, infants' walking onset increased until 2015, after which walking onset age decreased. Thus, when infants were born explained a small but significant amount of variability in infant motor skill onset. While the current study showed that motor development changed over the years, motor development is just a model system for development more generally: Cohort effects may be pervasive across developmental domains. Using motor development as a model system for studying change suggests that generational effects due to a changing society may be pervasive across developmental domains. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Changing epidemiology of colorectal cancer - birth cohort effects and emerging risk factors.

Incidence and mortality of colorectal cancer (CRC) are increasing worldwide, suggesting broad changes in the epidemiology of CRC. In this Review, we discuss the changes that are becoming evident, including trends in CRC incidence and mortality by age and birth cohort, and consider the contributions of early-life exposures and emerging risk factors to these changes. Importantly, incidence of CRC has increased among people born since the early 1950s in nearly all regions of the world. These so-called birth cohort effects imply the involvement of factors that influence the earliest stages of carcinogenesis and have effects across the life course. Accumulating evidence supports the idea that early-life exposures are important risk factors for CRC, including exposures during fetal development, childhood, adolescence and young adulthood. Environmental chemicals could also have a role because the introduction of many in the 1950s and 1960s coincides with increasing incidence of CRC among people born during those years. To reverse the expected increases in the global burden of CRC, participation in average-risk screening programmes needs to be increased by scaling up and implementing evidence-based screening strategies, and emerging risk factors responsible for these increases need to be identified.

Age, period and cohort effects on gastric cancer mortality in Spain, 1980-2021.

BACKGROUND: this study aimed to evaluate the effects of age, time period and cohort (A-P-C) on gastric cancer (GC) mortality in Spain from 1980 to 2021. METHODS: an ecological trend study was performed (with aggregated data obtained from the Spanish National Statistics Institute (INE). Joinpoint regression software was used to estimate rates by sex and age group (< 35, 35-64, > 64 years) and mortality trends. The National Cancer Institute A-P-C tools were used to assess the effects of age, time of death and birth cohort. RESULTS: GC mortality rates in Spain decreased significantly in both sexes. In the under-35 age group, rates were stable after an initial significant decline. In the 35-64 age group, the decline was more pronounced in males than in females. In the 65+ age group, rates fell significantly for both sexes, but more so for females than for males. The net drift and local drift also showed significant decreases across all age groups from 24 years onwards. GC mortality rates increased with age and decreased with calendar time and successive birth cohorts, regardless of sex. The ratio of age-specific rates between males and females increased with age, and birth cohort relative risk estimates followed a steady downward trend until the mid-1970s, after which the decline stabilized. The relative risk decreased for both sexes, with a more pronounced decrease in males. CONCLUSION: GC mortality rates in Spain have been decreasing over time and across successive birth cohorts, with a stabilizing trend observed for those under 35 years of age.

Mortality related to HCV and other chronic liver diseases in Veneto (Italy), 2008-2021: Changes in trends and age-period-cohort effects.

BACKGROUND AND AIMS: The objective of this study was to assess the impact of the COVID-19 pandemic and direct-acting antiviral (DAA) agents on mortality related to chronic liver diseases (CLD). METHODS: Age-standardized mortality rates were computed based on CLD as the underlying cause of death (UCOD) and as any mention in death certificates (multiple causes of death-MCOD). Time trends in age-standardized mortality rates were investigated using generalized estimation equation models. Additionally, we conducted age, period, and birth cohort (APC) analyses on CLD-related mortality associated with alcohol and hepatitis C virus (HCV). RESULTS: Between 2008 and 2021, among residents in the Veneto region (Northeastern Italy) aged ≥35 years, there were 20 409 deaths based on the UCOD and 30 069 deaths based on MCOD from all CLD. We observed a 4% annual decline in age-standardized MCOD-based mortality throughout 2008-2021, with minor peaks corresponding to COVID-19 epidemic waves. Starting in 2016, the decline in HCV-related mortality accelerated further (p < .001). A peak in HCV-related mortality in the 1963-1967 birth cohort was observed, which levelled off by the end of the study period. Mortality related to alcoholic liver disease declined at a slower pace, becoming the most common aetiology mentioned in death certificates. CONCLUSIONS: The study demonstrates a significant decrease in HCV-related mortality at the population level in Italy with the introduction of DAAs. Continuous monitoring of MCOD data is warranted to determine if this favourable trend will continue. Further studies utilizing additional health records are needed to clarify the role of other CLD etiologies.

Trends in the mortality of diabetes in Mexico from 1998 to 2022: a joinpoint regression and age-period-cohort effect analysis.

OBJECTIVE: The purpose was to analyze age-standardized trends in diabetes mortality rates (DMR) from 1998 to 2022, stratified by sex and Mexican state, and the effects attributable to age, period, and cohort by sex. STUDY DESIGN: Joinpoint regression and age-period-cohort effect analysis. METHODS: Based on the tenth revision of the International Classification of Diseases, E11, E12, E13, and E14 codes of the death certificate, a daily record of mortality was extracted from the death certificate attributable to diabetes as the main cause. From 1998 to 2022, sexes and ages (≥20 years) were used to calculate the crude mortality rates and standardized at the national and Mexican state levels. Additionally, the age-period-cohort model was used to examine age, period, and cohort effects. RESULTS: From 1998 to 2005, the age-adjusted DMR increased by 3.6% (95% confidence interval [CI]: 2.7, 4.5) for the total population, as shown by the joinpoint regression analysis at a national level; from 2017 to 2020, it increased by 7.4% (95% CI: 0.6, 14.8). The DMR with the highest increase during the study period came mainly from states in the country's southeastern region, 2.3% to 3.7% per year. The net age and period effects showed that mortality increased with advancing age and with going time, respectively; and the net cohort effect revealed that mortality increased in more recent birth cohorts, mainly in men Rate Ratio (RR) = 2.37 (95% CI: 2.29, 2.46) vs RR = 1.13 (95% CI: 1.09, 1.17). CONCLUSION: The DMR increased among older age groups. The period effect showed that mortality increased over time. Furthermore, the cohort effect showed that mortality increased in more recent birth cohorts, especially among men.

Secular trends in the incidence of major depressive disorder and dysthymia in China from 1990 to 2019.

BACKGROUND: Depression is increasingly recognized as a worldwide serious, public health concern. A better understanding of depression is important for advancing its management and learning the difference between major depressive disorder (MDD) and dysthymia. Our aim is to conduct a concurrent analysis of the trends of both MDD and dysthymia in China. METHODS: The data on depression from 1990 to 2019 were collected from the Global Burden of Disease Study 2019 (GBD 2019). To determine the average annual percent changes (AAPC) and relative risks (RRs), joinpoint regression and the age-period-cohort models were employed, respectively. RESULTS: The incidence number of MDD and dysthymia continuously increased in China from 1990 to 2019, however, the age-standardized rates (ASR) had a decreasing trend in both men and women. The results from joinpoint regression showed that a declining trend was presented in young people (< 50 years) but an increased trend in the elderly (≥ 50 years) both in men and women, during 1990-2019. Age is the most influential factor for MDD and dysthymia. Age RRs for MDD incidence had an overall increasing trend with age. Period RR in MDD presented a U-shaped pattern, while Cohort RRs presented an inverted U-shaped pattern. On the other hand, RRs in dysthymia for period and cohort effects had no statistical significance, only the age effect presented an inverted U-shaped pattern. CONCLUSIONS: The disparities in trends observed between MDD and dysthymia during the period of 1990-2019 indicated the significance of distinguishing between these two disorders. The age, period and cohort effects all had a greater impact on MDD than on dysthymia, and age effects presented different influential patterns in these two. To alleviate the burden of depressive disorders in China, proactive measures need to be implemented, with particular attention to the elderly population.

Analysis of age, period, and birth cohort effects on suicide mortality in Brazil and the five major geographic regions.

OBJECTIVE: Estimate the effects of age, period, and birth cohort on suicide mortality in Brazil by major geographic region in the overall population and by sex. METHODS: This was a time trend ecological study. National and regional suicide mortality data from 1981 to 2020 were analyzed for the overall population and by sex. Age, period, and cohort effects were calculated with a Poisson regression model using estimable functions with the Epi package of the R statistical program, version 4.2.1. RESULTS: There were 272,716 suicides in individuals ranging from 20 to 79 years old. In the overall population, the age model-adjusted suicide mortality rates showed an upward pattern for Brazil. The most recent cohort showed the highest associated risk, 1.67 (95%CI 1.63; 1.71), while for the reference period, it was the highest risk among all the periods. CONCLUSIONS: Suicide mortality rates have shown an upward trend with advancing age in both men and women in the Brazilian population. However, the behavior of the period effect and cohort depends on the population analyzed and regional distribution.

Radially varying viscosity and entropy generation effect on the Newtonian nanofluid flow between two co-axial tubes with peristalsis.

To examine the peristaltic motion of a Newtonian fluid through an axisymmetric tube, many writers assume that viscosity is either a constant or a radius exponential function in Stokes' equations. In this study, viscosity is predicated on both the radius and the axial coordinate. The peristaltic transport of a Newtonian nanofluid with radially varying viscosity and entropy generation has been studied. Under the long-wavelength assumption, fluid flows through a porous media between co-axial tubes, with heat transfer. The inner tube is uniform, while the outer tube is flexible and has a sinusoidal wave travelling down its wall. The momentum equation is solved exactly, and the energy and nanoparticle concentration equations are solved using the homotopy perturbation technique. Furthermore, entropy generation is obtained. The numerical results for the behaviours of velocity, temperature, and nanoparticle concentration, as well as the Nusselt number and Sherwood number with physical problem parameters, are obtained and graphically depicted. It is discovered that as the values of the viscosity parameter and the Prandtl number rise, so does the value of the axial velocity. Temperature values decrease as the wave amplitude and radiation parameter increase. Furthermore, at high values of the dependent viscosity parameter, the fluid nanoparticle gains more active energy and can move more freely, which is the main idea behind crude oil refinement. This physical modelling is essential for some physiological flows, such as the flow of stomach juice during the insertion of an endoscope.

Stomach cancer incidence trends in selected Latin America countries: Age, period, and birth-cohort effects.

BACKGROUND: to explore the age, period, and birth-cohort effects on stomach cancer incidence trends during 3 decades in selected Latin American countries. METHODS: a time-trend study was performed using Cancer Incidence in Five Continents data from high-quality population-based cancer registries(PBCRs) in Latin American countries. Crude and age-standardized incidence rates(ASRIs) were calculated. Time trends in ASRIs were assessed using the average annual percentage change(AAPC). Age-period-cohort effects were estimated by Poisson regression for individuals aged between 20 and 79 years with stomach cancer informed by PBCRs from 1983 to 2012 in Cali(Colombia); from 1982 to 2011 in Costa Rica; and from 1988 to 2012 for Goiania(Brazil) and Quito(Ecuador). The goodness-of-fit model was tested using the deviance of the models. RESULTS: a decrease in age-standardized incidence rates was observed for both genders in all populations covered by PBCRs, except for young men from Cali(AAPC 3.89 95 %IC: 1.32-7.29). The age effect was statistically significant in all areas, and the curve slope reached peaks in the older age groups. The cohort effect was observed in all PBCRs. Regarding the period effect, an increased ratio rate was observed for both genders in Costa Rica(1997-2001 women RR 1.11 95 %CI: 1.05-1.17; men RR 1.12 95 %CI: 1.08-1.17) and Goiânia(2003-2007 women RR 1.21 95 %CI: 1.08-1.35; men RR 1.09 95 %CI: 1.01-1.20), while Quito(1998-2002 women RR 0.89 95 %CI: 0.81-0.98; men RR 0.86 95 %CI: 0.79-0.93) presented a decrease. CONCLUSION: the present study showed a decreasing gastric cancer trend for over the past 30 years with gender and geographic variations. Such a decrease seems to be mainly a result of cohort effects, suggesting that the economic market opening process led to changes in the risk factor exposures over successive generations. These geographic and gender variations may reflect cultural/ethnic/gender differences and differences in dietary and smoking rate patterns. However, an increased incidence was observed for young men in Cali, and additional studies are needed to determine the cause of the increasing incidence in this group.

Cohort Effects in Alzheimer's Disease Trials: An Empirical Assessment Utilizing Data from the Alzheimer's Disease Cooperative Study.

BACKGROUND: Cohort effects in study populations can impact clinical trial conclusions and generalizability, particularly in trials with planned interim analyses. Long recruitment windows may exacerbate these risks in Alzheimer's disease (AD) trials. OBJECTIVES: To investigate the presence of cohort effects mild-to-moderate AD trials. DESIGN: Retrospective analysis using pooled participant-level data from nine randomized, placebo-controlled trials conducted by the Alzheimer's Disease Cooperative Study (ADCS). SETTING: Trials were multicenter studies conducted by an academic trial network. PARTICIPANTS: The trials enrolled participants with mild, mild-to-moderate, or moderate AD who were over age 50 and had mini mental state exam scores between 12 and 26. Interventions/Exposure: We defined a participant's site-standardized enrollment time as the number of days between their screening date and the first screening date among randomized participants at their site within their study. MAIN OUTCOME(S) AND MEASURE(S): Our primary outcome was the 12-month change in the AD assessment scale - cognitive subscale (ADAS-Cog). Secondary outcomes were participant demographics and time to study discontinuation. RESULTS: The pooled sample consisted of N=2,754 at baseline with N=2,191 participants completing a 12-month visit. We found no meaningful differences in the distributions of sex, race and ethnicity, age, years of education or baseline ADAS-Cog score across enrollment time. We found a significant association between enrollment time and 12-month change in ADAS-Cog, with participants enrolling 100 days later tending to experience an increase on the ADAS-Cog of 0.16 points greater (reflecting greater cognitive decline; 95% CI: (0.021, 0.294), p = 0.02), after controlling for potential confounding factors. CONCLUSION: We found minimal evidence of clinically relevant cohort effects in ADCS trials. Our results reinforce the original findings of these trials.

Cohort effects of women's mid-life binge drinking and alcohol use disorder symptoms in the United States: Impacts of changes in timing of parenthood.

BACKGROUND AND AIMS: Alcohol use is increasing among women in mid-life concurrently with societal changes in timing of parenthood and changing cultural norms, which may influence alcohol use. The aim of this study was to determine if age of first parenting was associated with excessive drinking [i.e. past 2-week binge drinking and past 5-year alcohol use disorder (AUD) symptoms] among women during mid-life in the United States and to determine if there were pronounced cohort effects influencing these relationships. DESIGN: This was a retrospective cohort, longitudinal study. SETTING, PARTICIPANTS AND MEASUREMENTS: Data were drawn from the Monitoring the Future survey, an annual ongoing survey of high school students' substance use behaviors in the United States. Participants were women who completed the age 35 survey between 1993 and 2019, corresponding to high school senior years 1976-2002 (n = 9988). Past 2-week binge drinking and past 5-year AUD symptoms were self-reported. Age of first parenting was self-reported. FINDINGS: Binge drinking and AUD symptoms were higher among women in recent than in older cohorts. Women from the 2018-19 cohort had increased odds of binge drinking [odds ratio (OR) = 1.73, 95% confidence interval (CI) = 1.41-2.12] and AUD symptoms (OR = 1.51, CI = 1.27-1.80) relative to women from the 1993-97 cohort. Throughout cohorts, there was an inverse association between transition to parenthood and excessive drinking outcomes (e.g. range for ORs for binge drinking among those without children compared with those who had had children between the ages of 18 and 24: 1.22-1.55). Simultaneously, there was a population shift towards delaying parenting in recent cohorts (i.e. 54% of women in the 1993-97 cohort had children before age 30 compared with 39% in the two recent cohorts), increasing the size of the group at highest risk for excessive drinking. CONCLUSIONS: In the United States, subgroups of women at highest risk of excessive drinking appear to be expanding, probably supported in part by a trend towards delayed parenting.

Trends in alcohol-related liver disease mortality in Australia: An age-period-cohort perspective.

BACKGROUND AND AIMS: There have been few systematic attempts to examine how alcohol-related mortality has changed in Australia, and no studies that have explored cohort effects in alcohol-related mortality. This study uses more than 50 years of data to measure age, period and cohort trends in alcohol-related liver disease (ALD) mortality. DESIGN, SETTING AND CASES: This was a retrospective age-period-cohort analysis of total Australian ALD mortality data from 1968 to 2020 in Australia. There was a total of 35 822 deaths-27 208 men (76%) and 8614 women (24%). MEASUREMENTS: Deaths from ALD were grouped into 5-year age groups and periods (e.g. deaths for 20-24-year-olds between 1968 and 1972 were combined). FINDINGS: ALD mortality peaked in the late 1970s and early 1980s for both men and women. In age-period-cohort models, mortality was highest for cohorts born 1915-30. For example, men born between 1923 and 1927 had a relative risk of 1.58 [95% confidence interval (CI) = 1.52, 1.64] compared with men born between 1948 and 1952. For women, there was an increase in risk for cohorts born in the 1960s [e.g. the 1963-67 cohort had a relative risk (RR) of 1.16 (95% CI = 1.07, 1.25) compared with women born in 1948-52]. For men, there was a broad decline in mortality over time [e.g. in 2020, the RR was 0.87 (95% CI = 0.82, 0.92) compared with the reference year of 2000]. For women, mortality declined until 2000 and has been stable since. CONCLUSIONS: Alcohol-related liver disease mortality has declined across the Australian population since the 1970s and 1980s partly due to cohort-specific shifts as the highest-risk birth cohorts age. For women, this decline had stalled by the year 2000, and cohorts of women born during the 1960s were at higher risk than earlier cohorts, suggesting the need for thoughtful interventions as this population enters its highest-risk years for ALD mortality.

Global, region and national trends and age-period-cohort effects in colorectal cancer burden from 1990 to 2019, with predictions to 2039.

Nowadays, colorectal cancer (CRC) is the second leading cause of cancer deaths and contributes to a gradually increasing disease burden. We aimed to estimate the secular trends of global CRC burden, the effect of age, period, and birth cohort, and project the global burden over time. Based on the epidemiological CRC data from 1990 to 2019 in 204 countries and territories from GBD 2019, the estimated annual percentage change (EAPC), was calculated from a linear model and joinpoint regression model. We utilized an age-period-cohort model to reckon age, period, and birth cohort effects on CRC age-standardized rate. The burden of CRC was projected by conducting the BAPC model. Globally, there was a slight decline in the age-standardized DALY rate, which was more apparent in females, with high SDI regions and in Australia and Western Europe areas. Meanwhile, our model predicts a weaker increase in morbidity (EAPC of 0.37) and a speedier reduction in mortality (EAPC of -0.66) by the next 20 years. The relative risk of period for high SDI regions decreased from 1.08 (95%UI: 1.06-1.1) in 1990-1994 to 0.85 (95%UI:0.83-0.88) in 2015-2019, but worsens in low and middle SDI regions. The local drifts were more than 1 in the 30-34 and 35-39 age groups, indicating the rising tide of early-onset CRC. Given the gender and region-specific CRC, targeted efforts to reduce the prevalence of risk factors, improve screening coverage rates, and strengthen foundational medical facilities are necessary.

Age, period and cohort effects on time trends in monthly cannabis use in adult population: 1996-2019.

INTRODUCTION: With changes in norms related to cannabis use and in the regulation of cannabis, understanding trends in cannabis use is important, especially differentiating between trends that affect cohorts of all ages similarly, versus trends that disproportionately affect a younger generation. The present study examined the age-period-cohort (APC) effects on monthly cannabis use among adults in Ontario, Canada over a 24-year period. METHODS: Data were utilised from the Centre for Addiction and Mental Health Monitor Survey, an annual repeated cross-sectional survey of adults 18 years of age and older. The present analyses focused on the 1996 to 2019 surveys, which employed a regionally stratified sampling design using computer-assisted telephone interviews (N = 60,171). Monthly use of cannabis stratified by sex were examined. RESULTS: There was about a five-fold increase in monthly cannabis use from 1996 (3.1%) to 2019 (16.6%). The youngest adults use cannabis monthly more, but the patterns of monthly cannabis use appeared to be increasing among older adults. Adults born in the 1950s had higher prevalence of cannabis use (1.25 times more likely to use) compared to those born in 1964, with strongest period effect in 2019. The subgroup analysis of monthly cannabis use by sex showed little variation in APC effects. DISCUSSION AND CONCLUSIONS: There is a change in patterns of cannabis use among older adults and inclusion of birth cohort dimension improves the explanation of cannabis use trends. Adults in the 1950s birth cohort and increases in the normalisation of cannabis use could also be the key to explaining increasing monthly cannabis use.