The Impact of the Gut Microbiome, Environment, and Diet in Early-Onset Colorectal Cancer Development.

Traditionally considered a disease common in the older population, colorectal cancer is increasing in incidence among younger demographics. Evidence suggests that populational- and generational-level shifts in the composition of the human gut microbiome may be tied to the recent trends in gastrointestinal carcinogenesis. This review provides an overview of current research and putative mechanisms behind the rising incidence of colorectal cancer in the younger population, with insight into future interventions that may prevent or reverse the rate of early-onset colorectal carcinoma.

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.

DC/TMD axis I subtyping: generational and gender variations among East Asian TMD patients.

OBJECTIVES: This study examined the generational-gender distinctions in Diagnostic Criteria for Temporomandibular disorders (DC/TMD) subtypes among East Asian patients. METHODS: Consecutive "first-visit" TMD patients presenting at two university-based TMD/orofacial pain clinics in China and South Korea were enlisted. Demographic information along with symptom history was gathered and clinical examinations were performed according to the DC/TMD methodology. Axis I physical diagnoses were rendered with the DC/TMD algorithms and categorized into painful and non-painful TMDs. Patients were categorized into three birth cohorts, specifically Gen X, Y, and Z (born 1965-1980, 1981-1999, and 2000-2012 respectively) and the two genders. Data were evaluated using Chi-square/Kruskal-Wallis plus post-hoc tests and logistic regression analyses (α = 0.05). RESULTS: Gen X, Y, and Z formed 17.2%, 62.1%, and 20.7% of the 1717 eligible patients examined (mean age 29.7 ± 10.6 years; 75.7% women). Significant differences in prevalences of arthralgia, myalgia, headache (Gen X ≥ Y > Z), and disc displacements (Gen Z > Y > X) were observed among the three generations. Gen Z had substantially fewer pain-related and more intra-articular conditions than the other generations. Women presented a significantly greater frequency of degenerative joint disease and number of intra-articular conditions than men. After controlling for generation-gender interactions, multivariate analyses showed that "being Gen X" and female increased the risk of painful TMDs (OR = 2.20) and reduced the odds of non-painful TMDs (OR = 0.46). CONCLUSIONS: Generational-gender diversities in DC/TMD subtypes exist and are important for guiding TMD care and future research endeavors.

Trends and future projections of liver cancer incidence in Hong Kong: a population-based study.

BACKGROUND: Liver cancer remains a significant burden in Hong Kong. We sought to examine trends in liver cancer incidence using 30 years of cancer registry data in Hong Kong. Additionally, we aimed to assess the impact of age, period and birth cohort on liver cancer incidence, provided projections for liver cancer incidence until 2030, and examined the drivers of liver cancer incidence. METHODS: Data on liver cancer incidence were collected from the Hong Kong Cancer Registry (HKCaR). We assessed age, period, and birth cohort effects using age-period-cohort (APC) models. We employed Bayesian APC analysis with integrated nested Laplace approximations to project the future burden of liver cancer in Hong Kong. Furthermore, we attributed the changes in new liver cancer cases to population growth, population ageing, and epidemiological changes. RESULTS: The study included a total of 51,333 individuals, of whom 39,287 (76.53%) were male. From 1991 to 2020, the age-standardized liver cancer incidence rate in Hong Kong continued declining, while the number of new cases increased significantly, especially among males. The net drift, representing the overall annual percentage change of the age-adjusted rate, was - 3.06% (95% confidence interval [CI]: -3.31% to -2.80%) for males and - 3.85% (95% CI: -4.61% to -3.09%) for females. Local drift, which estimates the annual percentage change over time specific to age group, decreased in all age groups for both sexes, with a more pronounced decrease in younger age groups. The period and cohort risk of developing liver cancer also showed decreasing trends for both sexes. The study projected a decline in liver cancer cases for males but an increase for females in Hong Kong, with an estimated 1,083 cases in males and 710 cases in females by 2030. Demographic decomposition analysis revealed that while population growth and ageing were the main drivers of increased liver cancer cases, epidemiologic shifts mostly offset these factors. CONCLUSION: The period and cohort risk of developing liver cancer in Hong Kong declined due to epidemiological changes. Although the age-standardized incidence rates of liver cancer have also declined, demographic and epidemiological factors have led to lower case expectations in males but a likely increase in females. Further research and epidemiological assessment of the disease are needed.

Changing patterns of nasopharyngeal carcinoma incidence in Hong Kong: a 30-year analysis and future projections.

BACKGROUND: This study aims to evaluate the relationship between age, period, and birth cohort with the incidence trends of Nasopharyngeal Carcinoma (NPC) in Hong Kong, make projections through 2030 and parse the drivers of the incidence. METHODS: Using data from the Hong Kong Cancer Registry, we used an age-period-cohort model to uniquely estimate age, period, and cohort effects on NPC incidence trends and make projections. We further assessed the drivers of NPC incidence using a validated decomposition algorithm. RESULTS: From 1991 to 2020, crude and age-standardized incidence rates of NPC decreased significantly. The net drifts showed significant downward trends for both sexes, and local drift declined in all age groups. Period and cohort rate ratios revealed monotonic declining patterns for both sexes. Projections suggested that NPC incidence will continue to decline. Population decomposition showed that while population growth and ageing have led to an increase in NPC cases, epidemiologic changes offset these increases, resulting in an encouraging downward trend in the incidence and new NPC cases in Hong Kong. CONCLUSIONS: The period and cohort risk of NPC in Hong Kong decreased, and epidemiologic changes offset the contribution of demographic factors, resulting in a continued decline in NPC incidence and cases.

The epidemic of acute lymphoid leukemia in China: current trends and future prediction.

Background: China has experienced one of the fastest increases in the incidence of acute lymphoid leukemia (ALL). The aim of this study was to assess the long-term trends of the incidence and mortality of ALL in mainland China between 1990 and 2019 and to project these trends through 2028. Methods: Data on ALL were extracted from the Global Burden of Disease Study 2019; population data were extracted from World Population Prospects 2019. An age-period-cohort framework was used in the analysis. Results: The net drift for the incidence of ALL was 7.5% (95% confidence interval [CI]: 7.1%, 7.8%) per year in women and 7.1% (95% CI: 6.7%, 7.6%) in men, and local drift was found to be higher than 0 in every studied age group (p<0.05). The net drift for mortality was 1.2% (95% CI: 1.0%, 1.5%) in women and 2.0% (95% CI: 1.7%, 2.3%) in men. Local drift was lower than 0 in boys aged 0-4 years and girls aged 0-9 years and higher than 0 in men aged 10-84 years and women aged 15-84 years. The estimated period relative risks (RRs) for both incidence and mortality showed increasing trends in the recent period. The cohort RRs for incidence showed increasing trends in both sexes; however, the cohort RR for mortality was decreased in the recent birth cohort (women born after 1988-1992 and men born after 2003-2007). Compared with that in 2019, the incidence of ALL in 2028 is projected to increase by 64.1% in men and 75.0% in women, and the mortality is predicted to decrease by 11.1% in men and 14.3% in women. The proportion of older adult/adults individuals with incident ALL and ALL-related death was projected to increase. Conclusions: Over the last three decades, the incidence and mortality rates of ALL have generally increased. It is projected that the incidence rate of ALL in mainland China will continue to increase in the future, but the associated mortality rate will decline. The proportion of older adult/adults individuals with incident ALL and ALL-related death was projected to increase gradually among both sexes. More efforts are needed, especially for older adult/adults individuals.

Comparison of painful temporomandibular disorders, psychological characteristics, sleep quality, and oral health-related quality of life of patients seeking care before and during the Covid-19 pandemic.

BACKGROUND: Literature concerning Temporomandibular disorders (TMDs) and the Covid-19 pandemic is limited and disparate findings related to TMD frequencies, psychological distress, and quality of life were presented. This study investigated the prevalence of painful Temporomandibular disorders (TMDs) and compared the psychological, sleep, and oral health-related quality of life profiles of patients seeking TMD care before and during the Covid-19 pandemic. METHODS: Data were accrued from consecutive adult patients 12 months before (BC; control) and during (DC; case group) the Covid-19 pandemic. The Diagnostic Criteria for TMDs (DC/TMD), Depression, Anxiety, Stress Scales (DASS)-21, Pittsburgh Sleep Quality Index (PSQI), and Oral Health Impact Profile (OHIP)-TMDs were utilized and statistical analysis was performed using Chi-square/non-parametric tests (α = 0.05). RESULTS: The prevalence of painful TMDs was 50.8% before and 46.3% during the pandemic. Significant differences in PSQI and OHIP component scores were discerned between the BC and DC groups contingent on TMD pain. Total-DASS was moderately correlated to total-PSQI/OHIP (rs = 0.41-0.63). CONCLUSION: The covid-19 pandemic did not appear to exacerbate psychological distress but affected sleep and increased unease over TMD dysfunction.

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.

Female Homicides in Brazil and Its Major Regions (1980-2019): An Analysis of Age, Period, and Cohort Effects.

The objective was to analyze the temporal effects of age, period, and cohort on mortality from all female homicides, and from female homicides and by firearms, in Brazil from 1980 to 2019. Data were accessed from Brazilian health records. There was an increase in the risk of death in the 2000s in the North and Northeast regions and a decrease in the Southeast, South, and Midwest. Younger women had a higher risk of death than women born between 1950 and 1954. The findings may be correlated with the inefficiency of the Brazilian state in protecting female victims of violence.

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.

Risk of gastric carcinoma will be low in generations born at turn of the 20th and 21st centuries in Finland. Modelling NORDCAN data of the age group specific incidence rates of gastric cancer with PLS-regression and with attention to age ('age effect') and year of the birth ('cohort effect').

BACKGROUND AND METHODS: We examined in NORDCAN database how the annual age group-specific incidence rates (IR) of gastric cancer (GCA), and correspondingly the GCA risk, have declined in Finland during the twentieth century, and whether this decline corresponds to a decrease in the cohort-specific prevalence rate of Helicobacter pylori (Hp) gastritis that is considered an important precancerous risk condition for GCA. RESULTS: In modelling with partial least squares regression (PLSR), the logarithmically transformed IRs (ln(IR) of GCA were well explained with age and birth cohort as explanatory model variables. By considering the observed (actual) and the PLSR-modelled IRs, the IR of GCA (and the risk of GCA) has decreased gradually in Finland from 1900 onward, cohort by cohort. By prediction of the future with PLSR, the IRs of GCA will be markedly lower in all cohorts during the twenty-first century than in the twentieth century. By PLSR modelling, less than 10 GCA cases per 100,000 people are predicted to appear annually in cohorts (generations) born at the turn of the 20th and 21st centuries, even when these people will be 60-80 years old in the years 2060-2070. CONCLUSIONS: The IR of GCA and GCA risk progressively declined by cohort in Finland during the whole twentieth century. This decline corresponds in extent and time window to earlier observations in the decline of the prevalence rate of Hp gastritis in the same birth cohorts and supports the hypothesis of the role of Hp gastritis as an important risk condition of GCA.

Trends and projections of ovarian cancer incidence in Hong Kong: A population-based study.

INTRODUCTION: This study analyzed the incidence of ovarian cancer in Hong Kong and its association with age, calendar period and birth cohort, made projections through 2030, and attributed differences in new cancer cases to demographic and epidemiologic changes. MATERIAL AND METHODS: Incidence data for ovarian cancer were obtained from the Hong Kong Cancer Registry. We employed the age-period-cohort modeling approach to investigate the association between ovarian cancer incidence and age in Hong Kong women, with particular emphasis on examining the changing trends of period and cohort effects on incidence. We projected the incidence of ovarian cancer in Hong Kong between 2018 and 2030 and attributed the rise in new cancer cases to epidemiologic and demographic shifts. RESULTS: Between 1990 and 2017, a total of 11 182 women were diagnosed with ovarian cancer in Hong Kong. Crude and age-standardized rates increased from 8.2 and 7.8 per 100 000 person-years to 16.3 and 11.5 per 100 000 person-years, respectively. New cases of ovarian cancer rose from 225 in 1990 to 645 in 2017. We observed an increased risk of ovarian cancer throughout the study period and in the post-1940 birth cohort. The projected incidence rate and new cases of ovarian cancer are expected to continue growing due to demographic and epidemiologic changes such as fertility patterns and lifestyle factors, with an estimated 981 cases in 2030. CONCLUSIONS: The period risk and cohort risk of ovarian cancer among Hong Kong women is increasing. Demographic and epidemiologic changes may continue to increase ovarian cancer incidence and new cases in Hong Kong.

Birth cohort effects in incident renal replacement therapy in Japan, 1982-2021.

BACKGROUND: This study aimed to investigate the long-term trends of incident end-stage kidney disease (ESKD) requiring renal replacement therapy (RRT) in Japan using age-period-cohort analysis and evaluated birth cohort effects for incident ESKD requiring RRT. METHODS: The number of incident RRT patients aged between 20 and 84 years by sex from 1982 to 2021 was extracted from the Japanese Society of Dialysis Therapy registry data. Annual incidence rates of RRT were calculated using census population as denominators, and changes in the incidence rates were evaluated using an age-period-cohort model. The age and survey year period categories generated 20 birth cohorts with 5-year intervals (from 1902-1907 to 1997-2001). RESULTS: The incidence rates of RRT in both sexes initially rose in the birth cohorts born in the early 1900s, and then decelerated and peaked during 1940-1960s in men and 1930-1940s in women, following a steady decline in both sexes. Compared with the reference 1947-1951 birth cohort, the highest cohort rate ratio was 1.14 (95% CI, 1.04-1.25) in the 1967-1971 birth cohort in men and 1.04 (95% CI, 0.98-1.10) in the 1937-1941 birth cohort in women. CONCLUSIONS: Significant cohort effects were identified in both sexes, but the peak of RRT was different for each sex. Our findings suggest that men born between 1940 and 1960s and women born between 1930 and 40 s may be important target populations to consider when decreasing incidence rates of RRT among the general Japanese population.

Early-onset colorectal cancer: A review of current knowledge.

Colorectal cancer (CRC) is one of the most prevalent malignancies worldwide. Although most prevalent among older people, its incidence above 50 years old has been decreasing globally in the last decades, probably as a result of better screening. Paradoxically, its incidence in patients below 50 years old [early-onset CRC (EO-CRC)] has been increasing, for reasons not yet fully understood. EO-CRC's increasing incidence is genre independent but shows racial disparities and has been described to occur worldwide. It follows a birth-cohort effect which probably reflects a change in exposure to CRC risk factors. Its incidence is predicted to double until 2030, which makes EO-CRC a serious public health issue. Both modifiable and non-modifiable risk factors have been identified - some are potential targets for preventive measures. EO-CRC is often diagnosed at advanced stages and histological features associated with poor prognosis have been described. EO-CRC presents some distinctive features: Microsatellite in-stability is common, but another subtype of tumours, both microsatellite and chromosome stable also seems relevant. There are no age-specific treatment protocols and studies on EO-CRC survival rates have shown conflicting data. Due to the higher germline pathological mutations found in EO-CRC patients, an accurate genetic risk evaluation should be performed. In this review, we summarize the current evidence on epidemiological, clinical, histopathological and molecular features of EO-CRC and discuss the contribution of genetics and lifestyle risk factors. We further comment on screening strategies and specific dimensions to consider when dealing with a younger cancer patient.

[Epidemiological consideration for death causes among Japanese: focused on age, time, and birth cohort effects].

This study aimed to clarify the death causes among Japanese. National vital statistics data from 1995 to 2020 were analyzed using the mean polish process. The results showed that deaths from cancer increased after middle age, and deaths from heart disease, pneumonia, and cerebrovascular disease increased after later life (age effect). Recently, mortality from cerebrovascular disease, heart disease, and pneumonia is decreasing (time effect). More individuals in the birth cohort born after 1906 died from cancer compared to that of earlier generations who mainly died from heart disease, pneumonia, and cerebrovascular disease (birth cohort effect). The time effect is more modifiable and/or depending on social conditions and interventions compared to that of the age effect. In Japan, if lifestyle-related diseases that are risk factors for cerebrovascular and heart diseases, such as hypertension, are further prevented or treated, mortality from such diseases will decrease consequently.

Declining Comprehensiveness of Services Delivered by Canadian Family Physicians Is Not Driven by Early-Career Physicians.

We describe changes in the comprehensiveness of services delivered by family physicians in 4 Canadian provinces (British Columbia, Manitoba, Ontario, Nova Scotia) during the periods 1999-2000 and 2017-2018 and explore if changes differ by years in practice. We measured comprehensiveness using province-wide billing data across 7 settings (home, long-term care, emergency department, hospital, obstetrics, surgical assistance, anesthesiology) and 7 service areas (pre/postnatal care, Papanicolaou [Pap] testing, mental health, substance use, cancer care, minor surgery, palliative home visits). Comprehensiveness declined in all provinces, with greater changes in number of service settings than service areas. Decreases were no greater among new-to-practice physicians.

Incidence trends of oral cavity, oropharyngeal, hypopharyngeal and laryngeal cancers among males in Taiwan, 1980-2019: a population-based cancer registry study.

In a country with a high prevalence of cigarette smoking, betel chewing, and alcohol drinking, cancers of the oral cavity, nasopharynx, and larynx were the fourth, twelfth and seventeenth leading causes of cancer death, respectively, for men in 2020. We analyzed patients with head and neck cancer from 1980 to 2019 from the Taiwan Cancer Registration Database and discussed the annual average percent change, average percent change, age period, and birth cohort. Obvious period effects and birth effects are seen in oral, oropharyngeal, and hypopharyngeal cancer; however, the most significant period effect was seen between 1990 and 2009, which mainly reflects the consumption of betel nuts per capita. In addition, the period effect lessens after 2010 in oral cancer and hypopharyngeal cancers, while oropharyngeal cancers remain an obvious period effect, which results from the rising prevalence of HPV. Due to the high prevalence rate of betel quid chewing and cigarette smoking in the 1990s, the government executed several acts. As a result, the age-adjusted incidence rates of oral, oropharyngeal, and hypopharyngeal cancers have flattened since 2010, which can be explained by the declining cigarette smoking rate. The strict policy indeed shows an obvious effect on the head and neck cancer incidence rates, and we expect to see a further decline in the future.

Urban-Rural Disparity in Birth Cohort Effects on Breast Cancer Incidence.

Breast cancer is the most commonly diagnosed cancer among women worldwide. Studies have reported minimal birth cohort effects on the incidence rates of breast cancer in Western countries but have reported notable birth cohort effects in some Asian countries. The risks of breast cancer may also vary within a country. In the present study, we abstracted female invasive breast cancer data from the Taiwan Cancer Registry for the period 1997-2016. We used the age-period-cohort model to compare birth cohort effects on breast cancer incidence rates between urban and rural regions in Taiwan. We identified a notable urban-rural disparity in birth cohort effects on breast cancer incidence rates in women in Taiwan. The incidence rates in the urban regions were higher than those in the rural regions across all cohorts. However, the incidence rates rose faster in the rural regions than in the urban regions across the cohorts. The risks of breast cancer observed for women born in 1992 were approximately 22 and 11 times than those observed for women born in 1917 in rural and urban regions, respectively. The observed gap in breast cancer incidence rates between the urban and rural regions gradually disappeared across the cohorts. Accordingly, we speculate that urbanization and westernization in Taiwan may be the drivers of female breast cancer incidence rates across birth cohorts.

Age, period and cohort effects in depression prevalence among Canadians 65+, 1994 to 2018: A multi-level analysis.

BACKGROUND: The nature of the Canadian population 65+ has changed considerably over the past several decades. They comprise a larger proportion of the population, are better educated, and are wealthier than previous generations. We estimate the contributions of chronological aging, temporal periods, and birth cohort effects on the trends in the major depressive episode (MDE) prevalence among Canadian seniors from 1994/1995 to 2017/2018. METHODS: Using data from two sets of national health surveys, the National Population Health Survey (NPHS) and the Canadian Community Health Survey (CCHS). Pooled data on 150,246 survey respondents aged 65+ from 16 repeated cross-sectional surveys are included. Hierarchical regression age-period-cohort models were used to visualize the linear and non-linear effects of age, period, and cohort trends in late-life depression. RESULTS: We found that: the prevalence of MDE in later life fluctuated non-significantly during the study time period; the probability of developing MDE declined with increasing age from 65 to 80+ (ß = -.32, p = .027). The significant quadratic birth cohort predictor showed a non-linear increasing association with the prevalence of MDE from the earlier to later-born cohorts (ß = .01, p = .049). We also found that females 65+ were consistently more likely to be depressed than males 65+ (ß = .47, p = .007). The significantly negative "age × female" interaction shows that age exerts a greater effect on females' probability of developing MDE than males (ß = -.09, p = .011). There were no consistent significant period effects but there were peaks in prevalence around 2001, 2008, and 2012 which corresponded to some recent historical events. Our moderation analysis documents that lower levels of education significantly contributed to the higher rates of depression among cohorts born earlier in the 20th century. CONCLUSIONS: Our findings show the presence of strong chronological age and cohort effects and weaker period effects on the prevalence of late-life depression in Canadian seniors.