Use of age-period-cohort analysis in cancer epidemiology research

Trends in uterine cancer incidence in the United States: The contribution of age, period and cohort effects

OBJECTIVE

In the U.S., uterine cancer incidence is rising, with racial and ethnic minorities experiencing the largest increases. We performed age-period-cohort analyses using novel methods to examine the contribution of age at diagnosis (age), year of diagnosis (period), and birth cohort (cohort), to trends in uterine cancer incidence.

METHODS

We used uterine cancer incidence data from the Surveillance, Epidemiology, and End Result (SEER) 12 database (1992-2019), and performed hysterectomy-correction. We generated hexamaps to visualize age, period, and cohort effects, and used mutual information to estimate the percent contribution of age, period, and cohort effects, individually and combined, on uterine cancer incidence, overall and by race and ethnicity and histology.

RESULTS

Hexamaps showed an increase in uterine cancer in later time periods, and a cohort effect around 1933 showing a lower incidence compared with earlier and later cohorts. Age, period, and cohort effects combined contributed 86.6% (95% CI: 86.4%, 86.9%) to the incidence. Age effects had the greatest contribution (65.1%, 95% CI: 64.3%, 65.9), followed by cohort (20.7%, 95% CI: 20.1%, 21.3%) and period (14.2%, 95% CI: 13.7%, 14.8%) effects. Hexamaps showed higher incidence in recent years for non-Hispanic Blacks and non-endometrioid tumors.

CONCLUSIONS

Age effects had the largest contribution to uterine cancer incidence, followed by cohort and period effects overall and across racial and ethnic groups and histologies.

IMPACT

These findings can inform uterine cancer modeling studies on the effects of interventions that target risk factors which may vary across age, period, or cohort.

Investigating temporal patterns of colorectal cancer incidence in Spain: a comprehensive analysis of age, period and cohort effects, 1990-2019

AIM

This study aimed to evaluate how age, period, and cohort (A-P-C) impact colorectal cancer (CRC) incidence in Spain from 1990 to 2019.

METHOD

Using data from the Global Burden of Disease Study 2019, we used joinpoint analysis to identify long-term trends and A-P-C modelling to quantify net drift, local drift, longitudinal age curves, and rate ratios (RRs) of period and cohort effects.

RESULTS

CRC incidence increased steadily in Spain from 1990 to 2019, with a more significant rise in males than in females. The age standardized rates rose from 84.9 to 129.3 cases per 100,000 in males and from 56.9 to 70.3 cases per 100,000 in females. Joinpoint analysis revealed distinct patterns for men and women: male incidence showed three phases (a surge until 1995, a slowdown until 2012, and a subsequent decrease) while female incidence showed a single increase until 2011 and then stabilized. Local drifts increased in all age groups over 45, with stability in males under 45 and a decrease in females aged 30-39. The risk of CRC increased with age, with males consistently having a higher risk than females. The risk of CRC increased over time for both men and women but at different rates. The risk for cohorts born in the early to mid-20th century peaked in the 1960s and remained stable until the late 1990s.

CONCLUSION

The increasing incidence of CRC in Spain, with distinct patterns by gender and birth cohort, underlines the importance of preventive strategies adapted to temporal and demographic variations to address this public health challenge.

Trends in mortality due to tracheal, bronchial, and lung cancer across the BRICS: An age-period-cohort analysis based on the Global Burden of Disease Study 1990-2019

BACKGROUND

Tracheal, bronchus, and lung cancer (TBL) is a major cause of mortality and top contributor to productivity loss in large emerging economies such as the BRICS (Brazil, Russia, India, China, and South Africa). We examined the time trends of TBL mortality across the BRICS to better understand the disease burden in these countries and inform public health and healthcare resource allocation.

METHODS

TBL mortality-related data between 1990 and 2019 were obtained from the Global Burden of Disease Study 2019 and analyzed using age-period-cohort models. Net drift (local drift) was used to describe the expected age-adjusted TBL mortality rate over time overall (each age group); the longitudinal age curve was used to reflect the age effect; the period rate ratios (RRs) were used to reflect the period effect; and the cohort RR was used to reflect the cohort effect.

RESULTS

In 2019, there were 958.3 thousand TBL deaths across the BRICS, representing 46.9% of the global TBL deaths. From 1990 to 2019, the age-standardized mortality rate (ASMR) of TBL decreased in Russia, Brazil, and South Africa while increased in China and India, with the largest reduction reported in Russia (-29.6%) and the largest increase in China (+22.4%). India showed an overall increase (+15.7%) in TBL mortality but the mortality risk decreased among individuals born after 1990 (men) and 1995 (women). Although South Africa and Brazil experienced an overall decline in TBL mortality, their recent birth cohorts, such as Brazilian individuals born after 1985 (men) and 1980 (women), and South African men born after 1995, had an increasing TBL mortality risk. China has experienced an overall increase in TBL mortality, with the mortality risk rising among individuals born after 1995 for both men and women. Russia, which had the highest TBL mortality among the BRICS countries in 1990, has demonstrated significant improvement over the past three decades.

CONCLUSIONS

Over the past 30 years, the BRICS accounted for an increasing proportion of global TBL mortality. TBL mortality increased in older women in all the BRICS countries except Russia. Among the recent birth cohort, the risk of TBL mortality increased in Brazil, China, and South Africa. More effective efforts are needed in the BRICS to reduce the burden of TBL and help achieve the United Nation's Sustainable Development Goals.

Growing old and being old: Emotional well-being across adulthood

The present study examines change in reports of daily, weekly, and monthly psychological distress over 20 years, and of negative and positive affect over 10 years, using data from the Midlife in the United States study. The study includes three waves of data collection on adults ranging from 22 to 95 years old. Cross-sectional findings reveal that older age is related to lower levels of psychological distress and negative affect and to higher levels of positive affect across each successive age group. Yet, longitudinal findings vary across younger, middle-aged, and older adults. Psychological distress decreases over time among younger adults (although only until age 33 for weekly reports), remains stable in midlife, and is stable (monthly) or slightly increases (daily and weekly) among older adults. For negative affect, levels decrease over time for younger and middle-aged adults, and only increase for the oldest adults for daily and monthly affect. Positive affect is stable over time among younger adults, but decreases in midlife starting in the mid-fifties. In conclusion, overall patterns of findings suggest that being old (assessed cross-sectionally) is related to higher levels of emotional well-being. Growing old (assessed longitudinally) is related to improvements in emotional well-being across younger and early middle adulthood, which mirrors cross-sectional findings. There is relative stability in later midlife, however, and continued stability or slight declines across older age. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Temporal Pattern and Age-Period-Cohort Analysis of Breast Cancer Incidence in Iranian Women (2009-2017)

BACKGROUND

Breast cancer accounted for 28.1% of all female cancers in 2020 in Iran. This study was conducted to evaluate the time trend of breast cancer incidence and to identify the changes of breast cancer incidence in age, period, and birth cohorts in Iran, in the 2009-2017 timeframe.

METHODS

Annual cancer statistics for female breast cancer were obtained from the Iranian National Population-based Cancer Registry (INPCR) database from 2009 to 2017. The age-period-cohort (APC) analysis was used to evaluate the time trend of breast cancer incidence in age, period and birth cohorts between 2009 and 2017. R package (Epi) was used to analyze data. Results were considered statistically significant at P<0.05.

RESULTS

The age effect showed an increased incidence of breast cancer until the age of 45, and after this age the speed of increase was slower until 65 years. There was an increased diagnosis in 2015-2017 (period effect) for many age groups, especially in the 70- and over 80-year-old group.

CONCLUSION

Our findings indicated that breast cancer incidence peaks in the age of 45 in Iranian women, which is a decade earlier compared to the Western world. The period effect in 2015-2017 can be explained by the fact that in 2014, the former Iranian pathology-based cancer registry was upgraded to a population-based cancer registry, which resulted in improved coverage of cancer registry and case finding.

Is early-onset cancer an emerging global epidemic? Current evidence and future implications

Over the past several decades, the incidence of early-onset cancers, often defined as cancers diagnosed in adults <50 years of age, in the breast, colorectum, endometrium, oesophagus, extrahepatic bile duct, gallbladder, head and neck, kidney, liver, bone marrow, pancreas, prostate, stomach and thyroid has increased in multiple countries. Increased use of screening programmes has contributed to this phenomenon to a certain extent, although a genuine increase in the incidence of early-onset forms of several cancer types also seems to have emerged. Evidence suggests an aetiological role of risk factor exposures in early life and young adulthood. Since the mid-20th century, substantial multigenerational changes in the exposome have occurred (including changes in diet, lifestyle, obesity, environment and the microbiome, all of which might interact with genomic and/or genetic susceptibilities). However, the effects of individual exposures remain largely unknown. To study early-life exposures and their implications for multiple cancer types will require prospective cohort studies with dedicated biobanking and data collection technologies. Raising awareness among both the public and health-care professionals will also be critical. In this Review, we describe changes in the incidence of early-onset cancers globally and suggest measures that are likely to reduce the burden of cancers and other chronic non-communicable diseases.

Is the Millennial Generation Left Behind? Inter-Cohort Labour Income Inequality in a Context of Economic Shock

This paper provides new evidence on how intergenerational income inequality evolves during the period 2005-2019. Using the Continuous Sample of Working Histories (CSWH), which includes administrative data about working lives and personal characteristics of Spanish workers, we shed light on the effect of the Great Recession on income inequality between cohorts in Spain. As a proxy of income, we employ monthly earnings data, provided by the CSWH. From a life course approach, we use two age-period-cohort (APC) models which allow us to separately identify three components: cohort, age and period effects. First, we examine relative earnings which will reveal whether there are income differences between generations. Second, we measure how absolute earnings have developed over time. Our results suggest that some generations are more disadvantaged in terms of income by their year of birth than others. Likewise, the evidence points out that the economic context experienced by a generation in their transition to the labour market is a key factor in the development of their income.

A systematic review of methods to estimate colorectal cancer incidence using population-based cancer registries

Background

Epidemiological studies of incidence play an essential role in quantifying disease burden, resource planning, and informing public health policies. A variety of measures for estimating cancer incidence have been used. Appropriate reporting of incidence calculations is essential to enable clear interpretation. This review uses colorectal cancer (CRC) as an exemplar to summarize and describe variation in commonly employed incidence measures and evaluate the quality of reporting incidence methods.

Methods

We searched four databases for CRC incidence studies published between January 2010 and May 2020. Two independent reviewers screened all titles and abstracts. Eligible studies were population-based cancer registry studies evaluating CRC incidence. We extracted data on study characteristics and author-defined criteria for assessing the quality of reporting incidence. We used descriptive statistics to summarize the information.

Results

This review retrieved 165 relevant articles. The age-standardized incidence rate (ASR) (80%) was the most commonly reported incidence measure, and the 2000 U.S. standard population the most commonly used reference population (39%). Slightly more than half (54%) of the studies reported CRC incidence stratified by anatomical site. The quality of reporting incidence methods was suboptimal. Of all included studies: 45 (27%) failed to report the classification system used to define CRC; 63 (38%) did not report CRC codes; and only 20 (12%) documented excluding certain CRC cases from the numerator. Concerning the denominator estimation: 61% of studies failed to state the source of population data; 24 (15%) indicated census years; 10 (6%) reported the method used to estimate yearly population counts; and only 5 (3%) explicitly explained the population size estimation procedure to calculate the overall average incidence rate. Thirty-three (20%) studies reported the confidence interval for incidence, and only 7 (4%) documented methods for dealing with missing data.

Conclusion

This review identified variations in incidence calculation and inadequate reporting of methods. We outlined recommendations to optimize incidence estimation and reporting practices. There is a need to establish clear guidelines for incidence reporting to facilitate assessment of the validity and interpretation of reported incidence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01632-7.

Assessment of Oral Human Papillomavirus Prevalence in Pediatric and Adult Patients within a Multi-Ethnic Clinic Population

Introduction: Human papillomavirus (HPV) encompasses a large family of oncogenic viruses responsible for increasing rates of both cervical and oral cancer, particularly among minority and low-income populations. Although this represents an increasingly significant public health risk, few studies have screened for oral HPV within Nevada. Based upon this information, the primary objective of this study was to provide a temporal analysis of oral HPV screening among a primarily low-income, minority patient population. Methods: This retrospective analysis was reviewed and approved by the Institutional Review Board (IRB). In brief, unstimulated saliva samples were previously obtained from clinical patient volunteers who provided informed consent and pediatric assent (if applicable). DNA was isolated and screened using spectrophotometry for quality (A260:A280 ratio > 1.70) and quantity (concentration > 100 ng). Validated qPCR primers were used to screen repository samples for high-risk HPV strains HPV16 and HPV18. Results: A total of N = 930 samples were identified for this study, which involved n = 555 samples from adults and n = 375 from pediatric patients treated between 2011 and 2019. A demographic analysis revealed nearly equal distribution between males and females with most derived from non-White (minority) patients. A qPCR screening revealed an overall increase in high-risk HPV of 3.17-fold from 5.7% in 2011 to 18.1% in 2019 and a coefficient of determination or R2 = 0.764, suggesting a strong, positive correlation between more recent sample years and HPV-positive results, which was observed among both pediatric (R2 = 0.671) and adult (R2 = 0.971) patients. In addition, although the average age among adult patients increased over time, a significant decrease was observed among pediatric patients from an average of 16.0 years to 14.81 years. Conclusions: These data suggest temporal changes and positive increases in the prevalence of oral HPV among both the pediatric and adult patient samples taken from this clinic population. These data are important as considerations are made regarding which HPV vaccination education and awareness programs are introduced and the specific populations most likely to benefit from these interventions.

Trends and projections in the incidence of oesophageal cancer in the Netherlands: An age-period-cohort analysis from 1989 to 2041

In Western populations, the incidence of oesophageal squamous cell carcinoma (OSCC) has been declining, whereas the incidence of oesophageal adenocarcinoma (OAC) has been increasing. Our study examines temporal trends in the incidence of oesophageal cancer in the Netherlands between 1989 and 2016, in addition to predicting future trends through 2041. Data from the Netherlands Cancer Registry and Statistics Netherlands were collected to obtain incidence trends of OSCC and OAC for the period 1989 to 2016. Age‐period‐cohort (APC) modelling was used to estimate the contribution of age, calendar period and birth cohort on the observed incidence trends. To predict the future numbers of new cases of both OSCC and OAC from 2017 to 2041, log‐linear APC models were fitted to the trends of 1989 to 2016. The age‐standardised incidence rates of OSCC have decreased slightly for men and increased slightly for women. In contrast, a marked increase in the incidence of OAC was observed, ranging from 2.8 per 100 000 persons in 1989 to 10.1 in 2016. This increase in OAC incidence was more prominent in men, and it will result in an increased risk of OAC for successive generations. Future projections indicate that the incidence of OAC will further increase to 13.1 per 100 000 persons in 2037 to 2041, meaning that there will be 13 259 cases of OAC in 2037 to 2041, as compared to 9386 diagnoses in 2017 to 2021. The changing epidemiologic trends in oesophageal cancer in the Netherlands should be reflected in the development of prevention, early detection and treatment strategies.

What's new?

The incidence of esophageal adenocarcinoma (OAC) is on the rise in Western countries. Better understanding of this trend could facilitate critical improvements in OAC prevention, early detection, and treatment strategies. Here, the authors investigated trends in OAC incidence from 1989 to 2016 for successive birth cohorts in the Netherlands. OAC incidence was found to have increased significantly since 1989, with risk rising most noticeably in men. Analyses through 2037‐2041 predict continued growth in OAC cases. The findings highlight the importance of promoting measures to prevent esophageal cancer, particularly those aimed at controlling modifiable risk factors, such as obesity and smoking.

Surveillance of the Incidence and Mortality of Oral and Pharyngeal, Esophageal, and Lung Cancer in Nevada: Potential Implications of the Nevada Indoor Clean Air Act

Reviews of national and state-specific cancer registries have revealed differences in rates of oral, esophageal, and lung cancer incidence and mortality that have implications for public health research and policy. Many significant associations between these types of cancers and major risk factors, such as cigarette usage, may be influenced by public health policy such as smoking restrictions and bans-including the Nevada Clean Indoor Air Act (NCIAA) of 2006 (and subsequent modification in 2011). Although evaluation of general and regional advances in public policy have been previously evaluated, no recent studies have focused specifically on the changes to the epidemiology of oral and pharyngeal, esophageal, and lung cancer incidence and mortality in Nevada. Methods: Cancer incidence and mortality rate data were obtained from the National Cancer Institute (NCI) Division of Cancer Control and Population Sciences (DCCPS) Surveillance, Epidemiology and End Results (SEER) program. Most recently available rate changes in cancer incidence and mortality for Nevada included the years 2012-2016 and are age-adjusted to the year 2000 standard US population. This analysis revealed that the overall rates of incidence and mortality from these types of cancer in Nevada differs from that observed in the overall US population. For example, although the incidence rate of oral cancer is decreasing in the US overall (0.9%), it is stable in Nevada (0.0%). However, the incidence and mortality rates from esophageal cancer are also decreasing in the US (-1.1%, -1.2%, respectively), and are declining more rapidly in Nevada (-1.5%, -1.9%, respectively). Similarly, the incidence and mortality rates from lung are cancer are declining in the US (-2.5%, -2.4%, respectively) and are also declining more rapidly in Nevada (-3.2%, -3.1%, respectively). Analysis of previous epidemiologic data from Nevada (1999-2003) revealed the highest annual percent change (APC) in oral cancer incidence in the US was observed in Nevada (+4.6%), which corresponded with the highest APC in oral cancer mortality (+4.6%). Subsequent studies regarding reduced rates of cigarette use due to smoking restrictions and bans have suggested that follow up studies may reveal changes in the incidence and mortality rates of oral and other related cancers. This study analysis revealed that oral cancer incidence rates are no longer increasing in Nevada and that mortality rates have started to decline, although not as rapidly as the overall national rates. However, rapid decreases in both the incidence and mortality from esophageal and lung cancer were observed in Nevada, which strongly suggest the corresponding changes in oral cancer may be part of a larger epidemiologic shift resulting from improved public health policies that include indoor smoking restrictions and bans.

Ensemble forecasting of a continuously decreasing trend in bladder cancer incidence in Taiwan

Bladder cancer is one of the most common malignancies involving the urinary system of about 1.65 million cases worldwide. To attain the 25 by 25 goal set by the World Health Organization (25% reduction in non-communicable diseases between 2015 and 2025), developing strategies to reduce cancer burdens is essential. The data of the study comprised the age-specific bladder cancer cases and total population numbers from age 25 to 85 and above from 1997 to 2016 in Taiwan. An ensemble age-period-cohort model was used to estimate bladder cancer incidence trends and forecast the trends to 2025. For men, the projected age-standardized incidence rates per 100,000 people in 2020 and 2025 are 13.0 and 10.4, respectively, with a 16.1% and 32.9% decrease projected from 2016 to 2020 and 2025, respectively. For women, the projected age-standardized incidence rates per 100,000 people in 2020 and 2025 are 4.7 and 3.7, respectively, with a 16.1% and 33.9% decrease projected from 2016 to 2020 and 2025, respectively. The age-specific bladder cancer incidence rates demonstrated a consistently downward trend after 2003 for all ages and both sexes. This study projects that the incidence rates of bladder cancer in Taiwan will continue to decrease, and more than a 25% reduction can be achieved from 2016 to 2025.

The rise of metastatic bone disease in Ireland

To describe the expected rise of metastatic bone disease in Ireland, the relative primary types, and the locations of spread within the skeleton. This was a population-based epidemiological study using cancer registry data. We included patients with known metastatic cancer to bone, within 1 year of the primary diagnosis, during the years 1994 to 2012 inclusive. Our main outcome measures were age-specific, gender-specific and age-standardised incidence rates of bone metastasis, primary types and metastatic location within the skeleton. There were 14,495 recognised cases of bone metastasis in Ireland, 1994-2012 inclusive. Cases consistently rose over the time period, with 108% case increase and 51% age-standardised incidence rise. Annual percentage change increased across both genders and over all age groups. Most of this rise was not due to demographic population change. Breast, prostate and lung accounted for the majority of primary types. GI cancers were the fourth most common primary type. There were proportional increases in breast and lung, with proportional decreases in prostate. The spine was the major metastatic site. Bone metastasis is a significant and rising healthcare concern in Ireland. This rise is disproportionate to demographic changes. Breast, prostate and lung cancers account for the majority. GI cancers are implicated in an unexpectedly high number of cases. Spine is the most common location of bony metastasis, especially at presentation. Prudent healthcare planning is necessitated to prepare for the growing consequences of bone metastasis in cancer patients.