Long-term trends of HIV/AIDS incidence in India: an application of joinpoint and age-period-cohort analyses: a gendered perspective

Background

Monitoring the transmission patterns of human immunodeficiency virus (HIV) in a population is fundamental for identifying the key population and designing prevention interventions. In the present study, we aimed to estimate the gender disparities in HIV incidence and the age, period, and cohort effects on the incidence of HIV in India for identifying the predictors that might have led to changes in the last three decades.

Data and methods

This study utilizes data from the Global Burden of Disease Study for the period 1990-2019. The joinpoint regression analysis was employed to identify the magnitude of the changes in age-standardized incidence rates (ASIRs) of HIV. The average annual percentage changes in the incidence were computed, and the age-period-cohort analysis was performed.

Results

A decreasing trend in the overall estimates of age-standardized HIV incidence rates were observed in the period 1990-2019. The joinpoint regression analysis showed that the age-standardized incidence significantly declined from its peak in 1997 to 2019 (38.0 and 27.6 among males and females per 100,000 in 1997 to 5.4 and 4.6, respectively, in 2019). The APC was estimated to be 2.12 among males and 1.24 among females for the period 1990-2019. In recent years, although the gender gap in HIV incidence has reduced, females were observed to bear a proportionately higher burden of HIV incidence. Age effect showed a decline in HIV incidence by 91.1 and 70.1% among males and females aged between 15-19 years and 75-79 years. During the entire period from 1990-1994 to 2015-2019, the RR of HIV incidence decreased by 36.2 and 33.7% among males and females, respectively.

Conclusion

India is experiencing a decline in new HIV infections in recent years. However, the decline is steeper for males than for females. Findings highlight the necessity of providing older women and young women at risk with effective HIV prevention. This study emphasizes the need for large-scale HIV primary prevention efforts for teenage girls and young women.

Long-Term Projections of Cancer Incidence and Mortality in Japan and Decomposition Analysis of Changes in Cancer Burden, 2020-2054: An Empirical Validation Approach

PURPOSE

The aim of this study was to project new cancer cases/deaths forward to 2054, and decompose changes in cancer cases/deaths to assess the impact of demographic transitions on cancer burden.

METHODS

We collected data on cancer cases/deaths up to 2019, empirically validated the projection performance of multiple statistical models, and selected optimal models by applying time series cross-validation.

RESULTS

We showed an increasing number of new cancer cases but decreasing number of cancer deaths in both genders, with a large burden attributed to population aging. We observed the increasing incidence rates in most cancer sites but reducing rates in some infection-associated cancers, including stomach and liver cancers. Colorectal and lung cancers were projected to remain as leading cancer burdens of both incidence and mortality in Japan over 2020-2054, while prostate and female breast cancers would be the leading incidence burdens among men and women, respectively.

CONCLUSIONS

Findings from decomposition analysis require more supportive interventions for reducing mortality and improving the quality of life of Japanese elders. We emphasize the important role of governments and policymakers in reforming policies for controlling cancer risk factors, including oncogenic infections. The rapid increase and continued presence of those cancer burdens associated with modifiable risk factors warrant greater efforts in cancer control programs, specifically in enhancing cancer screening and controlling cancer risk factors in Japan.

Trends and projections in cutaneous melanoma death in the Netherlands from 1950 to 2045

ABSTRACT

Child sun protection has recently been linked to the future disappearance of fatal melanoma in adults in successive generations. In the Netherlands, however, mortality rates from melanoma have increased gradually from the 1950s, with some indication of stabilisation since 2010, which may be compatible with a birth cohort effect by sun-protective measures and screening. To study the trajectories ahead a trend analysis was applied. Numbers of people with cutaneous melanoma as underlying cause of death from 1950 to 2018 and population data were derived from Statistics Netherlands. A graphical approach was used to explore trends in mortality by age, calendar period, and cohorts born in the successive periods of 1889 to 1979. Age-period-cohort modelling outcomes and population forecasts provided projections of mortality until 2045. Based on 24,151 cases of melanoma death (13,256 men, 10,895 women), age-standardised mortality rates were similar from 1950 to 1989 for both genders, and increased thereafter more in men. The age-curve patterns changed gradually towards higher death rates at older age, implying the existence of a birth cohort effect. The age-period-cohort models showed an increase in melanoma mortality rates in successive generations. For women, the birth cohort effect plateaued for generations born since the mid-1980s. The projected total mortality number was predicted to rise in the next 3 decades.It is concluded that a small future decline of mortality in younger generations can be expected in the Netherlands, but mortality is still rising for the total population.

Long-Term Declines of Thyroid Cancer Mortality: An International Age-Period-Cohort Analysis

Background: Thyroid cancer (TC) incidence rates have been increasing in many countries, predominantly due to overdiagnosis. It is, however, not yet clear whether a true increase in exposure to risk factors might have also contributed to the TC epidemic. We assessed the TC mortality trends, which should not be affected by overdiagnosis, to disentangle the specific contribution of period and cohort effects. Methods: We analyzed long-term mortality data in 24 countries from 5 continents using age-period-cohort (APC) models. Nonidentifiability of the APC models was circumvented by integrating evidence of a consistent relationship between age and TC mortality, allowing to estimate period and cohort linear effects. Results: Substantial heterogeneity existed in the historical TC mortality rates across countries, but long-term rates declined over time in most of the countries, converging around a value of 0.5/100,000. The shape of the age-specific curves was consistently similar across countries and periods, resembling straight lines on the log-log scale, with the slopes ranging between 4.0 and 6.0. Both period and cohort effects showed long-term declines in most countries for both genders. In some countries, such as the United States, Canada, and Australia, substantial long-term declines by period were visible until the 1980s and 1990s, but then stabilized or increased slightly. Declining cohort effects were also seen in almost all countries, and were particularly pronounced in women from Switzerland, whereas stable cohort effects were recorded in South Africa. Although there were some indications of possible increasing risks of deaths among the youngest generations in some countries for both men and women, changes are too recent to be treated as unequivocal and estimates suffered from large statistical variability due to small numbers of deaths. Conclusions: Global long-term declines in TC mortality have been accompanied by downward trends in both period and cohort effects. Our results suggest lack of evidence of a possible major contribution of "real" risk factors in TC mortality, and indirectly confirm the main role of overdiagnosis in the epidemic of TC incidence.

Predictions of Mortality from Pleural Mesothelioma in Italy After the Ban of Asbestos Use

Even if the epidemic of malignant pleural mesothelioma (MPM) is still far from being over worldwide, the health effects of regulations banning asbestos can be evaluated in the countries that implemented them early. Estimates of MPM future burden can be useful to inform and support the implementation of anti-asbestos health policies all around the world. With this aim we described the trends of MPM deaths in Italy (1970-2014) and predicted the future number of cases in both sexes (2015-2039), with consideration of the national asbestos ban that was issued in 1992. The Italian National Statistical Institute (ISTAT) provided MPM mortality figures. Cases ranging from 25 to 89 years of age were included in the analysis. For each five-year period from 1970 to 2014, mortality rates were calculated and age-period-cohort Poisson models were used to predict future burden of MPM cases until 2039. During the period 1970-2014 a total number of 28,907 MPM deaths were observed. MPM deaths increased constantly over the study period, ranging from 1356 cases in 1970-1974 to 5844 cases in 2010-2014. The peak of MPM cases is expected to be reached in the period 2020-2024 (about 7000 cases). The decrease will be slow: about 26,000 MPM cases are expected to occur in Italy during the next 20 years (2020-2039). The MPM epidemic in Italy is far from being concluded despite the national ban implemented in 1992, and the peak is expected in 2020-2024, in both sexes. Our results are consistent with international literature.

The Importance of the Baby Boom Cohort and the Great Recession in Understanding Age, Period, and Cohort Patterns in Happiness

Twenge, Sherman, and Lyubomirsky (TSL) claim that long-term cultural changes have increased young adults' happiness while reducing mature adults' happiness. To establish their conclusion, TSL use trend analyses, as well as more sophisticated mixed-effects models, but their analyses are problematic. In particular, TSL's trend analyses ignore a crucial cohort effect: well-known lower happiness among baby boomers. Furthermore, their data aggregation obscures the ephemerality of a recent period effect: the Great Recession. Finally, TSL overlook a key finding of their mixed-effects models that both pre- and post-Boomer cohorts became happier as they aged from young to mature adults. Our reanalyses of the data establish that the Baby Boomer cohort, the short-lived Great Recession, and unfortunate data aggregation account for TSL's results. The well-established, long-term relationship between age and happiness remains as it has been for decades despite any cultural shifts that may have occurred disfavoring mature adults.

An age-period-cohort analysis of cancer incidence among the oldest old, Utah 1973-2002

We used age-period-cohort (APC) analyses to describe the simultaneous effects of age, period, and cohort on cancer incidence rates in an attempt to understand the population dynamics underlying their patterns among those aged 85+. Data from the Utah Cancer Registry (UCR), the US Census, the National Center for Health Statistics (NCHS), and the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) programme were used to generate age-specific estimates of cancer incidence at ages 65-99 from 1973 to 2002 for Utah. Our results showed increasing cancer incidence rates up to the 85-89 age group followed by declines at ages 90-99 when not confounded by the separate influences of period and cohort effects. We found significant period and cohort effects, suggesting the role of environmental mechanisms in cancer incidence trends between the ages of 85 and 100.