Predicting the prevalence of type 2 diabetes in Brazil: a modeling study

Aims

We adopted a modeling approach to predict the likely future prevalence of type 2 diabetes, taking into account demographic changes and trends in obesity and smoking in Brazil. We then used the model to estimate the likely future impact of different policy scenarios, such as policies to reduce obesity.

Methods

The IMPACT TYPE 2 DIABETES model uses a Markov approach to integrate population, obesity, and smoking trends to estimate future type 2 diabetes prevalence. We developed a model for the Brazilian population from 2006 to 2036. Data on the Brazilian population in relation to sex and age were collected from the Brazilian Institute of Geography and Statistics, and data on the prevalence of type 2 diabetes, obesity, and smoking were collected from the Surveillance of Risk and Protection Factors for Chronic Diseases by Telephone Survey (VIGITEL).

Results

The observed prevalence of type 2 diabetes among Brazilians aged over 25 years was 10.8% (5.2-14.3%) in 2006, increasing to 13.7% (6.9-18.4%) in 2020. Between 2006 and 2020, the observed prevalence in men increased from 11.0 to 19.1% and women from 10.6 to 21.3%. The model forecasts a dramatic rise in prevalence by 2036 (27.0% overall, 17.1% in men and 35.9% in women). However, if obesity prevalence declines by 1% per year from 2020 to 2036 (Scenario 1), the prevalence of diabetes decreases from 26.3 to 23.7, which represents approximately a 10.0% drop in 16 years. If obesity declined by 5% per year in 16 years as an optimistic target (Scenario 2), the prevalence of diabetes decreased from 26.3 to 21.2, representing a 19.4% drop in diabetes prevalence.

Conclusion

The model predicts an increase in the prevalence of type 2 diabetes in Brazil. Even with ambitious targets to reduce obesity prevalence, type 2 diabetes in Brazil will continue to have a large impact on Brazilian public health.

Birthweights at term have increased globally: insights from a systematic review of 183 million births

OBJECTIVE

This study aimed to assess global trends in mean birthweights at term, as reported in peer-reviewed literature.

DATA SOURCES

We electronically searched PubMed, Embase, and Web of Science up to September 2023, using combinations of the search terms: "birth weight"; "birth-weight"; "birthweight"; "trend". There were no restrictions based on language or geographic area.

STUDY ELIGIBILITY CRITERIA

We included all ecological and observational studies reporting mean birthweight at term as a continuous numerical variable over time.

METHODS

We assessed the quality of included studies using the Dufault and Klar checklist modified by Betran et al. Univariate and multivariate linear models were used to examine the effects of time (years) and geographical origins. Subgroup analyses focused on national data sources and on data collected from 1950 onward.

RESULTS

Among 6447 reviewed articles, 29 met our criteria, reporting mean birthweight data from over 183 million infants worldwide. Most studies were hospital-based (48.3%), 44.8% used national data, and a minority used municipality, community, or regional data (6.9%). Geographically, North America (31.0%) had the highest representation, followed by Asia and Europe (27.6% each), and South America and Oceania (6.9% each). Our univariate linear regression model (Model 1) revealed a significant increase in mean birthweight at term over time (4.74 g/y; 95% confidence interval, 3.95-5.53; P<.001). Model 2, incorporating continental dummy variables into the first model, confirmed this trend (3.85 g/y; 95% confidence interval, 2.96-4.74; P<.001). Model 3, focusing on available national data, did not find a significant relationship. Model 4 narrowed its focus on records from 1950 onward, reporting a robust annual increase of 7.26 g/y (95% confidence interval, 6.19-8.33; P<.001). Model 5, adjusting for the number of participants included in each study, reported a conclusive mean term birthweight increase of 1.46 g/y (95% confidence interval, 0.74-2.18; P<.001).

CONCLUSION

This systematic review of 29 studies shows an increase in term birthweights over time, particularly when considering data since 1950. Limitations include study quality variations, data source diversity, and data sparsity, underscoring the need for future research to use precise gestational age distinctions and predetermined time frames to gain a deeper understanding of this trend and its implications for maternal and child health.

A genetic history of the Balkans from Roman frontier to Slavic migrations

The rise and fall of the Roman Empire was a socio-political process with enormous ramifications for human history. The Middle Danube was a crucial frontier and a crossroads for population and cultural movement. Here, we present genome-wide data from 136 Balkan individuals dated to the 1st millennium CE. Despite extensive militarization and cultural influence, we find little ancestry contribution from peoples of Italic descent. However, we trace a large-scale influx of people of Anatolian ancestry during the Imperial period. Between ∼250 and 550 CE, we detect migrants with ancestry from Central/Northern Europe and the Steppe, confirming that "barbarian" migrations were propelled by ethnically diverse confederations. Following the end of Roman control, we detect the large-scale arrival of individuals who were genetically similar to modern Eastern European Slavic-speaking populations, who contributed 30%-60% of the ancestry of Balkan people, representing one of the largest permanent demographic changes anywhere in Europe during the Migration Period.

Do Demographic Increases in LGBT and Nonreligious Americans Increase Threat?

Building on previous research demonstrating that demographic growth of racial minorities increases realistic threat and prejudice among majority group members, we examined whether demographic increases of groups associated with symbolic threat (lesbian, gay, bisexual, and transgender [LGBT] and nonreligious groups) increased realistic threat, symbolic threat, and/or prejudice. In a single-paper meta-analysis across four studies, participants who read that LGBT groups were becoming more prevalent in the United States exhibited heightened perceptions of realistic threat and (especially) symbolic threat from these groups, which in turn predicted anti-LGBT prejudice. Two similar studies examining the growth of nonreligious groups demonstrated weaker effects. Implications for America's growing diversity and future directions for studying these effects are discussed.

Dramatic decline in a titi monkey population after the 2016-2018 sylvatic yellow fever outbreak in Brazil

Platyrrhini are highly vulnerable to the yellow fever (YF) virus. From 2016 to 2018, the Atlantic Forest of southeast Brazil faced its worst sylvatic YF outbreak in about a century, thought to have killed thousands of primates. It is essential to assess the impact of this epidemic on threatened primate assemblages to design effective conservation strategies. In this study, we assessed the impact of the 2016-2018 YF outbreak on a geographically isolated population of Near Threatened black-fronted titi monkeys (Callicebus nigrifrons) in two Atlantic Forest patches of the Santuário do Caraça, MG, Brazil. Extensive preoutbreak monitoring, conducted between 2008 and 2016, revealed that the home range and group sizes of the population remained stable. In 2016, the population size was estimated at 53-57 individuals in 11-12 groups. We conducted monitoring and playback surveys in 2019 and found that the population had decreased by 68% in one forest patch and completely vanished in the other, resulting in a combined decline of 80%. We discuss this severe loss of a previously stable population and conclude that it was highly likely caused by the YF outbreak. The remaining population is at risk of disappearing completely because of its small size and geographic isolation. A systematic population surveys of C. nigrifrons, along other sensible Platyrrhini species, is needed to re-evaluate their current conservation status.

Transposable element landscapes illuminate past evolutionary events in the endangered fern Vandenboschia speciosa

Vandenboschia speciosa is an endangered tetraploid fern species with a large genome (10.5 Gb). Its geographical distribution is characterized by disjoined tertiary flora refuges, with relict populations that survived past climate crises. Here, we analyzed the transposable elements (TEs) and found that they comprise approximately 76% of the V. speciosa genome, thus being the most abundant type of DNA sequence in this gigantic genome. The V. speciosa genome is composed of 51% and 5.6% of Class I and Class II elements, respectively. LTR retrotransposons were the most abundant TEs in this species (at least 42% of the genome), followed by non-LTR retrotransposons, which constituted at least 8.7% of the genome of this species. We introduce an additional analysis to identify the nature of non-annotated elements (19% of the genome). A BLAST search of the non-annotated contigs against the V. speciosa TE database allowed for the identification of almost half of them, which were most likely diverged sequence variants of the annotated TEs. In general, the TE composition in V. speciosa resembles the TE composition in seed plants. In addition, repeat landscapes revealed three episodes of amplification for all TEs, most likely due to demographic changes associated with past climate crises.

Female social structure influences, and is influenced by, male introduction and integration success among captive rhesus macaques (Macaca mulatta)

Animal social structure is influenced by multiple socioecological factors. Of these, the links between changes to group demography through the arrival of new individuals and residents' social structure remain unclear. Across seven groups of captive rhesus macaques (Macaca mulatta), we examine how male introductions may be influenced by, and in-turn influence, aspects of female social structure. GLMMs revealed that males integrated more successfully into groups in which females showed more 'despotic' social structures, i.e., higher aggression rates, steeper dominance hierarchies, and greater rank-skew in allogrooming network connectedness. Yet during periods that followed males' social integration, females increased their social tolerance (decreased aggression and shallower hierarchies) and group cohesivity (less clustered allogrooming networks), but retained their tendencies to groom dominants. Our findings, independent of group size and matrilineal relatedness, help better understand how dispersal/immigration may influence social structure, and how assessing changes to social structure may inform macaque welfare and management.

Studying models of balancing selection using phase-type theory

Balancing selection (BLS) is the evolutionary force that maintains high levels of genetic variability in many important genes. To further our understanding of its evolutionary significance, we analyze models with BLS acting on a biallelic locus: an equilibrium model with long-term BLS, a model with long-term BLS and recent changes in population size, and a model of recent BLS. Using phase-type theory, a mathematical tool for analyzing continuous time Markov chains with an absorbing state, we examine how BLS affects polymorphism patterns in linked neutral regions, as summarized by nucleotide diversity, the expected number of segregating sites, the site frequency spectrum, and the level of linkage disequilibrium (LD). Long-term BLS affects polymorphism patterns in a relatively small genomic neighborhood, and such selection targets are easier to detect when the equilibrium frequencies of the selected variants are close to 50%, or when there has been a population size reduction. For a new mutation subject to BLS, its initial increase in frequency in the population causes linked neutral regions to have reduced diversity, an excess of both high and low frequency derived variants, and elevated LD with the selected locus. These patterns are similar to those produced by selective sweeps, but the effects of recent BLS are weaker. Nonetheless, compared to selective sweeps, nonequilibrium polymorphism and LD patterns persist for a much longer period under recent BLS, which may increase the chance of detecting such selection targets. An R package for analyzing these models, among others (e.g., isolation with migration), is available.

Religiosity and Health Through the Decades: Is There a Gender Difference?

PURPOSE

An empirical examination of the long-term association, disaggregated by gender, between religiosity and self-rated health with reference to demographic shifts in labor force participation, education, and income.

DESIGN

General Social Survey data.

SETTING

United States, 1974 to 2012.

PARTICIPANTS

A total of 23 353 respondents.

MEASURES

Self-assessed health; 2 key religiosity variables: attendance and intensity of belief; income, labor market variables, education, standard demographic variables, household size, region, and time dummies.

ANALYSIS

Probit estimation conducted for the aggregate sample by gender as well as by decades to examine possible gender differential changes over time.

RESULTS

Attendance has declined overall with a much greater decline for women. The overall positive association between religiosity and health masks considerable heterogeneity across gender and time; higher and stable for males, there is no longer a significant association for females. Increased education, income, and labor force participation can explain only part of this association. Education is the strongest mediator.

CONCLUSION

The way women and men benefit from religious attendance has changed, suggesting that some pathways may be working differently for women now, especially those with less education. Moving away from church networks could be due to a perceived lack of support or substitution by other social networks. Ceteris paribus, since religious participation has been shown to weaken preference for risky consumption, declining participation, especially for women, may show up as an increase in risky behavior.

Tackling Noncommunicable Diseases in Africa: Caveat Lector

Noncommunicable disease (NCD), principally cardiovascular diseases, cancer, chronic lung disease, and diabetes, constitutes the major cause of death worldwide. Evidence of a continuing increase in the global burden of these diseases has generated recent urgent calls for global action to tackle and reduce related death and disability. Because the majority of NCD deaths occur in low- and middle-income countries, increased attention has been focused on this group of countries. However, in sub-Saharan Africa, where all countries are members of the low- and middle-income grouping, NCDs are not the leading causes of death or potential life years lost. Thus, strategies to tackle NCDs in sub-Saharan Africa are best conceived and executed in alignment with existing strategies for the prevention, treatment, and control of the actual leading causes of death in this region. This commentary addresses caveats to be considered as strategies are developed to tackle NCDs in sub-Saharan Africa as part of the global effort to prevent, treat, and control NCDs.

Delivering the evidence--skill mix and education for elder care

OBJECTIVES

To review the current status of dental curricula on elder care, and the current curricula regarding elder care, and it's effect on altering practitioner behaviors while addressing the needs of a growing North American elder population.

BACKGROUND

An impending crisis is looming over the oral healthcare of our aging population. At the same moment that life expectancy is being extended through increasingly complex healthcare improvements, the numbers of trained dental providers capable and interested in delivering the needed care is failing to grow at an adequate rate.

DISCUSSION

The skills necessary to manage these increasingly complex patients require an interprofessional approach capable of delivering care to sicker patients, in a variety of living accommodations, while managing a variety of care givers. The dental skills necessary to treat these elderly are modifications of skills students routinely learn in dental school. As a matter of fact, the skills students acquire to treat an adult patient population may be contrary to the basic skills necessary to manage the elderly dependent adult patient. Teaching students the nuance differences needed to properly diagnose and care for this population is a difficult task that must be taught in a contextual environment.

CONCLUSION

Significant changes in the teaching of dental management of the elderly are critical within much of the education community. Just as teaching students to care for the pediatric population as general dentists, the clinical education must involve a sufficient number of quality experiences to address issues of both competency, that of the graduate to perform care independently, and attitudes, the actually willingness to treat the elderly.

More Diverse Yet Less Tolerant? How the Increasingly Diverse Racial Landscape Affects White Americans' Racial Attitudes

Recent Census Bureau projections indicate that racial/ethnic minorities will comprise over 50% of the U.S. population by 2042, effectively creating a so-called "majority-minority" nation. Across four experiments, we explore how presenting information about these changing racial demographics influences White Americans' racial attitudes. Results reveal that exposure to the changing demographics evokes the expression of greater explicit and implicit racial bias. Specifically, Whites exposed to the racial demographic shift information preferred interactions/settings with their own ethnic group over minority ethnic groups; expressed more negative attitudes toward Latinos, Blacks, and Asian Americans; and expressed more automatic pro-White/anti-minority bias. Perceived threat to Whites' societal status mediated the effects of the racial shift information on explicit racial attitudes. These results suggest that rather than ushering in a more tolerant future, the increasing diversity of the nation may instead yield intergroup hostility. Implications for intergroup relations and media framing of the racial shift are discussed.