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Nature Jan 2024Multiple sclerosis (MS) is a neuro-inflammatory and neurodegenerative disease that is most prevalent in Northern Europe. Although it is known that inherited risk for MS...
Multiple sclerosis (MS) is a neuro-inflammatory and neurodegenerative disease that is most prevalent in Northern Europe. Although it is known that inherited risk for MS is located within or in close proximity to immune-related genes, it is unknown when, where and how this genetic risk originated. Here, by using a large ancient genome dataset from the Mesolithic period to the Bronze Age, along with new Medieval and post-Medieval genomes, we show that the genetic risk for MS rose among pastoralists from the Pontic steppe and was brought into Europe by the Yamnaya-related migration approximately 5,000 years ago. We further show that these MS-associated immunogenetic variants underwent positive selection both within the steppe population and later in Europe, probably driven by pathogenic challenges coinciding with changes in diet, lifestyle and population density. This study highlights the critical importance of the Neolithic period and Bronze Age as determinants of modern immune responses and their subsequent effect on the risk of developing MS in a changing environment.
Topics: Humans; Datasets as Topic; Diet; Europe; Genetic Predisposition to Disease; Genetics, Medical; Genome, Human; Grassland; History, 15th Century; History, Ancient; History, Medieval; Human Migration; Life Style; Multiple Sclerosis; Neurodegenerative Diseases; Population Density
PubMed: 38200296
DOI: 10.1038/s41586-023-06618-z -
JAMA Psychiatry Dec 2023People with psychosis are more likely to be born and live in densely populated and socioeconomically deprived environments, but it is unclear whether these associations...
IMPORTANCE
People with psychosis are more likely to be born and live in densely populated and socioeconomically deprived environments, but it is unclear whether these associations are a cause or consequence of disorder.
OBJECTIVE
To investigate whether trajectories of exposure to deprivation and population density before and after diagnosis are associated with psychotic disorders or nonpsychotic bipolar disorder.
DESIGN, SETTING, AND PARTICIPANTS
This nested case-control study included all individuals born in Sweden between January 1, 1982, and December 31, 2001, diagnosed for the first time with an International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) psychotic disorder or nonpsychotic bipolar disorder between their 15th birthday and cohort exit (December 31, 2016). One sex- and birth year-matched control participant per case was selected. Data analysis was performed from July 2021 to June 2023.
EXPOSURES
The main exposures were quintiles of neighborhood-level deprivation and population density each year from birth to age 14 years and from first diagnosis until cohort exit.
MAIN OUTCOMES AND MEASURES
The main outcomes were the odds of a serious mental illness outcome associated with trajectories of deprivation and population density, before and after diagnosis in cases. Group-based trajectory modeling was used to derive trajectories of each exposure in each period. Logistic regression was used to examine associations with outcomes.
RESULTS
A total of 53 458 individuals (median [IQR] age at diagnosis in case patients, 23.2 [15.0-34.8] years; 30 746 [57.5%] female), including 26 729 case patients and 26 729 control participants, were studied. From birth to early adolescence, gradients were observed in exposure to deprivation and population density trajectories during upbringing and psychotic disorder, with those in the most vs least deprived (adjusted odds ratio [AOR], 1.17; 95% CI, 1.08-1.28) and most vs least densely populated (AOR, 1.49; 95% CI, 1.34-1.66) trajectories at greatest risk. A strong upward mobility trajectory to less deprived neighborhoods was associated with similar risk to living in the least deprived trajectory (AOR, 1.01; 95% CI, 0.91-1.12). Only 543 case patients (2.0%) drifted into more deprived areas after diagnosis; people with psychotic disorder were more likely to belong to this trajectory (AOR, 1.38; 95% CI, 1.16-1.65) or remain in the most deprived trajectory (AOR, 1.36; 95% CI, 1.24-1.48) relative to controls. Patterns were similar for nonpsychotic bipolar disorder and deprivation but weaker for population density.
CONCLUSIONS AND RELEVANCE
In this case-control study, greater exposure to deprivation during upbringing was associated with increased risk of serious mental illness, but upward mobility mitigated this association. People with serious mental illness disproportionately remained living in more deprived areas after diagnosis, highlighting issues of social immobility. Prevention and treatment should be proportionately located in deprived areas according to need.
Topics: Adolescent; Humans; Female; Young Adult; Adult; Male; Population Density; Case-Control Studies; Psychotic Disorders; Bipolar Disorder; Social Deprivation
PubMed: 37672257
DOI: 10.1001/jamapsychiatry.2023.3220 -
International Journal of Epidemiology Aug 2023Reliable and detailed data on the prevalence of tuberculosis (TB) with sub-national estimates are scarce in Ethiopia. We address this knowledge gap by spatially... (Review)
Review Meta-Analysis
BACKGROUND
Reliable and detailed data on the prevalence of tuberculosis (TB) with sub-national estimates are scarce in Ethiopia. We address this knowledge gap by spatially predicting the national, sub-national and local prevalence of TB, and identifying drivers of TB prevalence across the country.
METHODS
TB prevalence data were obtained from the Ethiopia national TB prevalence survey and from a comprehensive review of published reports. Geospatial covariates were obtained from publicly available sources. A random effects meta-analysis was used to estimate a pooled prevalence of TB at the national level, and model-based geostatistics were used to estimate the spatial variation of TB prevalence at sub-national and local levels. Within the MBG Plugin Framework, a logistic regression model was fitted to TB prevalence data using both fixed covariate effects and spatial random effects to identify drivers of TB and to predict the prevalence of TB.
RESULTS
The overall pooled prevalence of TB in Ethiopia was 0.19% [95% confidence intervals (CI): 0.12%-0.28%]. There was a high degree of heterogeneity in the prevalence of TB (I2 96.4%, P <0.001), which varied by geographical locations, data collection periods and diagnostic methods. The highest prevalence of TB was observed in Dire Dawa (0.96%), Gambela (0.88%), Somali (0.42%), Addis Ababa (0.28%) and Afar (0.24%) regions. Nationally, there was a decline in TB prevalence from 0.18% in 2001 to 0.04% in 2009. However, prevalence increased back to 0.29% in 2014. Substantial spatial variation of TB prevalence was observed at a regional level, with a higher prevalence observed in the border regions, and at a local level within regions. The spatial distribution of TB prevalence was positively associated with population density.
CONCLUSION
The results of this study showed that TB prevalence varied substantially at sub-national and local levels in Ethiopia. Spatial patterns were associated with population density. These results suggest that targeted interventions in high-risk areas may reduce the burden of TB in Ethiopia and additional data collection would be required to make further inferences on TB prevalence in areas that lack data.
Topics: Humans; Ethiopia; Prevalence; Tuberculosis; Logistic Models; Population Density
PubMed: 37164625
DOI: 10.1093/ije/dyad052 -
Trends in Ecology & Evolution Oct 2023Our ability to assess the threat posed by the genetic load to small and declining populations has been greatly improved by advances in genome sequencing and... (Review)
Review
Our ability to assess the threat posed by the genetic load to small and declining populations has been greatly improved by advances in genome sequencing and computational approaches. Yet, considerable confusion remains around the definitions of the genetic load and its dynamics, and how they impact individual fitness and population viability. We illustrate how both selective purging and drift affect the distribution of deleterious mutations during population size decline and recovery. We show how this impacts the composition of the genetic load, and how this affects the extinction risk and recovery potential of populations. We propose a framework to examine load dynamics and advocate for the introduction of load estimates in the management of endangered populations.
Topics: Genetics, Population; Genetic Load; Population Density; Inbreeding; Genetic Variation
PubMed: 37344276
DOI: 10.1016/j.tree.2023.05.008 -
The American Surgeon Nov 2023Rural pediatric firearm injuries require regional pediatric and trauma expertise. We evaluated county-level population density associations with transport, hospital...
BACKGROUND
Rural pediatric firearm injuries require regional pediatric and trauma expertise. We evaluated county-level population density associations with transport, hospital interventions, and patient outcomes at a Level I pediatric trauma center serving a rural, statewide catchment area.
MATERIAL AND METHODS
The trauma registry of the only in-state pediatric trauma center was reviewed for firearm injuries in patients < 18 between 1/2013 and 3/2020. County-level population density was classified according to the United States Office of Management and Budget definitions for rural, micropolitan, and metropolitan areas.
RESULTS
364 patients were identified, including 7 patients who were re-injured. Mean age was 11.3 ± 4.5 y and patients were 79.4% male. 59.3% were transferred from a referring hospital. Median injury severity score was 5 (IQR 1-10); 88.0% required trauma center admission, and 48.2% required operative intervention. 7.4% were injured in a rural county, 46.4% in a micropolitan county, and 46.2% in a metropolitan county. Patients from rural counties were more likely to be unintentionally injured (72.0%) than those from micropolitan (54.4%) or metropolitan counties (44.0%, = .04). While need for inpatient admission and length of stay were similar, those transported from rural counties had significantly longer transport times ( < .01) and less frequent need for operative intervention ( = .03), as well as trends toward lower injury severity ( = .08) and mortality ( = .06).
CONCLUSION
Management of pediatric firearm injury is a unique challenge with significant regional variability. Opportunities exist for outreach, telehealth, and decision support to ensure equitable distribution of resources in rural trauma systems.
LEVEL OF EVIDENCE
Epidemiological, Level III.
Topics: Humans; Child; Male; United States; Adolescent; Female; Triage; Firearms; Population Density; Wounds, Gunshot; Injury Severity Score; Rural Population; Trauma Centers; Retrospective Studies
PubMed: 35993395
DOI: 10.1177/00031348221121554 -
Journal of Mathematical Biology Jul 2023We examine the effect of human mobility on disease prevalence by studying the dependence of the total infected population at endemic equilibria with respect to...
We examine the effect of human mobility on disease prevalence by studying the dependence of the total infected population at endemic equilibria with respect to population diffusion rates of a diffusive epidemic model. For small diffusion rates, our results indicate that the total infected population size is strictly decreasing with respect to the ratio of the diffusion rate of the infected population over that of the susceptible population. Moreover, when the disease local reproductive function is spatially heterogeneous, we found that: (i) for large diffusion rate of the infected population, the total infected population size is strictly maximized at large diffusion rate of the susceptible population when the recovery rate is spatially homogeneous, while it is strictly maximized at intermediate diffusion rate of the susceptible population when the difference of the transmission and recovery rates are spatially homogeneous; (ii) for large diffusion rate of the susceptible population, the total infected population size is strictly maximized at intermediate diffusion rate of the infected population when the recovery rate is spatially homogeneous, while it is strictly minimized at large diffusion rate of the infected population when the difference of the transmission and recovery rates is spatially homogeneous. Numerical simulations are provided to complement the theoretical results. Our studies may provide some insight into the impact of human mobility on disease outbreaks and the severity of epidemics.
Topics: Humans; Prevalence; Population Density; Diffusion; Disease Outbreaks; Epidemics
PubMed: 37392280
DOI: 10.1007/s00285-023-01953-1 -
Nature Sep 2023The wildland-urban interface (WUI) is where buildings and wildland vegetation meet or intermingle. It is where human-environmental conflicts and risks can be...
The wildland-urban interface (WUI) is where buildings and wildland vegetation meet or intermingle. It is where human-environmental conflicts and risks can be concentrated, including the loss of houses and lives to wildfire, habitat loss and fragmentation and the spread of zoonotic diseases. However, a global analysis of the WUI has been lacking. Here, we present a global map of the 2020 WUI at 10 m resolution using a globally consistent and validated approach based on remote sensing-derived datasets of building area and wildland vegetation. We show that the WUI is a global phenomenon, identify many previously undocumented WUI hotspots and highlight the wide range of population density, land cover types and biomass levels in different parts of the global WUI. The WUI covers only 4.7% of the land surface but is home to nearly half its population (3.5 billion). The WUI is especially widespread in Europe (15% of the land area) and the temperate broadleaf and mixed forests biome (18%). Of all people living near 2003-2020 wildfires (0.4 billion), two thirds have their home in the WUI, most of them in Africa (150 million). Given that wildfire activity is predicted to increase because of climate change in many regions, there is a need to understand housing growth and vegetation patterns as drivers of WUI change.
Topics: Humans; Forests; Wildfires; Wilderness; Urbanization; Geographic Mapping; Cities; Africa; Europe; Housing; Population Density; Biomass; Climate Change
PubMed: 37468636
DOI: 10.1038/s41586-023-06320-0 -
Journal of Plant Research Jul 2023Changes in environmental factors, human impact, and interactions between them accelerate the extinction of woody species. Therefore, conservation programs are needed to...
Changes in environmental factors, human impact, and interactions between them accelerate the extinction of woody species. Therefore, conservation programs are needed to protect endangered taxa. However, the relationship between climate, habitat fragmentation, and anthropogenic activities and their consequences are still not well understood. In this work, we aimed to evaluate the impact of climate change and human population density on the Buxus hyrcana Pojark distribution range, as well as the phenomenon of habitat fragmentation. Based on species occurrence data throughout the Hyrcanian Forests (north of Iran), the MAXENT model was employed to estimate the potential distribution and suitability changes. Morphological-spatial analysis (MSPA) and CIRCUITSCAPE were used to assess habitat fragmentation and its connectivity. According to the main results obtained from future scenarios, the potential range will significantly decrease due to the lack of suitable climatic conditions. Meanwhile, B. hyrcana may not be able to shift in potentially suitable areas because of human influence and geographic barriers. Under RCP scenarios the extent of the core area would be reduced and the edge/core ratio significantly increased. Altogether, we found negative effects of the environmental change and the human population density on the continuity of habitats of B. hyrcana. The results of the presented work may improve our knowledge connected with in situ and ex situ protection strategies.
Topics: Humans; Buxus; Population Density; Ecosystem; Forests; Climate Change
PubMed: 37115338
DOI: 10.1007/s10265-023-01457-5 -
Heliyon Sep 2023The objective of the study is to examine the moderating role of population density in the relation between road transportation and environment sustainability of South...
The objective of the study is to examine the moderating role of population density in the relation between road transportation and environment sustainability of South Asian countries from 1990 to 2014. The study uses environment sustainability (population density) as the outcome (moderator), whereas road infrastructure, road density, energy intensity and transportation energy consumption are explanatory variables. The selection of these variables is motivated by their significance in understanding the relationship between road transportation and environmental sustainability. Road infrastructure and road density capture the physical aspects of transportation systems, while energy intensity and road transportation energy consumption provide insights into the energy efficiency and environmental impact of road transport, respectively. The findings show that a positive impact of road infrastructure and road density exists on environmental sustainability. There is contrarily a negative effect of road transportation energy consumption and energy intensity on environmental sustainability. Population density also harms environmental sustainability. When population density is used as a moderator between road transportation energy consumption, energy intensity and environment sustainability, it increases the coefficients of both energy intensity and road transportation energy consumption, which shows that population density plays an enhancing role between road transportation energy consumption, energy intensity and environment sustainability. The coefficients of road density and road infrastructure changed into a negative from a positive in the presence of population density as a moderator, which states that population density plays an antagonistic role between road density and environmental sustainability. We recommend prioritizing sustainable transportation solutions and policies in densely populated areas. Implementing measures such as promoting public transportation and electric vehicles, and investing in infrastructure that supports active transportation modes like cycling and walking can help mitigate the negative environmental effects of transportation while addressing the challenges posed by population density.
PubMed: 37809940
DOI: 10.1016/j.heliyon.2023.e19771 -
Ophthalmology Oct 2023To evaluate the associations of sociodemographic factors with pediatric strabismus diagnosis and outcomes.
PURPOSE
To evaluate the associations of sociodemographic factors with pediatric strabismus diagnosis and outcomes.
DESIGN
Retrospective cohort study.
PARTICIPANTS
American Academy of Ophthalmology IRIS® Registry (Intelligent Research in Sight) patients with strabismus diagnosed before the age of 10 years.
METHODS
Multivariable regression models evaluated the associations of race and ethnicity, insurance, population density, and ophthalmologist ratio with age at strabismus diagnosis, diagnosis of amblyopia, residual amblyopia, and strabismus surgery. Survival analysis evaluated the same predictors of interest with the outcome of time to strabismus surgery.
MAIN OUTCOME MEASURES
Age at strabismus diagnosis, rate of amblyopia and residual amblyopia, and rate of and time to strabismus surgery.
RESULTS
The median age at diagnosis was 5 years (interquartile range, 3-7) for 106 723 children with esotropia (ET) and 54 454 children with exotropia (XT). Amblyopia diagnosis was more likely with Medicaid insurance than commercial insurance (odds ratio [OR], 1.05 for ET; 1.25 for XT; P < 0.01), as was residual amblyopia (OR, 1.70 for ET; 1.53 for XT; P < 0.01). For XT, Black children were more likely to develop residual amblyopia than White children (OR, 1.34; P < 0.01). Children with Medicaid were more likely to undergo surgery and did so sooner after diagnosis (hazard ratio [HR], 1.23 for ET; 1.21 for XT; P < 0.01) than those with commercial insurance. Compared with White children, Black, Hispanic, and Asian children were less likely to undergo ET surgery and received surgery later (all HRs < 0.87; P < 0.01), and Hispanic and Asian children were less likely to undergo XT surgery and received surgery later (all HRs < 0.85; P < 0.01). Increasing population density and clinician ratio were associated with lower HR for ET surgery (P < 0.01).
CONCLUSIONS
Children with strabismus covered by Medicaid insurance had increased odds of amblyopia and underwent strabismus surgery sooner after diagnosis compared with children covered by commercial insurance. After adjusting for insurance status, Black, Hispanic, and Asian children were less likely to receive strabismus surgery with a longer delay between diagnosis and surgery compared with White children.
FINANCIAL DISCLOSURE(S)
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
Topics: Child; Humans; Amblyopia; Ethnicity; Retrospective Studies; Population Density; Visual Acuity; Strabismus; Esotropia; Insurance Coverage
PubMed: 37331481
DOI: 10.1016/j.ophtha.2023.06.008