Semi-analytical computation of heteroclinic connections between center manifolds with the parameterization method

This paper presents methodology for the computation of whole sets of heteroclinic connections between iso-energetic slices of center manifolds of center x center x saddle fixed points of autonomous Hamiltonian systems. It involves: (a) computing Taylor expansions of the center-unstable and center-stable manifolds of the departing and arriving fixed points through the parameterization method, using a new style that uncouples the center part from the hyperbolic one, thus making the fibered structure of the manifolds explicit; (b) uniformly meshing iso-energetic slices of the center manifolds, using a novel strategy that avoids numerical integration of the reduced differential equations and makes an explicit 3D representation of these slices as deformed solid ellipsoids; (c) matching the center-stable and center-unstable manifolds of the departing and arriving points in a Poincar\'e section. The methodology is applied to obtain the whole set of iso-energetic heteroclinic connections from the center manifold of L2 to the center manifold of L1 in the Earth-Moon circular, spatial Restricted Three-Body Problem, for nine increasing energy levels that reach the appearance of Halo orbits in both L1 and L2. Some comments are made on possible applications to space mission design.Comment: 36 pages, 14 figure

Psychotic-Like Experiences and Nonsuicidal Self-Injury in England: Results from a National Survey

Correction in the title (Jan 2016) https://doi.org/10.1371/journal.pone.0147095Background: Little is known about the association between psychotic-like experiences (PLEs) and nonsuicidal self-injury (NSSI) in the general adult population. Thus, the aim of this study was to examine the association using nationally-representative data from England. Methods: Data from the 2007 Adult Psychiatric Morbidity Survey was analyzed. The sample consisted of 7403 adults aged ≥16 years. Five forms of PLEs (mania/hypomania, thought control, paranoia, strange experience, auditory hallucination) were assessed with the Psychosis Screening Questionnaire. The association between PLEs and NSSI was assessed by multivariable logistic regression. Hierarchical models were constructed to evaluate the influence of alcohol and drug dependence, common mental disorders, and borderline personality disorder symptoms on this association. Results: The prevalence of NSSI was 4.7% (female 5.2% and male 4.2%), while the figures among those with and without any PLEs were 19.2% and 3.9% respectively. In a regression model adjusted for sociodemographic factors and stressful life events, most types of PLE were significantly associated with NSSI: paranoia (OR 3.57; 95%CI 1.96-6.52), thought control (OR 2.45; 95%CI 1.05-5.74), strange experience (OR 3.13; 95%CI 1.99-4.93), auditory hallucination (OR 4.03; 95%CI 1.56-10.42), and any PLE (OR 2.78; 95%CI 1.88-4.11). The inclusion of borderline personality disorder symptoms in the models had a strong influence on the association between PLEs and NSSI as evidenced by a large attenuation in the ORs for PLEs, with only paranoia continuing to be significantly associated with NSSI. Substance dependence and common mental disorders had little influence on the association between PLEs and NSSI. Conclusions: Borderline personality disorder symptoms may be an important factor in the link between PLEs and NSSI. Future studies on PLEs and NSSI should take these symptoms into account

Correction: Psychotic-Like Experiences and Nonsuidical Self-Injury in England: Results from a National Survey

The word "Nonsuicidal" is misspelled in the title. The correct title is: Psychotic-Like Experiences and Nonsuicidal Self-Injury in England: Results from a National Surve

Relationship between living alone and common mental disorders in the 1993, 2000 and 2007 National Psychiatric Morbidity Surveys

Given the high prevalence of common mental disorders (CMDs) and individuals living alone in the United Kingdom, the goal of this study using English nationally representative data was to examine the association between living alone and CMDs, and to identify potential mediating factors of this association. The data were drawn from the 1993, 2000 and 2007 National Psychiatric Morbidity Surveys. CMDs were assessed using the Clinical Interview Schedule-Revised (CIS-R), a questionnaire focusing on past week neurotic symptoms. The presence of CMDs was defined as a CIS-R total score of 12 and above. Multivariable logistic regression and mediation analyses were conducted to analyze the association between living alone and CMDs, and to identify mediators in this association. The prevalence of CMDs was higher in individuals living alone than in those not living alone in all survey years. Multivariable analysis showed a positive association between living alone and CMDs in all survey years (1993: odds ratio [OR] = 1.69; 2000: OR = 1.63; and 2007: OR = 1.88). Overall, loneliness explained 84% of the living alone-CMD association. Living alone was positively associated with CMDs. Interventions addressing loneliness among individuals living alone may be particularly important for the mental wellbeing of this vulnerable population

Physical multimorbidity and subjective cognitive complaints among adults in the United Kingdom: a cross-sectional community-based study

Our goal was to examine the association between physical multimorbidity and subjective cognitive complaints (SCC) using UK nationally representative cross-sectional community-based data, and to quantify the extent to which a broad range of mainly psychological and behavioral factors explain this relationship. Data from the 2007 Adult Psychiatric Morbidity Survey were analyzed [N = 7399 adults, mean (SD) age 46.3 (18.6) years, 48.6% men]. Multimorbidity was defined as ≥2 physical diseases. SCC included two different cognitive constructs: subjective concentration and memory complaints. Multivariable logistic regression and mediation analyses were conducted. Multimorbidity was associated with higher prevalence of subjective concentration (30.7% vs. 17.3%) and memory complaints (42.8% vs. 22.9%) compared to no multimorbidity. In the regression model adjusted for sociodemographics, multimorbidity was associated with subjective concentration (OR = 2.58; 95% CI = 2.25-2.96) and memory complaints (OR = 2.34; 95% CI = 2.08-2.62). Sleep problems, stressful life events and any anxiety disorder explained 21-23%, 20-22% and 14-15% of the multimorbidity-SCC association, respectively. Multimorbidity and SCC are highly co-morbid. The utility of SCC screening in identifying individuals at high risk for future cognitive decline among individuals with multimorbidity should be assessed

Global, regional, and national burden of neurological disorders, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

Neurological disorders are increasingly recognised as major causes of death and disability worldwide. The aim of this analysis from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016 is to provide the most comprehensive and up-to-date estimates of the global, regional, and national burden from neurological disorders. METHODS: We estimated prevalence, incidence, deaths, and disability-adjusted life-years (DALYs; the sum of years of life lost [YLLs] and years lived with disability [YLDs]) by age and sex for 15 neurological disorder categories (tetanus, meningitis, encephalitis, stroke, brain and other CNS cancers, traumatic brain injury, spinal cord injury, Alzheimer's disease and other dementias, Parkinson's disease, multiple sclerosis, motor neuron diseases, idiopathic epilepsy, migraine, tension-type headache, and a residual category for other less common neurological disorders) in 195 countries from 1990 to 2016. DisMod-MR 2.1, a Bayesian meta-regression tool, was the main method of estimation of prevalence and incidence, and the Cause of Death Ensemble model (CODEm) was used for mortality estimation. We quantified the contribution of 84 risks and combinations of risk to the disease estimates for the 15 neurological disorder categories using the GBD comparative risk assessment approach. FINDINGS: Globally, in 2016, neurological disorders were the leading cause of DALYs (276 million [95% UI 247-308]) and second leading cause of deaths (9·0 million [8·8-9·4]). The absolute number of deaths and DALYs from all neurological disorders combined increased (deaths by 39% [34-44] and DALYs by 15% [9-21]) whereas their age-standardised rates decreased (deaths by 28% [26-30] and DALYs by 27% [24-31]) between 1990 and 2016. The only neurological disorders that had a decrease in rates and absolute numbers of deaths and DALYs were tetanus, meningitis, and encephalitis. The four largest contributors of neurological DALYs were stroke (42·2% [38·6-46·1]), migraine (16·3% [11·7-20·8]), Alzheimer's and other dementias (10·4% [9·0-12·1]), and meningitis (7·9% [6·6-10·4]). For the combined neurological disorders, age-standardised DALY rates were significantly higher in males than in females (male-to-female ratio 1·12 [1·05-1·20]), but migraine, multiple sclerosis, and tension-type headache were more common and caused more burden in females, with male-to-female ratios of less than 0·7. The 84 risks quantified in GBD explain less than 10% of neurological disorder DALY burdens, except stroke, for which 88·8% (86·5-90·9) of DALYs are attributable to risk factors, and to a lesser extent Alzheimer's disease and other dementias (22·3% [11·8-35·1] of DALYs are risk attributable) and idiopathic epilepsy (14·1% [10·8-17·5] of DALYs are risk attributable). INTERPRETATION: Globally, the burden of neurological disorders, as measured by the absolute number of DALYs, continues to increase. As populations are growing and ageing, and the prevalence of major disabling neurological disorders steeply increases with age, governments will face increasing demand for treatment, rehabilitation, and support services for neurological disorders. The scarcity of established modifiable risks for most of the neurological burden demonstrates that new knowledge is required to develop effective prevention and treatment strategies

Clinical features, comorbidity, and cognitive impairment in elderly bipolar patients

INTRODUCTION: Data specific to late-life bipolar disorder (BD) are limited. Current research is sparse and present guidelines are not adapted to this group of patients. OBJECTIVES: We present a literature review on clinical characteristics, comorbidities, and cognitive impairment in patients with late-life BD. This review discusses common comorbidities that affect BD elders and how aging might affect cognition and treatment. METHODS: Eligible studies were identified in MedLine by the Medical Subject Headings terms 'bipolar disorder' and 'aged'. We only included original research reports published in English between 2012 and 2015. RESULTS: From 414 articles extracted, 16 studies were included in the review. Cardiovascular and respiratory conditions, type II diabetes, and endocrinological abnormalities were observed as highly prevalent. BD is associated with a high suicide risk. Bipolar elderly had an increased risk of dementia and performed worse on cognitive screening tests compared to age-matched controls across different levels of cognition. Despite high rates of medical comorbidity among bipolar elderly, a systematic under-recognition and undertreatment of cardiovascular disease have been suggested. CONCLUSION: There was a high burden of physical comorbidities and cognitive impairment in late-life BD. Bipolar elderly might be under-recorded and undertreated in primary medical care, indicating that this group needs an adapted clinical assessment and specific clinical guidelines need to be established

Population and fertility by age and sex for 195 countries and territories, 1950-2017: a systematic analysis for the Global Burden of Disease Study 2017

BACKGROUND: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. METHODS: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10-54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10-14 years and 50-54 years was estimated from data on fertility in women aged 15-19 years and 45-49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories

Migration and mental health in Europe (the state of the mental health in Europe working group: appendix 1)

BACKGROUND: This paper is a part of the work of the group that carried out the report "The state of the mental health in Europe" (European Commission, DG Health and Consumer Protection, 2004) and deals with the mental health issues related to the migration in Europe. METHODS: The paper tries to describe the social, demographical and political context of the emigration in Europe and tries to indicate the needs and (mental) health problems of immigrants. A review of the literature concerning mental health risk in immigrant is also carried out. The work also faces the problem of the health policy toward immigrants and the access to health care services in Europe. RESULTS: Migration during the 1990s has been high and characterised by new migrations. Some countries in Europe, that have been traditionally exporters of migrants have shifted to become importers. Migration has been a key force in the demographic changes of the European population. The policy of closed borders do not stop migration, but rather seems to set up a new underclass of so-called "illegals" who are suppressed and highly exploited. In 2000 there were also 392.200 asylum applications. The reviewed literature among mental health risk in some immigrant groups in Europe concerns: 1) highest rate of schizophrenia; suicide; alcohol and drug abuse; access of psychiatric facilities; risk of anxiety and depression; mental health of EU immigrants once they returned to their country; early EU immigrants in today disadvantaged countries; refugees and mental health Due to the different condition of migration concerning variables as: motivation to migrations (e.g. settler, refugees, gastarbeiters); distance for the host culture; ability to develop mediating structures; legal residential status it is impossible to consider "migrants" as a homogeneous group concerning the risk for mental illness. In this sense, psychosocial studies should be undertaken to identify those factors which may under given conditions, imply an increased risk of psychiatric disorders and influence seeking for psychiatric care. COMMENTS AND REMARKS: Despite in the migrants some vulnerable groups were identified with respect to health problems, in many European countries there are migrants who fall outside the existing health and social services, something which is particularly true for asylum seekers and undocumented immigrants. In order to address these deficiencies, it is necessary to provide with an adequate financing and a continuity of the grants for research into the multicultural health demand. Finally, there is to highlight the importance of adopting an integrated approach to mental health care that moves away from psychiatric care only

Global, regional, and national age-sex-specific mortality for 282 causes of death in 195 countries and territories, 1980-2017: a systematic analysis for the Global Burden of Disease Study 2017

BACKGROUND: Global development goals increasingly rely on country-specific estimates for benchmarking a nation's progress. To meet this need, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016 estimated global, regional, national, and, for selected locations, subnational cause-specific mortality beginning in the year 1980. Here we report an update to that study, making use of newly available data and improved methods. GBD 2017 provides a comprehensive assessment of cause-specific mortality for 282 causes in 195 countries and territories from 1980 to 2017. METHODS: The causes of death database is composed of vital registration (VR), verbal autopsy (VA), registry, survey, police, and surveillance data. GBD 2017 added ten VA studies, 127 country-years of VR data, 502 cancer-registry country-years, and an additional surveillance country-year. Expansions of the GBD cause of death hierarchy resulted in 18 additional causes estimated for GBD 2017. Newly available data led to subnational estimates for five additional countries-Ethiopia, Iran, New Zealand, Norway, and Russia. Deaths assigned International Classification of Diseases (ICD) codes for non-specific, implausible, or intermediate causes of death were reassigned to underlying causes by redistribution algorithms that were incorporated into uncertainty estimation. We used statistical modelling tools developed for GBD, including the Cause of Death Ensemble model (CODEm), to generate cause fractions and cause-specific death rates for each location, year, age, and sex. Instead of using UN estimates as in previous versions, GBD 2017 independently estimated population size and fertility rate for all locations. Years of life lost (YLLs) were then calculated as the sum of each death multiplied by the standard life expectancy at each age. All rates reported here are age-standardised