The association between body mass index and health-related quality of life in the 2017 and 2018 health survey of England data: A cross-sectional observational analysis.

AIM: To provide an updated estimate of the association between body mass index (BMI) and health-related quality of life (HRQoL) among the general population in England and to identify population subgroups with the highest potential utility gains from obesity interventions. MATERIALS AND METHODS: The sample included 12 158 adults with valid HRQoL and BMI data from the 2017 and 2018 Health Survey for England. Robust standard error linear regression, controlling for demographic and socioeconomic characteristics, lifestyle behaviours and obesity-related comorbidities, was used for the baseline analysis. Robustness checks assessed the impact of (a) estimator selection; (b) model specifications; (c) statistical outliers at high BMI; (d) potential BMI measurement error; and (e) data pooling. RESULTS: The study found a significant association between HRQoL and BMI, which exhibited an inverted U-shaped relationship. The mean HRQoL peaked at 25.7 kg/m2 in men and 22.6 kg/m2 in women and was reduced in the underweight, overweight and obesity BMI ranges. Sensitivity analyses reported similar coefficients, suggesting a robust model specification. CONCLUSIONS: Reduced HRQoL beyond optimal BMI underlines the importance of maintaining a normal BMI range for overall health. The rising prevalence of class III obesity is a major public health concern given its disproportionate impact on health, health care utilization and costs. Obesity management is key to preventing the reduction in HRQoL associated with obesity-related comorbidities, and this analysis supports the development of targeted policies and population health initiatives for people with class III obesity.

Emerging costs in a "hidden" workforce: The longitudinal psychosocial effects of caregiving during the COVID-19 pandemic among Norwegian adults.

During COVID-19 many informal caregivers experienced increased caregiving load while access to formal and informal support systems and coping resources decreased. Little is known about the psychosocial costs of these challenges for an essential yet vulnerable and "hidden" frontline workforce. This study explores and compares changes in psychosocial well-being (psychological well-being, psychological ill-being, and loneliness) before and across up to three stages of the COVID-19 pandemic among caregivers and non-caregivers. We also examine predictors of psychosocial well-being among caregivers during the peak of the pandemic. We use longitudinal data collected online in the Norwegian Counties Public Health Survey (age: 18-92) in four counties and up to four data points (n = 14,881). Caregivers are those who provide care unpaid, continuous (≥ monthly across all time points) help to someone with health problems. Findings show that levels of psychosocial well-being first remained stable but later, during the peak stages of the pandemic, dropped markedly. Caregivers (13-15% of the samples) report lower psychosocial well-being than non-caregivers both before and during the pandemic. Caregivers seem especially vulnerable in terms of ill-being, and during the peak of the pandemic caregivers report higher net levels of worry (OR = 1.22, p < 0.01) and anxiety (OR = 1.23, p < 0.01) than non-caregivers. As expected, impacts are graver for caregivers who provide more intensive care and those reporting health problems or poor access to social support. Our study findings are valuable information for interventions to support caregivers during this and future pandemics.

Built Environment Accessibility and Disability as Predictors of Well-Being among Older Adults: A Norwegian Cross-Sectional Study.

Knowledge about the influence environmental factors have on well-being is important to deliver policies supporting healthy ageing and sustainable health equity. An under-researched question is whether and how the built environment plays a role on well-being among older adults with disabilities. This study explores the relationship between built environment accessibility and disability on psychosocial well-being among older adults. Data were used from the Norwegian Counties Public Health Survey collected during February 2021 in Møre and Romsdal county (N = 8274; age = 60-97, mean = 68.6). General linear modelling was performed to examine the relationship and interaction between built environment accessibility (services, transportation, and nature) and disability on psychosocial well-being (quality of life, thriving, loneliness, and psychological distress). Higher levels of disability and poorer accessibility were each significantly related to lower psychosocial well-being across all variables (p < 0.001). Significant interaction effects were observed between disability and built environment accessibility on thriving (F(8, 5936) = 4.97, p < 0.001, η2 = 0.006) and psychological distress (F(8, 5957) = 3.09, p = 0.002, η2 = 0.004). No significant interaction effects were found for quality of life and loneliness. These findings indicate good built environment accessibility is associated with thriving and reduces psychological distress among older adults with disabilities. This study supports and extends previous findings on the importance of accessible and equipped environments for well-being and may aid policy makers when planning built environments to foster healthy ageing among this population group.

The improved health utility of once-weekly subcutaneous semaglutide 2.4 mg compared with placebo in the STEP 1-4 obesity trials.

AIM: To assess health utility values in the Semaglutide Treatment Effect in People with obesity (STEP) 1-4 trials. MATERIALS AND METHODS: The STEP 1-4 phase 3a, 68-week, double-blind randomized controlled trials assessed the efficacy and safety of semaglutide 2.4 mg versus placebo in individuals with a body mass index (BMI) of 30 kg/m2 or higher or a BMI of 27 kg/m2 or higher and at least one comorbidity (STEP 1, 3 and 4), or a BMI of 27 kg/m2 or higher and type 2 diabetes (STEP 2). Patients received lifestyle intervention plus intensive behavioural therapy in STEP 3. Health-related quality of life was assessed using the Short Form 36-item Health Survey version 2 (SF-36v2) at baseline and week 68. Scores were converted into Short Form Six-Dimension version 2 (SF-6Dv2) utility scores or mapped onto the European Quality of Life Five-Dimension Three-Level (EQ-5D-3L) utility index using UK health utility weights. RESULTS: At week 68, semaglutide 2.4 mg was associated with minor health utility score improvements from baseline (all trials), while scores for placebo typically decreased. SF-6Dv2 treatment differences by week 68 for semaglutide 2.4 mg versus placebo were significant in STEP 1 and 4 (P ≤ .001), but not STEP 2 or 3. EQ-5D-3L treatment differences by week 68 for semaglutide 2.4 mg versus placebo were significant in STEP 1, 2 and 4 (P < .001 for all), but not STEP 3. CONCLUSIONS: Semaglutide 2.4 mg was associated with improvement in health utility scores compared with placebo, reaching statistical significance in STEP 1, 2 and 4.

Combinatorial batching of DNA for ultralow-cost detection of pathogenic variants.

BACKGROUND: Next-generation sequencing (NGS) based population screening holds great promise for disease prevention and earlier diagnosis, but the costs associated with screening millions of humans remain prohibitive. New methods for population genetic testing that lower the costs of NGS without compromising diagnostic power are needed. METHODS: We developed double batched sequencing where DNA samples are batch-sequenced twice - directly pinpointing individuals with rare variants. We sequenced batches of at-birth blood spot DNA using a commercial 113-gene panel in an explorative (n = 100) and a validation (n = 100) cohort of children who went on to develop pediatric cancers. All results were benchmarked against individual whole genome sequencing data. RESULTS: We demonstrated fully replicable detection of cancer-causing germline variants, with positive and negative predictive values of 100% (95% CI, 0.91-1.00 and 95% CI, 0.98-1.00, respectively). Pathogenic and clinically actionable variants were detected in RB1, TP53, BRCA2, APC, and 19 other genes. Analyses of larger batches indicated that our approach is highly scalable, yielding more than 95% cost reduction or less than 3 cents per gene screened for rare disease-causing mutations. We also show that double batched sequencing could cost-effectively prevent childhood cancer deaths through broad genomic testing. CONCLUSIONS: Our ultracheap genetic diagnostic method, which uses existing sequencing hardware and standard newborn blood spots, should readily open up opportunities for population-wide risk stratification using genetic screening across many fields of clinical genetics and genomics.

Exclusion from Social Relations in Later Life: Micro- and Macro-Level Patterns and Correlations in a European Perspective.

Older adults face particular risks of exclusion from social relationships (ESR) and are especially vulnerable to its consequences. However, research so far has been limited to specific dimensions, countries, and time points. In this paper, we examine the prevalence and micro- and macro-level predictors of ESR among older adults (60+) using two waves of data obtained four years apart across 14 European countries in the Survey of Health, Ageing and Retirement in Europe (SHARE). We consider four ESR indicators (household composition, social networks, social opportunities, and loneliness) and link them to micro-level (age, gender, socioeconomic factors, health, and family responsibilities) and national macro-level factors (social expenditures, unmet health needs, individualism, social trust, and institutional trust). Findings reveal a northwest to southeast gradient, with the lowest rates of ESR in the stronger welfare states of Northwest Europe. The high rates of ESR in the southeast are especially pronounced among women. Predictably, higher age and fewer personal resources (socioeconomic factors and health) increase the risk of all ESR dimensions for both genders. Macro-level factors show significant associations with ESR beyond the effect of micro-level factors, suggesting that national policies and cultural and structural characteristics may play a role in fostering sociability and connectivity and, thus, reduce the risk of ESR in later life.

Quantitative assessment of observed versus predicted responses to selection.

Although artificial-selection experiments seem well suited to testing our ability to predict evolution, the correspondence between predicted and observed responses is often ambiguous due to the lack of uncertainty estimates. We present equations for assessing prediction error in direct and indirect responses to selection that integrate uncertainty in genetic parameters used for prediction and sampling effects during selection. Using these, we analyzed a selection experiment on floral traits replicated in two taxa of the Dalechampia scandens (Euphorbiaceae) species complex for which G-matrices were obtained from a diallel breeding design. After four episodes of bidirectional selection, direct and indirect responses remained within wide prediction intervals, but appeared different from the predictions. Combined analyses with structural-equation models confirmed that responses were asymmetrical and lower than predicted in both species. We show that genetic drift is likely to be a dominant source of uncertainty in typically-dimensioned selection experiments in plants and a major obstacle to predicting short-term evolutionary trajectories.

Locked and lonely? A longitudinal assessment of loneliness before and during the COVID-19 pandemic in Norway.

AIMS: There are concerns that lockdown measures taken during the current COVID-19 pandemic lead to a rise in loneliness, especially in vulnerable groups. We explore trends in loneliness before and during the pandemic and differences across population subgroups. METHODS: Data were collected via online questionnaires in June 2020 and four to eight months prior in two Norwegian counties (N=10,740; 54% women; age 19-92 years). Baseline data come from the Norwegian Counties Public Health Survey (participation rate 46%, of which 59% took part in a COVID-19 follow-up study). RESULTS: Overall loneliness was stable or falling during the lockdown. However, some subgroups, single individuals and older women, reported slightly increased loneliness during lockdown. Interestingly, individuals with low social support and high levels of psychological distress and loneliness before the pandemic experienced decreasing loneliness during the pandemic. CONCLUSIONS: Although data limitations preclude strong conclusions, our findings suggest that, overall, Norwegians seem to have managed the lockdown without alarming increases in loneliness. It is important to provide support and to continue investigating the psychological impact of the pandemic over time and across regions differentially affected by the pandemic.

Development of loneliness in midlife and old age: Its nature and correlates.

Research has long demonstrated that loneliness is a key risk factor for poor health. However, less is known about the development and predictors of loneliness across later adulthood. We examined these questions using two-wave data obtained 5 years apart in the population-based Norwegian NorLAG study (N = 5,555; age 40-80 years; 51% women). We considered direct measures of loneliness (asking directly about feeling lonely) and indirect measures (avoiding the term loneliness) and linked them to self-report data on personality and contact with friends, and to register data on socioeconomic (education, income, unemployment), physical health (sick leave, lifetime history of disability), and social factors (children, marriage/cohabitation, lifetime history of divorce and widowhood). Results indicated that levels of loneliness increased steadily for women, whereas men's levels followed a U-shaped curve, with highest loneliness at ages 40 and 80. At age 40, loneliness declined between the two data waves, but with increasing age the decrease abated and turned into increases when loneliness was measured indirectly. Disability, no spouse/cohabiting partner, widowhood, and little contact with friends were each associated with more loneliness. Similarly, people high in emotional stability and extraversion reported less loneliness and experienced steeper loneliness declines on one or both loneliness measures. We take our results to illustrate the utility of combining self-report and register data and conclude that the development of loneliness across the second half of life is associated with both individual difference characteristics and aspects of social embedding. We discuss possible mechanisms underlying our findings and consider practical implications. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

A hidden Markov model for describing turbostratic disorder applied to carbon blacks and graphene.

A mathematical framework is presented to represent turbostratic disorder in materials like carbon blacks, smectites and twisted n-layer graphene. In particular, the set of all possible disordered layers, including rotated, shifted and curved layers, forms a stochastic sequence governed by a hidden Markov model. The probability distribution over the set of layer types is treated as an element of a Hilbert space and, using the tools of Fourier analysis and functional analysis, expressions are developed for the scattering cross sections of a broad class of disordered materials.

Evaluating the efficacy of Seattle-PAP for the respiratory support of premature neonates: study protocol for a randomized controlled trial.

BACKGROUND: At birth, the majority of neonates born at <30 weeks of gestation require respiratory support to facilitate transition and ensure adequate gas exchange. Although the optimal approach to the initial respiratory management is uncertain, the American Academy of Pediatrics endorses noninvasive respiratory support with nasal continuous positive airway pressure (nCPAP) for premature neonates with respiratory insufficiency. Despite evidence for its use, nCPAP failure, requiring intubation and mechanical ventilation, is common. Recently, investigators have described a novel method to deliver bubble nCPAP, termed Seattle-PAP. While preclinical and pilot studies are encouraging regarding the potential value of Seattle-PAP, a large trial is needed to compare Seattle-PAP directly with the current standard of care for bubble nCPAP (Fisher & Paykel CPAP or FP-CPAP). METHODS/DESIGN: We designed a multicenter, non-blinded, randomized controlled trial that will enroll 230 premature infants (220/7 to 296/7 weeks of gestation). Infants will be randomized to receive Seattle-PAP or FP-CPAP. The primary outcome is respiratory failure requiring intubation and mechanical ventilation. Secondary outcomes include measures of short- and long-term respiratory morbidity and cost-effectiveness. DISCUSSION: This trial will assess whether Seattle-PAP is more efficacious and cost-effective than FP-CPAP in real-world practice among premature neonates. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03085329 . Registered on 21 March 2017.

Self-esteem across the second half of life: The role of socioeconomic status, physical health, social relationships, and personality factors.

Self-esteem development across adulthood has been in the center of interest for some time now. However, not much is known about factors that shape self-esteem and its development in the second half of life and whether the factors differ with age and gender. To examine these questions, this study uses 2-wave data from the population-based NorLAG study in Norway (N = 5,555; Mage = 58 years; 51% women) and combines self-report data on self-esteem and personality with registry-based information on socioeconomic status (education, income, unemployment), health problems (sick leave, lifetime history of disability), and social relationships (cohabiting partner, lifetime history of divorce and widowhood). Results from latent change score models revealed that self-esteem peaked at around age 50 and declined thereafter. More importantly, lower socioeconomic status, not having a cohabiting partner, unemployment, and disability were each uniquely associated with lower levels of self-esteem and/or steeper declines in self-esteem over the 5-year study period. Over and above registry-based information, personality characteristics were relevant, with a more mature personality being associated with higher self-esteem level. Emotionally stable participants also showed less pronounced declines in self-esteem. Moreover, associations of disability and of emotional stability with self-esteem level were weaker with advancing age. Among women, self-esteem level was more strongly associated with emotional stability and less strongly with openness, compared to men. Our findings demonstrate the utility of registry-based information and suggest that physical health, social relationships, and personality factors are in manifold ways uniquely associated with self-esteem and its development later in life. (PsycINFO Database Record

Value of Myocardial Perfusion Assessment With Coronary Computed Tomography Angiography in Patients With Recent Acute-Onset Chest Pain.

OBJECTIVES: The authors sought to perform a randomized controlled trial to evaluate the clinical efficacy of combined examination with coronary computed tomography angiography (CTA) and computed tomography perfusion imaging (CTP) compared to coronary CTA alone. BACKGROUND: Stress myocardial CTP may increase diagnostic specificity when added to coronary CTA in patients suspected of having ischemic heart disease. METHODS: Patients recently hospitalized for acute-onset chest pain, who had acute coronary syndrome had been ruled out by normal electrocardiograms, normal troponin levels, and relief of symptoms, and who had a clinical indication for outpatient noninvasive testing, were screened for inclusion in the CATCH-2 (CArdiac cT in the treatment of acute CHest pain 2) trial (NCT02014311). Patients were randomized 1:1 to examination with coronary CTA or coronary CTA+CTP. The primary endpoint was the frequency of coronary revascularization among patients referred for invasive coronary angiography (ICA) based on index computed tomography evaluation. Secondary endpoints were invasive procedural complications at index-related ICA, post-index cardiac death, hospital admittance because of recurrence of chest pain, unstable angina pectoris, or acute myocardial infarction, ICA, and revascularization. RESULTS: Among 300 patients allocated to the coronary CTA+CTP group, 41 (14%) were referred for ICA compared with 89 (30%) allocated to coronary CTA (p < 0.0001). The primary endpoint occurred in 50% of coronary CTA+CTP patients versus 48% of invasively examined patients (p = 0.85). The total number of revascularizations was significantly lower in the coronary CTA+CTP group compared to the coronary CTA group (n = 20 [7%] vs. n = 42 [14%]; p = 0.0045). At median follow-up of 1.5 years, the occurrence of secondary endpoints was similar in the 2 groups. CONCLUSIONS: A post-discharge diagnostic strategy of coronary CTA+CTP safely reduces the need for invasive examination and treatment in patients suspected of having ischemic heart disease. (CArdiac cT in the treatment of acute CHest pain 2-Myocardial CT Perfusion [CATCH2]; NCT02014311).

Educational inequalities in late-life depression across Europe: results from the generations and gender survey.

This study explores country- and gender-stratified educational differences in depression among older adults from 10 European countries. We examine inequalities in both absolute (prevalence differences) and relative (odds ratios) terms and in bivariate and multivariate models. We use cross-sectional, nationally representative data from the generations and gender survey. The analysis comprises 27,331 Europeans aged 60-80. Depression is measured with a seven-item version of the Center for Epidemiologic Studies Depression scale. Findings show considerable between-country heterogeneity in late-life depression. An East-West gradient is evident, with rates of depression up to three times higher in Eastern European than in Scandinavian countries. Rates are about twice as high among women than men in all countries. Findings reveal marked absolute educational gaps in depression in all countries, yet the gaps are larger in weaker welfare states. This pattern is less pronounced for the relative inequalities, especially for women. Some countries observe similar relative inequalities but vastly different absolute inequalities. We argue that the absolute differences are more important for social policy development and evaluation. Educational gradients in depression are strongly mediated by individual-level health and financial variables. Socioeconomic variation in late-life depression is greater in countries with poorer economic development and welfare programs.

Genome-wide meta-analysis associates HLA-DQA1/DRB1 and LPA and lifestyle factors with human longevity.

Genomic analysis of longevity offers the potential to illuminate the biology of human aging. Here, using genome-wide association meta-analysis of 606,059 parents' survival, we discover two regions associated with longevity (HLA-DQA1/DRB1 and LPA). We also validate previous suggestions that APOE, CHRNA3/5, CDKN2A/B, SH2B3 and FOXO3A influence longevity. Next we show that giving up smoking, educational attainment, openness to new experience and high-density lipoprotein (HDL) cholesterol levels are most positively genetically correlated with lifespan while susceptibility to coronary artery disease (CAD), cigarettes smoked per day, lung cancer, insulin resistance and body fat are most negatively correlated. We suggest that the effect of education on lifespan is principally mediated through smoking while the effect of obesity appears to act via CAD. Using instrumental variables, we suggest that an increase of one body mass index unit reduces lifespan by 7 months while 1 year of education adds 11 months to expected lifespan.Variability in human longevity is genetically influenced. Using genetic data of parental lifespan, the authors identify associations at HLA-DQA/DRB1 and LPA and find that genetic variants that increase educational attainment have a positive effect on lifespan whereas increasing BMI negatively affects lifespan.

Social pathways to health: On the mediating role of the social network in the relation between socio-economic position and health.

Good health is one of the key qualities of life, but opportunities to be and remain healthy are unequally distributed across socio-economic groups. The beneficial health effects of the social network are well known. However, research on the social network as potential mediator in the pathway from socio-economic position (SEP) to health is scarce, while there are good reasons to expect a socio-economical patterning of networks. We aim to contribute to our understanding of socio-economic inequalities in health by examining the mediating role of structural and functional characteristics of the social network in the SEP-health relationship. Data were from the second wave of the Norwegian study on the life course, aging and generation study (NorLAG) and comprised 4534 men and 4690 women aged between 40 and 81. We applied multiple mediation models to evaluate the relative importance of each network characteristic, and multiple group analysis to examine differences between middle-aged and older men and women. Our results indicated a clear socio-economical patterning of the social network for men and women. People with higher SEP had social networks that better protect against loneliness, which in turn lead to better health outcomes. The explained variance in health in older people by the social network and SEP was only half of the explained variance observed in middle-aged people, suggesting that other factors than SEP were more important for health when people age. We conclude that it is the function of the network, rather than the structure, that counts for health.

Signal honesty and cost of pollinator rewards in Dalechampia scandens (Euphorbiaceae).

BACKGROUND AND AIMS: Most species of Dalechampia vines (Euphorbiaceae) attract bee pollinators with terpenoid resins secreted by a gland-like structure in the inflorescence. In some species, pollinating bees appear to preferentially visit inflorescences (blossoms) with large resin-producing glands, whereas in other species bees preferentially visit blossoms with large involucral bracts. In this study, the reliability of bract and gland size as signals of the quantity of resin produced in one species, D. scandens, was assessed. Whether resin secretion has a cost with respect to the number or mass of the seeds produced by a blossom was also examined. METHODS: Measurements were made of bract size, gland size and the amount of resin secreted by blossoms of D. scandens maintained in a common environment, and the relationships between these traits were analysed. Resin production was also manipulated, and the effects of the manipulation were tested on seed set and seed mass. KEY RESULTS: The amount of resin produced was better predicted by the size of the gland than by the size of the bract. Furthermore, when the effect of gland size was accounted for, bract size only weakly predicted the amount of resin produced. Neither an increase in resin secretion (by daily removal of the resin) nor a decrease (by removal of the resin gland) affected seed set or seed mass detectably, but resin production correlated positively with mean seed mass at the individual level once the size of the resin gland was accounted for. CONCLUSIONS: Gland size is a better indicator of the amount of reward than bract size, although the latter remained an honest signal of the quantity of resin produced. Resin secretion has no detectable cost in terms of seed production, but may be condition dependent, as suggested by a positive correlation with seed mass at the individual level.

A method for detecting IBD regions simultaneously in multiple individuals--with applications to disease genetics.

All individuals in a finite population are related if traced back long enough and will, therefore, share regions of their genomes identical by descent (IBD). Detection of such regions has several important applications-from answering questions about human evolution to locating regions in the human genome containing disease-causing variants. However, IBD regions can be difficult to detect, especially in the common case where no pedigree information is available. In particular, all existing non-pedigree based methods can only infer IBD sharing between two individuals. Here, we present a new Markov Chain Monte Carlo method for detection of IBD regions, which does not rely on any pedigree information. It is based on a probabilistic model applicable to unphased SNP data. It can take inbreeding, allele frequencies, genotyping errors, and genomic distances into account. And most importantly, it can simultaneously infer IBD sharing among multiple individuals. Through simulations, we show that the simultaneous modeling of multiple individuals makes the method more powerful and accurate than several other non-pedigree based methods. We illustrate the potential of the method by applying it to data from individuals with breast and/or ovarian cancer, and show that a known disease-causing mutation can be mapped to a 2.2-Mb region using SNP data from only five seemingly unrelated affected individuals. This would not be possible using classical linkage mapping or association mapping.

Effective gas exchange in paralyzed juvenile rabbits using simple, inexpensive respiratory support devices.

We have developed two devices: a high-amplitude bubble continuous positive airway pressure (HAB-CPAP) and an inexpensive bubble intermittent mandatory ventilator (B-IMV) to test the hypotheses that simple, inexpensive devices can provide gas exchange similar to that of bubble CPAP (B-CPAP) and conventional mechanical ventilation (CMV). Twelve paralyzed juvenile rabbits were intubated, stabilized on CMV, and then switched to CPAP. On identical mean airway pressures (MAPs), animals were unable to maintain pulse oximeter oxygen saturation (SpO2) >80% on conventional B-CPAP, but all animals oxygenated well (97.3 ± 2.1%) on HAB-CPAP. In fact, arterial partial pressures of O2 (Pao2) were higher during HAB-CPAP than during CMV (p = 0.01). After repeated lung lavages, arterial partial pressures of CO2 (Paco2) were lower with B-IMV than with CMV (p < 0.0001), despite identical ventilator settings. In lavaged animals, when HAB-CPAP was compared with CMV at the same MAP and 100% O2, no differences were observed in Pao2, but Paco2 levels were higher with HAB-CPAP (70 ± 7 versus 50 ± 5 mm Hg; p < 0.05). Arterial blood pressures were not impaired by HAB-CPAP or B-IMV. The results confirm that simple inexpensive devices can provide respiratory support in the face of severe lung disease and could extend the use of respiratory support for preterm infants into severely resource-limited settings.

Relatedness mapping and tracts of relatedness for genome-wide data in the presence of linkage disequilibrium.

Estimates of relatedness have several applications such as the identification of relatives or in identifying disease related genes through identity by descent (IBD) mapping. Here we present a new method for identifying IBD tracts among individuals from genome-wide single nucleotide polymorphisms data. We use a continuous time Markov model where the hidden states are the number of alleles shared IBD between pairs of individuals at a given position. In contrast to previous methods, our method accurately accounts for linkage disequilibrium using pairwise haplotype probabilities. The method provides a map of the local relatedness along the genome. We illustrate the potential of the method for mapping disease genes on a real data set, and show that the method has the potential to map causative disease mutations using only a handful of affected individuals. The new IBD mapping method provides considerable improvement in mapping power in natural populations compared to standard association mapping methods.