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Declines in mental health among youth in the COVID-19 pandemic have been observed, yet longitudinal studies on how housing may impact these declines are lacking.
Our aim was to determine whether changes in mental health among Danish youth were dependent on their housing conditions.
Young participants from the Danish National Birth Cohort, who had responded to an online questionnaire at 18 years of age, and later during the initial national Danish lockdown, were included. Associations between housing conditions (direct access to outdoor spaces, urbanicity, household density, and household composition) and changes in mental health (mental well-being, quality of life (QoL) and loneliness) were examined in multivariate linear and logistic regression analyses.
We included 7455 participants. Greater decreases in mental well-being were observed for youth with no access to direct outdoor spaces and those living in denser households (mean difference -0.83 [95 % CI -1.19, -0.48], -0.30 [-0.43, -0.18], respectively). Onset of low mental well-being was associated with no access and living alone (odds ratios (OR) 1.68 [1.15, 2.47] and OR 1.47 [1.05, 2.07], respectively). Household density was negatively associated with QoL (mean difference -0.21 [-0.30, -0.12]). Youth living alone experienced more loneliness (OR 2.12 [95 % CI 1.59, 2.82]).
How youth’s mental health changed from before to during lockdown was associated with housing conditions. Among the Danish youth in our study, greater decreases in mental health during lockdown were observed among youth without access to outdoor spaces, living alone, or living in denser households.
Social Anxiety Disorder (SAD) is considered the most prevalent anxiety disorder with the highest disease burden amongst anxiety disorders. Despite available effective treatment with Cognitive Behavioral Therapy, a majority of individuals with SAD do not seek treatment and many drop out when confronted with elements of exposure. Several studies highlight the many advantages virtual reality exposure holds over in vivo exposure. In this study, we investigate the added effect of real-time biofeedback during virtual reality exposure.
The current study is part of a large scale study called VR8. The current study aims to develop and evaluate the feasibility of a VR-biofeedback-intervention for adults with mild to severe social anxiety disorder, before continuing randomized controlled trials.
Data from semi-structured interviews and surveys will be compared to biodata collected during VR exposure. Participants include a minimum of (n=10) patients and (n=10) clinicians from the Mental Health Services in the Region of Southern Denmark. Surveys include questionnaires used for assessment of anxiety symptoms, usability of technology, and presence in the virtual environment. Collected biodata includes heart rate variability and electrodermal activity. Behavioral markers include eye-gaze. The findings will be analyzed and discussed in a mixed methods design.
The study is ongoing. Preliminary results will be available at presentation.
Successful development and implementation of a biofeedback-informed virtual reality exposure intervention may provide increased reach for patients and individuals who would have otherwise not sought- or dropped out of regular treatment, as well as inform the clinician on how to proceed during virtual exposure.
Conflict of interest
Prof. Stephané Bouchard is consultant to and own equity in Cliniques et Développement In Virtuo, which develops virtual environments, and conflicts of interests are managed according to UQO’s conflict of interests policy; however, Cliniques et Développeme
It is widely assumed that people with obesity have several common eating patterns, including breakfast-skipping (1), eating during the night (2) and high fast-food consumption (3). However, differences in individual meal and dietary patterns may be crucial to optimizing obesity treatment. Therefore, we investigated the inter-individual variation in eating patterns, hypothesizing that individuals with obesity show different dietary and meal patterns, and that these associate with self-reported energy intake (rEI) and/or anthropometric measures.
Cross-sectional data from 192 participants (aged 20–55 years) with obesity, including 6 days of weighed food records, were analyzed. Meal patterns and dietary patterns were derived using exploratory hierarchical cluster analysis and k-means cluster analysis, respectively.
Five clear meal patterns were found based on the time-of-day with the highest mean rEI. The daily rEI (mean ± SD kcal) was highest among “midnight-eaters” (2550 ± 550), and significantly (p < 0.05) higher than “dinner-eaters” (2060 ± 550), “lunch-eaters” (2080 ± 520), and “supper-eaters” (2100 ± 460), but not “regular-eaters” (2330 ± 650). Despite differences of up to 490 kcal between meal patterns, there were no significant differences in anthropometric measures or physical activity level (PAL). Four dietary patterns were also found with significant differences in intake of specific food groups, but without significant differences in anthropometry, PAL, or rEI. Our data highlight meal timing as a determinant of individual energy intake in people with obesity. The study supports the importance of considering a person’s specific meal pattern, with possible implications for more person-focused guidelines and targeted advice.
Psychiatric morbidity was measured in a prospective follow-up study of 51 patients admitted to hospital after minor head injury. By means of self report questionnaires (eg General Health Questionnaire (SHQ) and Impact of Event Scale), semistructured interviews and symptom-checklists, it was found that nearly half of the patients suffered considerable discomfort after 1 week. Improvement during the 3 months follow-up was generally poor. Both concussional symptoms and stress response contributed to the compromised well-being as measured by the GHQ, but outcome did not correlate to severity of injury. The GHQ-60 score of 1 week showed a strong positive correlation with outcome after 3 months. The incidence of post-traumatic stress disorder was low.
This study directly compares the effectiveness of aripiprazole once-monthly 400 mg (AOM) and paliperidone palmitate once-monthly (PP) on the validated and symptom-focused Heinrichs-Carpenter Quality-of-Life Scale (QLS) in schizophrenia.
A 28-week, randomized, open-label rater-blinded, head-to-head study (NCT01795547) of AOM and PP in adult patients (18-60 years) needing a change from current oral antipsychotic treatment for any reason. The study comprised oral conversion, initiation of AOM or PP treatment according to labels, and treatment continuation with injections every 4 weeks. The primary endpoint assessed non-inferiority and subsequently superiority on change from baseline to week 28 in QLS total score analyzed using a mixed model for repeated measurements.
Of 295 randomized patients, 100/148 (67.6%) of AOM and 83/147 (56.5%) of PP patients completed 28 weeks of treatment. In treated patients, adverse events (AEs) were the most frequent reason for discontinuation; AOM: 16/144 (11.1%), PP: 27/137 (19.7%). The difference in change from baseline to week 28 on QLS total score was statistically significant (4.67 [95%CI: 0.32;9.02], p=0.036), confirming non-inferiority and establishing superiority of AOM compared to PP. The respective changes were 7.47±1.53 for AOM and 2.80±1.62 for PP. AEs occurring at rates ≥5% in either group in the treatment continuation phase were weight increased (AOM: 12/119 [10.1%]; PP: 17/109 [15.6%]), psychotic disorder (AOM: 3/119 [2.5%]; PP: 6/109 [5.5%]) and insomnia (AOM: 3/119 [2.5%]; PP: 6/109 [5.5%]).
Superior improvements on the clinician-rated QLS and lower rates of all-cause discontinuation suggest greater overall effectiveness for aripiprazole once-monthly vs paliperidone palmitate.
In this paper, we develop the first formal nonparametric test for whether the observation errors in option panels display spatial dependence. The panel consists of options with different strikes and tenors written on a given underlying asset. The asymptotic design is of the infill type—the mesh of the strike grid for the observed options shrinks asymptotically to zero, while the set of observation times and tenors for the option panel remains fixed. We propose a Portmanteau test for the null hypothesis of no spatial autocorrelation in the observation error. The test makes use of the smoothness of the true (unobserved) option price as a function of its strike and is robust to the presence of heteroskedasticity of unknown form in the observation error. A Monte Carlo study shows good finite-sample properties of the developed testing procedure and an empirical application to S&P 500 index option data reveals mild spatial dependence in the observation error, which has been declining in recent years.
Mental trauma may precede persistent changes in a person's mental health in the form of psychosis and dissociation. Presently, there are no subtypes to the diagnosis of PTSD. A psychotic subtype of PTSD has been proposed, and studies show that these patients differ as well in symptoms as biologically from patients with non-psychotic PTSD. Dissociation and psychosis are generally viewed as different phenomena. Where dissociation is understood as a disintegration of the mind, psychosis is viewed as a neurodegenerative disorder on a mainly biological/genetic basis. The delineation of psychotic and dissociative symptoms is not clear however.
Our objective is to clarify, whether psychologists and psychiatrists describe trauma-related changes of consciousness (TCC) differently as dissociative or psychotic. Furthermore, we wish to compare scientific journals, and look for differences in how psychiatrists’ and psychologists’ make use of the terms dissociation and psychosis in relation to TCC.
We aim to investigate whether TCC are interpreted differently among psychiatrists and psychologists.
This study is a systematic critical review of the literature. The databases PubMed, Embase and PsychInfo will be used. Articles involving PTSD with TCC will be included. Studies will be classified as viewing TCC's as either psychotic or dissociative, based on the terms the authors use to describe the observed phenomena.
The results will be presented at the EPA in March 2016 in Madrid.
The study will reveal differences in how psychiatrists and psychologists classify TCC's in PTSD.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Lake Untersee is one of the largest perennially ice-covered lakes in Dronning Maud Land. We investigated the energy and water mass balance of Lake Untersee to understand its state of equilibrium. The thickness of the ice cover is strongly correlated with sublimation rates; variations in sublimation rates across the ice cover are largely determined by wind-driven turbulent heat fluxes and the number of snow-covered days. Lake extent and water level have remained stable for the past 20 years, indicating that the water mass balance is in equilibrium. The lake is damned by the Anuchin Glacier and mass balance calculation suggest that subaqueous melting of terminus ice contributes 40–45% of the annual water budget; since there is no evidence of streams flowing into the lake, the lake must be connected to a groundwater system that contributes 55–60% in order to maintain the lake budget in balance. The groundwater likely flows at a rate of ~8.8 × 10−2 m3 s−1, a reasonable estimate given the range of subglacial water flux in the region. The fate of its well-sealed ice cover is likely tied to changes in wind regime, whereas changes in water budget are more closely linked to the response of surrounding glaciers to climate change.
It has been reported that foetal death follows a seasonal pattern. Influenza virus infection has been postulated as one possible contributor to this seasonal variation. This ecological study explored the temporal association between the influenza activity and the frequency of foetal death. Time series analysis was conducted using weekly influenza-like illness consultation proportions from the Danish sentinel surveillance system and weekly proportions of spontaneous abortions and stillbirths from hospital registers from 1994 to 2009. The association was examined in an autoregressive (AR) integrated (I) moving average (MA) model and subsequently analysed with cross-correlation functions. Our findings confirmed the well-known seasonality in influenza, but also seasonality in spontaneous abortion. No clear pattern of seasonality was found for stillbirths, although the analysis exposed dependency between observations. One final AR integrated MA model was identified for the influenza-like illness (ILI) series. We found no statistically significant relationship between weekly influenza-like illness consultation proportions and weekly spontaneous abortion proportions (five lags: P = 0.52; 11 lags: P = 0.91) or weekly stillbirths (five lags: P = 0.93; 11 lags: P = 0.40). Exposure to circulating influenza during pregnancy was not associated with rates of spontaneous abortions or stillbirths. Seasonal variations in spontaneous abortion were confirmed and this phenomenon needs further investigation.
Lake Untersee is a perennially ice-covered Antarctic lake that consists of two basins. The deepest basin, next to the Anuchin Glacier is aerobic to its maximum depth of 160 m. The shallower basin has a maximum depth of 100 m, is anoxic below 80 m, and is shielded from convective currents. The thermal profile in the anoxic basin is unusual in that the water temperature below 50 m is constant at 4°C but rises to 5°C between 70 m and 80 m depth, then drops to 3.7°C at the bottom. Field measurements were used to conduct a thermal and stability analysis of the anoxic basin. The shape of the thermal maximum implies two discrete locations of energy input, one of 0.11 W m-2 at 71 m depth and one of 0.06 W m-2 at 80 m depth. Heat from microbial activity cannot account for the required amount of energy at either depth. Instead, absorption of solar radiation due to an increase in water opacity at these depths can account for the required energy input. Hence, while microbial metabolism is not an important source of heat, biomass increases opacity in the water column resulting in greater absorption of sunlight.
We develop parametric inference procedures for large panels of noisy option data in a setting, where the underlying process is of pure-jump type, i.e., evolves only through a sequence of jumps. The panel consists of options written on the underlying asset with a (different) set of strikes and maturities available across the observation times. We consider an asymptotic setting in which the cross-sectional dimension of the panel increases to infinity, while the time span remains fixed. The information set is augmented with high-frequency data on the underlying asset. Given a parametric specification for the risk-neutral asset return dynamics, the option prices are nonlinear functions of a time-invariant parameter vector and a time-varying latent state vector (or factors). Furthermore, no-arbitrage restrictions impose a direct link between some of the quantities that may be identified from the return and option data. These include the so-called jump activity index as well as the time-varying jump intensity. We propose penalized least squares estimation in which we minimize the L2 distance between observed and model-implied options. In addition, we penalize for the deviation of the model-implied quantities from their model-free counterparts, obtained from the high-frequency returns. We derive the joint asymptotic distribution of the parameters, factor realizations and high-frequency measures, which is mixed Gaussian. The different components of the parameter and state vector exhibit different rates of convergence, depending on the relative (asymptotic) informativeness of the high-frequency return data and the option panel.
Studies of the association between pre-deployment cognitive ability and post-deployment post-traumatic stress disorder (PTSD) have shown mixed results.
To study the inflence of pre-deployment cognitive ability on PTSD symptoms 6–8 months post-deployment in a large population while controlling for pre-deployment education and deployment-related variables.
Study linking prospective pre-deployment conscription board data with post-deployment self-reported data in 9695 Danish Army personnel deployed to different war zones in 1997–2013. The association between pre-deployment cognitive ability and post-deployment PTSD was investigated using repeated-measure logistic regression models. Two models with cognitive ability score as the main exposure variable were created (model 1 and model 2). Model 1 was only adjusted for pre-deployment variables, while model 2 was adjusted for both pre-deployment and deployment-related variables.
When including only variables recorded pre-deployment (cognitive ability score and educational level) and gender (model 1), all variables predicted post-deployment PTSD. When deployment-related variables were added (model 2), this was no longer the case for cognitive ability score. However, when educational level was removed from the model adjusted for deployment-related variables, the association between cognitive ability and post-deployment PTSD became significant.
Pre-deployment lower cognitive ability did not predict post-deployment PTSD independently of educational level after adjustment for deployment-related variables.
In a longitudinal study including 642 healthy 8–11-year-old Danish children, we investigated associations between vitamin D dependent SNP and serum 25-hydroxyvitamin D (25(OH)D) concentrations across a school year (August–June). Serum 25(OH)D was measured three times for every child, which approximated measurements in three seasons (autumn, winter, spring). Dietary and supplement intake, physical activity, BMI and parathyroid hormone were likewise measured at each time point. In all, eleven SNP in four vitamin D-related genes: Cytochrome P450 subfamily IIR1 (CYP2R1); 7-dehydrocholesterol reductase/nicotinamide adenine dinucleotide synthetase-1(DHCR7/NADSYN1); group-specific complement (GC); and vitamin D receptor were genotyped. We found minor alleles of CYP2R1 rs10500804, and of GC rs4588 and rs7041 to be associated with lower serum 25(OH)D concentrations across the three seasons (all P<0·01), with estimated 25(OH)D differences of −5·8 to −10·6 nmol/l from major to minor alleles homozygosity. In contrast, minor alleles homozygosity of rs10741657 and rs1562902 in CYP2R1 was associated with higher serum 25(OH)D concentrations compared with major alleles homozygosity (all P<0·001). Interestingly, the association between season and serum 25(OH)D concentrations was modified by GC rs7041 (Pinteraction=0·044), observed as absence of increase in serum 25(OH)D from winter to spring among children with minor alleles homozygous genotypes compared with the two other genotypes of rs7041 (P<0·001). Our results suggest that common genetic variants are associated with lower serum 25(OH)D concentrations across a school year. Potentially due to modified serum 25(OH)D response to UVB sunlight exposure. Further confirmation and paediatric studies investigating vitamin D-related health outcomes of these genotypic differences are needed.
We present a combined numerical (particle vortex method) and experimental (soap film tunnel) study of a symmetric foil undergoing prescribed oscillations in a two-dimensional free stream. We explore pure pitching and pure heaving, and contrast these two generic types of kinematics. We compare measurements and simulations when the foil is forced with pitching oscillations, and we find a close correspondence between flow visualisations using thickness variations in the soap film and the numerically determined vortex structures. Numerically, we determine wake maps spanned by oscillation frequency and amplitude, and we find qualitatively similar maps for pitching and heaving. We determine the drag–thrust transition for both pitching and heaving numerically, and we discuss it in relation to changes in wake structure. For heaving with low oscillation frequency and high amplitude, we find that the drag–thrust transition occurs in a parameter region with wakes in which two vortex pairs are formed per oscillation period, in contrast to the common transition scenario in regions with inverted von Kármán wakes.
In unipolar depressed patients participating in trials on antidepressants, we investigated if illness characteristics at baseline could predict conversion to bipolar disorder.
A long-term register-based follow-up study of 290 unipolar depressed patients with a mean age of 50.8 years (SD = 11.9) participating in three randomized trials on antidepressants conducted in the period 1985–1994. The independent effects of explanatory variables were examined by applying Cox regression analyses.
The overall risk of conversion was 20.7%, with a mean follow-up time of 15.2 years per patient. The risk of conversion was associated with an increasing number of previous depressive episodes at baseline, [HR 1.18, 95% CI (1.10–1.26)]. No association with gender, age, age at first depressive episode, duration of baseline episode, subtype of depression or any of the investigated HAM-D subscales included was found.
The patients were followed-up through the Danish Psychiatric Central Research Register, which resulted in inherent limitations such as possible misclassification of outcome.
In a sample of middle-aged hospitalized unipolar depressed patients participating in trials on antidepressants, the risk of conversion was associated with the number of previous depressive episodes. Therefore, this study emphasizes that unipolar depressed patients experiencing a relatively high number of recurrences should be followed more closely, or at least be informed about the possible increased risk of conversion.
Glacier surface mass-balance measurements on Greenland started more than a century ago, but no compilation exists of the observations from the ablation area of the ice sheet and local glaciers. Such data could be used in the evaluation of modelled surface mass balance, or to document changes in glacier melt independently from model output. Here, we present a comprehensive database of Greenland glacier surface mass-balance observations from the ablation area of the ice sheet and local glaciers. The database spans the 123 a from 1892 to 2015, contains a total of ~3000 measurements from 46 sites, and is openly accessible through the PROMICE web portal (http://www.promice.dk). For each measurement we provide X, Y and Z coordinates, starting and ending dates as well as quality flags. We give sources for each entry and for all metadata. Two thirds of the data were collected from grey literature and unpublished archive documents. Roughly 60% of the measurements were performed by the Geological Survey of Denmark and Greenland (GEUS, previously GGU). The data cover all regions of Greenland except for the southernmost part of the east coast, but also emphasize the importance of long-term time series of which there are only two exceeding 20 a. We use the data to analyse uncertainties in point measurements of surface mass balance, as well as to estimate surface mass-balance profiles for most regions of Greenland.