High level of protection against COVID-19 after two doses of BNT162b2 vaccine in the working age population - first results from a cohort study in Southern Sweden

BACKGROUND

Vaccine effectiveness against COVID-19 needs to be assessed in diverse real-world population settings.

METHODS

A cohort study of 805,741 residents in Skåne county, Southern Sweden, aged 18-64 years, of whom 26,587 received at least one dose of the BNT162b2 vaccine. Incidence rates of COVID-19 were estimated in sex- and age-adjusted analysis and stratified in two-week periods with substantial community spread of the disease.

RESULTS

The estimated vaccine effectiveness in preventing infection ≥7 days after second dose was 86% (95% CI 72-94%) but only 42% (95% CI 14-63%) ≥14 days after a single dose. No difference in vaccine effectiveness was observed between females and males. Having a prior positive test was associated with 91% (95% CI 85-94%) effectiveness against new infection among the unvaccinated.

CONCLUSION

A satisfactory effectiveness of BNT162b2 after the second dose was suggested, but with possibly substantially lower effect before the second dose.

Contact allergy to oxidized linalool and oxidized limonene: Patch testing in consecutive patients with dermatitis

BACKGROUND

Contact allergy to oxidized (ox.) linalool and ox. limonene has been reported to have a high prevalence, raising the question of inclusion into the baseline series. However, several important issues should be clarified and further investigated before inclusion can be warranted.

OBJECTIVES

To report the trends of ox. terpenes allergy in patients with dermatitis, features of the patch test reactions, and clinical characteristics of the patients.

METHODS

A retrospective analysis of 5773 patients was performed. All patients were patch tested with baseline series, individual ingredients of fragrance mix I and II, ox. linalool, and ox. limonene from 2013 to 2020.

RESULTS

The prevalence rates of contact allergy to ox. linalool and ox. limonene were 7.0% and 5.1%, respectively. Significantly increasing trends of contact allergy were observed. More than 95% of contact allergy cases were identified on Day 3/4. Patients with contact allergy to ox. linalool and ox. limonene were significantly younger than those with contact allergy to other fragrances and were predominantly female. Strong reactions were associated with older age and multiple fragrance allergies.

CONCLUSIONS

Contact allergy to ox. linalool and ox. limonene is becoming increasingly important, and findings show intriguing features. More studies concerning the clinical relevance before recommending these substances for screening are required.

Exploring Associations of Housing, Relocation, and Active and Healthy Aging in Sweden: Protocol for a Prospective Longitudinal Mixed Methods Study

Background

While housing and neighborhood features have the potential to impact opportunities for active aging, there is a lack of knowledge related to how older people reason regarding their housing situation and how housing and fulfillment of relocation are associated with active and healthy aging.

Objective

The objectives of Prospective RELOC-AGE are to study housing choices and relocation and explore effects on active and healthy aging among men and women aged 55 years and older in Sweden considering relocation.

Methods

The estimated sample (2800) will include people aged 55 years and older being listed for relocation at either of two housing companies: a local public housing company in Southern Sweden and a national condominium provider. Prospective RELOC-AGE has a 2-level longitudinal mixed methods design and includes quantitative surveys (implemented by a professional survey company) and a telephone interview for baseline data collection in 2021, with follow-ups with the same procedures in 2022 and 2023. The survey and interviews include questions related to present housing and neighborhood, relocation plans and expectations, a range of perspectives on active and healthy aging, and demographics. Linking to national registers will provide additional data on home help and health care use, objective housing, and neighborhood characteristics. To explore what housing attributes older adults considering relocation find important and to what extent when making their decisions on housing, we will develop a discrete choice experiment to be implemented with a subsample of participants. Further, a grounded theory approach will be applied to collect in-depth interview data from participants who have moved to another dwelling, within 6 months of the move. A follow-up interview 12 months later will focus on participants’ deepened experience over time in terms of fulfilled expectations and relocation experiences.

Results

As of submission of this protocol (June 2021), recruitment has commenced with approximately 960 respondents to the survey and ongoing telephone interviews. We anticipate recruitment and data collection based on surveys and interviews to continue during 2021.

Conclusions

Prospective RELOC-AGE has the capacity to generate new policy-relevant knowledge on associations of housing, relocation, and active and healthy aging. Such knowledge is relevant for the development of proactive approaches to housing in old age on the individual, group, and societal levels.

Trial Registration

ClinicalTrials.gov NCT04765696; https://clinicaltrials.gov/ct2/show/NCT04765696

International Registered Report Identifier (IRRID)

DERR1-10.2196/31137

Skin Exposures, Hand Eczema and Facial Skin Disease in Healthcare Workers During the COVID-19 Pandemic: A Cross-sectional Study

The COVID-19 pandemic has led to enhanced hygiene procedures and use of personal protective equipment, but also to increased attention to occupational skin disease in healthcare workers. The occurrence of hand and facial skin disease in > 5,000 Swedish healthcare workers was investigated in a questionnaire survey. Levels of skin exposure related to hygiene procedures and personal protective equipment were recorded. Caring for patients with COVID-19 entailed higher levels of wet work and face mask exposures, and was associated with higher 1-year prevalence of both hand eczema (36%) and facial skin disease (32%) compared with not being directly engaged in COVID-19 care (28% and 22%, respectively). Acne and eczema were the most common facial skin diseases; for both, a dose-dependent association with face mask use was found. Dose-dependent associations could be shown between hand eczema and exposure to soap and gloves, but not to alcohol-based hand disinfectants.

274Early adversity scale for schizophrenia (EAS-SZ) constructed and validated using linked register data

Background

A range of adversities have been implicated as risks for schizophrenia. Adversities often cluster, with synergistic impact, which may vary by age of exposure. We expand on current understanding, and propose a method for ranking combinations of adversities associated with risk of schizophrenia, to derive a risk prediction measure.

Methods

We used prospectively collected data for 430,000 children born 1980–2001 in Western Australia, and their parents. Follow up continued until 2015 using linked State registers, identifying 1,620 children with schizophrenia. Five domains of adversity exposure to age 10 were considered. Using Cox modeling of a 40% training data subset, we categorised adversity exposure by associated rates of schizophrenia. Firstly, for each domain separately, numerous constructs of adversity exposure were screened for independent association with schizophrenia. Those with p < =0.2 were combined, using augmented backwards elimination, to define a minimal domain set of jointly associated constructs. Combination was summarised as the linear predictor corresponding to the optimum Cox model. Secondly, these domain summaries were combined with each other to form a global Cox model, predictive of association with schizophrenia.

Harrell’s Concordance was calculated using a 30% assessment sample which did not overlap with our training sample. Prognostic categories were defined and tested.

Results

Harrell’s Concordance was 0.655. Dose response was observed.

Conclusions

Our scale combines many adversity measures into a single construct. It displays dose response and predicts association considerably above chance.

Key messages

EAS-SZ allows a range of adversity exposure profiles to be ranked according to association with schizophrenia.

A directed acyclic graph for interactions

BACKGROUND

Directed acyclic graphs (DAGs) are of great help when researchers try to understand the nature of causal relationships and the consequences of conditioning on different variables. One fundamental feature of causal relations that has not been incorporated into the standard DAG framework is interaction, i.e. when the effect of one variable (on a chosen scale) depends on the value that another variable is set to. In this paper, we propose a new type of DAG-the interaction DAG (IDAG), which can be used to understand this phenomenon.

METHODS

The IDAG works like any DAG but instead of including a node for the outcome, it includes a node for a causal effect. We introduce concepts such as confounded interaction and total, direct and indirect interaction, showing that these can be depicted in ways analogous to how similar concepts are depicted in standard DAGs. This also allows for conclusions on which treatment interactions to account for empirically. Moreover, since generalizability can be compromised in the presence of underlying interactions, the framework can be used to illustrate threats to generalizability and to identify variables to account for in order to make results valid for the target population.

CONCLUSIONS

The IDAG allows for a both intuitive and stringent way of illustrating interactions. It helps to distinguish between causal and non-causal mechanisms behind effect variation. Conclusions about how to empirically estimate interactions can be drawn-as well as conclusions about how to achieve generalizability in contexts where interest lies in estimating an overall effect.

Reweighting a Swedish health questionnaire survey using extensive population register and self-reported data for assessing and improving the validity of longitudinal associations

Background

In cohorts with voluntary participation, participants may not be representative of the underlying population, leading to distorted estimates. If the relevant sources of selective participation are observed, it is however possible to restore the representativeness by reweighting the sample to resemble the target population. So far, few studies in epidemiology have applied reweighting based on extensive register data on socio-demographics and disease history, or with self-reported data on health and health-related behaviors.

Methods

We examined selective participation at baseline and the first two follow-ups of the Scania Public Health Cohort (SPHC), a survey conducted in Southern Sweden in 1999/2000 (baseline survey; n = 13,581 participants, 58% participation rate), 2005 (first follow-up, n = 10,471), and 2010 (second follow-up; n = 9,026). Survey participants were reweighted to resemble the underlying population with respect to a broad range of socio-demographic, disease, and health-related characteristics, and we assessed how selective participation impacted the validity of associations between self-reported overall health and dimensions of socio-demographics and health.

Results

Participants in the baseline and follow-up surveys were healthier and more likely to be female, born in Sweden, middle-aged, and have higher socioeconomic status. However, the differences were not very large. In turn, reweighting the samples to match the target population had generally small or moderate impacts on associations. Most examined regression coefficients changed by less than 20%, with virtually no changes in the directions of the effects.

Conclusion

Overall, selective participation with respect to the observed factors was not strong enough to substantially alter the associations with self-assessed health. These results are consistent with an interpretation that SPHC has high validity, perhaps reflective of a relatively high participation rate. Since validity must be determined on a case-by-case basis, however, researchers should apply the same method to other health cohorts to assess and potentially improve the validity.

[GFR estimation in children - age-adjusted creatinine makes the adult Lund-Malmö equation applicable in children and facilitates automatic GFR reporting from the clinical laboratory]

Age-adjustment of creatinine, i.e. recalculation of childhood levels of creatinine to corresponding levels at 18 years of age and applied in the adult revised Lund-Malmö GFR equation led to markedly improved accuracy in Swedish children (n=1 718) at measured GFR <75 mL/min/1.73 m2 (n=318) and preserved high accuracy at ≥75 mL/min/1.73 m2 (n=1 400). The adjusted LMR equation performed as well as dedicated paediatric equations based on height. The proposed adjustment strategy has four strengths: (i) the original coefficients of the adult GFR equation can be used, (ii) the same equation can be used across the entire lifespan without artificial changes in estimated GFR when switching from paediatric to adult care, (iii) the lack of height factor makes it easier to automatically report estimated GFR by the laboratories and (iv) age-adjusted creatinine values imply that well-established creatinine reference intervals for adults can also be used for children.

Child-Centred Health Dialogue for primary prevention of obesity in Child Health Services - a feasibility study

Aims: The aim of this study was to test a Child-Centred Health Dialogue model for primary prevention of obesity for 4-year-old children in Child Health Services, for its feasibility and the responsiveness of its outcomes. Methods: A feasibility study was set up with a non-randomised quasi-experimental cluster design comparing usual care with a structured multicomponent Child-Centred Health Dialogue consisting of two parts: (1) a universal part directed to all children and (2) a targeted part for families where the child is identified with overweight. Results: In total, 203 children participated in Child-Centred Health Dialogue while 582 children received usual care. Nurses trained in the model were able to execute both the universal health dialogue and the targeted part of the intervention. Tutorship enabled the nurses to reflect on and discuss their experiences, which strengthened their confidence and security. One year after the intervention fewer normal-weight 4-year-olds in the intervention group had developed overweight at the age of five compared with the control group, and none had developed obesity. The difference in overweight prevalence at follow-up did not reach statistical significance. Conclusions: This study demonstrates that a child-centred, multicomponent, interactive intervention for the promotion of healthy lifestyles and primary prevention of obesity for all 4-year-old children participating in Child Health Services is feasible on a small scale. As almost all caregivers make use of Child Health Services in Sweden, the findings should be confirmed in a randomised controlled trial before the intervention can be implemented on a larger scale.

Impact of winter holiday and government responses on mortality in Europe during the first wave of the COVID-19 pandemic

Background

This aggregated population study investigated the impact of the seemingly quasi-randomly assigned school winter holiday in weeks 6–10 (February to early March) on excess mortality in 219 European regions (11 countries) during the COVID-19 pandemic in the spring 2020. A secondary aim was to evaluate the impact of government responses to the early inflow of infected cases.

Methods

Data on government responses weeks 8–14 were obtained from the Oxford COVID-19 Government Response Tracker. Regional data on total all-cause mortality during weeks 14–23 in 2020 were retrieved from Eurostat and national statistical agencies and compared with the average mortality during same period 2015–2019. Variance-weighted least square regression was used with mortality difference as dependent variable with adjustment for country, population density and age distribution.

Results

Being a region with winter holiday exclusively in week 9 was in the adjusted analysis associated with 16 weekly excess deaths [95% confidence interval (CI) 13–20] per million inhabitants during weeks 14–23, which corresponds to 38% of the excess mortality in these regions. A more stringent response implemented in week 11, corresponding to 10 additional units on the 0–100 ordinal scale, was associated with 20 fewer weekly deaths (95% CI 18–22) per million inhabitants.

Conclusions

Winter holiday in week 9 was an amplifying event that contributed importantly to the excess mortality observed in the study regions during the spring 2020. Timely government responses to the resulting early inflow of cases reduced the excess in mortality.

Structure-activity correlation of Ti2CT2MXenes for C-H activation

As a bourgeoning class of 2D materials, MXenes have recently attracted significant attention within heterogeneous catalysis for promoting reactions such as hydrogen evolution and C-H activation. However, the catalytic activity of MXenes is highly dependent on the structural configuration including termination groups and their distribution. Therefore, understanding the relation between the structure and the activity is desired for the rational design of MXenes as high-efficient catalysts. Here, we present that the correlation between the structure and activity of Ti₂CT₂(T is a combination of O, OH and/or F) MXenes for C-H activation can be linked by a quantitative descriptor: the hydrogen affinity (E_H). A linear correlation is observed between the mean hydrogen affinity and the overall ratio of O terminations (x_O) in Ti₂CT₂MXenes, in which hydrogen affinity increases as thex_Odecreases, regardless to the species of termination groups. In addition, the hydrogen affinity is more sensitive to the presence of OH termination than F terminations. Moreover, the linear correlation between the hydrogen affinity and the activity of Ti₂CT₂MXenes for C-H activation of both -CH₃and -CH₂- groups can be extended to be valid for all three possible termination groups. Such a correlation provides fast prediction of the activity of general Ti₂CT₂MXenes, avoiding tedious activation energy calculations. We anticipate that the findings have the potential to accelerate the development of MXenes for heterogeneous catalysis applications.

Machine learning compared with rule-in/rule-out algorithms and logistic regression to predict acute myocardial infarction based on troponin T concentrations

OBJECTIVE

Computerized decision-support tools may improve diagnosis of acute myocardial infarction (AMI) among patients presenting with chest pain at the emergency department (ED). The primary aim was to assess the predictive accuracy of machine learning algorithms based on paired high-sensitivity cardiac troponin T (hs-cTnT) concentrations with varying sampling times, age, and sex in order to rule in or out AMI.

METHODS

In this register-based, cross-sectional diagnostic study conducted retrospectively based on 5695 chest pain patients at 2 hospitals in Sweden 2013-2014 we used 5-fold cross-validation 200 times in order to compare the performance of an artificial neural network (ANN) with European guideline-recommended 0/1- and 0/3-hour algorithms for hs-cTnT and with logistic regression without interaction terms. Primary outcome was the size of the intermediate risk group where AMI could not be ruled in or out, while holding the sensitivity (rule-out) and specificity (rule-in) constant across models.

RESULTS

ANN and logistic regression had similar (95%) areas under the receiver operating characteristics curve. In patients (n = 4171) where the timing requirements (0/1 or 0/3 hour) for the sampling were met, using ANN led to a relative decrease of 9.2% (95% confidence interval 4.4% to 13.8%; from 24.5% to 22.2% of all tested patients) in the size of the intermediate group compared to the recommended algorithms. By contrast, using logistic regression did not substantially decrease the size of the intermediate group.

CONCLUSION

Machine learning algorithms allow for flexibility in sampling and have the potential to improve risk assessment among chest pain patients at the ED.

A Nationwide Cohort Study of Outcome after Pediatric Appendicitis

INTRODUCTION

 Children with appendicitis often present with complicated disease. The aim of this study was to describe the clinical management of pediatric appendicitis, and to report how disease severity and operative modality are associated with short- and long-term risks of adverse outcome.

MATERIALS AND METHODS

 A nationwide retrospective cohort study of all Swedish children (<18 years) diagnosed with appendicitis, 2001 to 2014 (n = 38,939). Primary and secondary outcomes were length of stay, surgical site infections, readmissions, 30-day mortality, and long-term risk of surgery for small bowel obstruction (SBO). Implications of complicated disease and operative modality were assessed with adjustment for age, gender, and trends over time.

RESULTS

 Complicated appendicitis was associated with longer hospital stay (4 vs. 2 days, p < 0.001), increased risk of surgical site infection (5.9 vs. 2.3%, adjusted odds ratio [aOR]: 2.64 [95% confidence interval, CI: 2.18-3.18], p < 0.001), readmission (5.5 vs. 1.2, aOR: 4.74 [95% CI: 4.08-5.53], p < 0.001), as well as long-term risk of surgery for SBO (0.7 vs. 0.2%, adjusted hazard ratio [aHR]: 3.89 [95% CI: 2.61-5.78], p < 0.001). Intended laparoscopic approach was associated with reduced risk of surgical site infections (2.3 vs. 3.1%, aOR: 0.74 [95% CI: 0.62-0.89], p = 0.001), but no overall reduction in risk for SBO; however, successful laparoscopic appendectomy was associated with less SBO during follow-up compared with open appendectomy (aHR: 0.27 [95% CI: 0.11-0.63], p = 0.002).

CONCLUSION

 Children treated for complicated appendicitis are at risk of substantial short- and long-term morbidities. Fewer surgical site infections were seen after intended laparoscopic appendectomy, compared with open appendectomy, also when converted procedures were accounted for.

Development and Validation of a Modified Full Age Spectrum Creatinine-Based Equation to Estimate Glomerular Filtration Rate : A Cross-sectional Analysis of Pooled Data

BACKGROUND

The Chronic Kidney Disease in Children Study (CKiD) equation for children and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation for adults are recommended serum creatinine (SCr)-based calculations for estimating glomerular filtration rate (GFR). However, these equations, as well as their combination, have limitations, notably the problem of implausible changes in GFR during the transition from adolescence to adulthood and overestimation of GFR in young adults. The full age spectrum (FAS) equation addresses these issues but overestimates GFR when SCr levels are low.

OBJECTIVE

To develop and validate a modified FAS SCr-based equation combining design features of the FAS and CKD-EPI equations.

DESIGN

Cross-sectional analysis with separate pooled data sets for development and validation.

SETTING

Research and clinical studies (n = 13) with measured GFR available.

PATIENTS

11 251 participants in 7 studies (development and internal validation data sets) and 8378 participants in 6 studies (external validation data set).

MEASUREMENTS

Clearance of an exogenous marker (reference method), SCr level, age, sex, and height were used to develop a new equation to estimate GFR.

RESULTS

The new European Kidney Function Consortium (EKFC) equation is a FAS equation with low bias (-1.2 mL/min/1.73 m² [95% CI, -2.7 to 0.0 mL/min/1.73 m²] in children and -0.9 mL/min/1.73 m² [CI, -1.2 to -0.5 mL/min/1.73 m²] in adults) across the FAS (2 to 90 years) and SCr range (40 to 490 µmol/L [0.45 to 5.54 mg/dL]) and with fewer estimation errors exceeding 30% (6.5% [CI, 3.8% to 9.1%] in children and 3.1% [CI, 2.5% to 3.6%] in adults) compared with the CKiD and CKD-EPI equations.

LIMITATION

No Black patients were included.

CONCLUSION

The new EKFC equation shows improved accuracy and precision compared with commonly used equations for estimating GFR from SCr levels.

PRIMARY FUNDING SOURCE

Swedish Research Council (Vetenskapsrådet).

Can the validity of a cohort be improved by reweighting based on register data? Evidence from the Swedish MDC study

Background

In any study with voluntary participation, self-selection risks leading to invalid conclusions. If the determinants of selection are observed, it is however possible to restore the parameters of interest by reweighting the sample to match the population, but this approach has seldom been applied in epidemiological research.

Methods

We reweighted the Malmö Diet and Cancer (MDC) study based on population register data on background variables, including socio-demographics and hospital admissions for both participants and the background population. Following individuals from baseline in 1991–1996 and at most until 2016, we studied mortality (all-cause, cancer, and CVD), incidences (cancer and CVD), and associations between these outcomes and background variables. Results from the unweighted and reweighted participant sample were compared with those from the background population.

Results

Mortality was substantially lower in participants than in the background population, but reweighting the sample helped only little to make the numbers similar to those in the background population. For incidences and associations, numbers were generally similar between participants and the background population already without reweighting, rendering reweighting unnecessary.

Conclusion

Reweighting samples based on an extensive range of sociodemographic characteristics and previous hospitalizations does not necessarily yield results that are valid for the population as a whole. In the case of MDC, there appear to be important factors related to both mortality and selection into the study that are not observable in registry data, making it difficult to obtain accurate numbers on population mortality based on cohort participants. These issues seem less relevant for incidences and associations, however. Overall, our results suggest that representativeness must be judged on a case-by-case basis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-10004-z.

Association of coronary calcium score with endothelial dysfunction and arterial stiffness

BACKGROUND AND AIMS

The aim of the study was to determine potential associations between endothelial dysfunction and arterial stiffness, measured by peripheral arterial tonometry, and coronary artery calcium score (CACS) assessed by computed tomography (CT).

METHODS AND RESULTS

The BIG3 study is a prospective longitudinal, non-interventional, pulmonary-cardiovascular cohort study exploring the three major smoking-induced diseases: cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer, in a 45-75 aged cohort (mean 62 years), enriched in smokers. Computed tomography of the chest with assessment of CACS was performed in a selected subset of the participants (n = 2080). Peripheral arterial tonometry (EndoPAT) was used to assess endothelial function and arterial stiffness measured as reactive hyperaemia index (RHI) and augmentation index (AI), respectively. We observed significant associations of CACS, endothelial dysfunction, and arterial stiffness with several risk factors for coronary heart disease including age, sex, BMI, diabetes mellitus, and blood pressure. There was significant association of CACS, classified into three levels of severity, with RHI and AI (p = 0.0005 and p = 0.0009, respectively). For groups of increasing CACS (0, 1-400 and > 400 Agatston score), RHI decreased from median 1.89 (1.58-2.39), and 1.93 (1.62-2.41) to 1.77 (1.51-2.10). AI increased from median 14.3 (5.7-25.2), and 16.4 (8.1-27.6) to 18.0 (9.1-29.2). RHI, but not AI, remained significantly associated with CACS after risk factors adjustment.

CONCLUSIONS

In this large study of coronary artery calcium and vascular function, we found an association between CACS and both endothelial dysfunction and arterial stiffness, indicating that they may reflect similar mechanisms for development of cardiovascular disease.

How boys and testicles wander to surgery: a nationwide cohort study of surgical delay in Sweden

BACKGROUND

Early orchidopexy is recommended for cryptorchidism and the surgery is increasingly centralised. The objectives were to determine the incidence, risk factors and if distance to treating hospital impacted on timely treatment of cryptorchidism.

METHODS

In this observational study, all boys born in Sweden from 2001 to 2014 were followed in national registers to determine the incidence of cryptorchidism by levels of birth-related risk factors and social determinants. Travel time to hospital was used as the primary exposure in multivariable survival analysis, with age at surgery as main outcome.

RESULTS

Of 748 678 boys at risk for cryptorchidism, 7351 were treated and evaluated for timing of surgery (cumulative childhood incidence 1.4%, 95% CI 1.3% to 1.5%). The incidence was clearly associated with prematurity and overdue pregnancy (HR for <32 weeks 2.77 (95% CI 2.39 to 3.21); 32-36 weeks HR 1.36 (95% CI 1.24 to 1.49); >41 weeks HR 1.19 (95% CI 1.10 to 1.29)), low birth weight (<1000 g HR 3.94 (95% CI 3.15 to 4.92); 1000-1499 g HR 3.70 (95% CI 3.07 to 4.46); 1500-2500 g HR 1.69 (95% CI 1.52 to 1.88)) and intrauterine growth restriction (small for gestational age HR 2.38 (95% CI 2.14 to 2.65); large for gestational age HR 1.26 (95% CI 1.13 to 1.42)), but not with smoking or maternal age. Each 30 min increase in travel time was associated with a reduced probability of timely treatment (HR for being treated by age 3 adjusted for risk factors and socioeconomic determinants: 0.91 (95% CI 0.88 to 0.95)). Lower income and financial support were also associated with treatment delays (adjusted HR for lowest income quintile 0.82 (95% CI 0.72 to 0.93) and for families with financial support 0.85 (95% CI 0.73 to 0.97)).

CONCLUSIONS

Travel distance to treating hospital was associated with delayed treatment. 'Not all those who wander are lost', but these findings suggest a trade-off between centralisation benefits and barriers of geography also in elective paediatric surgery.

The impact of occupational and personal factors on musculoskeletal pain - a cohort study of female nurses, sonographers and teachers

Background

Musculoskeletal pain is common in the general population and constitutes a major public health problem. A large proportion of these conditions may be work related. The aim of this study was to explore the relative importance of physical, psychosocial and personal factors, in number of pain sites and in five specific pain sites, among women in common professions with a broad variety of occupational exposures.

Methods

A cohort of 1115 women responded to a questionnaire on ergonomic, psychosocial, personal and life-style factors, and the outcome measure of musculoskeletal pain (based on frequency and intensity of complaints at nine anatomical sites), at baseline and at follow-up. Sum scores of ergonomic and psychosocial factors were created. The importance of exposure at baseline for the number of pain sites at follow-up were estimated using ordinal regression. The importance of exposure at baseline for pain in the neck, shoulders, hands, lower back and feet at follow-up were estimated using multi-exposure Poisson regression models.

Results

High sum scores for ergonomic and psychosocial factors were of importance for a high number of pain sites, although the strongest risk factor was a high number of pain sites already at baseline. On the individual level, there was a large fluctuation in number of pain sites between the two time points. Eighteen percent reported persistent (or recurrent) ≥ four pain sites, while only 11 % did not report any pain at baseline or at follow-up. Among the specific pain sites, a high sum score of ergonomic factors was associated with pain in the neck, hands and feet. A high sum score of psychosocial factors was associated with neck and shoulder pain. The strongest risk factor was, however, pain at that specific anatomical site at baseline. Only a few of the personal and life-style factors were associated with pain.

Conclusions

An overwhelming majority of the women in common occupations were affected by musculoskeletal pain. Both ergonomic and psychosocial factors were predictive of a high number of pain sites and of specific pain sites. These findings indicate the need for preventive measures on the individual, organizational and societal level.

C-H activation of light alkanes on MXenes predicted by hydrogen affinity

C-H activation of light alkanes is one of the most important reactions for a plethora of applications but requires catalysts to operate at feasible conditions. MXenes, a new group of two-dimensional materials, have shown great promise as heterogeneous catalysts for several applications. However, the catalytic activity of MXenes depends on the type and distribution of termination groups. Theoretically, it is desired to search for a relation between the catalytic activity and the termination configuration by employing a simple descriptor in order to avoid tedious activation energy calculations. Here, we show that MXenes are promising for splitting C-H bonds of light alkanes. Furthermore, we present how a quantitative descriptor - the hydrogen affinity - can be used to characterize the termination configuration of Ti₂CT_z (T = O, OH) MXenes, as well as the catalytic activity towards dehydrogenation reactions, using propane as model system. First-principles calculations reveal that the hydrogen affinity can be considered as an intrinsic property of O and OH terminated Ti₂C MXenes, in which the mean hydrogen affinity for the terminated Ti₂C MXenes is linearly correlated to the statistical average of their OH fraction. In addition, the C-H activation energies exhibit a strong scaling relationship to the hydrogen affinity. This quantity can therefore yield quick predictions of catalytic activity of terminated Ti₂C MXenes towards C-H activations, and even predict their chemical selectivity toward scissoring different C-H bonds. We believe that the hydrogen affinity will accelerate the discovery of further applications of the broad family of MXenes in heterogeneous catalysis.

Controlled-Atmosphere Flame Fusion Single-Crystal Growth of Non-Noble fcc, hcp, and bcc Metals Using Copper, Cobalt, and Iron

The growth of noble‐metal single crystals via the flame fusion method was developed in the 1980s. Since then, there have been no major advancements to the technique until the recent development of the controlled‐atmosphere flame fusion (CAFF) method to grow non‐noble Ni single crystals. Herein, we demonstrate the generality of this method with the first preparation of fcc Cu as well as the first hcp and bcc single crystals of Co and Fe, respectively. The high quality of the single crystals was verified using scanning electron microscopy and Laue X‐ray backscattering. Based on Wulff constructions, the equilibrium shapes of the single‐crystal particles were studied, confirming the symmetry of the fcc, hcp, and bcc single‐crystal lattices. The low cost of the CAFF method makes all kinds of high‐quality non‐noble single crystals independent of their lattice accessible for use in electrocatalysis, electrochemistry, surface science, and materials science.

Prospects for improved glomerular filtration rate estimation based on creatinine-results from a transnational multicentre study

BACKGROUND

The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine equation is routinely used to assess renal function but exhibits varying accuracy depending on patient characteristics and clinical presentation. The overall aim of the present study was to assess if and to what extent glomerular filtration rate (GFR) estimation based on creatinine can be improved.

METHODS

In a cross-sectional analysis covering the years 2003-17, CKD-EPI was validated against measured GFR (mGFR; using various tracer methods) in patients with high likelihood of chronic kidney disease (CKD; five CKD cohorts, n = 8365) and in patients with low likelihood of CKD (six community cohorts, n = 6759). Comparisons were made with the Lund-Malmö revised equation (LMR) and the Full Age Spectrum equation.

RESULTS

7In patients aged 18-39 years old, CKD-EPI overestimated GFR with 5.0-16 mL/min/1.73 m2 in median in both cohort types at mGFR levels <120 mL/min/1.73 m2. LMR had greater accuracy than CKD-EPI in the CKD cohorts (P30, the percentage of estimated GFR within 30% of mGFR, 83.5% versus 76.6%). CKD-EPI was generally the most accurate equation in the community cohorts, but all three equations reached P30 above the Kidney Disease Outcomes Quality Initiative benchmark of 90%.

CONCLUSIONS

None of the evaluated equations made optimal use of available data. Prospects for improved GFR estimation procedures based on creatinine exist, particularly in young adults and in settings where patients with suspected or manifest CKD are investigated.