Disease and economic burden increase with systemic lupus erythematosus severity 1 year before and after diagnosis: a real-world cohort study, United States, 2004–2015

ObjectiveTo assess the economic burden of patients with SLE by disease severity in the USA 1 year before and after diagnosis.MethodsPatients aged ≥18 years with a first SLE diagnosis (index date) between January 2005 and December 2014 were identified from administrative commercial claims data linked to electronic medical records (EMRs). Disease severity during the year after diagnosis was classified as mild, moderate, or severe using claims-based algorithms and EMR data. Healthcare resource utilisation (HCRU) and all-cause healthcare costs (2017 US$) were reported for 1 year pre-diagnosis and post-diagnosis. Generalised linear modelling examined all-cause costs over 1 year post-index, adjusting for baseline demographics, clinical characteristics, Charlson Comorbidity Index and 1 year pre-diagnosis costs.ResultsAmong 2227 patients, 26.3% had mild, 51.0% moderate and 22.7% severe SLE. Mean per-patient costs were higher for patients with moderate and severe SLE compared with mild SLE during the year before diagnosis: mild US$12 373, moderate $22 559 and severe US$39 261 (p<0.0001); and 1-year post-diagnosis period: mild US$13 415, moderate US$29 512 and severe US$68 260 (p<0.0001). Leading mean cost drivers were outpatient visits (US$13 566) and hospitalisations (US$10 252). Post-diagnosis inpatient utilisation (≥1 stay) was higher for patients with severe (51.2%) and moderate (22.4%) SLE, compared with mild SLE (12.8%), with longer mean hospital stays: mild 0.47 days, moderate 1.31 days and severe 5.52 days (p<0.0001).ConclusionHCRU and costs increase with disease severity in the year before and after diagnosis; leading cost drivers post-diagnosis were outpatient visits and hospitalisations. Earlier diagnosis and treatment may improve health outcomes and reduce HCRU and costs.

Modelling Road Accident using Poisson regression Models

The objective of this research is to evaluate the safety of multi-lane urban roads in India. In this paper, a generalised linear modelling technique is applied for the analysis of the Indian Highway's road accident. The features of road, speed, and traffic data are analysed in Surat on four-lane urban roads. A novel approach to the model of accident prediction for an urban highway is being proposed to include daily average travel (ADT) and average spot speed (AS). The model was developed as a reliant variable and significant variables such as chain width, intersection no, ADT, AS, as separate variables for accidents per kilometre.. The results of the model provide a better assessment of accidents on a multilateral urban road. Because road accidents are different, statistical models do not adequately capture the characteristics of each section. As a result, the results of Poisson regression were the opposite of these variables. There was also no statistically significant type of traffic control. Significant statistically at level 0.05. Accident locations were assessed by correlating the severity of the accident with different attributes. This investigation will contribute to improving urban road safety.

Modelling MTPL insurance claim events: Can machine learning methods overperform the traditional GLM approach?

Pricing an insurance product covering motor third-party liability is a major challenge for actuaries. Comprehensive statistical modelling and modern computational power are necessary to solve this problem. The generalised linear and additive modelling approaches have been widely used by insurance companies for a long time. Modelling with modern machine learning methods has recently started, but applying them properly with relevant features is a great issue for pricing experts. This study analyses the claim-causing probability by fitting generalised linear modelling, generalised additive modelling, random forest, and neural network models. Several evaluation measures are used to compare these techniques. The best model is a mixture of the base methods. The authors’ hypothesis about the existence of significant interactions between feature variables is proved by the models. A simplified classification and visualisation is performed on the final model, which can support tariff applications later.

Role of attitude in nurses’ responses to requests for assisted dying

Background: Legal assisted dying is a rare event, but as legalisation expands, requests for it will likely increase, and the nurse most often receives the informal, initial request. Objectives: To assess the effects of attitude in interaction with normative and control beliefs on an intention to respond to a request for legal assisted dying. Ethical considerations: The study had the lead author’s institutional ethics approval, and participants were informed that participation was both anonymous and voluntary. Methodology: This was a cross-sectional correlational study of 377 Australian registered nurses who completed an online survey. Generalised linear modelling assessed the effects of independent variables against intended responses to requests for legal assisted dying. Results: Compared to nurses who did not support legal assisted dying, nurses who did had stronger beliefs in patient rights, perceived social expectations to refer the request and stronger control in that intention. Nurses who did not support legal assisted dying had stronger beliefs in ethics of duty to the patient and often held dual intentions to discuss the request with the patient but also held an intention to deflect the request to consideration of alternatives. Discussion: This study advances the international literature by developing quantified models explaining the complexity of nurses’ experiences with requests for an assisted death. Attitude was operationalised in interaction with other beliefs and was identified as the strongest influence on intentions, but significantly moderated by ethical norms. Conclusion: The complex of determinants of those intentions to respond to requests for an assisted death suggests they are not isolated from each other. Nurses might have distinct intentions, but they can also hold multiple intentions even when they prioritise one. These findings present opportunities to prepare nurses in a way that enhances moral resilience in the face of complex moral encounters.

Associations between the number of children, age at childbirths and prevalence of chronic low back pain: the Nord-Trøndelag Health Study

Background Associations between childbirths and subsequent risk of low back pain (LBP) have not been clarified. Changes in sex hormone levels or lumbar posture during pregnancy may have an impact on LBP later in life. The purpose of this study was to explore associations between the number of childbirths, age at childbirths and prevalence of chronic LBP in a general population of women. Methods Data were obtained from the Norwegian community-based Nord-Trøndelag Health Study, HUNT2 (1995–1997). Women aged 20–69 years indicated whether they suffered from chronic LBP, defined as LBP persisting at least 3 months continuously during last year. Information about LBP was collected from 3936 women who had experienced no childbirths, 3143 women who had delivered one child only and 20,584 women who had delivered 2 or more children. Of these, 7339 women reported chronic LBP. The 595 women who were pregnant when information was collected were considered separately, regardless of previous births, with 80 women reporting chronic LBP. Associations with prevalence of chronic LBP were examined by generalised linear modelling with adjustment for potential confounders in a cross-sectional design. Results Women who had delivered one child only showed a higher prevalence of chronic LBP than women with no childbirths (prevalence ratio (PR) 1.11; 95% CI: 1.01–1.22). Among women with one or more childbirths, no overall change in prevalence could be demonstrated with an increasing number of children in analyses adjusted for age at first delivery. In women with at least two childbirths, an age less than 20 years at first childbirth was associated with an increased prevalence of chronic LBP (PR 1.36; 95% CI: 1.25–1.49; compared with age 25–29 years). No association was observed between age at last delivery and chronic LBP. The lowest prevalence of chronic LBP was found among women who were currently pregnant (PR 0.80; 95% CI: 0.63–1.00; compared with women with no childbirths). Conclusions Having experienced at least one childbirth seems to be associated with a higher prevalence of chronic LBP later in life. A young age at first childbirth is also associated with a long-lasting increased prevalence.

Diffusion tensor imaging of the roots of the brachial plexus: a systematic review and meta-analysis of normative values

Purpose Diffusion tensor magnetic resonance imaging (DTI) characterises tissue microstructure and provides proxy measures of myelination, axon diameter, fibre density and organisation. This may be valuable in the assessment of the roots of the brachial plexus in health and disease. Therefore, there is a need to define the normal DTI values. Methods The literature was systematically searched for studies of asymptomatic adults who underwent DTI of the brachial plexus. Participant characteristics, scanning protocols, and measurements of the fractional anisotropy (FA) and mean diffusivity (MD) of each spinal root were extracted by two independent review authors. Generalised linear modelling was used to estimate the effect of experimental conditions on the FA and MD. Meta-analysis of root-level estimates was performed using Cohen’s method with random effects. Results Nine articles, describing 316 adults (1:1 male:female) of mean age 35 years (SD 6) were included. Increments of ten diffusion sensitising gradient directions reduced the mean FA by 0.01 (95% CI 0.01, 0.03). Each year of life reduced the mean MD by 0.03 × 10–3 mm2/s (95% CI 0.01, 0.04). At 3-T, the pooled mean FA of the roots was 0.36 (95% CI 0.34, 0.38; I2 98%). The pooled mean MD of the roots was 1.51 × 10–3 mm2/s (95% CI 1.45, 1.56; I2 99%). Conclusions The FA and MD of the roots of the brachial plexus vary according to experimental conditions and participant factors. We provide summary estimates of the normative values in different conditions which may be valuable to researchers and clinicians alike.

Functional data analysis techniques to improve the generalizability of near-infrared spectral data for monitoring mosquito populations

Near infrared spectroscopy is increasingly being used as an economical method to monitor mosquito vector populations in support of disease control. Despite this rise in popularity, strong geographical variation in spectra has proven an issue for generalising predictions from one location to another. Here, we use a functional data analysis approach—which models spectra as smooth curves rather than as a discrete set of points—to develop a method that is robust to geographic heterogeneity. Specifically, we use a penalised generalised linear modelling framework which includes efficient functional representation of spectra, spectral smoothing and regularisation. To ensure better generalisation of model predictions from one training set to another, we use cross-validation procedures favouring smoother representation of spectra. To illustrate the performance of our approach, we collected spectra for field-caught specimens of Anopheles gambiae complex mosquitoes – the most epidemiologically important vector species on the planet – in two sites in Burkina Faso. Using these spectra, we show how models trained on data from one site can successfully classify morphologically identical sibling species in another site, over 250km away. Whilst we apply our framework to species prediction, our unified statistical framework can, alternatively, handle regression analysis (for example, to determine mosquito age) and other types of multinomial classification (for example, to determine infection status). To make our methods readily available for field entomologists, we have created an open-source R package mlevcm. All data used is publicly also available.

Does diabetes influence the probability of experiencing chronic low back pain? A population-based cohort study: the Nord-Trøndelag Health Study

ObjectiveLow back pain (LBP) is a major problem in modern society and it is important to study possible risk factors for this disorder. People with diabetes are often affected by LBP, but whether diabetes represents a risk factor for LBP has not been studied in detail. The aim of this study was to explore the association between diabetes and subsequent risk of chronic LBP.DesignAn 11-year follow-up study.SettingThe Nord-Trøndelag Health Study (HUNT2; 1995–1997) and HUNT3 (2006–2008) surveys of Nord-Trøndelag County in Norway.Main outcome measureChronic LBP, defined as LBP persisting at least 3 months continuously during the last year.ParticipantsA total of 18 972 persons without chronic LBP at baseline in HUNT2, and 6802 persons who reported chronic LBP at baseline in HUNT2.MethodsAssociations between diabetes and risk of chronic LBP among individuals aged 30–69 years were examined by generalised linear modelling.ResultsMen without chronic LBP at baseline showed a significant association between diabetes and risk of chronic LBP (relative risk (RR) 1.43, 95% CI 1.04 to 1.96, p=0.043). In women, no association was found (RR 1.01, 95% CI 0.69 to 1.48, p=0.98). No association could be established between diabetes and recurrence or persistence of chronic LBP after 11 years in either sex.ConclusionsMen with a diagnosis of diabetes may have a higher risk of subsequently experiencing chronic LBP.

Cohort effects in mortality modelling: a Bayesian state-space approach

Cohort effects are important factors in determining the evolution of human mortality for certain countries. Extensions of dynamic mortality models with cohort features have been proposed in the literature to account for these factors under the generalised linear modelling framework. In this paper we approach the problem of mortality modelling with cohort factors incorporated through a novel formulation under a state-space methodology. In the process we demonstrate that cohort factors can be formulated naturally under the state-space framework, despite the fact that cohort factors are indexed according to year-of-birth rather than year. Bayesian inference for cohort models in a state-space formulation is then developed based on an efficient Markov chain Monte Carlo sampler, allowing for the quantification of parameter uncertainty in cohort models and resulting mortality forecasts that are used for life expectancy and life table constructions. The effectiveness of our approach is examined through comprehensive empirical studies involving male and female populations from various countries. Our results show that cohort patterns are present for certain countries that we studied and the inclusion of cohort factors are crucial in capturing these phenomena, thus highlighting the benefits of introducing cohort models in the state-space framework. Forecasting of cohort models is also discussed in light of the projection of cohort factors.

Linking water quality with amphibian breeding and development: a case study comparing natural ponds and Sustainable Drainage Systems (SuDS) in East Kilbride, Scotland

Amphibians have declined due to habitat loss and alteration. Sustainable Drainage Systems (SuDS) provide potential habitat for amphibians in urban landscapes. However, the contaminants they accumulate may cause increased pollutant exposure, and limited research has addressed whether differences in water quality between SuDS and natural ponds might restrict their use by amphibians. This study aimed to explore the effects of water quality on amphibian breeding and development in SuDS and natural ponds in East Kilbride, Scotland. A generalised linear modelling approach was employed to determine sources of variation in common frog (Rana temporaria) breeding and development in relation to pond size, pH, electrical conductivity (EC), chlorophyll and heavy metal concentrations. Key findings included that EC indicative of salt pollution was higher in SuDS than natural ponds, amphibians bred in both site types, but frog spawn clump densities were lower in SuDS, and tadpole development rates were higher in SuDS sites but decreased when aluminium concentrations exceeded concentrations those of surface water standards. However, pond desiccation was a significant element in the 2018 study year. It was concluded that natural ponds and SuDS varied in water quality but were important in supporting amphibian populations. However, water quality might influence amphibian development more than breeding attempts; implications and management recommendations are highlighted based on these observations.