Validation of algorithms in studies based on routinely collected health data: general principles.

Clinicians, researchers, regulators, and other decision-makers increasingly rely on evidence from real-world data (RWD), including data routinely accumulating in health and administrative databases. RWD studies often rely on algorithms to operationalize variable definitions. An algorithm is a combination of codes or concepts used to identify persons with a specific health condition or characteristic. Establishing the validity of algorithms is a prerequisite for generating valid study findings that can ultimately inform evidence-based health care. This paper aims to systematize terminology, methods, and practical considerations relevant to the conduct of validation studies of RWD-based algorithms. We discuss measures of algorithm accuracy; gold/reference standard; study size; prioritizing accuracy measures; algorithm portability; and implication for interpretation. Information bias is common in epidemiologic studies, underscoring the importance of transparency in decisions regarding choice and prioritizing measures of algorithm validity. The validity of an algorithm should be judged in the context of a data source, and one size does not fit all. Prioritizing validity measures within a given data source depends on the role of a given variable in the analysis (eligibility criterion, exposure, outcome or covariate). Validation work should be part of routine maintenance of RWD sources.

Urticaria and the risk of cancer: a Danish population-based cohort study.

BACKGROUND: Urticaria has been tentatively linked to cancer, but epidemiological evidence supporting this link is sparse and conflicting. We conducted a population-based cohort study using healthcare databases covering the Danish population (January 1980-December 2022). We followed 87 507 people for a median of 10.1 years after their first hospital contact for urticaria. OBJECTIVES: To examine associations of a hospital diagnosis of urticaria with incident cancer. METHODS: We computed the absolute risk of cancer and standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) standardized to Danish national cancer rates. In a cross-sectional analysis, we examined whether the extent of cancer spread differed between people with vs. without a previous urticaria diagnosis. RESULTS: The overall SIR for all types of cancer was 1.09 (95% CI 1.06-1.11) based on 7788 observed vs. 7161 expected cases. The risk for any cancer was 0.7% (95% CI 0.6-0.7) for the first year of follow-up. Cancer was diagnosed in 588 people with urticaria during the first year of follow-up (SIR 1.49, 95% CI 1.38-1.62) and in 7200 people thereafter (SIR 1.06, 95% CI 1.04-1.09). During the first year of follow-up, we found strong associations with haematological cancers (e.g. non-Hodgkin lymphoma; SIR 2.91, 95% CI 1.92-4.23). Cancer stage was similar in people with vs. without a previous urticaria diagnosis. CONCLUSIONS: At the time of urticaria diagnosis, or in the first year afterward, we found a large increase in the risk of cancer. In subsequent years, a persistent 6% increase in risk remained. Diagnostic efforts may partly explain the elevated short-term risk, but occult cancer may promote urticaria, or cancer and urticaria share common risk factors.

Urticaria (also known as hives) is a common skin condition that causes wheals and/or angioedema (swelling). Approximately 9% of people will experience it in their lifetime. Urticaria is classified according to how long the symptoms last and is considered to be 'chronic' when the wheals and/or angioedema last for 6 weeks or more. Case studies have suggested that urticaria may be linked to cancers where the primary origin is not known. Only two other studies have compared different groups of people to estimate the risk and association between urticaria and cancer. Using healtcare information from Danish databases, we looked at the risk of cancer in people with urticaria and compared it with the general population. To do this, we followed 87,507 people for around 10 years after they first attended hospital for urticaria. We found that the risk of getting any cancer was 0.7% for the first year of follow-up. Cancer was diagnosed in 588 people with urticaria during the first year of follow-up and in 7,200 people after the first year. In the first year of follow-up, we found there was a strong association with blood cancers like non-Hodgkin lymphoma. Cancer stage was similar in people with a diagnosis of urticaria versus those without it. Our findings suggest that urticaria could be associated with a higher short-term risk of cancer, but the overall risk is low. Cancer of an unknown origin could promote urticaria, or cancer and urticaria share common risk factors.

An expert consensus on managing dupilumab-related ocular surface disorders in people with atopic dermatitis 2024.

BACKGROUND: Atopic dermatitis (AD) is the most common inflammatory skin condition which affects all ages. New therapies, including the monoclonal antibody therapy dupilumab, offer excellent efficacy. However, in clinical trials, and emphasised in real-world observations, the unexpected increased frequency of ocular adverse effects became apparent. The effectiveness of dupilumab and the unpredictability of ocular adverse effects mean that clinicians need guidance on counselling patients prior to treatment and on managing them if they arise. OBJECTIVES: The British Association of Dermatologists (BAD) and Royal College of Ophthalmologists collaborated on this consensus guidance on managing dupilumab-related ocular surface disorders (DROSD). METHODS: A multidisciplinary group was formed of adult and paediatric dermatologists and ophthalmologists with DROSD expertise, patient representation, and BAD Clinical Standards Unit. A literature search was conducted, and the results reviewed. All recommendations were reviewed, discussed and voted on. RESULTS: The recommendations pertain to dermatology and ophthalmology management, and apply to all ages, unless otherwise stated. Importantly, initiation of dupilumab for AD should not be delayed for most eye disorders except acute new problems, e.g. infections, or potentially severe conditions, e.g. a history of corneal transplant (ophthalmology advice should be sought first). There is insufficient evidence to recommend lubricant drops prophylactically. Dermatologists should assess eye complaints to diagnose DROSD; a severity grading system is provided. DROSD management differs slightly in those aged <7 years as ocular complications may affect neuro-ocular development; therefore, irrespective of DROSD severity, this population should be referred for ophthalmology advice. In those aged ≥7 years, dermatologists should feel confident to trial treatment and reserve ophthalmology advice for severe or non-responding cases. Discussion about dupilumab withdrawal should be prompted by a significant impact on quality of life, threat to sight, or other complications. CONCLUSIONS: Although dupilumab is a highly effective agent for treating AD, the risk of ocular adverse effects should not inhibit clinicians or patients from using it, but clinicians should be aware of them. If a patient develops DROSD, there are clear pathways to assess severity and offer initial management; where ineffective, dermatologists should assess the urgency and seek advice from or initiate referral to ophthalmology. While the evidence reviewed for these guidelines reflects the extensive literature on dupilumab, we believe our advice has relevance for ocular surface disorders in atopic dermatitis (AD) patients treated with tralokinumab and lebrikizumab.

Defining disease severity in atopic dermatitis and psoriasis for the application to biomarker research: an interdisciplinary perspective.

More severe atopic dermatitis and psoriasis are associated with a higher cumulative impact on quality of life, multimorbidity and healthcare costs. Proactive, early intervention in those most at risk of severe disease may reduce this cumulative burden and modify the disease trajectory to limit progression. The lack of reliable biomarkers for this at-risk group represents a barrier to such a paradigm shift in practice. To expedite discovery and validation, the BIOMarkers in Atopic Dermatitis and Psoriasis (BIOMAP) consortium (a large-scale European, interdisciplinary research initiative) has curated clinical and molecular data across diverse study designs and sources including cross-sectional and cohort studies (small-scale studies through to large multicentre registries), clinical trials, electronic health records and large-scale population-based biobanks. We map all dataset disease severity instruments and measures to three key domains (symptoms, inflammatory activity and disease course), and describe important codependencies and relationships across variables and domains. We prioritize definitions for more severe disease with reference to international consensus, reference standards and/or expert opinion. Key factors to consider when analysing datasets across these diverse study types include explicit early consideration of biomarker purpose and clinical context, candidate biomarkers associated with disease severity at a particular point in time and over time and how they are related, taking the stage of biomarker development into account when selecting disease severity measures for analyses, and validating biomarker associations with disease severity outcomes using both physician- and patient-reported measures and across domains. The outputs from this exercise will ensure coherence and focus across the BIOMAP consortium so that mechanistic insights and biomarkers are clinically relevant, patient-centric and more generalizable to current and future research efforts.

Atopic dermatitis (AD), and psoriasis are long-term skin conditions that can significantly affect people's lives, especially when symptoms are severe. Approximately 10% of adults and 20% of children are affected by AD, while psoriasis affects around 5% of people in the UK. Both conditions are associated with debilitating physical symptoms (such as itch) and have been linked to depression and anxiety. Biomarkers are naturally occurring chemicals in the human body and have potential to enhance the longer-term management of AD and psoriasis. Currently, there are no routinely used biomarkers that can identify people who experience or will go on to develop severe AD and psoriasis. For this reason, research is under way to understand which biomarkers are linked to severity. In this study, a multidisciplinary team of skin researchers from across Europe, along with patient groups, discussed the complexities of studying severity-related biomarkers. We identified a number of severity measurement approaches and there were recommendations for future biomarker research, including (i) considering multiple measures as no single measure can encompass all aspects of severity, (ii) exploring severity measures recorded by both healthcare professionals and patients, as each may capture different aspects, and (iii) accounting for influencing factors, such as different treatment approaches, that may impact AD and psoriasis severity, which make it challenging to compare findings across studies. Overall, we anticipate that the insights gained from these discussions will increase the likelihood of biomarkers being effectively applied in real-world settings, to ultimately improve outcomes for people with AD and psoriasis.

Core Concepts in Pharmacoepidemiology: Quantitative Bias Analysis.

Pharmacoepidemiological studies provide important information on the safety and effectiveness of medications, but the validity of study findings can be threatened by residual bias. Ideally, biases would be minimized through appropriate study design and statistical analysis methods. However, residual biases can remain, for example, due to unmeasured confounders, measurement error, or selection into the study. A group of sensitivity analysis methods, termed quantitative bias analyses, are available to assess, quantitatively and transparently, the robustness of study results to these residual biases. These approaches include methods to quantify how the estimated effect would be altered under specified assumptions about the potential bias, and methods to calculate bounds on effect estimates. This article introduces quantitative bias analyses for unmeasured confounding, misclassification, and selection bias, with a focus on their relevance and application to pharmacoepidemiological studies.

Disagreement concerning atopic dermatitis subtypes between an English prospective cohort (ALSPAC) and linked electronic health records.

BACKGROUND: Subtypes of atopic dermatitis (AD) have been derived from the Avon Longitudinal Study of Parents and Children (ALSPAC) based on presence and severity of symptoms reported in questionnaires (Severe-Frequent, Moderate-Frequent, Moderate-Declining, Mild-Intermittent, Unaffected/Rare). Good agreement between ALSPAC and linked electronic health records (EHRs) would increase trust in the clinical validity of these subtypes and allow inferring subtypes from EHRs alone, which would enable their study in large primary care databases. OBJECTIVES: 1. Explore if presence and number of AD records in EHRs agrees with AD symptom and severity reports from ALSPAC; 2. Explore if EHRs agree with ALSPAC-derived AD subtypes; 3. Construct models to classify ALSPAC-derived AD subtype using EHRs. METHODS: We used data from the ALSPAC prospective cohort study from 11 timepoints until age 14 years (1991-2008), linked to local general practice EHRs. We assessed how far ALSPAC questionnaire responses and derived subtypes agreed with AD as established in EHRs using different AD definitions (e.g., diagnosis and/or prescription) and other AD-related records. We classified AD subtypes using EHRs, fitting multinomial logistic regression models tuning hyperparameters and evaluating performance in the testing set (ROC AUC, accuracy, sensitivity, and specificity). RESULTS: 8,828 individuals out of a total 13,898 had both been assigned an AD subtype and had linked EHRs. The number of AD-related codes in EHRs generally increased with severity of AD subtype, however not all with the Severe-Frequent subtypes had AD in EHRs, and many with the Unaffected/Rare subtype did have AD in EHRs. When predicting ALSPAC AD subtype using EHRs, the best tuned model had ROC AUC of 0.65, sensitivity of 0.29 and specificity of 0.83 (both macro averaged); when different sets of predictors were used, individuals with missing EHR coverage excluded, and subtypes combined, sensitivity was not considerably improved. CONCLUSIONS: ALSPAC and EHRs disagreed not just on AD subtypes, but also on whether children had AD or not. Researchers should be aware that individuals considered as having AD in one source may not be considered as having AD in another.

Educational, labour market and relationship outcomes in people with acne.

BACKGROUND: Although acne is associated with scarring, mental health comorbidities and bullying, little is known about its impact on socio-economic outcomes. OBJECTIVES: To examine the association between acne and educational, labour market and relationship outcomes. METHODS: We conducted a nationwide registry-based cohort study in Denmark. We included birth cohorts from 1982 to 1988 and compared those with and without acne identified using hospital diagnosis codes and redeemed prescriptions. Our main educational outcome was educational attainment. The main labour market outcomes were earned income at age 30 and long-term unemployment at any time before age 30. The main relationship outcomes were single partnership and childlessness by age 30. Outcomes were assessed using Poisson regression for binary outcomes and linear regression for continuous outcomes, adjusted for sex, calendar year, mother's socio-economic position and hormonal contraception use. RESULTS: Those with acne had a lower risk of not completing upper secondary education (relative risk (RR): 0.79; 95% confidence interval [CI]: 0.76-0.83) and higher education (RR: 0.90; 95% CI: 0.88-0.91), with absolute differences up to 4 percentage points. Persons with acne had slightly higher income (mean percentile difference: 2.6%, 95% CI: 2.2-2.9) and lower risk of long-term unemployment than those without acne (9.8% vs. 11.4%; RR: 0.90; 95% CI: 0.87-0.93). The prevalence of being single until age 30 was similar (19.7% vs. 20.1%; adjusted RR: 0.96; 95% CI: 0.94-0.98) but childlessness was slightly more prevalent (60.5% vs. 57.5%; adjusted RR: 1.03; 95% CI: 1.02-1.04). However, all associations were attenuated or lost in secondary analysis restricted to exposure-discordant siblings to address confounding from family-related factors. CONCLUSIONS: Acne during adolescence does not seem to affect long-term educational, labour market or relationship outcomes. However, there is a need for additional studies to validate the findings in untreated patients and different health and social systems.

Common mental health disorders in adults with inflammatory skin conditions: nationwide population-based matched cohort studies in the UK.

BACKGROUND: Psoriasis and atopic eczema are common inflammatory skin diseases. Existing research has identified increased risks of common mental disorders (anxiety, depression) in people with eczema and psoriasis; however, explanations for the associations remain unclear. We aimed to establish the risk factors for mental illness in those with eczema or psoriasis and identify the population groups most at risk. METHODS: We used routinely collected data from the UK Clinical Practice Research Datalink (CPRD) GOLD. Adults registered with a general practice in CPRD (1997-2019) were eligible for inclusion. Individuals with eczema/psoriasis were matched (age, sex, practice) to up to five adults without eczema/psoriasis. We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for hazards of anxiety or depression in people with eczema/psoriasis compared to people without. We adjusted for known confounders (deprivation, asthma [eczema], psoriatic arthritis [psoriasis], Charlson comorbidity index, calendar period) and potential mediators (harmful alcohol use, body mass index [BMI], smoking status, and, in eczema only, sleep quality [insomnia diagnoses, specific sleep problem medications] and high-dose oral glucocorticoids). RESULTS: We identified two cohorts with and without eczema (1,032,782, matched to 4,990,125 without), and with and without psoriasis (366,884, matched to 1,834,330 without). Sleep quality was imbalanced in the eczema cohorts, twice as many people with eczema had evidence of poor sleep at baseline than those without eczema, including over 20% of those with severe eczema. After adjusting for potential confounders and mediators, eczema and psoriasis were associated with anxiety (adjusted HR [95% CI]: eczema 1.14 [1.13-1.16], psoriasis 1.17 [1.15-1.19]) and depression (adjusted HR [95% CI]: eczema 1.11 [1.1-1.12], psoriasis 1.21 [1.19-1.22]). However, we found evidence that these increased hazards are unlikely to be constant over time and were especially high 1-year after study entry. CONCLUSIONS: Atopic eczema and psoriasis are associated with increased incidence of anxiety and depression in adults. These associations may be mediated through known modifiable risk factors, especially sleep quality in people with eczema. Our findings highlight potential opportunities for the prevention of anxiety and depression in people with eczema/psoriasis through treatment of modifiable risk factors and enhanced eczema/psoriasis management.

Atopic dermatitis across the life course.

Atopic dermatitis, the most common chronic inflammatory skin disease, can occur at any age, and patterns of disease activity vary over time. Both prevalence and incidence are highest in infancy and early childhood, followed by a second peak in older adulthood. Birth cohort studies from European countries following children through adolescence have identified subgroups of patients with early-onset persistent disease, early-onset resolving disease, and later-onset disease. Parental history of atopy and genetic factors are among the most consistent predictors of more persistent disease. Studies have begun to examine whether molecular markers differ by age group, although longitudinal data are lacking. Breastfeeding, probiotics and skin-directed therapies such as emollients have been investigated as potential preventive measures, but randomized trials have not found consistent long-term benefit. Future research should focus on patterns of disease activity beyond early adulthood and the role of treatments on long-term disease activity.

In utero or early in life exposure to antibiotics and the risk of childhood atopic dermatitis, a population-based cohort study.

BACKGROUND: Atopic dermatitis (AD) is a common inflammatory disease of the skin that begins early in life and can be lifelong. The purpose of our study was to evaluate whether fetal exposure and/or early life exposure of a child to antibiotics increases the risk of early onset AD. OBJECTIVE: We hypothesize that antibiotic exposure in utero or early in life (e.g., first 90 days) increases the likelihood that children develop AD. METHODS: Utilizing a large prospectively collected electronic medical records database, we studied the association of antibiotic exposure received in utero or very early in life and the relative risk of onset of AD in a population-based cohort study. Associations were estimated using proportional hazards models as hazard ratios (HR) with 95% confidence intervals (CI). RESULTS: The risk of AD in childhood was increased after in utero or early life antibiotic exposure. For any in utero AB exposure the HR was 1.38 (1.36,1.39). However, penicillin demonstrated the strongest association with AD for both in utero exposure, 1.43 (1.41,1.44), and for childhood exposure, 1.81(1.79,1.82). HRs were higher in children born to mothers without AD than those with AD pointing to effect modification by maternal AD status. CONCLUSION: Children born to mothers exposed to antibiotics while in utero had, depending on the mother's history of AD, approximately a 20 to 40% increased risk of developing AD. Depending on the antibiotic, children who received antibiotics early-in-life had a 40 to 80% increased risk of developing AD. Our study, supports and refines the association between incident AD and antibiotic administration. It also adds population-based support to therapeutic attempts to treat AD by modifying skin microbiome.

Long-term oral antibiotic use in people with acne vulgaris in UK primary care: a drug utilization study.

BACKGROUND: The inappropriate use of antibiotics is understood to contribute to antimicrobial resistance. Oral antibiotics are regularly used to treat moderate-to-severe acne vulgaris. In practice, we do not know the typical length of oral antibiotic treatment courses for acne in routine primary care and what proportion of people receive more than one course of treatment following a new acne diagnosis. OBJECTIVES: To describe how oral antibiotics are prescribed for acne over time in UK primary care. METHODS: We conducted a descriptive longitudinal drug utilization study using routinely collected primary care data from the Clinical Practice Research Datalink GOLD (2004-2019). We included individuals (8-50 years) with a new acne diagnosis recorded between 1 January 2004 and 31 July 2019. RESULTS: We identified 217 410 people with a new acne diagnosis. The median age was 17 years [interquartile range (IQR) 15-25] and median follow-up was 4.3 years (IQR 1.9-7.6). Among people with a new acne diagnosis, 96 703 (44.5%) received 248 560 prescriptions for long-term oral antibiotics during a median follow-up of 5.3 years (IQR 2.8-8.5). The median number of continuous courses of antibiotic therapy (≥ 28 days) per person was four (IQR 2-6). The majority (n = 59 010, 61.0%) of first oral antibiotic prescriptions in those with a recorded acne diagnosis were between the ages of 12 and 18. Most (n = 71 544, 74.0%) first courses for oral antibiotics were for between 28 and 90 days. The median duration of the first course of treatment was 56 days (IQR 50-93 days) and 18 127 (18.7%) of prescriptions of ≥ 28 days were for < 6 weeks. Among people who received a first course of oral antibiotic for ≥ 28 days, 56 261 (58.2%) received a second course after a treatment gap of ≥ 28 days. The median time between first and second courses was 135 days (IQR 67-302). The cumulative duration of exposure to oral antibiotics during follow-up was 255 days (8.5 months). CONCLUSIONS: Further work is needed to understand the consequences of using antibiotics for shorter periods than recommended. Suboptimal treatment duration may result in reduced clinical effectiveness or repeated exposures, potentially contributing to antimicrobial resistance.

Factors associated with depression, anxiety and severe mental illness among adults with atopic eczema or psoriasis: a systematic review and meta-analysis.

BACKGROUND: Evidence suggests an association between atopic eczema (AE) or psoriasis and mental illness; however, the factors associated with mental illness are unclear. OBJECTIVES: To synthesize and evaluate all available evidence on factors associated with depression, anxiety and severe mental illness (SMI) among adults with AE or psoriasis. METHODS: We searched electronic databases, grey literature databases and clinical trial registries from inception to February 2022 for studies of adults with AE or psoriasis. Eligible studies included randomized controlled trials (RCTs), cohort, cross-sectional or case-control studies where effect estimates of factors associated with depression, anxiety or SMI were reported. We did not apply language or geographical restrictions. We assessed risk of bias using the Quality in Prognosis Studies tool. We synthesized results narratively, and if at least two studies were sufficiently homogeneous, we pooled effect estimates in a random effects meta-analysis. RESULTS: We included 21 studies (11 observational, 10 RCTs). No observational studies in AE fulfilled our eligibility criteria. Observational studies in people with psoriasis mostly investigated factors associated with depression or anxiety - one cross-sectional study investigated factors associated with schizophrenia. Pooled effect estimates suggest that female sex and psoriatic arthritis were associated with depression [female sex: odds ratio (OR) 1.62, 95% confidence interval (CI) 1.09-2.40, 95% prediction intervals (PIs) 0.62-4.23, I2 = 24.90%, τ2 = 0.05; psoriatic arthritis: OR 2.26, 95% CI 1.56-3.25, 95% PI 0.21-24.23, I2 = 0.00%, τ2 = 0.00] and anxiety (female sex: OR 2.59, 95% CI 1.32-5.07, 95% PI 0.00-3956.27, I2 = 61.90%, τ2 = 0.22; psoriatic arthritis: OR 1.98, 95% CI 1.33-2.94, I2 = 0.00%, τ2 = 0.00). Moderate/severe psoriasis was associated with anxiety (OR 1.14, 95% CI 1.05-1.25, I2 0.00%, τ2 = 0.00), but not depression. Evidence from RCTs suggested that adults with AE or psoriasis given placebo had higher depression and anxiety scores compared with comparators given targeted treatment (e.g. biologic agents). CONCLUSIONS: Our review highlights limited existing research on factors associated with depression, anxiety and SMI in adults with AE or psoriasis. Observational evidence on factors associated with depression or anxiety in people with psoriasis was conflicting or from single studies, but some identified factors were consistent with those in the general population. Evidence on factors associated with SMIs in people with AE or psoriasis was particularly limited. Evidence from RCTs suggested that AE and psoriasis treated with placebo was associated with higher depression and anxiety scores compared with skin disease treated with targeted therapy; however, follow-up was limited. Therefore, long-term effects on mental health are unclear.

'Eczema shouldn't control you; you should control eczema': qualitative process evaluation of online behavioural interventions to support young people and parents/carers of children with eczema.

BACKGROUND: There is a lack of well-conducted randomized controlled trials evaluating the effectiveness of theory-based online interventions for eczema. To address these deficiencies, we previously developed and demonstrated the effectiveness of two online behavioural interventions: Eczema Care Online for parents/carers of children with eczema, and Eczema Care Online for young people with eczema. OBJECTIVES: To explore the views and experiences of people who have used the Eczema Care Online interventions to provide insights into how the interventions worked and identify contextual factors that may impede users' engagement with the interventions. METHODS: Qualitative semistructured interviews were conducted with 17 parents/carers of children with eczema and 17 young people with eczema. Participants were purposively sampled from two randomized controlled trials of the interventions and recruited from GP surgeries in England. Transcripts were analysed using inductive thematic analysis, and intervention modifications were identified using the person-based approach table of changes method. RESULTS: Both young people and parents/carers found the interventions easy to use, relatable and trustworthy, and perceived that they helped them to manage their eczema, thus suggesting that Eczema Care Online may be acceptable to its target groups. Our analysis suggested that the interventions may reduce eczema severity by facilitating empowerment among its users, specifically through improved understanding of, and confidence in, eczema management, reduced treatment concerns, and improved treatment adherence and management of irritants/triggers. Reading about the experiences of others with eczema helped people to feel 'normal' and less alone. Some (mainly young people) expressed firmly held negative beliefs about topical corticosteroids, views that were not influenced by the intervention. Minor improvements to the design and navigation of the Eczema Care Online interventions and content changes were identified and made, ready for wider implementation. CONCLUSIONS: People with eczema and their families can benefit from reliable information, specifically information on the best and safest ways to use their eczema treatments early in their eczema journey. Together, our findings from this study and the corresponding trials suggest wider implementation of Eczema Care Online (EczemaCareOnline.org.uk) is justified.

Nonadherence to systemic immune-modifying therapy in people with psoriasis during the COVID-19 pandemic: findings from a global cross-sectional survey.

BACKGROUND: Nonadherence to immune-modifying therapy is a complex behaviour which, before the COVID-19 pandemic, was shown to be associated with mental health disorders in people with immune-mediated diseases. The COVID-19 pandemic has led to a rise in the global prevalence of anxiety and depression, and limited data exist on the association between mental health and nonadherence to immune-modifying therapy during the pandemic. OBJECTIVES: To assess the extent of and reasons underlying nonadherence to systemic immune-modifying therapy during the COVID-19 pandemic in individuals with psoriasis, and the association between mental health and nonadherence. METHODS: Online self-report surveys (PsoProtectMe), including validated screens for anxiety and depression, were completed globally during the first year of the pandemic. We assessed the association between anxiety or depression and nonadherence to systemic immune-modifying therapy using binomial logistic regression, adjusting for potential cofounders (age, sex, ethnicity, comorbidity) and country of residence. RESULTS: Of 3980 participants from 77 countries, 1611 (40.5%) were prescribed a systemic immune-modifying therapy. Of these, 408 (25.3%) reported nonadherence during the pandemic, most commonly due to concerns about their immunity. In the unadjusted model, a positive anxiety screen was associated with nonadherence to systemic immune-modifying therapy [odds ratio (OR) 1.37, 95% confidence interval (CI) 1.07-1.76]. Specifically, anxiety was associated with nonadherence to targeted therapy (OR 1.41, 95% CI 1.01-1.96) but not standard systemic therapy (OR 1.16, 95% CI 0.81-1.67). In the adjusted model, although the directions of the effects remained, anxiety was not significantly associated with nonadherence to overall systemic (OR 1.20, 95% CI 0.92-1.56) or targeted (OR 1.33, 95% CI 0.94-1.89) immune-modifying therapy. A positive depression screen was not strongly associated with nonadherence to systemic immune-modifying therapy in the unadjusted (OR 1.22, 95% CI 0.94-1.57) or adjusted models (OR 1.14, 95% CI 0.87-1.49). CONCLUSIONS: These data indicate substantial nonadherence to immune-modifying therapy in people with psoriasis during the pandemic, with attenuation of the association with mental health after adjusting for confounders. Future research in larger populations should further explore pandemic-specific drivers of treatment nonadherence. Clear communication of the reassuring findings from population-based research regarding immune-modifying therapy-associated adverse COVID-19 risks to people with psoriasis is essential, to optimize adherence and disease outcomes.

Relationship between Eczema and Self-reported Difficulties Keeping up with School Education: A Cross-sectional Study.

Eczema is a common chronic disease that affects both children and adults, and may have an adverse impact on school performance, as it is characteristically pruritic, and hence may lead to poor concentration and inadequate sleep. The aim of this study was to elucidate the relationship between eczema and self-reported difficulties keeping up with school education. The study was based on cross-sectional questionnaire data collected in schools among all 9th graders (15-16 years old) within a Swedish county. Logistic regression analyses were used to assess the association between having eczema and self-reported difficulties keeping up with school education. A total of 2,620 pupils participated (50.1% female). An increased odds ratio (OR) of self-reported difficulties keeping up with school education was found in adolescents with eczema compared with those without eczema after adjustment for sex and  family residence (OR 2.13, 95% confidence interval (95% CI) 1.32-3.44), and with additional adjustment for sleeping problems, attention-deficit hyperactivity disorder, allergy, rhinitis, asthma, and alcohol consumption (adjusted OR 1.78, CI 1.05-3.00). Eczema may be a relevant risk factor for difficulty keeping up with school education in adolescents. However, studies that can assess temporality, based in different settings with objective reports of both eczema and self-reported difficulties at school, are needed to confirm these findings.

The association between atopic eczema and lymphopenia: Results from a UK cohort study with replication in US survey data.

BACKGROUND: Lymphocyte skin homing in atopic eczema (AE) may induce lymphopenia. OBJECTIVE: To determine if AE is associated with lymphopenia. METHODS: We used UK primary care electronic health records (Clinical Practice Research Datalink GOLD) for a matched cohort study in adults (18 years+) (1997-2015) with at least one recorded lymphocyte count. We matched people with AE to up to five people without. We used multivariable logistic regression to estimate the association between AE and lymphopenia (two low lymphocyte counts within 3 months) and linear mixed effects regression to estimate the association with absolute lymphocyte counts using all available counts. Cox proportional hazard models were used to investigate the effect of lymphopenia on common infections. We replicated the study using US survey data (National Health and Nutrition Examination Survey [NHANES]). RESULTS: Among 71,731 adults with AE and 126,349 adults without AE, we found an adjusted odds ratio (OR) for lymphopenia of 1.16 (95% CI: 1.09-1.23); the strength of association increased with increasing eczema severity. When comparing all recorded lymphocyte counts from adults with AE (n = 1,497,306) to those of people without AE (n = 4,035,870) we saw a lower mean lymphocyte (adjusted mean difference -0.047 × 109 /L [95% CI: -0.051 to -0.043]) in those with AE. The difference was larger for men, with increasing age, and with increasing AE severity and was present among people with AE not treated with immunosuppressive drugs. In NHANES (n = 22,624), the adjusted OR for lymphopenia in adults with AE was 1.30 (95% CI: 0.80-2.11), and the adjusted mean lymphocyte count difference was -0.03 × 109 /L (95% CI: -0.07 to 0.02). Despite having a lower lymphocyte count, adjusting for time with lymphopenia, did not alter risk estimates of infections. CONCLUSION: Atopic eczema, including increasing AE severity, is associated with a decreased lymphocyte count, regardless of immunosuppressive drug use. Whether the lower lymphocyte count has wider health implications for people with severe eczema warrants further investigation.

Mixed evidence on the relationship between socioeconomic position and atopic dermatitis: A systematic review.

BACKGROUND: Lower socioeconomic position usually portends worse health outcomes, but multiple studies have found that atopic dermatitis is associated with higher socioeconomic position. The nature of this relationship remains unclear. OBJECTIVE: To systematically review the literature on socioeconomic position and atopic dermatitis and determine whether the association varies by patient or study characteristics. METHODS: A literature search was conducted in the PubMed and Embase databases. Individual-level studies addressing the association between all measures of socioeconomic position and the prevalence or incidence of atopic dermatitis were eligible for inclusion. Two independent reviewers screened all texts and extracted all data for qualitative synthesis. RESULTS: Eighty-eight studies met the inclusion criteria. Of the 88 studies, 42% (37) found a positive association between atopic dermatitis and socioeconomic position, 15% (13) found a negative association, and 43% (38) found a null or inconsistent association. Studies conducted in Europe, among children, and based on self-report of eczema were more likely to find a positive association with socioeconomic position. LIMITATIONS: Studies varied both in terms of the measurement of socioeconomic position and the definition of atopic dermatitis, limiting quantitative synthesis. CONCLUSION: The evidence of a positive association between atopic dermatitis and socioeconomic position is not consistent.

Adult atopic eczema and the risk of dementia: A population-based cohort study.

BACKGROUND: Chronic inflammatory conditions have been linked to dementia, but little is known about the role of atopic eczema, an inflammatory condition recently recognized to be common among older adults. OBJECTIVE: To determine whether active atopic eczema is associated with incident dementia. METHODS: A longitudinal cohort study of 1,767,667 individuals aged 60 to 99 years registered with The Health Improvement Network, a primary care cohort in the United Kingdom. The diagnoses of atopic eczema and dementia were identified using medical record codes. RESULTS: The incidence of dementia was 57 per 10,000 person-years among those with atopic eczema during follow-up (12.1% of the population) compared with 44 per 10,000 person-years in the control group. This translated to a 27% increased risk of dementia (hazard ratio, 1.27; 95% CI, 1.23-1.30) in adjusted Cox proportional hazard models. Similar associations were observed in subgroup analyses of vascular dementia and Alzheimer's disease. The association persisted after additionally adjusting for the use of systemic corticosteroids (hazard ratio, 1.29; 95% CI, 1.26-1.33) and potential mediators (hazard ratio, 1.19; 95% CI, 1.16-1.22). More severe eczema was associated with a higher risk of dementia. LIMITATIONS: Lack of detailed data on severity. CONCLUSION: Atopic eczema was associated with a small but increased risk of incident dementia. The association increased with the severity of atopic eczema.

Atopic eczema in adulthood and mortality: UK population-based cohort study, 1998-2016.

BACKGROUND: Atopic eczema affects up to 10% of adults and is becoming more common globally. Few studies have assessed whether atopic eczema increases the risk of death. OBJECTIVE: We aimed to determine whether adults with atopic eczema were at increased risk of death overall and by specific causes and to assess whether the risk varied by atopic eczema severity and activity. METHODS: The study was a population-based matched cohort study using UK primary care electronic health care records from the Clinical Practice Research Datalink with linked hospitalization data from Hospital Episode Statistics and mortality data from the Office for National Statistics from 1998 to 2016. RESULTS: A total of 526,736 patients with atopic eczema were matched to 2,567,872 individuals without atopic eczema. The median age at entry was 41.8 years, and the median follow-up time was 4.5 years. There was limited evidence of increased hazard for all-cause mortality in those with atopic eczema (hazard ratio = 1.04; 99% CI = 1.03-1.06), but there were somewhat stronger associations (8%-14% increased hazard) for deaths due to infectious, digestive, and genitourinary causes. Differences on the absolute scale were modest owing to low overall mortality rates. Mortality risk increased markedly with eczema severity and activity. For example, patients with severe atopic eczema had a 62% increased hazard (hazard ratio = 1.62; 99% CI = 1.54-1.71) for mortality compared with those without eczema, with the strongest associations for infectious, respiratory, and genitourinary causes. CONCLUSION: The increased hazards for all-cause and cause-specific mortality were largely restricted to those with the most severe or predominantly active atopic eczema. Understanding the reasons for these increased hazards for mortality is an urgent priority.

Factors associated with adverse COVID-19 outcomes in patients with psoriasis-insights from a global registry-based study.

BACKGROUND: The multimorbid burden and use of systemic immunosuppressants in people with psoriasis may confer greater risk of adverse outcomes of coronavirus disease 2019 (COVID-19), but the data are limited. OBJECTIVE: Our aim was to characterize the course of COVID-19 in patients with psoriasis and identify factors associated with hospitalization. METHODS: Clinicians reported patients with psoriasis with confirmed/suspected COVID-19 via an international registry, Psoriasis Patient Registry for Outcomes, Therapy and Epidemiology of COVID-19 Infection. Multiple logistic regression was used to assess the association between clinical and/or demographic characteristics and hospitalization. A separate patient-facing registry characterized risk-mitigating behaviors. RESULTS: Of 374 clinician-reported patients from 25 countries, 71% were receiving a biologic, 18% were receiving a nonbiologic, and 10% were not receiving any systemic treatment for psoriasis. In all, 348 patients (93%) were fully recovered from COVID-19, 77 (21%) were hospitalized, and 9 (2%) died. Increased hospitalization risk was associated with older age (multivariable-adjusted odds ratio [OR] = 1.59 per 10 years; 95% CI = 1.19-2.13), male sex (OR = 2.51; 95% CI = 1.23-5.12), nonwhite ethnicity (OR = 3.15; 95% CI = 1.24-8.03), and comorbid chronic lung disease (OR = 3.87; 95% CI = 1.52-9.83). Hospitalization was more frequent in patients using nonbiologic systemic therapy than in those using biologics (OR = 2.84; 95% CI = 1.31-6.18). No significant differences were found between classes of biologics. Independent patient-reported data (n = 1626 across 48 countries) suggested lower levels of social isolation in individuals receiving nonbiologic systemic therapy than in those receiving biologics (OR = 0.68; 95% CI = 0.50-0.94). CONCLUSION: In this international case series of patients with moderate-to-severe psoriasis, biologic use was associated with lower risk of COVID-19-related hospitalization than with use of nonbiologic systemic therapies; however, further investigation is warranted on account of potential selection bias and unmeasured confounding. Established risk factors (being older, being male, being of nonwhite ethnicity, and having comorbidities) were associated with higher hospitalization rates.