Atopic dermatitis and bone health: a systematic review

Causal association of allergic diseases, eosinophils, and osteoporosis: A Mendelian randomization study

Background

The association between allergic diseases and osteoporosis remains controversial. We hypothesize that this discrepancy may be due to a mediator that plays a role in the pathogenesis of both allergic diseases and osteoporosis. To test this hypothesis, we used Mendelian randomization (MR) analysis to investigate the relationships among allergic diseases, eosinophils, and osteoporosis.

Method

This study utilized data from publicly available GWAS databases, including 3 allergic diseases: asthma, allergic rhinitis, and eczema. We conducted bidirectional MR analyses on the relationships between allergic diseases and eosinophils (including eosinophil counts and percentage), allergic diseases and osteoporosis, and eosinophils and osteoporosis, respectively. We conducted sensitivity analyses for results with significance, validated the findings using multivariable Mendelian randomization (MVMR) analysis to ensure the reliability of the significant results.

Results

Two-sample MR analysis revealed significant bidirectional causal relationships between the 3 allergic diseases and eosinophils. A unidirectional causal relationship was found between eosinophils and osteoporosis, with eosinophil counts associated with osteoporosis (OR: 1.194; 95% CI 1.064 to 1.339; Pivw <0.001) and eosinophil percentage associated with osteoporosis (OR: 1.187; 95% CI 1.057 to 1.332; Pivw <0.001). Sensitivity analyses indicated no pleiotropy, However, the association between eosinophil percentage and osteoporosis was no longer significant after multivariable (MVMR) analysis. Additionally, no causal effects were observed from allergic diseases to osteoporosis, from osteoporosis to allergic diseases, or from osteoporosis to eosinophils.

Conclusions

1.) There is a significant bidirectional potential causal relationship between the 3 allergic diseases (asthma, allergic rhinitis, eczema) and eosinophils. 2.) There is no evidence to support a causal relationship between the 3 allergic diseases and osteoporosis, and vice versa. 3.) There is a unidirectional causal relationship may exist from eosinophil counts to osteoporosis.

Efficacy and Safety of Dupilumab in Treating Intrinsic and Extrinsic Atopic Dermatitis in Older Patients With and Without Atopic Comorbidities: A Retrospective Study

Background: Despite the widespread use of dupilumab in atopic dermatitis (AD) treatment, evidence supporting its use in older patients with intrinsic AD (IAD) versus those with extrinsic AD (EAD) and in those with and without atopic comorbidities remains limited. Objective: We aimed to assess the clinical efficacy and safety of dupilumab treatment in elderly patients with IAD versus EAD and in those with and without atopic comorbidities. Methods: We enrolled 113 older patients with severe AD who received dupilumab for 48 weeks. The inclusion criteria were age ≥60 years and Scoring Atopic Dermatitis ≥25. Patients were classified as IAD or EAD and based on the presence of atopic comorbidities. The primary outcome was a reduction in the Eczema Area and Severity Index, Numeric Rating Scale, Dermatology Life Quality Index, and Atopic Dermatitis Control Test. Secondary measures were the types and rates of adverse events. Results: Dupilumab treatment resulted in a substantial improvement in AD symptoms, with no significant difference between patients with IAD and EAD or those with and without atopic comorbidities. Conclusions: Dupilumab showed good efficacy and safety in improving AD symptoms in older patients, irrespective of IAD or EAD subtypes and the presence of atopic comorbidities.

Longer-term safety and efficacy of baricitinib for atopic dermatitis in pediatric patients 2 to <18 years old: a randomized clinical trial of extended treatment to 3.6 years

BACKGROUND

Baricitinib, an oral selective Janus kinase inhibitor, improved clinical signs and symptoms of moderate-to-severe atopic dermatitis (AD) at week 16 in the phase 3 pediatric study BREEZE-AD-PEDS.

OBJECTIVE

To assess longer-term efficacy and safety of baricitinib in pediatric patients aged 2 to <18 years.

METHODS

In BREEZE-AD-PEDS long-term extension, responders and partial responders (validated Investigator Global Assessment-Atopic Dermatitis [vIGA-AD®] 0/1/2) at Week 16 remained on double-blind treatment to which they were randomized (placebo, baricitinib [1-mg equivalent, 2-mg equivalent, or 4-mg equivalent); non-responders (vIGA-AD 3 or 4) at Week 16 transitioned to open-label baricitinib 4-mg equivalent. Safety was summarized for all randomized patients who received ≥1 dose of study treatment.

RESULTS

In total 467 patients received baricitinib for 750.7 patient-years. Proportion of responders/partial responders (at Week 16) who achieved vIGA-AD 0/1 at Week 52 was greater for baricitinib 4-mg equivalent (56.8%) versus all other treatment groups (42.2%, 47.7%, and 39.7% for 2-mg equivalent, 1-mg equivalent, and placebo, respectively). Most treatment-emergent adverse events were mild/moderate in severity. No deaths, pulmonary emboli, deep vein thromboses or arterial thrombotic events, major adverse cardiovascular events, malignancies, tuberculosis events, or gastrointestinal perforations were reported.

CONCLUSIONS

Baricitinib demonstrated sustained long-term efficacy. No new safety signals were identified.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03952559.

The Fracture Risk of Elderly Patients With Atopic Dermatitis

Background: A higher fracture risk has been reported previously in patients with atopic Dermatitis (AD). The bone mineral density (BMD) was not accounted for in these studies. Objective: To investigate the fracture risk in AD patients after adjustment for factors including BMD. Methods: We retrospectively analyzed AD patients (≥45 years) who underwent BMD examination at our hospital from July 2010 to February 2023. Individuals who received BMD examinations during a health checkup were identified as the controls. We documented their clinical characteristics, BMD, 10-year risk for a major fracture based on FRAX (Fracture Risk Assessment Tool), and development of osteoporotic fractures. Patients were followed until development of new onset fracture or the end of the study period. A cross-sectional comparison of BMD between AD patients and controls at baseline was performed using the Mann-Whitney U test after propensity score matching (PSM). Their fracture risks were compared using the multivariate Cox regression model. BMD and fracture risk were also compared between AD patients who received systemic therapy and those who did not. Results: A total of 50 AD patients and 386 controls were enrolled. The median age was older in AD patients when compared with controls (70 years vs 60 years). Their BMD at all sites was similar after PSM. After a median follow-up of 1.7-2.0 years, 13 osteoporotic fractures were identified. In the multivariate Cox regression analysis, AD was not associated with new onset fractures of all sites (adjusted hazard ratio [aHR] 2.55, 95% confidence interval [CI] 0.72-9.01) but was significantly associated with new onset vertebral fractures (aHR 6.80, 95% CI 1.77-26.17). The BMD and incidence of fractures were similar between AD who received systemic therapy and those who did not. Conclusions: Elderly AD patients had similar BMD but a higher short-term risk for vertebral fractures when compared with the controls.

Association Between Atopic Dermatitis and Aging: Clinical Observations and Underlying Mechanisms

As one of the most prevalent chronic inflammatory skin diseases, atopic dermatitis (AD) increasingly affects the aging population. Amid the ongoing global aging trend, it's essential to recognize the intricate relationship between AD and aging. This paper reviews existing knowledge, summarizing clinical observations of associations between AD and aging-related diseases in various systems, including endocrine, cardiovascular, and neurological. Additionally, it discusses major theories explaining the correlation, encompassing skin-mucosal barriers, systemic inflammation and stress, genes, signal transduction, and environmental and behavioral factors. The association between AD and aging holds significant importance, both in population and basic perspectives. While further research is warranted, this paper aims to inspire deeper exploration of inflammation/allergy-aging dynamics and the timely management of elderly patients with AD.

Fracture risks and their mechanisms in atopic dermatitis, focusing on receptor activator of nuclear factor kappa-B ligand

Recent multiple studies have shown that the long-term consequences of atopic dermatitis (AD) include an increased risk of osteoporosis and fracture, especially an increase in hip, pelvic, spinal and wrist fractures. AD is very common worldwide, and some kinds of fractures, such as hip fractures, are associated with increased mortality, which has a substantial socioeconomic impact; however, the precise mechanisms for this remain unclear. Receptor activator of nuclear factor kappa-Β (RANK) ligand (RANKL) and osteoprotegerin (OPG) are members of the tumour necrosis factor ligand and receptor family, members of which also are known as bone biomarkers. Alterations in the RANKL/RANK/OPG system and the balance among these factors (represented by the RANKL/OPG ratio) are central to the pathogenesis of bone loss from osteoporosis, and it is postulated that there is a potential association between the serum levels of RANKL and OPG, and bone density or fracture. Recently, our research group demonstrated that the serum RANKL/OPG ratio positively correlated with AD severity and suggests fracture risk in older women with AD. This review summarizes and discusses the risk and mechanisms of osteoporotic fracture in AD. RANKL may be involved in the pathogenesis of AD, regarding not only bone abnormality but also inflammation. Although further investigation will be needed to verify the hypotheses, recent findings may provide new insights into the pathogenesis of AD and therapeutic targets.

Pooling the evidence: A review of swimming and atopic dermatitis

Swimming is an excellent form of aerobic exercise and is an essential life skill. Many children with atopic dermatitis (AD) are advised not to swim because of concerns about negative impacts on their skin disease, and some children with AD do not swim because they are self-conscious about the appearance of their skin. We aimed to perform a narrative review of the available literature on swimming and AD and scientifically analyze the potential impact of all components of swimming in AD-water, skin barrier, swimming gear, and exercise. Studies examined the impact of swimming on the skin barrier and the relative contraindications to swimming. Constituents of water which may affect AD include hardness, pH, temperature, antiseptics, and other chemicals. Potential interventions to reduce damage included emollient application, special swim gear, and showering post-submersion. The benefits of swimming as a form of exercise in AD included reduced sweating, cardiorespiratory fitness, and maintenance of healthy weight. Drawbacks of swimming as a form of exercise in AD included the limited benefit on bone mineral density. Future research should examine the impact of swimming on flares of AD using noninvasive biomarkers as well as clinical severity assessment and assess the role for different types of emollient as an intervention for optimal eczema control. This review highlights gaps in the scientific literature on swimming and AD and provides evidence-based guidance on interventions to minimize deleterious effects on skincare and maximize opportunities for children with AD to swim.

Comorbidities of atopic dermatitis-what does the evidence say?

Atopic dermatitis (AD) is a common disease that is associated with atopic and nonatopic comorbidities. There has been a growing interest in this area of AD, because presence or risk of comorbidities can in many ways impact the management of patients with AD. Thus, some treatments for AD may improve its comorbidities as well, whereas others may increase their risk. In this review article, we discuss various comorbidities of AD mostly on the basis of the results of recent multiple systematic reviews and meta-analyses to update readers about this rapidly developing area of dermatology. We emphasize the important information provided by studies presenting both relative risk and absolute risk, and show that AD is associated with, among others, atopic comorbidities such as asthma, rhinitis, and food allergy, nonatopic comorbidities such as ocular, psychiatric, infectious, endocrine, autoimmune, and cardiovascular diseases, and certain cancers. Clinicians need to be aware of these and be cognizant about positive and negative effects of existing and new treatments for AD.

Novel multimorbidity clusters in people with eczema and asthma: a population-based cluster analysis

Eczema and asthma are allergic diseases and two of the commonest chronic conditions in high-income countries. Their co-existence with other allergic conditions is common, but little research exists on wider multimorbidity with these conditions. We set out to identify and compare clusters of multimorbidity in people with eczema or asthma and people without. Using routinely-collected primary care data from the U.K. Clinical Research Practice Datalink GOLD, we identified adults ever having eczema (or asthma), and comparison groups never having eczema (or asthma). We derived clusters of multimorbidity from hierarchical cluster analysis of Jaccard distances between pairs of diagnostic categories estimated from mixed-effects logistic regressions. We analysed 434,422 individuals with eczema (58% female, median age 47 years) and 1,333,281 individuals without (55% female, 47 years), and 517,712 individuals with asthma (53% female, 44 years) and 1,601,210 individuals without (53% female, 45 years). Age at first morbidity, sex and having eczema/asthma affected the scope of multimorbidity, with women, older age and eczema/asthma being associated with larger morbidity clusters. Injuries, digestive, nervous system and mental health disorders were more commonly seen in eczema and asthma than control clusters. People with eczema and asthma of all ages and both sexes may experience greater multimorbidity than people without eczema and asthma, including conditions not previously recognised as contributing to their disease burden. This work highlights areas where there is a critical need for research addressing the burden and drivers of multimorbidity in order to inform strategies to reduce poor health outcomes.

Phytase expressed from Saccharomyces pombe ameliorates footpad lesions in cage-reared broiler chicks

BACKGROUND/AIM

The condition of footpad is an important aspect of poultry welfare. This is a problem that plagues the poultry industry because it occurs whether birds are reared in the cage or on the floor. It is reported that feeding phytase to floor-reared broiler chicks could ameliorate footpad lesions, which is related to the reduction of litter moisture. However, some studies reported that phytase supplementation could ameliorate footpad lesions, but did not affect litter quality. Therefore, phytase supplementation may have other potential mechanisms to improve the footpad lesions. Cage-reared broiler chicks were used in this study because they had no access to litter.

MATERIAL AND METHODS

A total of 234 1-day-old broiler chicks were randomly assigned to three groups based on the initial body weight (42.22 ± 0.18 g) with six replicate cages and 13 birds (mixed sex) per cage. The experimental period was 45 days. Dietary treatments were based on a corn-soybean meal-basal diet and supplemented with 500 and 750 FTU/kg Saccharomyces pombe expressed phytase. The unit of phytase (FTU) was defined as the amount of enzyme that catalyzes the release of one micromole phosphate from phytate per minute at 37°C and pH 5.5.

RESULT AND CONCLUSION

We found that dietary supplementation of S. pombe expressed phytase could improve calcium and phosphorus digestibility and subsequent improvement in toe ash, thus ameliorating footpad lesions in broiler chicks with no access to litter.

Association of clinical and social factors with risk of fracture in children with atopic dermatitis

BACKGROUND

Children with atopic dermatitis (AD) have multiple risk factors for accidental fractures, injuries that can lead to significant morbidity and mortality. However, little is known about the factors that mediate the relationship between AD and fracture in children.

OBJECTIVE

Our purpose was to examine the association of AD with fracture and to identify potential mediating factors.

METHODS

This retrospective cohort study examined children with and without AD from a longitudinal matched cohort database of 353,040 children registered in the national health insurance service and participated in the national health-screening program of Korea. We defined AD using medical claims and medication prescription records. We investigated accidental fracture events between the index date and the end of follow-up in a propensity score-matched cohort. Pre-specified subgroup analyses considered fractures in four different regions of the body. The mediating effects of 10 possible clinical factors (including the use of antihistamines and systemic corticosteroids) and social factors (including nutritional status and parental safety awareness) were determined.

RESULTS

There were 145,704 participating children, 20% with AD and 49% girls. Fractures occurred in 6,652 of the children with AD (23%, mean age: 64.6 ± 29.2 months) and in 24,698 of the control group (21%, mean age 65.0 ± 28.9 months). Children with AD had an 8% greater risk of fracture events overall (adjusted relative risk [aRR]: 1.08, 95% CI: 1.05-1.10). In subgroup analysis, AD was related to increased rates of skull and facial bone fracture (aRR: 1.09, 95% CI: 1.04-1.14), for trunk including vertebrae (aRR: 1.58, 95% CI: 1.22- 2.05), and for distal limbs (aRR: 1.11, 95% CI: 1.07-1.15). However, the relationship with proximal limb fracture was insignificant. Duration of systemic corticosteroid prescription was the largest mediating factor, followed by duration of antihistamine prescription, and infant feeding practices. In particular, the duration of systemic corticosteroid prescription was significantly associated with fracture events (incidence: 20.1% at the 25th percentile and 23.6% at the 75th percentile; difference: 3.4% [95% CI: 2.8-4.0%]).

CONCLUSIONS

Children with AD were related to increased fracture events. The key factors with mediating effects were systemic use of corticosteroid and antihistamine. Infant feeding practices had weaker mediating effects.

Atopic Eczema-Associated Fracture Risk and Oral Corticosteroids: A Population-Based Cohort Study

BACKGROUND

Evidence suggests adults with atopic eczema have increased fracture risk. However, it is unclear whether oral corticosteroids explain the association.

OBJECTIVE

To assess to what extent oral corticosteroids mediate the relationship between atopic eczema and fractures.

METHODS

We conducted a cohort study using English primary care (Clinical Practice Research Datalink) and hospital admissions (Hospital Episode Statistics) records (1998-2016) including adults (18 years old and older) with atopic eczema matched (age, sex, and general practice) with up to 5 adults without atopic eczema. We used Cox regression to estimate hazard ratios (HRs) for specific major osteoporotic fractures (hip, spine, pelvis, or wrist) and for any-site fracture comparing individuals with atopic eczema with those without, adjusting for 6 different definitions of time-updated oral corticosteroid use (ever any prescription, ever high-dose, and recent, cumulative, current, or peak dose).

RESULTS

We identified 526,808 individuals with atopic eczema and 2,569,030 without. We saw evidence of an association between atopic eczema and major osteoporotic fractures (eg, spine HR 1.15, 99% CI 1.08-1.22; hip HR 1.11, 99% CI 1.08-1.15) that remained after additionally adjusting for oral corticosteroids (eg, cumulative corticosteroid dose: spine HR 1.09, 99% CI 1.03-1.16; hip HR 1.09, 99% CI 1.06-1.12). Fracture rates were higher in people with severe atopic eczema than in people without even after adjusting for oral corticosteroids (eg, spine HR [99% CI]: confounder-adjusted 2.31 [1.91-2.81]; additionally adjusted for cumulative dose 1.71 [1.40-2.09]).

CONCLUSIONS

Our findings suggest that little of the association between atopic eczema and major osteoporotic fractures is explained by oral corticosteroid use.

Fracture risks in patients with atopic dermatitis: A nationwide matched cohort study

BACKGROUND

The risk of osteoporosis has been explored in atopic dermatitis (AD). The long-term risk of fractures in patients with AD and the effects of various AD treatments on bone health remain to be elucidated.

OBJECTIVE

To evaluate the long-term risk of fractures in patients with AD.

METHODS

This nationwide matched cohort study was conducted using the National Health Insurance Research Database of Taiwan for the period 1997 to 2013. A total of 36,855 patients with AD and 147,420 reference subjects without AD were identified. Demographic characteristics and comorbidities were compared, and cumulative incidence of fractures was evaluated. Adjusted hazard ratios for fracture risks of AD and various AD treatments were calculated using the Cox proportional hazards model.

RESULTS

A total of 1518 patients (4.12%) in the AD cohort and 5579 patients (3.78%) in the reference cohort had fractures (P = .003). The mean ages were 22.6 years in both groups. The 16-year cumulative incidence of fractures in the AD cohort (8.043%) was significantly higher than that in the reference cohort (7.366%) (P = .002). Severe AD (adjusted hazard ratio [aHR], 1.31; 95% confidence interval [CI], 1.08-1.59) was independently associated with fractures. Other independent risk factors included exposure to topical (aHR, 1.21; 95% CI, 1.05-1.39) or systemic (≥10 mg/d; aHR, 1.62; 95% CI, 1.38-1.91) corticosteroids. Use of disease-modifying antirheumatic drugs (aHR, 0.71; 95% CI, 0.53-0.90) and phototherapy (aHR, 0.73; 95% CI, 0.56-0.95) was associated with a lower risk of fractures. The results were consistent across sensitivity analyses.

CONCLUSION

Patients with AD have a higher incidence of fractures. Severe AD is independently associated with fractures.