Increased risk of herpes zoster in children with asthma: a population-based case-control study

Risk factors for herpes zoster infections: a systematic review and meta-analysis unveiling common trends and heterogeneity patterns

PURPOSE

The burden of herpes zoster (HZ) is substantial and numerous chronic underlying conditions are known as predisposing risk factors for HZ onset. Thus, a comprehensive study is needed to synthesize existing evidence. This study aims to comprehensively identify these risk factors.

METHODS

A systematic literature search was done using MEDLINE via PubMed, EMBASE and Web of Science for studies published from January 1, 2003 to January 1, 2023. A random-effects model was used to estimate pooled Odds Ratios (OR). Heterogeneity was assessed using the I2 statistic. For sensitivity analyses basic outlier removal, leave-one-out validation and Graphic Display of Heterogeneity (GOSH) plots with different algorithms were employed to further analyze heterogeneity patterns. Finally, a multiple meta-regression was conducted.

RESULTS

Of 6392 considered records, 80 were included in the meta-analysis. 21 different conditions were identified as potential risk factors for HZ: asthma, autoimmune disorders, cancer, cardiovascular disorders, chronic heart failure (CHF), chronic obstructive pulmonary disorder (COPD), depression, diabetes, digestive disorders, endocrine and metabolic disorders, hematological disorders, HIV, inflammatory bowel disease (IBD), mental health conditions, musculoskeletal disorders, neurological disorders, psoriasis, renal disorders, rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and transplantation. Transplantation was associated with the highest risk of HZ (OR = 4.51 (95% CI [1.9-10.7])). Other risk factors ranged from OR = 1.17-2.87, indicating an increased risk for all underlying conditions. Heterogeneity was substantial in all provided analyses. Sensitivity analyses showed comparable results regarding the pooled effects and heterogeneity.

CONCLUSIONS

This study showed an increased risk of HZ infections for all identified factors.

Serious neurological adverse events in immunocompetent children and adolescents caused by viral reactivation in the years following varicella vaccination

Serious adverse events following vaccination include medical complications that require hospitalisation. The live varicella vaccine that was approved by the Food and Drug Administration in the United States in 1995 has an excellent safety record. Since the vaccine is a live virus, adverse events are more common in immunocompromised children who are vaccinated inadvertently. This review includes only serious adverse events in children considered to be immunocompetent. The serious adverse event called varicella vaccine meningitis was first reported in a hospitalised immunocompetent child in 2008. When we carried out a literature search, we found 15 cases of immunocompetent children and adolescents with varicella vaccine meningitis; the median age was 11 years. Eight of the children had received two varicella vaccinations. Most of the children also had a concomitant herpes zoster rash, although three did not. The children lived in the United States, Greece, Germany, Switzerland, and Japan. During our literature search, we found five additional cases of serious neurological events in immunocompetent children; these included 4 cases of progressive herpes zoster and one case of acute retinitis. Pulses of enteral corticosteroids as well as a lack of herpes simplex virus antibody may be risk factors for reactivation in immunocompetent children. All 20 children with adverse events were treated with acyclovir and recovered; 19 were hospitalised and one child was managed as an outpatient. Even though the number of neurological adverse events remains exceedingly low following varicella vaccination, we recommend documentation of those caused by the vaccine virus.

Association of asthma and herpes zoster, the role of vaccination: A literature review

Herpes Zoster (HZ) is the reactivation of a previous infection with varicella-zoster virus (VZV) which shares the same mode of transmission as HZ. It presents with painful erythematous vesicles in a dermatome which is characterized by a burning sensation before and after the rash. Any conditions with suppressed cellular immunity example diabetes mellitus, chronic obstructive pulmonary disease, asthma, cardiovascular diseases, chronic steroid uses, malignancy, etc. causes reactivation of the virus. Impaired immune responses in asthma patients either in any age group may increase their susceptibility to HZ infection owing to skewed Th1/Th2 immunity, resulting in predominant Th2 conditions and an unwarranted Th2 cell response against respiratory allergens. Similarly, many studies have delineated the association of asthma with HZ. However, the relation between steroid use in asthma and HZ is uncertain, its immunosuppressive effect might be responsible for increased susceptibility to the infection. As HZ increases the economic burden and morbidity, its prevention should use vaccines. There are two types of Food and Drug Administration (FDA)-approved vaccine available against HSV one of which is given as a single dose vaccine called Zostavax, for people 50-59 years but its efficacy falls after 3rd dose and on the subsequent 4th dose and is also contraindicated in human immunodeficiency virus/acquired immunodeficiency syndrome, pregnancy and people taking immunosuppressive drugs. Shingrix is preferred by FDA which is a two doses vaccine that is given 6 months apart for people above 50 years and to immunocompromised people. Hence, proper counseling and education about the risks of herpes should be informed to the patients with timely utilization of the vaccine.

Clinical features in childhood herpes zoster and predisposing factors: a retrospective study

Aim: Herpes Zoster is a disease characterized by vesicles with dermatomal distribution, resulting from the reactivation of the Varicella Zoster Virus. It is more common in older ages and in children with immunosuppression. This study was designed to evaluate the clinical features and predisposing factors of children diagnosed with Herpes Zoster. Materials and Methods: Data of the patients under 16 years of age that were diagnosed with Herpes zoster at our dermatology outpatient clinic were retrospectively evaluated between January 2015 and March 2021. Patients' age, gender, complaints, duration of complaints, varicella vaccines, chickenpox history, additional systemic diseases, accompanying viral infections and other predisposing factors were determined. In addition, dermatomal extent of the rash, treatments and complications were reviewed. Results: Out of 67 cases enrolled in the study; 44 (65.7%) were male and 23 (34.3%) were female. The mean age of the patients was 9.7 ± 2.9 years. The most common complaint was itching in the lesion area (44.8%). The most frequently involved dermatome was thoracic dermatome (56.7%). Immunosuppression or malignancy was not detected in any patient. Conjunctivitis developed in two cases and secondary bacterial infection in three cases. The most common predisposing factor was stress (38.8%). Conclusion: Herpes zoster is not a cutaneous indicator of an underlying immunosuppression or malignancy in children and has a good clinical course. The disease is mostly accompanied by predisposing factors such as stress, viral infections and sun exposure.

Atopic asthma as a potentially significant but unrecognized risk factor for Kawasaki disease in children

OBJECTIVES

Childhood asthma is known to be associated with risks of both respiratory and non-respiratory infections. Little is known about the relationship between asthma and the risk of Kawasaki disease (KD). We assessed associations of asthma status and asthma phenotype (e.g. atopic asthma) with KD.

METHODS

We performed a population-based retrospective case-control study, using KD cases between January 1, 1979, and December 31, 2016, and two matched controls per case. KD cases were defined by the American Heart Association diagnostic criteria. Asthma status prior to KD (or control) index dates was ascertained by the two asthma criteria, Predetermined Asthma Criteria (PAC) and Asthma Predictive Index (API, a surrogate phenotype of atopic asthma). We assessed whether 4 phenotypes (both PAC + and API+; PAC + only; API + only, and non-asthmatics) were associated with KD.

RESULTS

There were 124 KD cases during the study period. The group having both PAC + and API + was significantly associated with the increased odds of KD, compared to non-asthmatics (odds ratio [OR] 4.3; 95% CI: 1.3 - 14.3). While asthma defined by PAC was not associated with KD, asthma defined by PAC positive with eosinophilia (≥4%) was significantly associated with the increased odds of KD (OR: 6.7; 95% CI: 1.6 - 28.6) compared to non-asthmatics. Asthma status defined by API was associated with KD (OR = 4.7; 95% CI: 1.4-15.1).

CONCLUSIONS

Atopic asthma may be associated with increased odds of KD. Further prospective studies are needed to determine biological mechanisms underlying the association between atopic asthma and increased odds of KD.

Evaluation of Atopic Dermatitis and Cutaneous Infectious Disorders Using Sequential Pattern Mining: A Nationwide Population-Based Cohort Study

According to previous studies, the increased risk of cutaneous infectious disorders in patients with atopic dermatitis (AD) is related to impaired epidermal function, abnormal systemic immune function, and lower antimicrobial peptides. In this study, we analyzed the association between AD and cutaneous infectious disorders in the real world using sequential pattern mining (SPM). We analyzed National Health Insurance data from 2010–2013 using SPM to identify comorbid cutaneous infectious diseases and the onset durations of comorbidities. Patients with AD were at greater risk for molluscum contagiosum (adjusted odds ratio (aOR), 5.273), impetigo (aOR, 2.852), chickenpox (aOR, 2.251), otitis media (aOR, 1.748), eczema herpeticum (aOR, 1.292), and viral warts (aOR, 1.105). In SPM analysis, comorbidity of 1.06% shown in molluscum contagiosum was the highest value, and the duration of 77.42 days documented for molluscum contagiosum was the shortest onset duration among all the association rules. This study suggests that AD is associated with an increased risk of cutaneous infectious disorders. In particular, care should be taken regarding its high relevance with impetigo, molluscum contagiosum, and otitis media, which may help in preventing AD from worsening through appropriately preventing and managing the condition.

Establishing an expert consensus for the operational definitions of asthma-associated infectious and inflammatory multimorbidities for computational algorithms through a modified Delphi technique

BACKGROUND

A subgroup of patients with asthma has been reported to have an increased risk for asthma-associated infectious and inflammatory multimorbidities (AIMs). To systematically investigate the association of asthma with AIMs using a large patient cohort, it is desired to leverage a broad range of electronic health record (EHR) data sources to automatically identify AIMs accurately and efficiently.

METHODS

We established an expert consensus for an operational definition for each AIM from EHR through a modified Delphi technique. A series of questions about the operational definition of 19 AIMS (11 infectious diseases and 8 inflammatory diseases) was generated by a core team of experts who considered feasibility, balance between sensitivity and specificity, and generalizability. Eight internal and 5 external expert panelists were invited to individually complete a series of online questionnaires and provide judgement and feedback throughout three sequential internal rounds and two external rounds. Panelists' responses were collected, descriptive statistics tabulated, and results reported back to the entire group. Following each round the core team of experts made iterative edits to the operational definitions until a moderate (≥ 60%) or strong (≥ 80%) level of consensus among the panel was achieved.

RESULTS

Response rates for each Delphi round were 100% in all 5 rounds with the achievement of the following consensus levels: (1) Internal panel consensus: 100% for 8 definitions, 88% for 10 definitions, and 75% for 1 definition, (2) External panel consensus: 100% for 12 definitions and 80% for 7 definitions.

CONCLUSIONS

The final operational definitions of AIMs established through a modified Delphi technique can serve as a foundation for developing computational algorithms to automatically identify AIMs from EHRs to enable large scale research studies on patient's multimorbidities associated with asthma.

Corticosteroid Use and Risk of Herpes Zoster in a Population-Based Cohort

OBJECTIVE

To examine the relationship between corticosteroid use and herpes zoster risk.

METHODS

With data from a large cohort of adults (the 45 and Up Study) recruited between 2006 and 2009 and linked to health data sets, the effect of corticosteroid use on zoster risk was analyzed by Cox proportional hazards models, adjusting for age, sex, and other characteristics.

RESULTS

During 602,152 person-years (median, 7.36 years) of follow-up, there were 20,048 new systemic corticosteroid users and 6294 incident herpes zoster events among 94,677 participants (zoster incidence, 11.0 per 1000 person-years). Compared with nonusers, the risk of zoster was 59% higher in those using systemic corticosteroids (adjusted hazard ratio [aHR], 1.59; 95% CI, 1.48 to 1.71) and greater with higher cumulative doses: aHR of 1.32 (95% CI, 1.17 to 1.48), 1.74 (95% CI, 1.55 to 1.95), and 1.80 (95% CI, 1.61 to 2.02) for use of less than 500 mg, 500 mg to less than 1000 mg, and 1000 mg or more prednisolone equivalents, respectively (P value for trend, <.001). Compared with nonusers, zoster risk increased significantly (aHR, 6.00; 95% CI, 4.85 to 7.42) in the month after a single prescription of systemic corticosteroids and returned to levels similar to those in nonusers by the third month after dispensing (aHR, 0.91; 95% CI, 0.49 to 1.69).

CONCLUSION

Practitioners should be alert to the increased risk of zoster among patients taking systemic corticosteroids. Given the significant morbidity from zoster, particularly in older adults, these findings support judicious prescribing of corticosteroids, including using as low a dose and as short a course as possible.

Risk, Mechanisms and Implications of Asthma-Associated Infectious and Inflammatory Multimorbidities (AIMs) among Individuals With Asthma: a Systematic Review and a Case Study

Our prior work and the work of others have demonstrated that asthma increases the risk of a broad range of both respiratory (e.g., pneumonia and pertussis) and non-respiratory (e.g., zoster and appendicitis) infectious diseases as well as inflammatory diseases (e.g., celiac disease and myocardial infarction [MI]), suggesting the systemic disease nature of asthma and its impact beyond the airways. We call these conditions asthma-associated infectious and inflammatory multimorbidities (AIMs). At present, little is known about why some people with asthma are at high-risk of AIMs, and others are not, to the extent to which controlling asthma reduces the risk of AIMs and which specific therapies mitigate the risk of AIMs. These questions represent a significant knowledge gap in asthma research and unmet needs in asthma care, because there are no guidelines addressing the identification and management of AIMs. This is a systematic review on the association of asthma with the risk of AIMs and a case study to highlight that 1) AIMs are relatively under-recognized conditions, but pose major health threats to people with asthma; 2) AIMs provide insights into immunological and clinical features of asthma as a systemic inflammatory disease beyond a solely chronic airway disease; and 3) it is time to recognize AIMs as a distinctive asthma phenotype in order to advance asthma research and improve asthma care. An improved understanding of AIMs and their underlying mechanisms will bring valuable and new perspectives improving the practice, research, and public health related to asthma.

Herpes Simplex Virus Pneumonia in an Immunocompetent Child on Corticosteroids for Acute Wheezing

Herpes simplex virus (HSV) is rarely the cause of pneumonia in immunocompetent patients. We describe a previously healthy child, with no evidence of an immunodeficiency, who presented to the emergency department with severe pneumonia, wheezing, and pleural effusions with a history of orolabial HSV infection. On admission, he was started on antibiotics and systemic corticosteroids but continued to deteriorate. Oral lesions, blood, and pleural fluid tested positive for HSV, and improvement was achieved only after the addition of acyclovir and discontinuation of steroids. We suggest that steroids should be used with caution in patients presenting with lower respiratory tract symptoms and herpetic oral lesions.

Varicella Vaccine Meningitis as a Complication of Herpes Zoster in Twice-Immunized Immunocompetent Adolescents

Varicella-zoster virus vaccination is recommended for virtually all young children in the United States, Canada, and several other countries. Varicella vaccine is a live attenuated virus that retains some of its neurotropic properties. Herpes zoster caused by vaccine virus still occurs in immunized children, although the rate is much lower than in children who had wild-type varicella. It was commonly thought that 2 varicella vaccinations would protect children against the most serious complication of meningitis following herpes zoster; however, 2 meningitis cases have already been published. We now report a third case of varicella vaccine meningitis and define risk factors shared by all 3 immunized adolescents. The diagnosis in cerebrospinal fluid in this third case was verified by amplifying and sequencing portions of the viral genome, to document fixed alleles found only in the vaccine strain. Viral antibody was also detected in the cerebrospinal fluid by confocal microscopy. When compared with the other 2 cases, remarkably all 3 were 14 years old when meningitis occurred. All 3 were treated with intravenous acyclovir, with complete recovery. The adolescent in our case report also had recurrent asthma, which was treated with both prednisone tablets and beclomethasone inhaler before onset of meningitis. When the 3 cases were considered together, they suggested that immunity to varicella-zoster virus may be waning sufficiently in some twice-immunized adolescents to make them vulnerable to varicella vaccine virus reactivation and subsequent meningitis. This complication rarely happens in children after wild-type varicella.

Asthma increases the risk of herpes zoster: a nested case-control study using a national sample cohort

Background

This study aimed to complement previous studies on the risk of herpes zoster in the asthmatic adult population.

Methods

The Korean Health Insurance Review and Assessment Service—National Sample Cohort (HIRA-NSC) from 2002 through 2013 was used. A total of 64,152 participants with herpes zoster were matched for age, sex, income, region of residence, hypertension, diabetes, and dyslipidemia with 239,780 participants who were included as a control group. In both the herpes zoster and control groups, previous history of asthma were investigated. The crude and adjusted odds ratios (ORs) and 95% confidence intervals (CI) of asthma for herpes zoster were analyzed using unconditional logistic regression analysis. Subgroup analyses were conducted according to age and sex.

Results

Approximately 16.2% (9728/59,945) and 12.8% (30,752/239,780) of participants in the herpes zoster and control groups, respectively, had a previous history of asthma (P < 0.001). The herpes zoster group demonstrated a 1.32-times higher odds of asthma than the control group (95% CI 1.28–1.35, P < 0.001). The increased odds of asthma in the herpes zoster group persisted in all the age and sex subgroups.

Conclusions

The odds for asthma were higher in the herpes zoster group.

Allergic Immune Diseases and the Risk of Mortality Among Patients Hospitalized for Acute Infection

OBJECTIVES

The immune response during sepsis remains poorly understood and is likely influenced by the host's preexisting immunologic comorbidities. Although more than 20% of the U.S. population has an allergic-atopic disease, the type 2 immune response that is overactive in these diseases can also mediate beneficial pro-resolving, tissue-repair functions. Thus, the presence of allergic immunologic comorbidities may be advantageous for patients suffering from sepsis. The objective of this study was to test the hypothesis that comorbid type 2 immune diseases confer protection against morbidity and mortality due to acute infection.

DESIGN

Retrospective cohort study of patients hospitalized with an acute infection between November 2008 and January 2016 using electronic health record data.

SETTING

Single tertiary-care academic medical center.

PATIENTS

Admissions to the hospital through the emergency department with likely infection at the time of admission who may or may not have had a type 2 immune-mediated disease, defined as asthma, allergic rhinitis, atopic dermatitis, or food allergy, as determined by International Classification of Diseases, 9th Revision, Clinical Modification codes.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 10,789 admissions for infection, 2,578 (24%) had a type 2 disease; these patients were more likely to be female, black, and younger than patients without type 2 diseases. In unadjusted analyses, type 2 patients had decreased odds of dying during the hospitalization (0.47; 95% CI, 0.38-0.59, p < 0.001), while having more than one type 2 disease conferred a dose-dependent reduction in the risk of mortality (p < 0.001). When adjusting for demographics, medications, types of infection, and illness severity, the presence of a type 2 disease remained protective (odds ratio, 0.55; 95% CI, 0.43-0.70; p < 0.001). Similar results were found using a propensity score analysis (odds ratio, 0.57; 95% CI, 0.45-0.71; p < 0.001).

CONCLUSIONS

Patients with type 2 diseases admitted with acute infections have reduced mortality, implying that the type 2 immune response is protective in sepsis.

A diagnostic codes-based algorithm improves accuracy for identification of childhood asthma in archival data sets

OBJECTIVE

While a single but truncated ICD code (493) had been widely used for identifying asthma in asthma care and research, it significantly under-identifies asthma. We aimed to develop and validate a diagnostic codes-based algorithm for identifying asthmatics using Predetermined Asthma Criteria (PAC) as the reference.

METHODS

This is a retrospective cross-sectional study which utilized two different coding systems, the Hospital Adaptation of the International Classification of Diseases, Eighth Revision (H-ICDA) and the International Classification of Diseases, Ninth Revision (ICD-9). The algorithm was developed using two population-based asthma study cohorts, and validated in a validation cohort, a random sample of the 1976-2007 Olmsted County Birth Cohort. Performance of the diagnostic codes-based algorithm for ascertaining asthma status against manual chart review for PAC (gold standard) was assessed by determining both criterion and construct validity.

RESULTS

Among eligible 267 subjects of the validation cohort, 50% were male, 70% white, and the median age at last follow-up was 17 (interquartile range, 8.7-24.4) years. Asthma prevalence by PAC through manual chart review was 34%. Sensitivity and specificity of the codes-based algorithm for identifying asthma were 82% and 98% respectively. Associations of asthma-related risk factors with asthma status ascertained by the code-based algorithm were similar to those by the manual review.

CONCLUSIONS

The diagnostic codes-based algorithm for identifying asthmatics improves accuracy of identification of asthma and can be a useful tool for large scale studies in a setting without automated chart review capabilities.

Safety of Eosinophil-Depleting Therapy for Severe, Eosinophilic Asthma: Focus on Benralizumab

Eosinophils play a pivotal role in the inflammatory pathology of asthma and have been the target of new biologic treatments for patients with eosinophilic asthma. Given the central role of interleukin (IL)-5 in the eosinophil lifecycle, several therapies directed against the IL-5 pathway have been developed, including the anti-IL-5 antibodies mepolizumab and reslizumab and the IL-5 receptor α (IL-5Rα)-directed cytolytic antibody benralizumab. Eosinophil-depleting therapies represent a relatively new class of asthma treatment, and it is important to understand their long-term efficacy and safety. Eosinophils have been associated with host protection and tumor growth, raising potential concerns about the consequences of long-term therapies that deplete eosinophils. However, evidence for these associations in humans is conflicting and largely indirect or based on mouse models. Substantial prospective clinical trial and postmarketing data have accrued, providing insight into the potential risks associated with eosinophil depletion. In this review, we explore the current safety profile of eosinophil-reducing therapies, with particular attention to the potential risks of malignancies and severe infections and a focus on benralizumab. Benralizumab is an IL-5Rα-directed cytolytic monoclonal antibody that targets and efficiently depletes blood and tissue eosinophils through antibody-dependent cell-mediated cytotoxicity. Benralizumab is intended to treat patients with severe, uncontrolled asthma with eosinophilic inflammation. The integrated analyses of benralizumab safety data from the phase III SIROCCO and CALIMA trials and subsequent BORA extension trial for patients with asthma, and the phase III GALATHEA and TERRANOVA trials for patients with chronic obstructive pulmonary disease, form the principal basis for this review.

Quantitative proteomics analysis of the treatment of asthma rats with total flavonoid extract from chamomile

OBJECTIVE

Asthma is a chronic immune disease that has become a serious public health problem. The currently available medications are not ideal because of their limitations and side effects; hence, new target proteins and signaling cascades for precise and safe therapy treatment are needed. This work established an ovalbumin-induced asthma rat model and treated it with total flavonoid extract from the Xinjiang chamomile. The proteins that were differentially expressed in the chamomile extract-treated asthmatic rats and the asthma and healthy rat groups were identified using isobaric tagging followed by LC-MS/MS. Kyoto encyclopedia of genes and genomes pathway analysis of the differentially expressed proteins was performed.

RESULTS

Pathways involved in purine metabolism, herpes simplex infection, and JNK phosphorylation and activation mediated by activated human TAK1 were enriched, indicating the intrinsic links between the mechanism of asthma development and treatment effects. Furthermore, we constructed a protein-protein interaction network and identified KIF3A as a potential target protein of chamomile extract that affected the Hedgehog signaling pathway.

CONCLUSIONS

This study may provide new insights into the pathogenesis of asthma and reveal several proteins and pathways that could be exploited to develop novel treatment approaches.

Increased risk of appendectomy in patients with asthma: A nested case-control study using a national sample cohort

The study aimed to expand previous data regarding an association between asthma and appendectomy in children compared with the population of all ages.The Korean Health Insurance Review and Assessment Service-National Sample Cohort from 2002 through 2013 was used. In all, 22,030 participants who underwent appendectomy were matched for age, sex, income, region of residence, hypertension, diabetes, and dyslipidemia with 88,120 participants who were included as a control group. In both the appendectomy and control groups, previous history of asthma was investigated. Appendectomy for appendicitis was identified based on a surgical code (International Classification of Disease-10 [ICD-10]: K35). Asthma was classified using an ICD-10 code (J45 and J46) and medication history. The crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of asthma for appendectomy were analyzed using conditional logistic regression analysis. Subgroup analyses were conducted according to age and sex.Approximately 15.2% (3358/22,030) of individuals in the appendectomy group and 13.3% (11,749/88,120) of those in the control group had asthma (P < .001). The appendectomy group demonstrated a higher adjusted odds of asthma than the control group (adjusted OR 1.18, 95% CI 1.13-1.23, P < .001). This result was consistent in the subgroups divided according to age and sex.The odds for asthma were higher in the appendectomy group than in the control group.

A clinico-epidemiological multicenter study of herpes zoster in immunocompetent and immunocompromised hospitalized children

Purpose

There are limited population-based data regarding herpes zoster in children. Thus we conducted a multi-institutional epidemiological analysis of herpes zoster in children and comparative analysis according to their immune status.

Materials and Methods

The study included 126 children under the age of 18 years who were hospitalized for herpes zoster at 8 hospitals in South Korea, between July 2009 and June 2015. The subjects were divided into 2 groups according to their immune status, and medical records were reviewed.

Results

There were 61 cases (48.4%) in the immunocompetent group and 65 cases (51.6%) in the immunocompromised group. Median age was older in immunocompromised group (11.4 vs. 8.6) (p<0.001). The mean duration of hospitalization was longer in immunocompromised group (11.0 vs. 6.6) (p<0.001). Patients were treated with oral or intravenous antiviral agents. A total of 12 in immunocompetent group were cured only by oral acyclovir. No treatment failure was found in both groups. Six immunocompromised patients had postherpetic neuralgia and 1 case was in immunocompetent group. In immunocompetent children, herpes zoster was likely caused by early varicella infection. There was no increase in progression of severity in both groups due to appropriate treatment.

Conclusion

Early initiation of therapy is necessary for those in immunocompromised conditions. And inactivated herpes zoster vaccination may be considered in immunocompromised adolescents in the future.

Herpes Zoster Eruption in an Otherwise Healthy Child: A Case Report

Varicella-zoster virus (VZV; human herpesvirus 3) is a herpesvirus that causes infection in humans. The reactivation of latent VZV manifests as herpes zoster or shingles. In immunocompetent children, reactivation is rare, as increasing age is the most common risk factor for reactivation. The complications of infection include post-herpetic neuralgia and neurological sequelae as well as a bacterial infection of the crusted skin. We present a case of an otherwise healthy 13-year-old child with herpes zoster and multiple risk factors, who was managed successfully, in order to expand the limited literature. The patient presented with a painful vesicular rash, which appeared as multiple grouped vesicles on an erythematous base spreading over the right half of the face. The diagnosis of herpetic (varicella) vesiculobullous dermatitis was confirmed by biopsy and the patient was started on acyclovir and clindamycin with gradual improvement and resolution of his symptoms. Reactivation of VZV is considered a consequence of decreased cell-mediated immunity. However, the reason for reactivation in immunocompetent children remains unclear. In the present case, the patient may have become exposed in utero, through vaccination, or as a result of major facial trauma sustained at the age of six years.

Asthma and risk of glioma: a population-based case-control study

OBJECTIVES

Literature suggests an inconsistent, but largely inverse, association between asthma and risk of glioma, which is primarily due to methodological inconsistency in sampling frame and ascertainment of asthma. The objective of the study was to clarify the association between asthma and risk of glioma by minimising methodological biases (eg, recall and detection bias).

DESIGN

A population-based case-control study.

SETTING

General population in Olmsted County, Minnesota, USA.

PARTICIPANTS

All eligible biopsy-proven incident glioma cases (1995-2014) and two sets of controls among residents matched to age and sex (first set: community controls without glioma; second set: MRI-negative controls from the same community).

METHODS

The predetermined asthma criteria via medical record review were applied to ascertain asthma status of cases and controls. History of asthma prior to index date was compared between glioma cases and their matched controls using conditional logistic regression models. Propensity score for asthma status was adjusted for multivariate analysis.

RESULTS

We enrolled 135 glioma cases (median age at index date: 53 years) and 270 controls. Of the cases, 21 had a history of asthma (16%), compared with 36 of MRI controls (27%) (OR (95% CI) 0.48 (0.26 to 0.91), p=0.03). With MRI controls, an inverse association between asthma and risk of glioma persisted after adjusting for the propensity score for asthma status, but did not reach statistical significance probably due to the lack of statistical power (OR (95% CI) 0.48 (0.21 to 1.09); p=0.08). Based on comparison of characteristics of controls and cases, community controls seem to be more susceptible to a detection bias.

CONCLUSIONS

While differential detection might account for the association between asthma and risk of glioma, asthma may potentially pose a protective effect on risk of glioma. Our study results need to be replicated by a larger study.

Severe Herpes Zoster Following Varicella Vaccination in Immunocompetent Young Children

Varicella vaccination is now virtually universal in North America, as well as in some European and Asian countries. Since varicella vaccine is a live attenuated virus, the virus replicates in the skin after administration and can travel via sensory nerves or viremia to become latent in the dorsal root ganglia. In some immunized children, virus reactivates within a few months to a few years to cause the dermatomal exanthem known as herpes zoster (shingles). Herpes zoster caused by vaccine virus often reactivates within the same dermatome as the site of the original varicella vaccine injection. We present evidence that occasional cases of herpes zoster following varicella vaccination in immunocompetent children can be as severe as herpes zoster following wild-type varicella. Analysis of the virus in one case disclosed that the vaccine virus causing herpes zoster was a wild-type variant with a mutation in ORF0. With regard to dermatomal localization of the viral eruption, we predict that herpes zoster of the lumbar dermatomes in children is likely to be caused by vaccine virus, because herpes zoster in those dermatomes is rare in children after wild-type varicella. One of the children with herpes zoster subsequently developed asthma, a known risk factor for herpes zoster, but none of the children had an autoimmune disease. Although postherpetic neuralgia is exceedingly rare, children who develop herpes zoster following varicella vaccination are at risk (albeit low) of developing meningoencephalitis and should be carefully observed for a few weeks.

Early Identification of Childhood Asthma: The Role of Informatics in an Era of Electronic Health Records

Emerging literature suggests that delayed identification of childhood asthma results in an increased risk of long-term and various morbidities compared to those with timely diagnosis and intervention, and yet this risk is still overlooked. Even when children and adolescents have a history of recurrent asthma-like symptoms and risk factors embedded in their medical records, this information is sometimes overlooked by clinicians at the point of care. Given the rapid adoption of electronic health record (EHR) systems, early identification of childhood asthma can be achieved utilizing (1) asthma ascertainment criteria leveraging relevant clinical information embedded in EHR and (2) innovative informatics approaches such as natural language processing (NLP) algorithms for asthma ascertainment criteria to enable such a strategy. In this review, we discuss literature relevant to this topic and introduce recently published informatics algorithms (criteria-based NLP) as a potential solution to address the current challenge of early identification of childhood asthma.

Heterogeneity of asthma and the risk of celiac disease in children

BACKGROUND

Although human leukocyte antigen (HLA)-DR and HLA-DQ genes and gluten play crucial roles in developing celiac disease (CD), most patients with these risk factors still do not develop CD, which indicates additional unrecognized risk factors.

OBJECTIVE

To determine the association between asthma and the risk of CD in children.

METHODS

We conducted a population-based retrospective case-control study in children who resided in Olmsted County, Minnesota. We identified children with CD (cases) between January 1, 1997, and December 31, 2014, and compared these with children without CD (controls) (1:2 matching). Asthma status was ascertained by using the predetermined asthma criteria (PAC) and the asthma predictive index (API). Data analysis included conditional logistic regression models and an unsupervised network analysis by using an independent phenome-wide association scan (PheWAS) data set.

RESULTS

Although asthma status as determined by using PAC was not associated with the risk of CD (odds ratio [OR] 1.4 [95% confidence interval {CI}, 0.8-2.5]; p = 0.2), asthma status by using the API was significantly associated (OR 2.8 [95% CI, 1.3-6.0]; p = 0.008). A subgroup analysis indicated that children with both asthma as determined by using PAC and a family history of asthma had an increased risk of CD compared with those without asthma (OR 2.28 [95% CI, 1.11-4.67]; p = 0.024). PheWAS data showed a cluster of asthma single nucleotide polymorphisms and patients with CD.

CONCLUSION

A subgroup of children with asthma who also had a family history of asthma seemed to be at an increased risk of CD, and, thus, the third factor that underlies the risk of CD might be related to genetic factors for asthma. Heterogeneity of asthma plays a role in determining the risk of asthma-related comorbidity.

Asthma status is an independent risk factor for herpes zoster in children: a population-based cohort study

BACKGROUNDS

Literatures regarding the effects of childhood asthma on the risk of herpes zoster (HZ) is very limited. The aim of this study is to investigate the risks of children developing HZ with asthma.

METHODS

From the National Health Insurance Research Database, we identified 300,649 patients who had asthma between 2000 and 2007 as an asthma cohort. We identified another matched non-asthma cohort. All subjects were followed until the end of 2008. A Cox model was used to estimate the association of asthma on the risk of HZ.

RESULTS

Asthma cohort had significantly higher risk of developing HZ than the comparison cohort (HR=1.15; 95 % CI =1.06-1.26). However, compared to those without regular controller, asthma cohort with regular inhaled corticosteroid (ICS) treatment had slightly increased risk for HZ (HR=1.14; 95% CI=1.01-1.27) but decreased risk for HZ in those with regular combined ICS and Montelukast (HR=0.83; 95% CI=0.69-0.98). Uncontrolled asthma with more than 3-4 times ED visits and admissions per year had 3.72 (CI =1.86-7.47) and 20.5 (CI =10.2-41.2) greater risks for HZ than those without asthma, respectively.

CONCLUSIONS

Asthma poses an increased risk of zoster, therefore control of asthma is important to minimize risk of HZ.

Asthma and the Risk of Rheumatoid Arthritis: An Insight into the Heterogeneity and Phenotypes of Asthma

Asthma is traditionally regarded as a chronic airway disease, and recent literature proves its heterogeneity, based on distinctive clusters or phenotypes of asthma. In defining such asthma clusters, the nature of comorbidity among patients with asthma is poorly understood, by assuming no causal relationship between asthma and other comorbid conditions, including both communicable and noncommunicable diseases. However, emerging evidence suggests that the status of asthma significantly affects the increased susceptibility of the patient to both communicable and noncommunicable diseases. Specifically, the impact of asthma on susceptibility to noncommunicable diseases such as chronic systemic inflammatory diseases (e.g., rheumatoid arthritis), may provide an important insight into asthma as a disease with systemic inflammatory features, a conceptual understanding between asthma and asthma-related comorbidity, and the potential implications on the therapeutic and preventive interventions for patients with asthma. This review discusses the currently under-recognized clinical and immunological phenotypes of asthma; specifically, a higher risk of developing a systemic inflammatory disease such as rheumatoid arthritis and their implications, on the conceptual understanding and management of asthma. Our discussion is divided into three parts: literature summary on the relationship between asthma and the risk of rheumatoid arthritis; potential mechanisms underlying the association; and implications on asthma management and research.

Asthma and Risk of Appendicitis in Children: A Population-Based Case-Control Study

OBJECTIVE

To assess whether asthma is associated with risk of appendicitis in children.

METHODS

We used a population-based case-control study design using a comprehensive medical record review and predetermined criteria for appendicitis and asthma. All children (age younger than 18 years of age) who resided in Olmsted County, Minnesota, and developed appendicitis between 2006 and 2012 were matched to controls (1:1) with regard to birthday, gender, registration date, and index date. Asthma status was ascertained using predetermined criteria. Active (current) asthma was defined as the presence of asthma symptoms or asthma-related events (eg, medication use, clinic visits, emergency department, or hospitalization) within 1 year before the index date. Inactive asthma was defined as subjects without these events. A conditional logistic regression model was used.

RESULTS

Among the 309 appendicitis cases identified, when stratified according to asthma status, active asthma was associated with significantly increased risk of appendicitis compared with inactive asthma (odds ratio [OR] = 2.48; 95% confidence interval [CI], 1.22-5.03) and to no asthma (OR = 1.88; 95% CI, 1.07-3.27; overall P = .035). When controlling for potential confounders such as gender, age, and smoking status, active asthma was associated with a higher odds of developing appendicitis compared with nonasthmatic patients (adjusted OR = 1.75; 95% CI, 0.99-3.11) whereas inactive asthma was not (overall P = .049). Tobacco smoke exposure within 3 months was associated with an increased risk of appendicitis (adjusted OR = 1.66; 95% CI, 1.02-2.69). Among asthma medications, leukotriene receptor antagonists reduced the risk of appendicitis (OR = 0.18; 95% CI, 0.04-0.74).

CONCLUSIONS

Active asthma might be an unrecognized risk factor for appendicitis in children whereas a history of inactive asthma does not pose such risk. Further investigation exploring the underlying mechanisms is warranted.

The Cost-effectiveness of Varicella Zoster Virus Vaccination Considering Late Onset Asthma

BACKGROUND

Recent studies reported that infection by varicella zoster virus (VZV) may lead to delayed onset of asthma in children/adolescents. This information will likely alter the cost-effectiveness of the US. VZV vaccination program. We created a decision analysis model to estimate the costs and health-related effects of VZV 2-dose vaccination, assuming VZV infection delays asthma onset.

METHODS

The Markov model considered a birth cohort of 3,957,577 individuals entering the population from a societal perspective. We predicted the number of asthma/VZV cases, asthma-/VZV-related mortality and costs associated with asthma/VZV. Comparison arms included (1) VZV vaccination program without delayed asthma onset, (2) VZV vaccination program with delayed asthma onset and (3) no VZV vaccination program with delayed asthma onset. We considered delayed onset ranging from 3 to 12 years.

RESULTS

The vaccination program proved cost-effective without an assumed delay in asthma onset. When the vaccination and no-vaccination arms were compared assuming delayed asthma onset, vaccination remained less costly despite increased savings related to asthma without vaccination. With delayed asthma onset of 9 years post VZV infection, cost savings due to vaccination were $914.09 million, with 9984 cases of asthma averted and 9 greater overall deaths with vaccination.

CONCLUSION

VZV vaccination program was less costly than the "no-vaccination" scenario, despite delayed onset of asthma post VZV infection. However, vaccination resulted in increased asthma morbidity and mortality. This adds to current evidence that VZV vaccination is cost-effective, and may alter asthma-related health-care outcomes. VZV's effect on asthma symptoms still needs further evaluation before firm conclusions can be reached.

Adult asthma is associated with an increased risk of herpes zoster: A population-based cohort study

OBJECTIVE

The objective of this study was to determine whether a new diagnosis of asthma is associated with a later diagnosis of herpes zoster (HZ) in a nationwide, retrospective, non-age limited, population-based cohort.

METHODS

We used data from the National Health Insurance Research Database in Taiwan. The asthma group consisted of all 40 069 patients in the database with newly diagnosed asthma and using asthma medications from 2000 through 2005. The nonasthma group comprised 40 069 age- and sex-matched patients without any asthma diagnosis. Cox proportional hazards regression analysis was applied to calculate the hazard ratio of HZ in the patients with asthma relative to those without asthma.

RESULTS

During a mean follow-up period of 8.77 years, the risk of HZ was 1.48-fold higher in the asthma group compared with that in the nonasthma group after adjustment for sex, age, comorbidities, inhaled and systemic corticosteroid use, and annual outpatient department visits to dermatologists. Additional stratified analyses revealed that the risk of HZ was significantly higher in patients of both sexes and those aged older than 21 years.

CONCLUSIONS

Newly diagnosed adult patients with asthma have a significantly higher risk of developing HZ than do those without asthma.

Asthma and risk of breakthrough varicella infection in children

BACKGROUND

We recently reported a more rapid waning of vaccine-induced humoral immunity (measles vaccine) in children with asthma. It is unknown if asthma affects susceptibility to vaccine-preventable diseases.

OBJECTIVE

To determine whether asthma is associated with an increased risk of vaccine-preventable disease, e.g., breakthrough varicella infection.

METHODS

This was a retrospective population-based case-control study that examined cases of breakthrough varicella among children between 2005 and 2011. Children with a diagnosis of breakthrough varicella infection in Olmsted County, Minnesota (infection of >42 days after vaccination) between 2005 and 2011 and two age- and sex-matched controls were enrolled for each case. Asthma status was determined by using predetermined criteria. Conditional logistic regression models were used to calculate matched odds ratios (OR) and their corresponding 95% confidence intervals (CI).

RESULTS

Of the 165 cases and their 330 matched controls, 48% were boys and the mean (standard deviation) age at the index date was 6.6 ± 3.5 years for both cases and controls. Of the 330 controls, 80 (24%) had two doses of the varicella vaccine compared with only 23 (14%) of the 165 cases (OR 0.29 [95% CI, 0.14-0.61]; p = 0.001). Children with a history of asthma ever had a higher risk of developing breakthrough varicella compared with those without a history of asthma (adjusted OR 1.63 [95% CI, 1.04-2.55]; p = 0.032) when adjusting for elapsed time since the first varicella vaccination and the number of varicella vaccine doses.

CONCLUSIONS

A history of asthma might be an unrecognized risk factor for breakthrough varicella infection. Children with asthma should follow the two-dose varicella vaccine policy.

Asthma as a risk factor for zoster in adults: A population-based case-control study

BACKGROUND

We recently reported an increased risk of herpes zoster (shingles or zoster) in children with asthma, but little is known about whether the same is true for adults with asthma.

OBJECTIVE

We determined whether asthma is associated with an increased risk of zoster in adults.

METHODS

This study was designed as a population-based case-control study. Zoster cases during the study period were identified among adults (aged ≥50 years) who resided in Olmsted County, Minnesota. We compared the frequency of asthma between zoster cases and birthday- and sex-matched control subjects (1:2 matching) without a history of zoster. Asthma status was ascertained based on predetermined criteria. A conditional logistic regression model was used to assess the association of asthma with risk of zoster.

RESULTS

A total of 371 zoster cases and their 742 matched control subjects were enrolled. Of the 371 cases, 246 (66%) were female, 348 (94%) were white, and the mean ± SD age was 66.8 ± 10.7 years. Twenty-three percent (n = 87) of zoster cases had a history of asthma compared with 15% (n = 114) of control subjects. Controlling for pertinent covariates and confounders, there was a significant association between a history of asthma and risk of zoster (adjusted odds ratio, 1.70; 95% CI, 1.20-2.42; P = .003). The population attributable risk percentage for asthma was about 10%.

CONCLUSIONS

Asthma is an unrecognized risk factor for zoster in adults. Consideration should be given to immunizing adults with asthma aged more than 50 years as a target group.

Risk of herpes zoster in children with asthma

BACKGROUND

There is literature that indicates the association of asthma with an increased risk of common and serious microbial infections. We recently reported an increased risk of vaccine-preventable diseases, e.g., herpes zoster (HZ) among children with asthma, defined by predetermined asthma criteria. Little is known about whether this association is persistent if the asthma status is defined by different asthma criteria, e.g., the Asthma Predictive Index, given the heterogeneity of asthma.

OBJECTIVE

To assess the consistency of the association between asthma and the risk of HZ in children.

METHODS

This is a population-based case-control study based on all pediatric patients with HZ between 1996 and 2001 in Olmsted County, Minnesota, and 1:1 age- and sex-matched controls without a history of HZ who were enrolled in our previous study. The original Asthma Predictive Index criteria was operationalized by two or more wheezing episodes in a year for the first 3 years of life plus one of the major (physician-diagnosed asthma for a parent or physician-diagnosed eczema for a patient) or two of the minor criteria (physician-diagnosed allergic rhinitis for a patient, wheezing apart from cold, or eosinophilia [≥4%]). Data were fit to traditional logistic regression models to calculate odds ratios and 95% confident intervals.

RESULTS

Of the original cohort (n = 554), 95 (17%) did not meet the enrollment criteria for this study, which left 459. Of the 221 patients, 53% were female, with a mean (standard deviation) age of 9.7 ± 4.2 years. The risk of HZ was increased in children with asthma defined by the API controlling for a varicella vaccine history and atopic status (adjusted odds ratio 2.56 [95% confidence interval, 1.08-6.56]).

CONCLUSIONS

The association between asthma and increased risk of HZ in children and adolescents is consistent, independent of asthma definitions. Asthma might be an important clinical condition to be considered in HZ vaccine studies.

Asthma-associated comorbidities in children with and without secondhand smoke exposure

BACKGROUND

Secondhand smoke (SHS) exposure is known to trigger asthma, but asthma disease severity and comorbidities in children exposed to SHS are not very well quantified.

OBJECTIVE

To identify comorbidities and understand health care usage in children with asthma exposed to SHS (cases) compared with children with asthma but without SHS exposure (controls).

METHODS

A retrospective nested matched case-and-control study was conducted with children 5 to 18 years old who were enrolled in the Pediatric Asthma Management Program. Pulmonary function testing (spirometry, methacholine challenges, and exhaled nitric oxide) and body mass index were reviewed. Influenza vaccination rates, oral steroid usage, emergency department visits, and hospitalizations were assessed. Network analysis of the 2 groups also was conducted to evaluate for any associations between the variables.

RESULTS

Cases had significantly higher body mass index percentiles (>75%, odds ratio [OR] 1.64, 95% confidence interval [CI] 1.22-2.2, P = .001). Cases were less likely to have had a methacholine challenge (OR 0.49, 95% CI 0.36-0.68, P < .001) and an exhaled nitric oxide (OR 0.6, 95% CI 0.37-0.97, P = .04) performed than controls. The ratio of forced expiration volume in 1 second to forced vital capacity and forced expiration volume in 1 second were lower in cases than in controls (P < .05). Cases were less likely to have received an influenza vaccination (OR 0.61, 95% CI 0.45-0.82, P = .001) than controls. Unsupervised multivariable network analysis suggested a lack of discrete and unique subgroups between cases and controls.

CONCLUSION

Children with asthma exposed to SHS are more likely to have comorbid conditions such as obesity, more severe asthma, and less health care usage than those not exposed to SHS. Smoking cessation interventions and addressing health disparities could be crucial in this vulnerable population.

Varicella zoster virus infection

Infection with varicella zoster virus (VZV) causes varicella (chickenpox), which can be severe in immunocompromised individuals, infants and adults. Primary infection is followed by latency in ganglionic neurons. During this period, no virus particles are produced and no obvious neuronal damage occurs. Reactivation of the virus leads to virus replication, which causes zoster (shingles) in tissues innervated by the involved neurons, inflammation and cell death - a process that can lead to persistent radicular pain (postherpetic neuralgia). The pathogenesis of postherpetic neuralgia is unknown and it is difficult to treat. Furthermore, other zoster complications can develop, including myelitis, cranial nerve palsies, meningitis, stroke (vasculopathy), retinitis, and gastroenterological infections such as ulcers, pancreatitis and hepatitis. VZV is the only human herpesvirus for which highly effective vaccines are available. After varicella or vaccination, both wild-type and vaccine-type VZV establish latency, and long-term immunity to varicella develops. However, immunity does not protect against reactivation. Thus, two vaccines are used: one to prevent varicella and one to prevent zoster. In this Primer we discuss the pathogenesis, diagnosis, treatment, and prevention of VZV infections, with an emphasis on the molecular events that regulate these diseases. For an illustrated summary of this Primer, visit: http://go.nature.com/14xVI1.

Herpes zoster is associated with herpes simplex and other infections in under 60 year-olds

OBJECTIVES

We assessed the association between herpes zoster (HZ) and herpes simplex (HS) occurrence whilst controlling for risk factors of HZ.

METHODS

Using a Belgian general practitioner network, a retrospective cohort study with 3736 HZ patients and 14,076 age-gender-practice matched controls was performed, covering over 1.5 million patient-years. Multiple logistic regression was used with HZ as outcome and several diagnoses (malignancy, depression, diabetes mellitus, auto-immune diseases, asthma, multiple sclerosis, HIV, fractures), medications (systemic corticosteroids, biologicals, vaccination), HS and other infections as variables.

RESULTS

HS was significantly associated with HZ for all analysed time intervals (up to five years) post HZ (OR of 3.51 [2.09 5.88] 95%CI one year post HZ) and to a lesser extent for time ranges pre HZ. Registration of other infections was significantly associated with HZ in all time intervals pre and post HZ (OR up to 1.37). Malignancy up to five years pre HZ, depression up to one year pre or post HZ, fractures up to two years pre HZ, asthma, auto-immune diseases, and immunosuppressive medication one year pre or post HZ were also associated with HZ.

CONCLUSIONS

HZ and HS occurrences are significantly associated and potentially share a common susceptibility beyond the known risk factors.

Development and initial testing of Asthma Predictive Index for a retrospective study: an exploratory study

OBJECTIVE

Asthma Predictive Index (API) has been used for predicting asthma in prospective or cross-sectional studies, not for a retrospective study. We aim to develop and validate API for a retrospective study.

METHODS

This is a cross-sectional study based on a convenience sample of children who participated in a previous retrospective cohort study. API was operationalized by two or more wheezing episodes in a year during the first 3 years of life PLUS one of the major or two of the minor criteria of the original API. We assessed validity of retrospective API against Predetermined Asthma Criteria (PAC) which has been extensively used in clinical studies for asthma. We assessed criterion validity by measuring kappa and agreement rate between API and PAC and construct validity by determining associations of API with known risk factors for asthma.

RESULTS

Of the eligible 105 children, 55 (52.4%) were male, 90 (85.7%) Caucasians, and the mean age (±SD) was 5.8 years (±1.5). API criteria was met by 15 (14.3%), compared to 33 (31.4%) by PAC, respectively. The agreement rate and kappa between API and definite asthma of PAC were 89.5% and 0.66 (p < 0.01). Atopic conditions, lower parental education, no history of breastfeeding and family history of asthma were significantly associated with risk of asthma by API.

CONCLUSIONS

Application of API to a retrospective study for ascertaining asthma status is suitable. Our study findings need to be replicated by future studies with a larger sample size.

Risks for infection in patients with asthma (or other atopic conditions): is asthma more than a chronic airway disease?

Most of the research effort regarding asthma has been devoted to its causes, therapy, and prognosis. There is also evidence that the presence of asthma can influence patients' susceptibility to infections, yet research in this aspect of asthma has been limited. There is additional debate in this field, with current literature tending to view the increased risk of infection among atopic patients as caused by opportunistic infections secondary to airway inflammation, especially in patients with severe atopic diseases. However, other evidence suggests that such risk and its underlying immune dysfunction might be a phenotypic or clinical feature of atopic conditions. This review argues (1) that improved understanding of the effects of asthma or other atopic conditions on the risk of microbial infections will bring important and new perspectives to clinical practice, research, and public health concerning atopic conditions and (2) that research efforts into the causes and effects of asthma must be juxtaposed because they are likely to guide each other.

Quantification of risk factors for herpes zoster: population based case-control study

OBJECTIVES

To quantify the effects of possible risk factors for herpes zoster at different ages.

DESIGN

Case-control study.

SETTING

UK Clinical Practice Research Datalink primary care data.

PARTICIPANTS

144 959 adults diagnosed with zoster between 2000 and 2011; 549,336 age, sex, and practice matched controls.

MAIN OUTCOME MEASURES

Conditional logistic regression was used to generate adjusted odds ratios to estimate the strength of association of each potential risk factor with zoster and assess effect modification by age.

RESULTS

The median age of the cases and controls was 62 years. Factors associated with increased risk of zoster included rheumatoid arthritis (3111 (2.1%) v 8029 (1.5%); adjusted odds ratio 1.46, 99% confidence interval 1.38 to 1.55), inflammatory bowel disease (1851 (1.3%) v 5118 (0.9%); 1.36, 1.26 to 1.46), chronic obstructive pulmonary disease (6815 (4.7%) v 20 201 (3.7%); 1.32, 1.27 to 1.37), asthma (10 243 (7.1%) v 31 865 (5.8%); 1.21, 1.17 to 1.25), chronic kidney disease (8724 (6.0%) v 29 437 (5.4%); 1.14, 1.09 to 1.18), and depression (6830 (4.7%) v 22 052 (4.0%); 1.15, 1.10 to 1.20). Type 1, but not type 2, diabetes showed some association with zoster (adjusted odds ratio 1.27, 1.07 to 1.50). The relative effects of many assessed risk factors were larger in younger patients. Patients with severely immunosuppressive conditions were at greatest risk of zoster-for example, patients with lymphoma (adjusted odds ratio 3.90, 3.21 to 4.74) and myeloma (2.16, 1.84 to 2.53), who are not eligible for zoster vaccination.

CONCLUSIONS

A range of conditions were associated with increased risk of zoster. In general, the increased risk was proportionally greater in younger age groups. Current vaccines are contraindicated in people at the greatest risk of zoster, highlighting the need for alternative risk reduction strategies in these groups.

Sociodemographic characteristics and chronic medical conditions as risk factors for herpes zoster: a population-based study from primary care in Madrid (Spain)

The objectives of this study were to estimate incidence density rates (IDR) of herpes zoster (HZ) and to analyze the association with sociodemographic characteristics and selected chronic medical conditions. The study cohort consisted of the adult population included in the Public Health System of the Autonomous Community of Madrid, Spain on 1/10/2009 (5 244 402 persons). Data source were electronic medical records from primary care between 1/10/2009-31/12/2012. Individual socioeconomic status (SES) was inferred by geocoding. Poisson regression analyses were stratified by sex, to identify factors associated with HZ. We identified 81 541 incident cases of HZ (61.7% in women and 46.5% in the group aged 60 and over). IDR was 4.11 per 1000 person-years in men and 5.95 in women. IDR were higher with age, in autochthonous population, those with lower SES and in patients with immunodeficiencies. After adjustment, higher incidence rate ratios were found with age, autochthonous origin, lower SES, and in patients with HIV-infection/AIDS (3.20, CI95% 2.90-3.53 in men and 2.98, CI95% 2.58-3.45 in women), and other immunodeficiencies (1.57, CI95% 1.41-1.75 and 1.65, CI95% 1.50-1.80). COPD, asthma, DM, ischemic heart disease, other cardiovascular diseases, and cancer were also associated with an increased incidence of HZ. We conclude that older, autochthonous patients with lower SES and with certain underlying medical conditions had a higher probability of suffering HZ. Electronic databases are useful for estimating the incidence of HZ, and for finding associations with sociodemographic and clinical characteristics. Identifying unrecognized risk factors for HZ, such as asthma or cardiovascular diseases, is crucial to interpret the epidemiology of HZ, to target vaccination programs and to monitor their effect.