Active or Passive Exposure to Tobacco Smoking and Allergic Rhinitis, Allergic Dermatitis, and Food Allergy in Adults and Children: A Systematic Review and Meta-Analysis
Allergic rhinitis, allergic dermatitis, and food allergy are extremely common diseases, especially among children, and are frequently associated to each other and to asthma. Smoking is a potential risk factor for these conditions, but so far, results from individual studies have been conflicting. The objective of this study was to examine the evidence for an association between active smoking (AS) or passive exposure to secondhand smoke and allergic conditions.
Methods and Findings
We retrieved studies published in any language up to June 30th, 2013 by systematically searching Medline, Embase, the five regional bibliographic databases of the World Health Organization, and ISI-Proceedings databases, by manually examining the references of the original articles and reviews retrieved, and by establishing personal contact with clinical researchers. We included cohort, case-control, and cross-sectional studies reporting odds ratio (OR) or relative risk (RR) estimates and confidence intervals of smoking and allergic conditions, first among the general population and then among children.
We retrieved 97 studies on allergic rhinitis, 91 on allergic dermatitis, and eight on food allergy published in 139 different articles. When all studies were analyzed together (showing random effects model results and pooled ORs expressed as RR), allergic rhinitis was not associated with active smoking (pooled RR, 1.02 [95% CI 0.92–1.15]), but was associated with passive smoking (pooled RR 1.10 [95% CI 1.06–1.15]). Allergic dermatitis was associated with both active (pooled RR, 1.21 [95% CI 1.14–1.29]) and passive smoking (pooled RR, 1.07 [95% CI 1.03–1.12]). In children and adolescent, allergic rhinitis was associated with active (pooled RR, 1.40 (95% CI 1.24–1.59) and passive smoking (pooled RR, 1.09 [95% CI 1.04–1.14]). Allergic dermatitis was associated with active (pooled RR, 1.36 [95% CI 1.17–1.46]) and passive smoking (pooled RR, 1.06 [95% CI 1.01–1.11]). Food allergy was associated with SHS (1.43 [1.12–1.83]) when cohort studies only were examined, but not when all studies were combined.
The findings are limited by the potential for confounding and bias given that most of the individual studies used a cross-sectional design. Furthermore, the studies showed a high degree of heterogeneity and the exposure and outcome measures were assessed by self-report, which may increase the potential for misclassification.
We observed very modest associations between smoking and some allergic diseases among adults. Among children and adolescents, both active and passive exposure to SHS were associated with a modest increased risk for allergic diseases, and passive smoking was associated with an increased risk for food allergy. Additional studies with detailed measurement of exposure and better case definition are needed to further explore the role of smoking in allergic diseases.
US prevalence of self-reported peanut, tree nut, and sesame allergy: 11-year follow-up
Source: Journal of Allergy and Clinical Immunology
Allergy to peanuts and tree nuts (TNs) is the leading cause of fatal allergic reactions in the United States, and the prevalence appears to be increasing.
We sought to determine the US prevalence of self-reported peanut, TN, and sesame allergy in 2008 and compare results with comparable surveys conducted in 1997 and 2002.
A nationwide, cross-sectional, random telephone survey for peanut and TN allergy was conducted with a previously used questionnaire, with additional questions about sesame.
A total of 5,300 households (13,534 subjects) were surveyed (participation rate, 42% vs 52% in 2002 and 67% in 1997). Peanut allergy, TN allergy, or both was reported by 1.4% of subjects (95% CI, 1.2% to 1.6%) compared with 1.2% in 2002 and 1.4% in 1997. For adults, the prevalence was 1.3% (95% CI, 1.1% to 1.6%), which was not significantly different from prior surveys. However, the prevalence of peanut or TN allergy for children younger than 18 years was 2.1% (95% CI, 1.6% to 2.7%) compared with 1.2% in 2002 (P = .007) and 0.6% in 1997 (P < .001). The prevalence of peanut allergy in children in 2008 was 1.4% (95% CI, 1.0% to 1.9%) compared with 0.8% in 2002 (P = not significant) and 0.4% in 1997 (P 3 million subjects) and appear to be increasingly reported among children over the past decade. Sesame allergy is reported much less commonly.
Prospective Study of Peripregnancy Consumption of Peanuts or Tree Nuts by Mothers and the Risk of Peanut or Tree Nut Allergy in Their Offspring
The etiology of the increasing childhood prevalence of peanut or tree nut (P/TN) allergy is unknown.
To examine the association between peripregnancy consumption of P/TN by mothers and the risk of P/TN allergy in their offspring.
Design, Setting, and Participants
Prospective cohort study. The 10 907 participants in the Growing Up Today Study 2, born between January 1, 1990, and December 31, 1994, are the offspring of women who previously reported their diet during, or shortly before or after, their pregnancy with this child as part of the ongoing Nurses’ Health Study II. In 2006, the offspring reported physician-diagnosed food allergy. Mothers were asked to confirm the diagnosis and to provide available medical records and allergy test results. Two board-certified pediatricians, including a board-certified allergist/immunologist, independently reviewed each potential case and assigned a confirmation code (eg, likely food allergy) to each case. Unadjusted and multivariable logistic regression analyses were used to evaluate associations between peripregnancy consumption of P/TN by mothers and incident P/TN allergy in their offspring.
Peripregnancy consumption of P/TN.
Main Outcomes and Measures
Physician-diagnosed P/TN allergy in offspring.
Among 8205 children, we identified 308 cases of food allergy (any food), including 140 cases of P/TN allergy. The incidence of P/TN allergy in the offspring was significantly lower among children of the 8059 nonallergic mothers who consumed more P/TN in their peripregnancy diet (≥5 times vs <1 time per month: odds ratio = 0.31; 95% CI, 0.13-0.75; Ptrend = .004). By contrast, a nonsignificant positive association was observed between maternal peripregnancy P/TN consumption and risk of P/TN allergy in the offspring of 146 P/TN-allergic mothers (Ptrend = .12). The interaction between maternal peripregnancy P/TN consumption and maternal P/TN allergy status was statistically significant (Pinteraction = .004).
Conclusions and Relevance
Among mothers without P/TN allergy, higher peripregnancy consumption of P/TN was associated with lower risk of P/TN allergy in their offspring. Our study supports the hypothesis that early allergen exposure increases tolerance and lowers risk of childhood food allergy.
Treatments for Seasonal Allergic Rhinitis
Source: Agency for Healthcare Research and Quality
This review compared the effectiveness and common adverse events of medication classes used to treat seasonal allergic rhinitis (SAR) in adolescents and adults, in pregnant women, and in children. We sought to compare the following classes of drugs: oral and nasal antihistamines and decongestants; intranasal corticosteroids, mast cell stabilizers (cromolyn), and anticholinergics (ipratropium); oral leukotriene receptor antagonists (montelukast); and nasal saline.
We identified English-language studies using a peer-reviewed search strategy. The following databases were
searched on July 18, 2012, with no date restrictions: MEDLINE® (PubMed® and Ovid), Embase® (Ovid), Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews, and DARE (Database of Abstracts of Reviews of Effects).
We consulted a Technical Expert Panel to identify the treatment comparisons most relevant to patients and providers. Subpopulations of interest were individuals with asthma or eye symptoms. Outcomes of interest were patient-reported symptom scores, quality of life, and adverse events. Inclusion was limited to studies that reported an outcome of interest and directly compared drugs of interest that were approved by the U.S. Food and Drug Administration (FDA). Two independent reviewers performed study selection and data abstraction. Disagreements were resolved by consensus or a third reviewer.
We identified 59 trials that addressed 13 of 22 treatment comparisons of interest for adolescents and adults, 0 of 17 comparisons of interest for pregnant women, and 1 of 21 comparisons of interest for children. Across all comparisons, 20 of 39 drugs FDA approved for the treatment of SAR were studied. For adolescents and adults with SAR, evidence was sufficient to form the following conclusions. For the treatment of nasal symptoms, montelukast (oral leukotriene receptor antagonist) and intranasal corticosteroid were similarly effective (high strength of evidence [SOE]). For the treatment of nasal symptoms and eye symptoms, intranasal corticosteroid, nasal antihistamine, and combination intranasal corticosteroid plus nasal antihistamine were similarly effective (high SOE), and montelukast and oral selective antihistamine were similarly effective (moderate SOE). For improved quality of life, montelukast and oral selective antihistamine were similarly effective (moderate SOE), and combination oral selective antihistamine plus intranasal corticosteroid was superior to oral selective antihistamine alone (low SOE). To avoid insomnia, oral selective antihistamine was superior to oral decongestant and to combination oral selective antihistamine plus oral decongestant (moderate SOE). In patients codiagnosed with SAR and asthma, montelukast was superior to oral selective antihistamine for reduced asthma rescue medication use (moderate SOE). In sensitivity analyses using a lower threshold for minimum clinical effectiveness, combination oral selective antihistamine plus oral decongestant was superior to oral selective antihistamine alone for the treatment of nasal symptoms in adolescents and adults with SAR (moderate SOE). In this population, we did not find evidence that any single treatment was both more effective and had lower risk of harms. Evidence for both effectiveness and harms was insufficient regarding the comparison between oral selective and oral nonselective antihistamine in children. All effectiveness and harms outcomes were limited by short trial durations.
Several effectiveness comparisons demonstrated similarity of treatments for selected outcomes. For most harms comparisons, the evidence was insufficient. Conclusions were limited by (1) lack of comparative evidence for all drugs within each class and (2) lack of evidence on the magnitude of symptom change that constitutes a minimal clinically important difference.
Source: National Center for Complementary and Alternative Medicine
Seasonal allergies, also called “hay fever,” are a common chronic medical problem. At least 17.7 million American adults (7.8 percent of the adult population) and 7 million children (about 9 percent of children) have seasonal allergies.
People manage seasonal allergies by taking medication, avoiding exposure to the substances that trigger their allergic reactions, having a series of “allergy shots” (a form of immunotherapy) or using various complementary approaches. According to the 2007 National Health Interview Survey, “respiratory allergy” is among the 15 conditions for which children in the United States use complementary approaches most frequently. This issue of the Digest provides information on what the science says about several complementary health approaches for seasonal allergies, such as saline nasal irrigation, butterbur, honey, acupuncture, and other practices.
Allergen-Specific Immunotherapy for the Treatment of Allergic Rhinoconjunctivitis and/or Asthma: Comparative Effectiveness Review
Source: Agency for Healthcare Research and Quality
Allergic rhinitis is highly prevalent in North America, affecting 20 to 40 percent of the population. Nearly 9 percent of Americans suffer from asthma, with more than half having evidence of atopy. This comparative effectiveness review describes the effectiveness and safety of subcutaneous immunotherapy and sublingual immunotherapy (off-label use of subcutaneousaqueous allergens for sublingual desensitization) compared with other therapies for treatment of allergic rhinoconjunctivitis and asthma.
We searched the MEDLINE® , Embase, LILACS, and CENTRAL databases from the beginning of each database through May 21, 2012.
Two reviewers independently selected randomized controlled trials according to established study inclusion criteria. Disagreements were resolved by consensus. Paired reviewers assessed the risk of bias of each study and extracted details about the population, intervention(s), and outcomes of interest. The results were summarized by immunotherapy type (sublingual or subcutaneous), allergen, and outcomes. Studies exclusively enrolling children were reviewed separately. The strength of the body of evidence was graded and summarized.
We included 74 references that investigated the efficacy and safety of subcutaneous immunotherapy, 60 studies that investigated the efficacy and safety of sublingual immunotherapy, and 8 studies that compared the two modes of delivery. All 142 studies were randomized controlled studies. The majority of studies were at medium risk of bias due to design choices. The strength of evidence is high that subcutaneous immunotherapy reduces asthma symptoms, rhinitis symptoms, conjunctivitis symptoms, asthma medication use, asthma plus rhinoconjunctivitis medication use, and rhinoconjunctivitis-specific quality of life. The strength of evidence is moderate that subcutaneous immunotherapy reduces rhinoconjunctivitis medication use, relative to usual care, which includes pharmacotherapy. Likewise, the strength of evidence is high that sublingual immunotherapy reduces asthma symptoms. The strength of evidence is moderate that sublingual immunotherapy reduces rhinitis/rhinoconjunctivitis symptoms, combined symptom scores, conjunctivitis symptoms, and medication useusage relative to usual care, and improves allergy-specific quality of life. In studies comparing subcutaneous with sublingual immunotherapy, strength of evidence supporting the superiority of subcutaneous immunotherapy for reducing allergic rhinitis and conjunctivitis symptoms, and the superiority of sublingual immunotherapy for reducing medication use, is low. We identified 13 pediatric studies of subcutaneous immunotherapy, 18 pediatric studies of sublingual immunotherapy, and 3 pediatric studies comparing subcutaneous and sublingual immunotherapy. The strength of evidence is moderate that subcutaneous immunotherapy reduces asthma symptoms and rhinitis symptoms in comparison to usual care. The strength of evidence is low that subcutaneous immunotherapy reduces conjunctivitis symptoms, medication scores, combined symptom-medication scores, or improves quality of life relative to usual care. The strength of evidence is high that sublingual immunotherapy reduces asthma symptoms, and moderate that it reduces rhinitis/rhinoconjunctivitis symptoms, combined asthma plus rhinitis/rhinoconjunctivitis symptoms, conjunctivitis symptoms, and decreases medication use. While local reactions were frequent with both treatment regimens, there were rare reports of anaphylaxis in the subcutaneous immunotherapy studies, and no anaphylaxis reported in the sublingual immunotherapy studies.
With some variation across outcomes, the overall body of evidence consistently provides moderate to high support for the effectiveness and safety of both subcutaneous and sublingual immunotherapy for the treatment of allergic rhinitis and asthma. The evidence to support the use of immunotherapy in children is somewhat weaker than the evidence supporting its use in adults. The superiority of one route of administration over the other is not known.
Source: U.S. Food and Drug Administration
Little teapots with long spouts have become a fixture in many homes for reasons that have nothing to do with tea.
Called neti pots, they are used to rinse the nasal passages with a saline (salt-based) solution, and have become popular as a treatment for congested sinuses, colds and allergies, and for moistening nasal passages exposed to dry indoor air.
However, the Food and Drug Administration (FDA) has concerns about the risk of infection tied to the improper use of neti pots and other nasal rinsing devices. The agency is informing consumers, manufacturers and health care professionals about safe practices for using all nasal rinsing devices, which include bulb syringes, squeeze bottles, and battery-operated pulsed water devices.
These devices are generally safe and useful products, says Steven Osborne, M.D., a medical officer in FDA’s Center for Devices and Radiological Health (CDRH). But they must be used and cleaned properly.
Most important is the source of water that is used with nasal rinsing devices. Tap water that is not filtered, treated, or processed in specific ways is not safe for use as a nasal rinse.
The burden of allergic rhinitis (AR) in Canada: perspectives of physicians and patients
Source: Allergy, Asthma & Clinical Immunology
Allergic rhinitis (AR) is a common problem and we sought to examine the burden of disease and its management in Canada from the perspectives of patients and physicians.
Two parallel, Canadawide structured telephone interviews surveyed 1,001 AR patients and 160 physicians in July 2006.
44% of patients had experienced nasal symptoms unrelated to a cold and 20% had a physician diagnosis of AR. At screening 27% reported asthma, 15% chronic or recurrent sinusitis and 5% nasal polyps. With attacks nasal congestion and runny nose were the most bothersome symptoms. Other problems experienced were fatigue (46%), poor concentration (32%), and reduced productivity (23%). Most (77%) had not seen a physician in the past year. Physicians estimated they prescribed intranasal cortico steroids (INCS) to most AR patients (77%) consistent with guidelines but only 19% of patients had used one in the last month. Only 48% of patients were very satisfied with their current INCS. 41% of AR patients reported discontinuing their INCS with the most common reason being a perceived lack of long-lasting symptom relief (44%). 52% of patients felt that their current INCS lost effectiveness over 24 h. The most common INCS side effects included dripping down the throat, bad taste, and dryness. Most AR patients reported lifestyle limitations despite treatment (66%). 61% of patients felt that their symptoms were only somewhat controlled or poorly/not controlled during their worst month in the past year.
AR symptoms are common and many patients experience inadequate control. Physicians report they commonly prescribe intranasal corticosteroids, but patient’s perceived loss of efficacy and side effects lead to their discontinuation. Persistent relief of allergic rhinitis symptoms remains a major unmet need. Better treatments and education are required.
Food allergy knowledge, attitudes, and beliefs in the United States (PDF)
Source: Annals of Allergy, Asthma & Immunology
Increased food allergy knowledge among the general public is needed. Improved public awareness of the challenges faced by food-allergic children may encourage adoption of standardized school policies to keep affected children safe. These efforts are critical for protecting young children with food allergy and avoiding life-threatening anaphylactic reactions.