What Evidence-based Medicine (EBM) Doesn't Say About Allergen-specific Immunotherapy (AIT).

Evidence-based allergology for the treatment of allergic rhinitis with allergen-specific immunotherapy (AIT) has been used in publications by the companies manufacturing AIT. The purpose of randomized controlled trials (RCTs) is to provide physicians, health authorities, patients, and their families with the best evidence upon which to base treatment decisions. However, some RCT results may do more harm than good because they serve the commercial interests of the companies producing and marketing AIT more than the interests of patients. Allergic rhinitis is a trivial disease that is not life-threatening and is easily controlled by drugs. In this paper, we analyze some of the more controversial points underlying the EBM supporting the use of AIT. The paradox behind RCT-based practice is that AIT is based on the results of incorrectly interpreted RCTs. International scientific societies and drug regulatory bodies should analyze trials more carefully, considering potential conflicts of interest.

Allergic Diseases in the Elderly.

Recent increases in allergic diseases are thought to be caused by better hygiene, Westernized diets, air pollution, climate change, and other factors that influence host microbiota, a key player in the induction and maintenance of immunoregulatory circuits and tolerance. The increase of allergic diseases in the elderly is also related to additional factors, such as various comorbidities that may interfere with the development and the type of allergic reactions. Immunosenescence plays a central role in these reactions, altering microbiota responses and triggering inflammageing. In addition, in the elderly, there is a shift from Th1 to Th2 immunity, thus favoring allergic responses. A better understanding of the mechanisms responsible for immunosenescence and its effects on allergic inflammation will most certainly lead to improved therapies.

Efficacy and safety of allergen immunotherapy in patients with allergy to molds: A systematic review.

BACKGROUND: Allergen immunotherapy (AIT) with mould extracts has been performed for many years but the final demonstration of its clinical efficacy is still missing, due to the small number of studies and their inconsistent results. OBJECTIVE: To systematically review efficacy and safety of AIT for the treatment of respiratory allergies to moulds. DESIGN: The primary outcomes were safety and reduction of symptoms (Symptom Score, SS) and medication use (Medication Score, MS) in patients treated with AIT compared to controls. The strength of the evidence was graded based on the risk of bias, consistency and magnitude of effect, according to the GRADE Working Group's guide. DATA SOURCES: Medline, Web of Science and the Cochrane Library (through September 2017) supplemented with manual searches of reference lists. ELIGIBILITY CRITERIA: Randomized studies of intervention comparing AIT to placebo/pharmacotherapy. Studies not reporting on our outcome of interest or without a control population were excluded. RESULTS: Nine studies (168 children, 99 adults; median sample size, 27) met the inclusion criteria. The risk of bias was moderate-to-high in all but one study. Low strength evidence supports the assumption that AIT is effective in reducing symptoms and medication use, with only four of nine studies reporting higher benefit of AIT vs. comparators. The highest benefit of AIT compared to pharmacotherapy/placebo was reported in studies with a longer follow-up (SMD for MS from -3.96 to -3.97 in favour of AIT) and low risk of bias (VAS for SS: 66.3 ± 13 in AIT group; 186.6 ± 39 in comparators; P < 0.05). No difference was reported with respect to study sample size, route of administration, age of participants. Generalised adverse reactions were reported in 12.5% of participants treated with sublingual immunotherapy, and 37.2% of participants treated with subcutaneous immunotherapy. CONCLUSIONS: Low strength evidence suggests that mould AIT is efficacious for the treatment of respiratory allergies. High-quality studies with an adequate sample size are needed.

The effect of allergen immunotherapy in the onset of new sensitizations: a meta-analysis.

BACKGROUND: Although the preventive efficacy of allergen immunotherapy (AIT) in the onset of new allergen sensitizations has been asserted by many reviews, position papers, and consensus conferences, the evidence available is from only 3 studies. The objective of this work was a systematic review to evaluate the preventive efficacy of AIT in the onset of new allergen sensitizations. The end-point was the risk difference (RD) in the onset of new allergen sensitizations between patients treated with AIT and pharmacotherapy. METHODS: Computerized bibliographic searches of MEDLINE, EMBASE, and the Cochrane Library (until November 30th, 2016) were done. Random-effects and fixed-effects model meta-analyses were performed. Randomized controlled trials or observational studies comparing children treated with AIT with house dust mite (HDM) to subjects who did not receive AIT, with a long-term observation period (at least 3 years including treatment and follow-up) have been included. RESULTS: Eight studies totaling 721 children (390 treated with AIT and 331 with pharmacotherapy) met the inclusion criteria. The risk of bias was high. Low evidence supports the conclusion that AIT prevents the onset of new allergen sensitizations, with 3 of 8 studies reporting a reduction in the onset of new sensitizations in patients treated with AIT vs pharmacotherapy. Our meta-analysis found no difference between AIT and pharmacotherapy, with high heterogeneity (RD, -0.10; 95% confidence interval [CI], -0.31 to 0.11; p = 0.32; I2 = 91.4%). CONCLUSION: The data of this systematic review do not support a preventive effect in the onset of new allergen sensitizations, in children treated with AIT in comparison with those treated with pharmacotherapy.

How to fit allergen immunotherapy in the elderly.

Asthma, allergic rhinitis (AR) and atopic dermatitis are very common in young people, but in the latest decades it was increasingly recognized that also individuals of higher ages, including the population over 65 years, are concerned. Actually, it is now acknowledged the aging does not considerably alter the immune response to allergens. Allergen immunotherapy (AIT) is the only treatment that works on the causes of allergy, but elderly people are commonly excluded from AIT, except the cases of insect sting allergy. A number of recent studies showed that aged individuals also successfully respond to AIT for respiratory allergy. Therefore, there is no reason to exclude elder patients from AIT. Anyhow, clinical conditions that are considered absolute or relative contraindications are quite frequent in this aged population, thus the risk/benefit ratio must be carefully evaluated for each patient, taking into account that the more frequent occurrence of co-morbidities and the consequent need of daily-based multidrug regimen can favor adverse effects. An important issue concern the ability of AIT, and particularly of sublingual immunotherapy, to significantly improve the quality of life, that often is particularly impaired in the elderly, reducing symptoms and drugs consumption.

Immunological and non-immunological mechanisms of allergic diseases in the elderly: biological and clinical characteristics.

A better hygiene, a Westernized diet, air pollution, climate changes, and other factors that influence host microbiota, a key player in the induction and maintenance of immunoregulatory circuits and tolerance, are thought to be responsible for the increase of allergic diseases observed in the last years. The increase of allergic diseases in elderly is related to the presence of other factors as several comorbidities that should interfere with the development and the type of allergic reactions. A central role is played by immunosenescence responsible for modifying response to microbiota and triggering inflamm-ageing. In addition, in elderly there is a shift from Th1 responses vs. Th2, hence favouring allergic responses. Better understanding of the mechanisms of immunosenescence and its effects on allergic inflammation will most certainly lead to improved therapy.

Efficacy of Grass Pollen Allergen Sublingual Immunotherapy Tablets for Seasonal Allergic Rhinoconjunctivitis: A Systematic Review and Meta-analysis.

IMPORTANCE: Randomized clinical trials (RCTs) and meta-analyses of sublingual immunotherapy (SLIT) for the treatment of seasonal allergic rhinoconjunctivitis (SARC) have shown a modest clinical benefit compared with placebo. Furthermore, indirect comparison by meta-analyses showed that subcutaneous immunotherapy is more effective than SLIT. Despite these data, SLIT has become the most prescribed treatment of SARC in Europe in recent years, and it was approved by the US Food and Drug Administration for the treatment of SARC to grass pollen in the United States on April 1, 2014. OBJECTIVE: To assess the efficacy and safety of the grass pollen sublingual tablets licensed as drugs in the treatment of patients with SARC to grass pollen. DATA SOURCES: Computerized bibliographic searches of MEDLINE, EMBASE, the Cochrane Library, and ClinicalTrials.gov (from inception to April 30, 2014) were supplemented with a manual search of reference lists. STUDY SELECTION: Randomized clinical trials were included if they compared the grass pollen SLIT tablets approved by regulatory authorities in the European Union and the United States for SARC with placebo. DATA EXTRACTION AND SYNTHESIS: Data on populations, interventions, and outcomes were extracted from each RCT according to the intent-to-treat method by 2 independent observers and were combined using the method by DerSimonian and Laird. MAIN OUTCOMES AND MEASURES: The primary end point was the difference in the symptom score and medication score between SLIT and placebo. We pooled data using random-effects meta-analysis, with standardized mean differences (SMDs) and 95% CIs reported. RESULTS: Data were available in 13 RCTs for the symptom score (4659 patients) and in 12 RCTs for the medication score (4558 patients). We found a small treatment benefit in the symptom score (SMD, -0.28; 95% CI, -0.37 to -0.19; P < .001) and in the medication score (SMD, -0.24; 95% CI, -0.31 to -0.17; P < .001). Adverse events were reported in 1384 of 2259 patients (61.3%) receiving SLIT and in 477 of 2279 patients (20.9%) receiving placebo. Seven patients in the SLIT group reported treatment-related adverse events requiring epinephrine. CONCLUSIONS AND RELEVANCE: Findings show a small benefit of the grass pollen sublingual tablets in reducing symptoms and in decreasing the use of symptomatic medication (antihistamines and corticosteroids) in patients with SARC. Considering the low magnitude of the benefit, the convenience and easy administration do not seem to be sufficient reasons for the choice of SLIT.

Analysis of a database to predict the result of allergy testing in vivo in patients with chronic nasal symptoms.

BACKGROUND: This article uses the logistic regression model for diagnostic decision making in patients with chronic nasal symptoms. We studied the ability of the logistic regression model, obtained by the evaluation of a database, to detect patients with positive allergy skin-prick test (SPT) and patients with negative SPT. The model developed was validated using the data set obtained from another medical institution. METHODS: The analysis was performed using a database obtained from a questionnaire administered to the patients with nasal symptoms containing personal data, clinical data, and results of allergy testing (SPT). All variables found to be significantly different between patients with positive and negative SPT (p < 0.05) were selected for the logistic regression models and were analyzed with backward stepwise logistic regression, evaluated with area under the curve of the receiver operating characteristic curve. A second set of patients from another institution was used to prove the model. RESULTS: The accuracy of the model in identifying, over the second set, both patients whose SPT will be positive and negative was high. The model detected 96% of patients with nasal symptoms and positive SPT and classified 94% of those with negative SPT. CONCLUSION: This study is preliminary to the creation of a software that could help the primary care doctors in a diagnostic decision making process (need of allergy testing) in patients complaining of chronic nasal symptoms.

Assessment of a qualitative serological assay to screen for allergic sensitization in elderly subjects.

We used a commercially available specific IgE qualitative serological assay to screen for allergic sensitization. Two hundred twenty-eight elderly subjects took part in the study. Skin-prick tests (SPTs) to a panel of relevant aeroallergens present in the study area were used as the diagnostic reference procedure (gold standard). Subjects with at least one positive SPT (≥3 mml n = 76) were considered to have developed an allergic sensitization. The qualitative assay correctly classified subjects as sensitized to an allergen or not sensitized in 257 of 288 cases (accuracy, 88.9%; 95% CI, 85.0-92.0%). The qualitative assay sensitivity was 70.0 (95% CI, 58.1-79.7) and specificity was 95.7 (95% CI, 92.1-98.0), positive predictive value (PPV) was 85.4 (95% CI, 85.1-93.4), negative predictive value (NPV) was 89.8 (95% CI, 85.1-93.4), positive likelihood ratio (LR(+)) was 16.5 (95% CI, 8.7-31.6), negative LR (LR(-)) was 0.31 (95% CI, 0.21-0.43), and the diagnostic odds ratio (DOR) was 52.2 (95% CI, 21.5-133.6). In the elderly subjects with respiratory symptoms, the qualitative assay correctly classified subjects as allergen sensitized or nonsensitized in 81 of 89 cases (accuracy, 91.0; 95% CI, 85.0-96.9). In this subgroup, the qualitative assay sensitivity was 94.6 (95% CI, 85.1-98.8), specificity was 84.8 (95% CI, 68.1-94.9), PPV was 91.3 (95% CI, 81.0-97.1), and NPV was 90.3 (95% CI, 74.2-97.9). LR(+) was 6.2 (95% CI, 3.0-14.2), LR(-) was 0.06 (95% CI, 0.02-0.17), and the DOR was 98.9 (95% CI, 18.0-621.4). The qualitative serological assay is a valuable tool for the diagnosis of allergic sensitization in a population of elderly subjects.

Chronic spontaneous urticaria: an autoimmune disease? A revision of the literature.

The cause of chronic spontaneous urticaria has been an enigma for decades, but the recognition of functional autoantibodies in some patients with the spontaneous chronic urticaria has opened up a new concept of autoimmune urticaria. Clinical and laboratory features are in keeping with an autoimmune aetiology for many patients with otherwise inexplicable disease, but there is still debate about the importance of functional autoantibodies in the disease pathogenesis, how to test them and the clinical implications for treatment and prognosis. This review will look at the evidence for there being an autoimmune subset of urticaria, the strengths and weaknesses of the available tests in current use.

Clinical course of rhinitis and changes in vivo and in vitro of allergic parameters in elderly patients: a long-term follow-up study.

Changes in rhinitis symptom severity tend to decrease with aging, but whether the decrease is associated with allergic skin test reactivity, serum total and specific IgE, and nasal eosinophils or determined only by aging is poorly understood. The aim of the study was to analyze sensitivity in vivo and in vitro some 15 years after primary testing, skin prick test (SPT), serum total and specific IgE, ratio sIgE/tIgE, and nasal eosinophils in order to evaluate changes due to age and changes due to the severity of rhinitis symptoms. One hundred and eight rhinitis patients who had been investigated in 1995 were re-interviewed and their current allergy re-assessed after a follow-up of 15 years. All patients were SPT with eight common allergens in the area of Palermo (Italy). Rhinitis symptoms tended, on average, to have become milder at the follow-up. All parameters examined showed a decreasing trend in older age groups over the period between the two investigations. Rhinitis symptoms tend to become milder and the allergic parameters both in vivo and in vitro usually decrease in the long run; however, the changes in rhinitis symptoms appear to be related to changes in the nasal eosinophils, independently of SPT and serum-specific IgE.

Efficacy of subcutaneous and sublingual immunotherapy with grass allergens for seasonal allergic rhinitis: a meta-analysis-based comparison.

BACKGROUND: Subcutaneous (SCIT) and sublingual (SLIT) immunotherapy are the 2 most prescribed routes for administering allergen-specific immunotherapy. They were shown to be effective in control of symptoms and in reducing rescue medication use in patients with allergic diseases, but their effectiveness has to be balanced against side effects. In recent years, SLIT has been increasingly prescribed, instead of SCIT, because of improved safety and easy administration. OBJECTIVE: We assessed which route is the most effective in the treatment of patients with seasonal allergic rhinitis to grass pollen. METHODS: An indirect meta-analysis-based comparison between SCIT and SLIT was performed. Treatment efficacy was determined as the standardized mean difference (SMD) in symptom and medication scores obtained with active treatment, SCIT or SLIT, compared with placebo. Studies were included if they were double-blind randomized controlled trials comparing SCIT or SLIT with placebo. Thirty-six randomized controlled trials (3014 patients; 2768 controls) were analyzed. RESULTS: The overall effect size of SCIT for symptom score (SMD, -0.92; 95%CI, -1.26 to -0.58) was significantly higher than SLIT, both administered via drops (SMD, -0.25; 95% CI, -0.45 to -0.05) and tablets (SMD, -0.40; 95%CI, -0.54 to -0.27). Similar results were reported for medication score (SCIT: SMD, -0.58; 95% CI, -0.86 to -0.30. SLIT drops: SMD, -0.37; 95% CI, -0.74 to -0.00. SLIT tablets SMD, -0.30; 95% CI, -0.44 to -0.16). CONCLUSIONS: Our results provide indirect but solid evidence that SCIT is more effective than SLIT in controlling symptoms and in reducing the use of antiallergic medications in seasonal allergic rhinoconjuntivitis to grass pollen.

Differences and similarities between allergic and nonallergic rhinitis in a large sample of adult patients with rhinitis symptoms.

BACKGROUND: Allergic rhinitis (AR) and nonallergic rhinitis (NAR) may present with different clinical and laboratory characteristics. METHODS: A total of 1,511 consecutive patients, aged 18-81 years, diagnosed with rhinitis, 56% females and 44% males, underwent complete allergic evaluation including skin prick test, blood eosinophil counts, nasal eosinophil counts, peak nasal inspiratory flow (PNIF) measurement and evaluation of nasal symptoms using a visual analog scale (VAS). RESULTS: A total of 1,107 patients (73%)had AR, whereas 404 (27%) had NAR. Patients with NAR were older and predominantly female. A higher nasal eosinophils count was associated with AR and a lack of clinical response to antihistamines. AR patients had more sneezing and nasal pruritus, whereas NAR was characterized mainly by nasal obstruction and rhinorrhea. AR patients had more severe symptoms and recurrent conjunctivitis, whereas NAR patients had slightly more frequent episodes of recurring headaches as well as olfactory dysfunction. PNIF, blood eosinophil counts and VAS of nasal symptoms were higher in patients with AR. In a final logistic regression model, 10 variables were statistically different between AR and NAR: age [OR 0.97 (95% CI 0.96-0.98)], sneezing [OR 4.09 (95% CI 2.78-6.00)], nasal pruritus [OR 3.84 (95% CI 2.60-5.67)], mild symptoms [OR 0.21 (95% CI 0.09-0.49)], intermittent/severe nasal symptoms [OR 3.66 (95% CI 2.06-6.50)], VAS [OR 1.06 (95% CI 1.04-1.08)], clinical response to antihistamines [OR 22.59 (95% CI 13.79-37.00)], conjunctivitis [OR 4.49 (95% CI 2.86-7.05)], PNIF [OR 1.01 (95% CI 1.00-1.01)] and nasal eosinophil counts [OR 1.14 (95% CI 1.10-1.18)]. Receiver operating characteristic analysis showed high predictive accuracy for a model including these variables independently of the diagnosis of AR/NAR (cutoff <0.74). CONCLUSIONS: We showed that the several clinical and laboratory parameters reported above may help to reinforce or exclude the diagnosis of AR obtained with skin prick test.

Polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein are associated with chronic spontaneous urticaria and urinary leukotriene E4.

The mechanisms of chronic spontaneous urticaria (CSU) continue to be unknown. Our working hypothesis is that polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein may be involved in the pathways leading to CSU. We examined five candidate polymorphisms of cyclo-oxygenases 1 and 2 and of 5-lipo-oxygenase-activating protein in 109 controls and in 94 CSU patients from Northern Italy. We also examined the levels of urinary leukotriene E4 (LTE4) before and after challenge with ASA. A multiple regression model was found to show that COX-2 5'UTR T/G, COX-2 Exon 10 T/C, and FLAP -336 G/A polymorphisms were significantly associated with CSU, with the minor allele more represented in CSU group. Similar results were obtained as regards the specific association with ASA-tolerated CSU and ASA-exacerbated CSU. Evaluating a polygenic model, reflecting the sum of the concomitant alleles associated with CSU (i.e. COX-2 5'UTR G allele, COX-2 Exon 10 C allele, and FLAP -336 G/A allele), the proportion of CSU patients increased progressively with the increasing number of unfavourable alleles. Finally, in a linear regression model after adjustment for disease status COX-1 22 T carriership remained a significant predictor of post-challenge high urinary LTE4 levels. Our results support the hypothesis that polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein may be associated with CSU.

Efficacy of sublingual immunotherapy with grass allergens for seasonal allergic rhinitis: a systematic review and meta-analysis.

BACKGROUND: The benefit of sublingual immunotherapy (SLIT) with grass allergens for seasonal allergic rhinitis has been extensively studied, but data on efficacy are still equivocal. OBJECTIVE: To assess the effectiveness of SLIT with grass allergens in the reduction of symptoms and medication in patients with seasonal allergic rhinitis to grass pollen. METHODS: Computerized bibliographic searches of MEDLINE (1995-2010) were supplemented by hand searches of reference lists. Studies were included if they were double-blind randomized controlled trials (RCTs) comparing SLIT to placebo and if they included patients with history of allergy to grass pollen treated with natural grass pollen extracts. Nineteen RCTs with 2971 patients were analyzed. The outcomes assessed were symptom and medication scores. RESULTS: Using a random-effects model, SLIT with grass allergens significantly reduces both symptoms (standardized mean difference, -0.32; 95% CI, -0.44 to -0.21) and medication use (standardized mean difference, -0.33; 95% CI, -0.50 to -0.16) compared with placebo. The treatment is more efficacious in adults than in children. Prolonging duration of preseasonal treatment for more than 12 weeks improves the treatment efficacy. CONCLUSION: This meta-analysis found that SLIT with grass allergens is effective in patients with seasonal allergic rhinitis compared with placebo. The benefit is clinically modest, and criteria are needed to identify patients most likely to benefit from SLIT.

The predictive role of atherogenic dyslipidemia in subjects with non-coronary atherosclerosis.

BACKGROUND: Recent findings have suggested that subjects with non-coronary atherosclerosis may show elevated prevalence of atherogenic dyslipidemia, including higher triglyceride levels, reduced HDL-cholesterol concentrations and increased levels of small, dense low-density lipoproteins (LDL). These three lipid abnormalities constitute the so-called "atherogenic-lipoprotein-phenotype" (ALP) but its predictive role in these patients still remains to be established. METHODS: We performed a 2-year follow-up study to assess clinical and biochemical predictors of cardiovascular events in 44 male patients (64+/-5 years, BMI: 27+/-3), 26 with peripheral arterial disease and 18 with abdominal aortic aneurysm. Beyond traditional cardiovascular risk factors, we measured LDL size and subclasses by gradient gel electrophoresis. RESULTS: Clinical events were registered in the 43% of patients. At univariate analysis we found that patients with events had increased prevalence of hypertension (p=.0098), diabetes (p=.0089), family history of cardiovascular diseases (p=.0089), of elevated small, dense LDL (p=.0222) and ALP (p=.0224). At multivariate analysis (including all clinical and laboratory variables) we found the following independent predictors of events: hypertension (OR 8.9, p=.0347), diabetes (OR 9.4, p=.0270), elevated small, dense LDL (OR 6.9, p=.0488) and ALP (OR 8.7, p=.0497). CONCLUSIONS: This is the first study that evaluated the predictive role of ALP beyond traditional cardiovascular risk factors in patients with peripheral arterial disease or abdominal aortic aneurysm. We confirmed that hypertension and diabetes are strong predictors of cardiovascular events in these subjects but ALP seems to be an independent predictor too. Yet, the therapeutical consequences of these findings need to be tested by future studies.