Nutrigenetic response to omega-3 fatty acids in obese asthmatics (NOOA): rationale and methods

Importance of diet in children and adolescents with obesity and asthma

Both obesity and asthma are increasingly being diagnosed in the childhood population. Obesity is linked to a greater asthma morbidity, and it increases the risk of severity of the disease course. The association between these 2 disorders has not yet been fully elucidated; however, several putative factors have been proposed related to mechanical and inflammatory aspects of obesity. Diet is an important adjustable element in obesity and asthma management. An unhealthy diet based on processed food is likely to promote chronic inflammation in both conditions; hence, appropriate nutrition should be an integral part of the children's therapy. This review discusses dietary models that have a positive impact on patient health.

Breast feeding, obesity, and asthma association: clinical and molecular views

Asthma is a chronic condition that affects children worldwide. Accumulating number of studies reported that the prevalence of pediatric obesity and asthma might be altered through breastfeeding. It has been proposed that Leptin, which exists in human milk, is oppositely associated with weight increase in newborns. It may also influence peripheral immune system by promoting TH1 responses and suppressing TH2 cytokines. Leptin influences body weight and immune responses through complex signaling pathways at molecular level. Although previous studies provide explanations for the protective role of breastfeeding against both obesity and asthma, other factors such as duration of breastfeeding, parental, and prenatal factors may confound this relationship which requires further research.

An Overview of the Obese-Asthma Phenotype in Children

Asthma is the most common chronic disease in childhood. Overweight and obesity are included among the comorbidities considered in patients with difficult-to-treat asthma, suggesting a specific phenotype of the disease. Therefore, the constant increase in obesity prevalence in children and adolescents raises concerns about the parallel increase of obesity-associated asthma. The possible correlation between obesity and asthma has been investigated over the last decade by different authors, who suggest a complex multifactorial relationship. Although the particular non-eosinophilic endotype of obesity-related asthma supports the concept that high body weight precedes asthma development, there is ongoing debate about the direct causality of these two entities. A number of mechanisms may be involved in asthma in combination with obesity disease in children, including reduced physical activity, abnormal ventilation, chronic systemic inflammation, hormonal influences, genetics and additional comorbidities, such as gastroesophageal reflux and dysfunctional breathing. The identification of the obesity-related asthma phenotype is crucial to initiate specific therapeutic management. Besides the cornerstones of asthma treatment, lifestyle should be optimized, with interventions aiming to promote physical exercise, healthy diet, and comorbidities. Future studies should clarify the exact association between asthma and obesity and the mechanisms underlying the pathogenesis of these two related conditions with the aim to define personalized therapeutic strategies for asthma management in this population.

Fish Oil Supplementation in Overweight/Obese Patients with Uncontrolled Asthma. A Randomized Trial

Rationale: Omega-3 fatty acid (n3PUFA) supplementation has been proposed as a promising antiasthma strategy. The rs59439148 ALOX5 polymorphism affects leukotriene production and possibly inflammatory responses to n3PUFA. Objectives: Assess the effects of n3PUFA supplementation and ALOX5 genotype on asthma control in patients with obesity and uncontrolled asthma. Methods: This multicenter trial among 12- to 25-year-olds with overweight/obesity and uncontrolled asthma randomized subjects in a 3:1 allotment to n3PUFA (4 g/d) or soy oil control for 24 weeks. Asthma Control Questionnaire was the primary outcome; secondary outcomes included blood leukocyte n3PUFA levels, urinary leukotriene-E4, spirometry, and asthma-related events. The number of SP1 tandem repeats in rs59439148 determined ALOX5 genotype status. Simple and multivariable generalized linear models assessed effects on outcomes. Results: Ninety-eight participants were randomized (77 to PUFA, 21 to control), and more than 86% completed all visits. Asthma and demographic characteristics were similar among treatment groups. n3PUFA treatment increased the n3-to-n6 PUFA ratio in circulating granulocytes (P = 0.029) and monocytes (P = 0.004) but did not affect mean Asthma Control Questionnaire change at 6 months (n3PUFA: mean, -0.09; 95% confidence interval [CI], 0.09 to 0.10; vs. control: mean, -0.18; 95% CI, -0.42 to 0.06; P = 0.58). Changes in urinary leukotriene-E4 (P = 0.24), forced expiratory volume in 1 second % predicted (P = 0.88), and exacerbations (relative risk [RR], 0.92; 95% CI, 0.30-2.89) at 6 months were similar in both groups. n3PUFA treatment was associated with reduced asthma-related phone contacts (RR, 0.34; 95% CI, 0.13-0.86; P = 0.02). ALOX5 genotype did not affect n3PUFA treatment responses. Conclusions: We did not find evidence that n3PUFA use improves most asthma-related outcomes and cannot recommend it as a prevention strategy for overweight/obese patients with asthma. Clinical trial registered with www.clinicaltrials.gov (NCT01027143).

Lipid mediators and asthma: Scope of therapeutics

Lipids and their mediators are known to play a pro-inflammatory role in several human diseases including asthma. The influence of leukotrienes and prostaglandins through arachidonate metabolism in asthma pathophysiology is well established and hence, prompted the way for therapeutic strategies targeting lipid metabolites. In addition, various types of fatty acids have been reported to play a diverse role in asthma. For instance, CD4⁺ T-lymphocytes differentiation towards T-effector (T_eff) or T-regulatory (Tregs) cells seems to be controlled reciprocally by fatty acid metabolic pathways. Further, the dysregulated lipid status in obesity complicates the asthma manifestations suggesting the role of lipid metabolites particularly ω-6 fatty acids in the process. On the other hand, clinical and pre-clinical studies suggests the role of short chain fatty acids in curbing asthma through upregulation of T-regulatory cells or clearance of inflammatory cells through promoting apoptosis. Accordingly, the present review compiles various studies for comprehensive analysis of different types of lipid based metabolites in asthma manifestation. Finally, we have proposed certain strategies which may enhance the usefulness of lipid mediators for balanced immune response during asthma.

Children with Obesity and Asthma: Which Are the Best Options for Their Management?

Obesity and asthma are complex disorders related to gene-environment interactions and various lifestyle factors. At present, they represent two of the most significant paediatric health problems worldwide, particularly in industrialized nations. The aim of this narrative review is to evaluate possible therapeutic strategies to manage asthma in children with overweight/obesity. PubMed was used to search for all of the studies published from January 2008 to June 2018 using the following key words: “asthma” and “overweight” or “obesity” or “obese” and “children” or “paediatric”. The literature review showed that growing evidence underlines the existence of an “obese asthma” phenotype characterised by difficult-to-control asthma with additional symptoms, worse control, more frequent and severe exacerbations, reduced response to inhaled corticosteroids, and lower quality of life than other phenotypes. Currently, therapeutic strategies centred on prevention are suggested and the development of resources to assist families with weight loss strategies seems useful for effective weight control and optimal asthma management. Studies on vitamin D supplementation and further knowledge are needed to better define the best therapeutic options to manage asthma in children with overweight/obesity and to reduce the onset and severity of this chronic respiratory disease through the design of a multifactorial intervention.

A novel nutritional intervention improves lung function in overweight/obese adolescents with poorly controlled asthma: the Supplemental Nutrition in Asthma Control (SNAC) pilot study

Asthma in the obese is often severe, difficult to treat, and characterized by less eosinophilic inflammation than asthma in the nonobese. Obesity-associated metabolic dysregulation may be a causal factor. We previously reported that a nutrient- and fiber-dense bar [Children's Hospital Oakland Research Institute (CHORI)-bar], which was designed to fill gaps in poor diets, improved metabolism in healthy overweight/obese (OW/OB) adults. In this pilot trial, OW/OB adolescents with poorly controlled asthma were randomized to weekly nutrition/exercise classes with or without twice-daily CHORI-bar consumption. Intent-to-treat analysis did not indicate CHORI-bar-specific effects. However, restricting the analysis to participants with acceptable compliance and a relatively low fraction of exhaled nitric oxide (FENO; <50/ ppb, a surrogate for noneosinophilic asthma; study participants: CHORI-bar, n = 16; controls, n = 15) indicated that CHORI-bar-specific, significant improvements in lung function (forced vital capacity, percent-predicted forced expiratory volume in 1 s, and percent-predicted forced expiratory flow between 25 and 75% of forced vital capacity), primarily in participants with low chronic inflammation (high-sensitivity C-reactive protein <1.5 mg/L). (We previously observed that chronic inflammation blunted CHORI-bar-induced metabolic improvements in healthy OW/OB adults.) Lung function improvement occurred without weight loss and was independent of improvements in metabolic and anthropometric end points and questionnaire-based measures of asthma control and quality of life. This study suggests that a nutritional intervention can improve lung function in OW/OB adolescents with asthma and relatively low FENO without requiring major changes in dietary habits, lifestyle, or weight loss and that this effect is blunted by chronic inflammation.-Bseikri, M., McCann, J. C., Lal, A., Fong, E., Graves, K., Goldrich, A., Block, D., Gildengoren, G. L., Mietus-Snyder, M., Shigenaga, M., Suh, J., Hardy, K., Ames, B. N. A novel nutritional intervention improves lung function in overweight/obese adolescents with poorly controlled asthma: the Supplemental Nutrition in Asthma Control (SNAC) pilot study.

Nutrigenomic Information in the openEHR Data Set

BACKGROUND

The traditional concept of personalized nutrition is based on adapting diets according to individual needs and preferences. Discussions about personalized nutrition have been on since the Human Genome Project, which has sequenced the human genome. Thenceforth, topics such as nutrigenomics have been assessed to help in better understanding the genetic variation influence on the dietary response and association between nutrients and gene expression. Hence, some challenges impaired the understanding about the nowadays important clinical data and about clinical data assumed to be important in the future.

OBJECTIVE

Finding the main clinical statements in the personalized nutrition field (nutrigenomics) to create the future-proof health information system to the openEHR server based on archetypes, as well as a specific nutrigenomic template.

METHODS

A systematic literature search was conducted in electronic databases such as PubMed. The aim of this systemic review was to list the chief clinical statements and create archetype and templates for openEHR modeling tools, namely, Ocean Archetype Editor and Ocean Template Design.

RESULTS

The literature search led to 51 articles; however, just 26 articles were analyzed after all the herein adopted inclusion criteria were assessed. Of these total, 117 clinical statements were identified, as well as 27 archetype-friendly concepts. Our group modeled four new archetypes (waist-to-height ratio, genetic test results, genetic summary, and diet plan) and finally created the specific nutrigenomic template for nutrition care.

CONCLUSION

The archetypes and the specific openEHR template developed in this study gave dieticians and other health professionals an important tool to their nutrigenomic clinical practices, besides a set of nutrigenomic data to clinical research.

Pediatric Obesity-Related Asthma: The Role of Metabolic Dysregulation

The burden of obesity-related asthma among children, particularly among ethnic minorities, necessitates an improved understanding of the underlying disease mechanisms. Although obesity is an independent risk factor for asthma, not all obese children develop asthma. Several recent studies have elucidated mechanisms, including the role of diet, sedentary lifestyle, mechanical fat load, and adiposity-mediated inflammation that may underlie the obese asthma pathophysiology. Here, we review these recent studies and emerging scientific evidence that suggest metabolic dysregulation may play a role in pediatric obesity-related asthma. We also review the genetic and epigenetic factors that may underlie susceptibility to metabolic dysregulation and associated pulmonary morbidity among children. Lastly, we identify knowledge gaps that need further exploration to better define pathways that will allow development of primary preventive strategies for obesity-related asthma in children.

Omega-3 Fatty Acids Supplementation in Children to Prevent Asthma: Is It Worthy?-A Systematic Review and Meta-Analysis

Asthma is one of the most common respiratory diseases affecting all age groups. The world is now trying to identify some dietary factors which can play a preventive role. We performed this systematic review and meta-analysis of RCTs to assess the effect of intake of polyunsaturated fatty acid (PUFA) in infancy and/or childhood on incidence of asthma or wheezing episodes. We searched MEDLINE, EBSCO, Trip, and Google Scholar up to January 31, 2015. All RCTs where infants or children who were given omega-3 fatty acid supplementation and which reported incidence of asthma and/or wheezing episodes as dichotomous outcomes were included in this review. Random effects model was used for pooling the risk estimates. Total five articles were included. Most of them were from Australia. On meta-analysis, the pooled estimate of odds ratios by random effects model showed no significant change in incidence of asthma after supplementation of omega-3 FA in infancy or childhood (OR 0.974; CI 0.646, 1.469; p = 0.900). We concluded that a multicentric RCT is required to assess the effect of omega-3 FA supplementation exclusively to infants or children to predict the best time of omega-3 FA supplementation to prevent asthmatic or wheezing episodes later in life.

The Asthma Control Questionnaire as a clinical trial endpoint: past experience and recommendations for future use

The goal of asthma treatment is to control the disease according to guidelines issued by bodies such as the Global Initiative for Asthma. Effective control is dependent upon evaluation of symptoms, initiation of appropriate treatment and minimization of the progressive adverse effects of the disease and its therapies. Although individual outcome measures have been shown to correlate with asthma control, composite endpoints are preferred to enable more accurate and robust monitoring of the health of the individual patient. A number of validated instruments are utilized to capture these component endpoints; however, there is no consensus on the optimal instrument for use in clinical trials. The Asthma Control Questionnaire (ACQ) has been shown to be a valid, reliable instrument that allows accurate and reproducible assessment of asthma control that compares favourably with other commonly used instruments. This analysis provides a summary of the use of ACQ in phase II, III and IV asthma trials. Comparisons between the ACQ and other instruments are also presented. Our analysis suggests that the ACQ is a valid and robust measure for use as a primary or secondary endpoint in future clinical trials.

Obesity and asthma in children: current and future therapeutic options

With the childhood prevalence of obesity and asthma increasing, it is important for pediatric professionals to appreciate that obesity modifies the diagnosis and management of asthma. These disease modifications present challenges to clinical management, including decreased responsiveness to controller therapy and decreased quality of life compared with normal-weight asthmatic children. While consensus guidelines do not currently suggest specific changes in asthma management for obese patients, management of some patients may be improved with consideration of the latest evidence. This article briefly summarizes what is known regarding the complex relationship between obesity and asthma in children, and discusses practical issues associated with the diagnosis and effective clinical management of asthma in obese children. On average, obese patients with asthma do not respond as well to inhaled corticosteroid therapy. Management approaches including weight loss and routine exercise are safe, and may improve important asthma outcomes. Asthma providers should learn to facilitate weight loss for their obese patients. In addition, pharmacologic interventions for weight loss in obese asthma, though not currently recommended, may soon be considered.

Dietary marine fatty acids (fish oil) for asthma

BACKGROUND

Epidemiological studies suggest that a diet high in marine fatty acids (fish oil) may have beneficial effects on inflammatory conditions such as rheumatoid arthritis and possibly asthma.

OBJECTIVES

1. To determine the effect of marine n-3 fatty acid (fish oil) supplementation in asthma. 2. To determine the effect of a diet high in fish oil in asthma.

SEARCH STRATEGY

The Cochrane Airways Review Group register was search using the terms: marine fatty acids OR diet OR nutrition OR fish oil OR eicosapentaenoic acid OR EPA. Bibliographies of retrieved trials were searched and fish oil manufacturers contacted.

SELECTION CRITERIA

Randomised controlled trials in patients with asthma more than two years of age were included. The study duration had to be in excess of 4 weeks. Double blind trials were preferred, but single-blind and open trials were also reviewed for possible inclusion. Three reviewers read each paper, blind to its identity. Decisions concerning inclusion were made by simple majority. Quality assessment was performed by all three reviewers independently.

DATA COLLECTION AND ANALYSIS

The only comparison possible was between marine n-3 fatty acid supplementation and placebo. There were insufficient trials to examine dietary manipulation alone.

MAIN RESULTS

Eight randomised controlled trials conducted between 1986 and 1998 satisfied the inclusion criteria. Six were of parallel design and two were cross-over studies. Seven compared fish oil with placebo whilst one compared high dose vs low dose marine n-3 fatty acid supplementation. None of the included studies reported asthma exacerbations, health status or hospital admissions. There was no consistent effect on any of the analyzable outcomes: FEV1, peak flow rate, asthma symptoms, asthma medication use or bronchial hyper reactivity. The single study performed in children also combined dietary manipulation with fish oil supplementation and showed improved peak flow and reduced asthma medication use. There were no adverse events associated with fish oil supplements. Updated Search conducted August 2000. No new trials were found.

REVIEWER'S CONCLUSIONS

There is little evidence to recommend that people with asthma supplement or modify their dietary intake of marine n-3 fatty acids (fish oil) in order to improve their asthma control. Equally, there is no evidence that they are at risk if they do so.