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International Updates

Asthma / Lung Function / Respiratory Function / Allergies

Issue 93

SPECTOR and SURETTE, University of California-Los Angeles, Los Angeles, California, USA, calallergy@dnamail.com, have reviewed the role of dietary fat in the management of asthma.
Background: The role of diet in the management of asthma is reviewed. Evolution of Western diet has contributed to the prevalence of asthma, and dietary modification may reduce the symptoms of asthma.
Methods: The literature was searched for any relevant articles published in English.
Results: The prevalence of both asthma and obesity which often occur together has increased drastically in recent years. Studies suggest that increased intake of specific nutrients can cause changes in the frequency and severity of asthma. It has also been suggested that the increase in asthma is due to increased exposure to diesel fumes or lack of exposure to infectious agents in childhood, thus generating an immune system biased towards a Th2 response and increased cytokine and leukotriene production. It has been observed that these high levels of inflammatory mediators can be countered by dietary administration of oils containing gamma-linolenic acid and eicosapentaenoic acid.
Conclusion: There is evidence that obesity and dietary patterns, especially the intake of dietary fatty acids, contribute to symptoms of asthma. Dietary modification may help patients manage their asthma as well as contribute to their overall health.
Spector SL, Surette ME. Diet and asthma: has the role of dietary lipids been overlooked in the management of asthma? Annals of Allergy, Asthma and Immunology 90 (4): 371-378, Apr 2003.

Issue 92

MIHRSHAHI and colleagues, Clinical Epidemiology Unit, The Children’s Hospital, Westmead, NSW, Australia, report on the eighteen months outcomes of house dust mite avoidance and dietary fatty acid modification in childhood asthma prevention.
Background: The hypothesis driving this study was that avoidance of house dust mites or supplementation with n-3 fatty acids or both together could reduce the incidence of asthma and allergy in children, as suggested by observational evidence.
Methods: In this randomized controlled trial, 616 pregnant women were randomized to either house dust mite avoidance (i.e. the use of impermeable mattress covers and an agaricide) or control, and use of an oil supplement high in n-3 fatty acids or control. Allergy was assessed by skin prick testing. Symptoms, diagnoses, and medication histories were obtained in parental interviews.
Results: The diet resulted in a nearly 10% reduction of wheezing (p = 0.02) but had no effect on serum IgE (an indicator for allergic reactions), atopy, or doctor’s diagnosis of asthma. The house dust mites avoidance was associated with a lower use of oral steroids but did not otherwise affect the outcomes.
Conclusions: Increasing dietary n-3 fatty acids may have a beneficial effect on the prevalence of wheezing in the first 18 months of life. Follow-up to 5 years is under way.
Mihrshahi S, Peat JK, Marks GB, Mellis CM, Tovey ER, Webb K, Britton WJ, Leeder SR. Eighteen-month outcomes of house dust mite avoidance and dietary fatty acid modification in the Childhood Asthma Prevention Study (CAPS). The Journal of Allergy and Clinical Immunology 111 (1): 162-168, Jan 2003.

Comment: Due to the restrictions placed on researchers, it is regrettable that a more wholistic research study couldn’t have been conducted, investigating more than simply 2 approaches – dust mite avoidance and n-3 supplements. I, for one, would applaud a comprehensive study applying homeopathy, breathing/yoga techniques, diet and nutritional supplements based on non-IgE allergic testing, etc.

Issue 91

OMENAAS and colleagues, Department of Thoracic Medicine, University of Bergen, Norway, ernst.omenaa@haukeland.no, have found that dietary vitamin C intake is inversely related to coughing and wheezing in young smokers.
Background: The study aimed to investigate whether dietary intake of vitamin C, an important antioxidant, could ameliorate self-reported respiratory symptoms on young adults.
Methods: A random sample of 4300 subjects living in Bergen aged between 20 and 44 years received a postal questionnaire on respiratory symptoms. 80% responded. Vitamin C intake was estimated from a food-frequency questionnaire.
Results: Significant differences in vitamin C intake were found with current smokers having the lowest intake. Dietary vitamin C intake was inversely related to coughing and wheezing. In smokers, the odds ratios for ‘morning cough’, ‘chronic cough’, and ‘wheeze’ were 0.68, 0.69, and 0.75 in the highest compared to the lowest tertile of vitamin C intake.
Conclusions: Among young Norwegian adults who have a low prevalence of asthma and high prevalence of smoking-related respiratory symptoms, dietary vitamin C intake may act as an antioxidant and reduce coughing and wheezing in smokers.
Omenaas E, Fluge O, Buidt AS, Vollmer WM, Gulsvik A. Dietary vitamin C intake is inversely related to cough and wheeze in young smokers. Respiratory Medicine 97 (2): 134-142, Feb 2003.
Comment: Next time someone you know tells you that Vitamin C is useless and a waste of money, try to quote them this study.

RAM and co-workers, Department of Physiological Medicine, St George’s Hospital Medical School, University of London, Tooting, UK, fram@sghms.ac.uk, have reviewed (30 references) breathing re-training for asthma.
Abstract: A systematic review of the literature was undertaken in order to determine the effectiveness of breathing re-training in the management of asthma. Six randomized controlled trials were identified, but due to variation in trial outcomes, limited reporting of study data, and the small number of included trials it was not possible to draw any definitive conclusions. However individual trials report benefit from breathing re-training. It is therefore recommended that large-scale trials using breathing re-training are conducted in order to clarify this important question.
Ram FSF, Holloway EA, Jones PW. Breathing retraining for asthma. Respiratory Medicine 97 (5): 501-507, May 2003.

Issue 90

OMLAND and colleagues, Department of Environmental and Occupational Medicine, University of Aarhus, University Park Building. 260, Vennelyst Boulevard 6, DK 8000 Aarhus C, OM@aas.nja.dk, have found that selenium in serum and urine is associated with mild asthma and atopy.
Background: The aim of the study – the SUS study – was to examine relationships between selenium status, asthma, bronchial hyperresponsiveness (BHR) and atopy.
Methods: 72 men with mild asthma, 41 men with BHR, and 41 men with no respiratory symptoms, all aged between 17 and 22 years, were examined. All underwent a medical interview, and FEV1 and FVC were recorded. Histamine bronchial reactivity was measured, skin prick test to assess inhalant allergy was performed, and selenium was measured in serum and urine.
Results: Selenium in serum was lower in subjects with asthma, and selenium in urine was lower in subjects with asthma or atopy compared to those with no respiratory symptoms (p = 0.05). In men with asthma atopy was significantly associated with selenium in urine (p = 0.05). Subjects with BHR had the same selenium status as subjects with no respiratory symptoms. Also, smokers had lower selenium concentrations in serum.
Conclusions: Selenium status was associated to asthma and smoking. Measuring selenium in urine might add further information to possible relations between selenium, asthma, and atopy.
Omland O, Deguchi Y, Sigsgaard T, Hansen JC. Selenium serum and urine is associated to mild asthma and atopy. The SUS study. Journal of Trace Elements in Medicine and Biology 16 (2): 123-127, 2002.

MEDICI and co-workers, Department of Internal Medicine, University Hospital Zurich, Switzerland, media@bluewin.ch, have conducted a long-term randomized study of real versus sham acupuncture in patients with bronchial asthma.
Background: Acupuncture is traditionally used in China for the treatment of asthma. There is still a dearth of high quality studies showing its effectiveness or otherwise.
Methods: In this randomized partially blinded study, 66 patients with mild to moderate chronic asthma were divided into three groups: real acupuncture (23 patients), sham acupuncture (23 patients), and no treatment (20 patients). After 2 weeks of run-in, two acupuncture periods of 4 weeks each were followed by a 6 months observation period. The primary outcome measure was peak expiratory flow (PEF). Secondary outcomes were forced expiratory volume in one second (FEV1), airway responsiveness, symptoms of asthma, use of drugs, and wellbeing of patients. In addition the effect of the treatment on eosinophils and eosinophil cationic protein in blood and sputum was assessed.
Results: PEF variability decreased in all groups. In a subgroup of patients, PEF variability decreased significantly compared to controls with both real and sham needling. Most of the other variables did not differ from those obtained in controls. Eosinophils decreased in all groups, and there was possibly a small effect of real compared to sham acupuncture on eosinophilic inflammation at 10 months.
Conclusions: Any effects seen in this study were small and possibly clinically not relevant. These data do not support the use of acupuncture for the treatment of chronic asthma.
Medici TC, Grebski E, Wu J, Hinz G, Wuethrich B. Acupuncture and bronchial asthma: a long-term randomized study of the effects of real versus sham acupuncture compared to controls in patients with bronchial asthma. The Journal of Alternative and Complementary Medicine 8 (6): 737-750, Dec 2002.

Comment: As with most research, the devil is in the detail. In this instance, there were decreases in peak expiratory flow (PEF) variability in all groups, including a significant PEF decrease in a subgroup of patients in both the real and sham acupuncture groups compared with the controls. Hence, there was a therapeutic effect from acupuncture in some patients. Due to relatively small numbers and probably diverse clinical parameters of patients, definitive interpretation is difficult, and hence further research is needed before pronouncing that acupuncture is not useful in the treatment of chronic asthma.

Issue 89

HONDRAS and colleagues, Consortial Center for Chiropractic, 30W009 Willow Court, Warrenville, Illinois 60555-1018, USA, mhondras@interaccess.com, reviewed (73 references) manual therapies for asthma.
Background: A variety of manual therapies is used to treat patients with asthma. Manual therapy practitioners include physiotherapists, respiratory therapists, chiropractors, and osteopathic physicians. A systematic review was conducted in an effort to evaluate the evidence for the effects of manual therapies in the treatment of bronchial asthma.
Methods: Trials were searched in computerized databases (EMBASE, CINHAL, MEDLINE, Cochrane Complementary Medicine Field, Cochrane Rehabilitation Field, ICL, and MANTIS). In addition, bibliographies from included studies were assessed, and authors contacted for more information about published and unpublished trials. Trials were included if they were randomized, included asthmatic children or adults, examined one or more manual therapies, and included clinical outcomes. All three reviewers independently extracted data and evaluated the quality of studies.
Results: Five randomized controlled trials were selected for the review. Two trials were on chiropractic manipulation, and neither found any differences in outcome between chiropractic spinal manipulation and a sham manoeuvre. The other three trials were small. One found
differences in lung function between massage and a relaxation control group. One compared chest physiotherapy to placebo, and one compared footzone therapy to no treatment. Neither of these found any differences in lung function.
Conclusions: There is insufficient evidence to support the use of manual therapies for patients with asthma. There is a need to conduct adequately sized trials examining the effects of manual therapies on asthma using relevant clinical outcomes.
Hondras MA, Linde K, Jones AP. Manual therapy for asthma. The Cochrane Database of Systematic Reviews 2002 (4): CD001002.

MARTIN and colleagues have reviewed (32 references) and meta-analyzed 11 published randomized controlled trials of acupuncture for asthma.
Background: Results from randomized controlled trials of acupuncture for the treatment of asthma are contradictory in that they suggest both a beneficial and a detrimental effect.
Methods: A formal systematic review and meta-analysis were conducted of all randomized controlled trials in the published literature comparing acupuncture at real and sham points. For inclusion trials had to measure at least one of the following outcomes: peak
expiratory flow rate, forced expiratory volume in one second, and forced vital capacity. Estimates of the standardized mean difference between acupuncture and placebo were computed for each trial and combined to estimate an overall effect.
Results: 11 trials met the inclusion criteria and yielded numerical data. Standardized differences were between 0.071 and 0.133 in favour of real acupuncture, which does not constitute a conventionally significant effect. However the meta-analysis was limited by sample sizes, missing information in individual trials, adjustment of baseline characteristics, and a possible bias against acupuncture in that some sham points used may not be completely inactive.
Conclusions: There is an obvious need to conduct a full-scale randomized controlled trial of acupuncture for asthma, especially addressing the prognostic value of the aetiology of the disease.
Martin J, Donaldson ANA, Villaroel R, Parmar MKB, Ernst E, Higginson IJ. Efficacy of acupuncture in asthma: systematic review and meta-analysis of published data from 11 randomised controlled trials. The European Respiratory Journal 20 (4): 846-852, Oct 2002.

Issue 86

GAZDIK and co-workers, Department of Clinical Immunology, Institute of Preventive and Clinical Medicine, Bratislava, report decreased levels of coenzyme Q10 in patients with bronchial asthma.

Background: It is generally accepted that free radicals play a role in the pathogenesis of bronchial asthma. Thus antioxidant supplementation may be a promising adjuvant therapy. The aim of this study was to assess coenzyme Q10, alpha-tocopherol, beta-carotene, malondialdehyde, and eosinophil cationic protein in the blood of asthmatics.

Methods: 56 patients aged 19 – 72 years suffering from allergic asthma were enrolled, as well as 25 healthy volunteers. Vitamin and enzyme activities were measured in blood samples.

Results: CoQ10 was decreased in asthmatics as compared to healthy controls (p = 0.001). alpha-tocopherol was decreased in asthmatics as well if less drastically. No changes were seen in beta-carotene concentrations. Decreased CoQ10 and alpha-tocopherol were correlated.

Conclusions: The study finds suboptimal concentrations of CoQ10 in asthmatics and suggests a rationale for its supplementation.

Gadzik F, Gvozdjakova A, Nadvornikova R, Repicka L, Jahnova E, Kucharska J, Pijak MR, Gadzikova K, et al. Decreased levels of coenzyme Q(10) in patients with bronchial asthma. Allergy 57 (9): 811-814, Sep 2002.

Comment: Again, an extremely promising clinical result, particularly regarding CoQ10, and, to a lesser extent, vitamin E.

Issue 84

ROMIEU and colleagues, Instituto Nacional do Salud Publica, Cuernavaca, Morelos, Mexico, iromieu@correo.insp.mx, investigated antioxidant supplementation and lung function among children with asthma who are exposed to high levels of air pollutants.

Background: The study aim was to determine whether acute effects of ozone, nitrogen dioxide, and particulates could be attenuated by antioxidant supplementation.

Methods: Randomized double-blinded trial of 158 children in Mexico City were randomly given a daily supplement of vitamins (50 mg/day vitamin E plus 250 mg/day vitamin C) or placebo. They were followed for 18 months. Pulmonary function tests were carried out twice a week.

Results: In children with moderate to severe asthma in the placebo group, ozone levels on the previous day were significantly inversely associated with forced expiratory flow and peak expiratory flow. No such association between ozone levels and lung function was found in asthmatic children in the supplements group.

Conclusions: The results suggest that dietary supplementation with antioxidant vitamins may moderate the impact of air pollution on the airways of children with moderate to severe asthma.

Romieu I, Sienra MJJ, Ramirez AM, Tellez-Rojo MM, Moreno MH, Reyes-Ruiz NI, del Rio-Navarro BE, Ruiz-Nevarro MX, Hatch G, Slade R, Hernandez AM. Antioxidant supplementation and lung functions among children with asthma exposed to high levels of air pollutants. American Journal of Respiratory and Critical Care Medicine 166 (5): 703-709, Sep 2002.

Comment: Doctors ought to pay attention to these positive results achieved with fairly moderate supplement levels in these Mexican children, in view of the very serious asthma epidemic occurring in most western countries (in the UK 1 in 8 children suffers from asthma),

Issue 78

MANOCHA and colleagues, Natural Therapies Unit, Royal Hospital for Women, New South Wales, Australia, evaluated Sahaja yoga as adjunctive treatment for asthma patients who continue to experience asthma symptoms despite taking moderate to high doses of inhaled corticosteroids.

Background: Sahaja yoga is a traditional system of meditation that can have therapeutic benefits.

Methods:In this randomized, controlled, double-blind, parallel-group study, 59 adult asthma patients were assigned to a Sahaja yoga (n=30) or control (n=29) group. All subjects attended a 2-hour session once a week for 4 months. Study measurements, taken at the end of treatment and at a 2-month follow up, were: asthma-related quality of life (AQLQ; range 0-4); Profile of Mood States (POMS); airway hyperresponsiveness to methacholine (AHR); and a self-reported (diary card-based) asthma score (CAS; range 0-12) combining symptoms, use of bronchodilators and peak expiratory flow (PEF) rates.

Results: 20 subjects from the yoga group and 26 from the control group completed the end of treatment assessments. In the yoga group, improvement in the AHR at the end of treatment was 1.5 doubling doses greater than in the control group. Also in the yoga group, the AQLQ mood subscale score (difference 0.63) and the summary POMS score (difference 18.4) improved to a greater extent. However, differences in overall AQLQ score (0.41) and CAS (0.9) were not significant. No differences between the two groups could be detected at the 2-month follow-up assessment.

Conclusion: Sahaja yoga had some limited beneficial effects for asthma patients who had persisting symptoms despite inhaled steroid therapy. Further research would help uncover the mode of action of the observed effects and establish whether the intervention could prove clinically useful for patients with severe asthma.

Manocha R et al. Sahaja yoga in the management of moderate to severe asthma: a randomised controlled trial. Thorax 57 (2): 110-5. Feb 2002.

Comment: Research such as the above concerning yoga and breathing techniques are extremely importance, especially in light of the increasing asthma epidemic being experienced throughout much of the world.

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