asthmainfo

Most of the therapeutic benefit of inhaled fluticasone (flixotide) is achieved with a total daily dose of 100-250mcg. This is much less than the dose range of 200-2000mcg/day recommended in the British National Formulary.

Researchers in New Zealand carried out a meta-analysis of randomised controlled trials studying the efficacy of different doses of inhaled fluticasone. Data from over two thousand individuals in eight trials was reviewed.

The dose-response curve for this data began to plateau at a dose of around 100-200mcg per day, and the maximum effect is achieved at around 500mcg per day. Higher doses are likely to increase the occurrence of adverse side-effects without improving asthma control.

Where a person’s asthma is not controlled with fluticasone 500mcg/day, the addition of a long-acting beta-agonist is likely to be of greater benefit than a further increase in their inhaled steroid dose.

Reference: Holt, Suder, Weatherall et al. Dose-response relation of inhaled fluticasone propionate in adolescents and adults with asthma : meta-analysis. BMJ 2001; 323: 253-6.

Results from the world’s largest asthma study were recently published in the September issue of the European Respiratory Journal.

The European Community Respiratory Health Survey is a cross-sectional study involving 22 countries from Europe and around the world.

The Survey found marked variation in the prevalence of asthma in different countries. The highest rates of asthma were found in English-speaking countries such as Britain, Australia, New Zealand, Ireland and the United States. Low rates were found in the Mediterranean region, Eastern Europe, and countries such as Norway, Germany, Iceland, Algeria and India.

One finding from the survey that has received some publicity is the high prevalence of asthma in areas of higher paracetamol usage. This finding led to suggestions that paracetamol may contribute to the development of asthma.

However researchers found that this apparent association was largely due to the confounding factor of language. Paracetamol usage is far higher in those parts of the world that are English-speaking, and these are also the areas where asthma prevalence is highest. When researchers controlled for the “Anglophone effect”, much of this apparent association between paracetamol and asthma vanished.

Reference: Janson, Anto, Burney et al. The European Community Respiratory Health Survey; what are the main results so far ? European Community Respiratory Health Survey II. Eur Respir J 2001; 18: 598-611.

New treatments in asthma: anti-IgE

A large, multicentre trial has demonstrated the benefits of the immune-modifying drug rhuMAB-E25 or anti-IgE antibody. This randomised double-blind control trial compared subcutaneous anti-IgE with placebo in 546 patients with moderate to severe allergic asthma. Anti-IgE was given by subcutaneous injection every two to four weeks for a total of seven months.

Patients receiving anti-IgE had fewer asthma exacerbations than those in the placebo group, at the same time as achieving a greater reduction in inhaled conticosteroids.

Anti-IgE is currently being trialled in several research centres in New Zealand.

Reference: Soler, Matz, Townley et al. The anti-IgE antibody omalizumab reduces exacerbations and steroid requirement in allergic asthmatics. Eur Respir J 2001; 18: 254-61.

Anyone who uses an aerosol inhaler with benefit from using a spacer. The spacer – a valved plastic tube with a mouthpiece or mask at one end, and an opening for the inhaler at the other – makes the inhaler easier to use, and much more effective. It should be used with preventer medication, as well as for your reliever.

Using your spacer will slow down the speed of the aerosol, enabling more medicine to get into your lungs instead of getting left in your mouth and throat. It will reduce the chance of side-effects from preventer medication, such as hoarseness and thrush in the mouth. It will also help should you get short of breath – current evidence suggests that a spacer works at least as well as a nebuliser in most people with acute asthma.

To maintain the spacer’s effectiveness, wash it once a week in hot water with ordinary dish-washing liquid. (If you use Vicrom or Tilade, washing will need to be done more frequently.) Don’t rinse it, as the detergent helps to reduce static charge so that less of the medicine is drawn to the surface of the plastic. Since drying it with a cloth would create a static charge, let the spacer drip-dry. You do not need to wash the spacer between the use of your preventer and reliever.

Further information is in the Foundation’s booklet “Puffers and other devices”, available from your local Asthma Society, the Foundation’s office, or on www.asthmanz.co.nz

Will a dehumidifier help my asthma ?

If your asthma is triggered by dust mite waste, a dehumidifier won’t be of much benefit. In order to control the mites, humidity levels would have to be kept constantly under 40% relative humidity. This is extremely difficult to achieve in New Zealand, largely because of our high outdoor humidity. The best thing you can do to minimise exposure to dust mite allergen is to get effective barrier covers for your bedding as outlined in the September issue of Asthma and Respiratory News. Other recommended actions are outlined in the Foundation’s fact sheet on House Dust Mites (available on its website)

If mould spores trigger your asthma, you can reduce the likelihood of mould growing by keeping your home dry. Air the house well, and keep it warm inside – increasing inside temperatures reduces humidity. Use an externally vented extractor fan in the kitchen and bathroom, or an externally ducted range hood in the kitchen. Vent your clothes dryer outside too. Avoid using unflued gas or LPG heaters which add a lot of moisture to the air. If you decide to use a dehumidifier, choose a model with a high rate of water removal and – particularly if you’re going to place it in a bedroom – a low noise level.


You're in control with an asthma plan The focus of Asthma and Respiratory Week has been asthma plans. We have been promoting the child and self management plans to people with asthma, with the message You're in control with an asthma plan. Why this focus? Written plans are known to be effective in reducing asthma morbidity. The Foundation's plans are internationally recognised as a model and are readily available throughout New Zealand. We want them to be used as widely as possible, so that people with asthma can benefit from them. "In practical terms, the benefits can include fewer emergency trips to the doctor, less time missed at school, less broken sleep - and much better wellbeing for the child overall." Dr Barry, who chaired the committee which developed the resource, says that its symptom-based approach will be particularly useful for people with younger children with wheeze and cough who are too young to use peak flow meters. The plan and symptom diary are available free of charge, and parents and caregivers can request copies from their GP or Practice Nurse, affiliated Asthma Society, or the Foundation itself. Asthma New Zealand - web site Back to top of page Help for children with asthma The Asthma and Respiratory Foundation launched its new Child Asthma Plan and Symptom Diary on 20 June 2000. The new resource has been developed to help parents and caregivers learn more about their children's asthma and how to manage it effectively. "At present, many parents feel helpless in the face of asthma", according to Hawke's Bay paediatrician Dr David Barry. "By using the plan and diary, they can get a better handle on the asthma and how to deal with it. Dr Barry noted that there is further good news for parents of children with severe asthma, with prednisolone liquid (Redipred) becoming a fully subsidised medicine from 1 July for children under the age of 12. "The prednisolone liquid is a palatable alternative to prednisone, so it is great that it will be available free of charge for these children." Back to top of page
CALL FOR SMOKEFREE BARS, CLUBS AND RESTAURANTS
	(Media Release: 12 October 2001) The Asthma and Respiratory Foundation has issued a call for completely smokefree hospitality venues. The Supplementary Order Paper to the Smokefree Environments (Enhanced Protection) Amendment Bill was introduced to Parliament today, and the Foundation supports its intent to improve protection against second-hand smoke. However, the Foundation's Executive Director Jane Patterson says the proposed measures don't go far enough, and the Foundation is calling for all hospitality venues to be completely smokefree. "Second-hand smoke is bad for people's health," says Ms Patterson. "It's particularly hard on people with respiratory conditions - it's a trigger for 75% of people with asthma, so it really limits their options in terms of going out to clubs, bars and restaurants." "Asthma isn't a matter of choice, and smokefree public spaces shouldn't be either." Back to top of page
CONCERN ABOUT PARACETAMOL USE AND ASTHMA
	(Media Release: 10 September 2001) The Asthma and Respiratory Foundation of New Zealand has reiterated its advice regarding the use of over-the-counter pain-relievers, following the recent publicity concerning paracetamol and asthma. The Foundation advises that people with asthma should not use large doses of paracetamol on a regular basis without discussing this with their family doctor. The use of aspirin-based pain relievers is also not recommended for those with asthma as some people can experience a severe asthma attack after taking aspirin. A large international survey which studied the possible causes of asthma in 22 countries, including New Zealand, showed that in English-speaking countries there was a positive association between paracetamol sales and asthma prevalence in adults and 13-14 year-old children. The Foundation's Medical Director, Professor Ian Town, commented that "As there is no evidence that paracetamol causes severe episodes of asthma, occasional doses should not be a problem." References Janson C et al. Eurpean Respiratory Journal 2001; 18: 598-611 Newson RB et al. European respiratory Journal 2000; 16: 817-23 Shaheen et al. Thorax 2000; 55: 266-270. Back to top of page
Cannabis Inquiry 2001
	Cannabis Inquiry 2001 : Executive Summary of the combined submission made to the Parliamentary Health Select Committee by the Thoracic Society of Australia and New Zealand (TSANZ) and the Asthma and Respiratory Foundation of New Zealand (ARFNZ); released July 2001 The TSANZ and ARFNZ are primarily concerned with issues of respiratory health in New Zealanders, included those relating to smoking. The therapeutic use of cannabinoids, and the effects of cannabis on mental health or social behaviour are beyond the scope of this submission. The majority of cannabis use is by inhalation of cannabis smoke. The smoke contains not only the active pharmacological ingredient tetrahydrocannabinol (THC), but also a range of toxic materials similar to that obtained from tobacco smoke. There is unequivocal evidence that the short-term health effects of smoking cannabis are identical to those of tobacco smoke : airway inflammation is provoked, and symptoms of acute bronchitis occur. Evidence obtained from a recent large New Zealand investigation has shown that respiratory symptoms and adverse changes in lung function occur at the same frequency as in tobacco smokers of 10+ cigarettes per day. Other studies confirm that combined cannabis and tobacco use have additive adverse effects. The long-term effects of cannabis smoking are likely to be just as harmful as tobacco. This includes the development of chronic bronchitis and emphysema, and possibly lung cancer. Adequate data to validate this statement will not be available for another 25-30 years, given the very slow progress of these diseases associated with smoking. Passive inhalation of cannabis is also likely to be very harmful. Recommendations 1.Any changes in the present law related to cannabis use should be based on a clear understanding of its harmful effects. The burden of ill-health among New Zealanders and associated costs will increase if consumption increases. As for tobacco, every step should be taken to reduce rather than encourage consumption of both substances. 2.Cannabis possession should continue to be prohibited by law but penalties relating to its use by individuals should be civil rather than criminal. The commercial cultivation, import, export, supply and sale of cannabis should continue to be criminal offences. Knowing what we now know about the serious harmful effects of tobacco smoke (but too late), it is unlikely that it would ever obtain legal status were it to be introduced for the first time. This should govern our approach to the use of cannabis. Current government strategies to achieve a smoke-free society ought not to be compromised by contradictory attitudes to cannabis. Inhaling smoke of any description is harmful! Although at present the use of cannabis decreases in adults over the age of 25, this demographic pattern may change if cannabis is decriminalised or legalised, thus potentially contributing to an increase in the incidence of respiratory disease in the longer term. 3.Public health education should include the message that the adverse respiratory health effects of smoking cannabis are identical to those of smoking tobacco. The perception persists that cannabis use is comparatively free from harmful effects. Health promotion strategies in schools and elsewhere should aim to dispel this myth. Objective evidence confirms that the health effects of cannabis in the lungs are identical to those of tobacco. Back to top of page
Peak flow meters
	(Asthma and Respiratory News - September 2001) The Foundation has received enquiries about whether we endorse the Pocket Peak Flow Meter recently introduced onto the NZ market. We don't - our logo appears only on the Breath Alert peak flow meter distributed by Air Flow Products. The Foundation's position is that people with asthma should have access to reliable peak flow meters which meet AS/NZS 4237:1994, the Australian and New Zealand Standard for peak flow meter accuracy (which provides for variation of no more than +/- 7.5%). We have asked Medsafe to take action to ensure that this is the case. In the meantime we recommend that when choosing a peak flow meter from the range available, people confirm that it meets this Standard. Back to top of page