All posts in Asthma

Inhalers linked to higher odds of diabetes in asthma and COPD patients

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Asthma and chronic obstructive pulmonary disease (COPD) patients who are treated with inhaled corticosteroids may face a significantly higher relative risk for both the development and progression of diabetes, new Canadian research suggests. The warning stems from an analysis of data involving more than 380,000 respiratory patients in Quebec. Inhaler use was associated with a 34 percent increase in the rate of new diabetes diagnoses and diabetes progression, the researchers found. What's more, asthma and COPD patients treated with the highest dose inhalers appear to face even higher diabetes-related risks: a 64 percent jump in the onset of diabetes and a 54 percent rise in diabetes progression. “High doses of inhaled corticosteroids commonly used in patients with COPD are associated with an increase in the risk of requiring treatment for diabetes and of having to intensify therapy to include insulin,” the study team noted in a news release.

Based on their results, researchers from McGill University and the Lady Davis Research Institute at Jewish General Hospital in Montreal suggest “patients instituting therapy with high doses of inhaled corticosteroids should be assessed for possible hyperglycemia and treatment with high doses of inhaled corticosteroids limited to situations where the benefit is clear.”

Lead investigator Samy Suissa colleagues report their findings in the most recent issue of the American Journal of Preventive Medicine.

The research team wrote that despite the fact that inhalers are recommended for use solely by the most severely ill COPD patients, they are typically prescribed for a much broader pool that amounts to about 70 percent of all COPD patients. The authors found that more than 30,000 of the COPD/asthma patients in their study developed a new diagnosis diabetes over the course of five and a half years of treatment. This amounted to a diabetes onset rate of a little more than 14.2 out of every 1,000 inhaler patients per year.

“These are not insubstantial numbers,” Suissa said. “Over a large population,m the absolute numbers of affected people are significant.” In addition, in the same timeframe nearly 2,100 patients already diagnosed with diabetes before using inhalers experienced a worsening of their disease that ultimately required upgrading their diabetes care from pills to insulin shots.

Dr. Stuart Weiss, an endocrinologist with the New York University Medical Center, suggested that concern should be directed more at the underlying causes of both diabetes and asthma/COPD rather than at inhalers themselves. “I would say that a lot more attention should first be paid to the lifestyle choices, dietary-wise, that lead to the pro-inflammatory conditions that raise the risk for both type 2 diabetes as well as COPD and asthma,” said Weiss, who is also a clinical assistant professor at the NYU School of Medicine in New York City. “We don't look at asthma as being a dietary condition, but it absolutely is. Which means that in terms of diabetes and asthma risk, the body is reacting to similar stresses brought about by the over-consumption of overprocessed foods and the lack of consumption of green vegetables.”

Noting that the underlying risk for both conditions is similar, Weiss said he suspected the steroids themselves should not bear all the blame. “What may be more at the root of this problem,” he said, “is the fact that those who are most at risk for diabetes are the same people who have the worst asthma and COPD that requires steroid treatment in the first place.” “Yes, we do know that steroids increase insulin resistance and that people treated with steroids require more aggressive diabetes management,” he conceded. “But if we don't generally take an approach that deals with the poor quality of food that people are routinely consuming, the incidence of both these diseases will continue to go up at a dramatic rate.”

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Poor Diet Metabolism, Lack of Exercise Increases Asthma Risk in Kids

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Metabolic syndrome is a cluster of risk factors which can result in heart disease and diabetes. Researchers have now found that poor diet and lack of exercise that lead to an imbalance in metabolism may also increase a child's risk of developing asthma.

Dr. Giovanni Piedimonte and researchers from West Virginia University School of Medicine analyzed data from nearly 18,000 children aged 4 to 12 years who were taking part in the Coronary Artery Risk Detection in Appalachian Communities (CARDIAC) project. Factors considered included triglyceride levels and evidence of acanthosis nigricans, which are raised patches of brown skin that are often biomarkers for insulin resistance.

The team also considered body mass index or BMI, and almost 21% of the children were considered obese. Fourteen percent of the children had asthma.

The researchers found that asthma prevalence among the children was strongly associated with certain symptoms of metabolic syndrome including dyslipidemia and abnormal glucose metabolism, but not weight status. Although those who were obese were more likely to have asthma, even children of a healthy weight who had imbalanced metabolism were at increased risk.

Certain metabolic factors participate in the asthma disease process by contributing to inflammation of the airways in the lungs and hyperreactivity (contraction of smooth muscle in the bronchial walls), says Dr. Piedimonte. He says that strict monitoring and control of triglyceride and glucose levels early in life may play a role in the management of chronic asthma in children.

Dr. Piedimonte would like to see the findings used as further support for universal lipid screening in children. “The rationale is that by using selective screening, we would have missed over a third of children with significant genetic dyslipidemia,” he said.

Both poor diet – one lacking in antioxidants but high in fat – and inadequate exercise play a role in the metabolic syndrome, a group of risk factors that increase the risk for coronary artery disease, stroke, and type 2 diabetes. The goal of treatment is often weight loss (if overweight), a minimum of 30 minutes of daily moderate intensity exercise, and a lowering of cholesterol, blood pressure and blood sugar through diet or medication.

Source reference:
Cottrell L, et al “Metabolic abnormalities in children with asthma” Am J Respir Crit Care Med 2010; DOI: 10.1164/rccm.201004-0603OC.

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Tylenol linked to asthma

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A new study shows that adolescents who take acetaminophen, better known as Tylenol, have a higher risk of asthma, allergic nasal conditions and the skin disorder eczema.

Acetaminophen is widely viewed as a very safe drug—one reason why hospitals use it routinely as a painkiller instead of aspirin or ibuprofen. The major problem associated with it is liver damage caused by overdoses. Recently, however, there has been a growing drumbeat about possible dangers from the drug. One study, for example, found that acetaminophen increased the risk of hearing loss in men. And some others have hinted that the drug is linked to asthma in newborns whose mothers used the drug during pregnancy and in young children exposed to it.

The new findings were reported in the American Journal of Respiratory and Critical Care Medicine by researchers in the International Study of Asthma and Allergies in Childhood. The team, headed by epidemiologist Richard Beasley of the Medical Research Institute in Wellington, New Zealand, gave written questionnaires to 322,959 13- and 14-year-olds in 50 countries exploring their use of acetaminophen, other drugs, and asthma symptoms. They were also shown a video containing five scenes of clinical asthma and asked whether they had experienced any symptoms similar to those shown. About 73% of the teens said they had used acetaminophen at least once in the previous year and 30% said they had used it monthly.

Taking into account maternal education, smoking, diet and siblings, the team found that those subjects who had used the drug at least once per year were 43% more likely to have asthma, while those who used it at least monthly were 2.5 times as likely to suffer from the condition. The risk of rhinoconjunctivitis (a severe nasal congestion) was 38% higher for those who used it once per year and 2.39 times as high for those who used it at least monthly. The comparable increases in risk for eczema were 31% and 99%, respectively.

Overall, the increased risk of asthma associated with acetaminophen was 41%, the authors found. That could, at least in part, explain why there has been an increase in the prevalence of asthma in the 50 years since the drug was introduced. Given the widespread use of the drug, it could also represent a large public health problem.

But—and it is a very big but—the study shows only an association, not causality. That could only be determined by a randomized clinical trial, which the authors recommend. Furthermore, the study relies on the recall of teenagers. Recall is notoriously inaccurate in adults, and it is probably worse in adolescents, clouding the results. For the time being then, you can probably continue to feel comfortable giving the drug to your children.

In a statement, McNeil Consumer Healthcare, which manufactures Tylenol, said that the drug “has over 50 years of clinical history to support its safety and effectiveness” and that no clinical trial has demonstrated that the drug causes asthma.

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How does ethnicity affect asthma prevalence?

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A study of UK schoolchildren has revealed that Black Africans, Indians and Bangladeshis have a similar or lower prevalence of asthma than White children, while Black Caribbean and Mixed Black Caribbean/White boys are more likely to have asthma. Researchers writing in the open access journal BMC Pediatrics studied the occurrence of asthma, investigating ethnic differences in risk factors.

Melissa Whitrow and Seeromanie Harding from the Social and Public Health Sciences Unit of the Medical Research Council, UK, used data taken from 51 London schools to investigate a random selection of 11-13 year old pupils. The final sample for analysis included 1219 children who identified themselves as 'White UK', 933 'Black Caribbean', 1095 'Black African', 459 'Indian', 215 'Pakistani', 392 'Bangladeshi' and 299 'Mixed White UK and Black Caribbean'.

According to Whitrow and Harding, “Social and environmental factors may influence risk of asthma through early life exposures regulating the allergic inflammatory response and/or later life exposures to allergens. A positive association between body mass index (BMI) and asthma has also been reported. We aimed to investigate the influence of these factors on ethnic differences in asthma prevalence”.

The researchers found that a family history of asthma and psychological well-being were consistent correlates for asthma regardless of ethnicity. Less than six years of residence in the UK had an independent protective effect for Black Caribbeans and Black Africans, possibly reflecting continuing protection from early life exposures in their home countries. A gender difference was observed for Indians and Bangladeshis, with less asthma in girls than boys. Speaking about these results, the authors said, “These findings point to early protective influences which are not properly understood. International comparisons could provide useful insights into prevention of asthma, for ethnic minority children and for all children”.

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High Fat Diet Can Make Asthma Symptoms Worse

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Avoid eating meals high in fat, especially if you suffer from asthma, urges Australian researchers after finding the fat leads to inflamed breathing passages and hinders drug interventions.

Lisa Wood, PhD, research fellow and lecturer in the biomedical sciences and pharmacy department of Hunter Medical Research Institute, at the University of Newcastle, led the study with a team of researchers and presented their findings at ATS 2010, the international meeting of the American Thoracic Society, in New Orleans.

The researchers challenged 14 non-obese asthmatics and 16 obese participants to a high-fat diet (1,000 calories with 52%/60g of fat) of burgers and fried potatoes and another group of 16 non-obese asthmatics to eat a low-fat yogurt diet (200 calories, 13%/3g fat). “Induced sputum samples were collected at baseline and at 4 hours” according to the study's abstract.

“Subjects who had consumed the high-fat meal had an increase in airway neutrophils and TLR4 mRNA gene expression from sputum cells, that didn't occur following the low fat meal, ” said Wood.

She continued, “The high fat meal impaired the asthmatic response to albuterol. In subjects who had consumed a high fat meal, the post-albuterol improvement in lung function at three and four hours was suppressed.”

The researchers were surprised to find that the fatty diet also impacted the effectiveness of asthma medications, like albuterol. Wood added, “This is the first study to show that a high fat meal increases airway inflammation, so this is a very important finding. The observation that a high fat meal changes the asthmatic response to albuterol was unexpected as we hadn't considered the possibility that this would occur.”

It's unclear how and why fat not only inflames the airways but also prevents known asthma therapies from working. The researchers intend to design “more studies to investigate this effect. We are also investigating whether drugs that modify fat metabolism could suppress the negative effects of a high fat meal in the airways. If these results can be confirmed by further research, this suggests that strategies aimed at reducing dietary fat intake may be useful in managing asthma.”

Whether you have asthma or not is becoming increasingly more important for heart and now lung health to avoid the fat.

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Blackcurrants show anti-asthma potential

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Study details

Led by Dr Roger Hurst, the New Zealand-based researchers examined the effects of the anthocyanidin-rich blackcurrant extract on cells from lung tissue. The researchers focussed on a compound called eotaxin-3 or CCL26, which is expressed in the lungs after stimulation of the cells by cytokine interleukin-4 (IL-4). According to their findings, epigallocatechin (EGC) worked in conjunction with other natural immune responses to suppress CCl26 expression, and therefore inflammation. Furthermore, these actions were distinct from the inflammation-reducing activity of anthocycanins, said the researchers.

“The bioavailability of plant-derived phytochemicals, although not the focus of this particular study, is an important consideration in the design of a functional food,” wrote Dr Hurst and his co-workers. “In particular, blackcurrant- derived proanthocyanidins mainly (480 per cent) consist of high molecular weight polymers, however, recent findings show that these large proanthocyanidins can be broken down by chemical, enzymatic and/or resident microflora in various regions of the digestive tract to release small oligomers and monomers that are easily absorbed, such as EGC and epicatechin. “Therefore, it is feasible that blackcurrant metabolites, such as EGC, may be able to modulate eotaxin expression in lung tissue,” they added.

Plant & Food Research's Dr Roger Hellens, Genomics Science Group Leader, will be presenting at the upcoming NutraIngredients Antioxidants 2010 Conference in Brussels on the subject of super Vegetables. 

Source: Molecular Nutrition and Food Research
“Blackcurrant proanthocyanidins augment IFN-gamma-induced suppression of IL-4 stimulated CCL26 secretion in alveolar epithelial cells”
Authors: S.M. Hurst, T.K. McGhie, J.M. Cooney, D.J. Jensen, E.M. Gould, K.A. Lyall, R.D. Hurst

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