Trees and cats may cut childhood asthma risk, say studies

[Al-khiyal]

Trees may cut childhood asthma risk, says study

May 1, 2008 -- Living on a tree-lined street reduces a child's risk of developing asthma compared with life in a grey inner-city neighbourhood, according to researchers.

They found that asthma rates among four- to five-year-olds fell by almost a quarter for every 343 extra trees per square kilometre in an urban area.

In the UK, more than 5 million people suffer from the disease, according to the NHS. In adults it is more common among women than men and in 2005, 1,318 people died following an attack.

Asthma has increased by around 160% globally in the last two decades, although scientists are not sure what is causing this rise. Some have suggested that excessive cleanliness in the home is the cause, while another theory blames the increasing use of antibiotics.

The new analysis by researchers who studied data on asthma rates across New York suggests that a leafy suburban lifestyle goes some way to protecting children against the disease. By putting together data on the location of street trees in New York and data on children's health, Dr Gina Lovasi and her colleagues found that children in the greenest streets were least likely to develop asthma, although the degree of leafiness was not correlated with the number of more serious asthma attacks that led to hospitalisations. "Street trees were associated with a lower prevalence of early childhood asthmas," the team wrote in the Journal of Epidemiology and Community Health.

Professor Irwin McLean, who studies asthma at the University of Dundee, said it was a "very interesting study" but he urged caution in interpreting the results. "It shows that there is some correlation between suburban living and [a reduction in asthma]. That doesn't mean you should go out and plant a load of trees around your house if you want to stop your kids from getting asthma," he said.

He thinks high tree density is a marker for more suburban and richer neighbourhoods. The team tried to take this into account in their analysis, by factoring in things like the percentage of families in poverty and the percentage of black and latino residents in the area.

McLean added: "It is very difficult in environmental studies to dissect out one single triggering factor. There won't be a motorway running through a tree-lined suburb, for example, with all the pollution associated with that. The obvious thing people are going to think is, if I plant a load of trees around me that will protect me from asthma.

"That may not be the case. If you were living by the side of a motorway and you planted a forest around you, you are still going to get asthma - if the motorway is the cause of the asthma," he said.

[Bent_Bladi]

wow, see how beneficial trees are ... habibaty --- i love them

*hugs tree*

[Al-khiyal]

Early life exposure to cats may reduce risk of childhood allergies and asthma symptoms

May 22, 2008 (ScienceDaily) — A study released by researchers at the Columbia Center for Children's Environmental Health (CCCEH) at Columbia University's Mailman School of Public Health, shows that cat ownership may have a protective effect against the development of asthma symptoms in young children at age five. The study, published by the Journal of Allergy and Clinical Immunology, found that children with cats in the home were more likely to have made allergy-related antibodies to cats. At three years of age, children who had made antibodies to cats early in life were more likely to have wheeze, a respiratory symptom associated with asthma. However, by age five, the same children who had grown up with a cat were then found to be less likely to have wheeze.

This finding suggests that prolonged cat ownership and early life exposure to cats may have a protective effect against early asthma indicators, such as wheeze, as children reach age five. "While the study design does not allow us to recommend early cat ownership to prevent asthma, it does seem to indicate that avoidance of cats to prevent the development of asthma is not advised. However, once a child has asthma and is allergic to cats, the recommendation would still be to find a new home for the cat," said Matthew Perzanowski, PhD, assistant professor of Environmental Health Sciences at the Mailman School of Public Health and lead author and investigator on the research.

The study is part of a broader multi-year research project started in 1998, which examines the health effects of exposure of pregnant women and babies to indoor and outdoor air pollutants, pesticides, and allergens. The Center's prior research findings have shown that exposure to multiple environmental pollutants are associated with an increase in risk for asthma symptoms among children. For this study, the investigators controlled for other exposures that might have contributed to developmental problems such as socioeconomic factors and exposure to tobacco smoke and other environmental contaminants.

"Today's findings contribute to a further understanding of how the environment impacts child health," said Rachel Miller, MD, Irving Assistant Professor of Clinical Medicine at Columbia University; director, Asthma Project; associate director and lead physician scientist, DISCOVER Initiative, Mailman School's CCCEH; and senior author on the study. "They help us comprehend the complex relationship between early exposure to cats and the risk for asthma symptoms such as wheeze. The presence of cats in the home at a very early age seems to help reduce the risk of developing asthma. This is an important finding given the high prevalence of asthma in New York City and elsewhere."

Other investigators on the study include Frederica Perera, DrPH, Ginger Chew, ScD, Inge F. Goldstein, DrPH, Robin S. Garfinkel, PhD, Lori A. Hoepner, MPH, Adnan Divjan, Alina Johnson, and Thomas A. E. Platts-Mills, MD, PhD. The study was co-authored by researchers from the Columbia Center for Children's Environmental Health at Columbia University's Mailman School of Public Health and the Asthma and Allergic Diseases Center at the University of Virginia. The research was funded by the National Institutes of Health.

[Bent_Bladi]

and my pops said they'd make u lose a baby...

well, that's just another reason to get a kitty