The results of a study of twins by the Mailman School ofPublic Health at Columbia University suggest that an associationbetween asthma and posttraumatic stress disorder(PTSD) is not easily explained by common genetic factors.
The researchers looked at 3065 pairs of male twins whowere Vietnam veterans. The brothers had lived together duringchildhood, and both served active military duty. Theresearchers found that among all twins, those who experiencedthe most PTSD symptoms were also 2.3 times morelikely to have asthma, compared with those who experiencedfewer PTSD symptoms. The findings suggest that a patientwith asthma who experiences a traumatic event could benefitfrom professional help to avoid developing the disorder.
This new research helps bolster previous studies that supporta link between asthma and other anxiety disorders,including depression. The findings were reported in theNovember 15, 2007, issue of the American Journal ofRespiratory and Critical Care Medicine.
Researchers have long debated whether people whodevelop asthma have a genetic propensity to developallergies, and results of a study conducted by the NationalInstitutes of Health show that this may be the case. Theyfound that 56.3% of the asthma cases studied were attributedto preexisting allergies, or atopy, a condition thatresults from gene?environment interactions and can bemeasured by a positive skin test for allergens. The studywas published in the September 2007 online version of theJournal of Allergy and Clinical Immunology.
The researchers examined data from skin tests for 10allergens that involved about 10,500 participants. Theyfound that a positive skin test reaction to cat allergensaccounted for 29.3% of the asthma cases, followed by thefungus Alternaria at 21.1% and white oak at 20.9%.Although all of the 10 allergens were associated with asthma,only these 3 were "independently and positively"associated, said the researchers.
Children who eat more fish and vegetables might have achance of avoiding allergies or asthma, according to a Greekstudy. Researchers from the University of Crete, Heraklion,Greece followed 460 Spanish children from birth to age 6 andfound that those who ate more fish were the least likely todevelop allergies, compared with their peers who ate less fish.
They also found fewer instances of asthma among childrenwho consumed the most ?fruity? vegetables, such as eggplant,tomatoes, green beans, and zucchini (fruits and othertypes of vegetables had no similar effect). Parents of the participatingchildren answered questions on a variety of factorsthat affected a child?s risk of developing allergies, such asmother?s diet during pregnancy, breast-feeding, exposure tosecondhand smoke in the home, and family history of allergiesand asthma. After taking these and other factors intoaccount, the researchers found that diet was still stronglyrelated to a child?s asthma or allergy risk.
The researchers encouraged parents, especially thosewhose families carry one or more risk factors forallergy/asthma, to include these foods in their children?sdiets regularly. The findings were reported in the September2007 issue of the journal Pediatric Allergy and Immunology.
Although it is true that breast-feedingis best for babies, helping them stave offdiarrhea, ear infections, and incidents ofwheezing, the breathing benefits maybe lacking in children whose mothershave asthma.
Researchers from the University ofWisconsin-Madison and the ArizonaRespiratory Center at the University ofArizona in Tucson noted that "longerbreast-feeding in infancy is associatedwith improved lung function in later childhood,with minimal effects on airflow inchildren of nonasthmatic mothers."Whenthe mother has asthma, however, breastfeeding"demonstrates no improved lunggrowth and significant decrease in airflowslater in life."
Investigators looked at data from theChildren's Respiratory Study in Tucson,on 1246 infants enrolled at birth andmonitored through adolescence. Ofthese, 679 participants who had performedlung function testing betweenthe ages of 11 and 16 and had also disclosedcomplete information on infantfeeding practices were analyzed.Researchers found that those who werebreast-fed by mothers with asthma for 4months or longer "had a significantreduction in airflows" as adolescents.
They speculated that the breast milkof nonasthmatic mothers may containcertain elements that promote lungdevelopment that asthmatic mothersmay lack. The findings were reported inthe November 1, 2007, issue of theAmerican Journal of Respiratory andCritical Care Medicine.
F A S T F A C T : One in 3 asthma patients uses a rescue inhaler at least daily, and 73% use one at least once a month.