ASSOCIATION OF RESPIRATORY SYMPTOMS AND LUNG-FUNCTION IN YOUNG-ADULTSWITH USE OF DOMESTIC GAS APPLIANCES

Background There is evidence from some studies that people living in h omes with gas stoves and other unvented gas appliances experience more respiratory symptoms than those who use other fuels for cooking and h eating, but other studies have found no such association. We have inve stigated whether the use of gas appliances is associated with an incre ased risk of respiratory symptoms and whether sensitisation to common environmental allergens modifies any such association. Methods A strat ified random sample of 15 000 adults aged 20-44 years, living in three towns in East Anglia, UK, were sent a questionnaire on asthma and hay fever. From those who responded, a random sample of 1864 were invited to complete an extended questionnaire that included questions on use o f gas appliances, to give blood samples for measurements of total IgE and specific IgE to common allergens, and to undergo tests of respirat ory function. 659 women and 500 men agreed to an interview. The associ ation of the use of gas appliances with respiratory symptoms, total Ig E, specific IgE, and respiratory function was assessed by logistic and multiple regression models. Findings Women who reported they mainly u sed gas for cooking had an increased risk of several asthma-like sympt oms during the past 12 months including wheeze (odds ratio 2.07 [95% C I 1.41-3.05]), waking with shortness of breath (2.32 [1.25-4.34]), and asthma attacks (2.60 [1.20-5.65]). Gas cooking increased the risk of symptoms more in women who were atopic than in non-atopic women but th e difference did not reach significance (p>0.05). Women who used a gas stove or had an open gas fire had reduced lung function (forced expir atory volume in 1 s [FEV(1)]) and increased airways obstruction (FEV, as a percentage of forced vital capacity) compared with women who did not. These associations were not observed in men. Interpretation In Ea st Anglia, the use of gas cooking is significantly associated with sub jective and objective markers of respiratory morbidity in women but no t in men. Women may be more susceptible than men to the products of ga s combustion or they may have greater exposure to high concentrations of these products because they cook more frequently than men.