BOSTON: Cockroaches are the leading cause of asthma in inner city neighborhoods, according to a study in Thursday's New England Journal of Medicine. The report, based on 476 asthmatic children living in New York, St. Louis, Baltimore, Chicago, Detroit and Washington, D.C., determined that cockroach saliva and droppings, which can trigger strong allergic reactions, causes nearly 25 percent of all asthma in poor city neighborhoods. Asthmatic children who are allergic to cockroaches and live in homes with high roach concentrations are three times as likely to require hospitalization and twice as likely to visit a doctor as other asthmatic children, the study found. Several public health departments have already launched cockroach control programs as a way to combat asthma. Get your roach motels now before the rush.