ATLANTA, may 24 (UPI) — about 9 percent of all U.S. asthma cases are made worse by work-related exposures, federal health officials say.

Work-related asthma includes work-exacerbated asthma — pre-existing or concurrent asthma worsened by factors related to the workplace environment — and occupational asthma, new onset asthma attributed to the workplace environment. Work-related asthma is a preventable occupational lung disease associated with serious adverse health and socioeconomic outcomes, officials at the Centers for Disease Control and Prevention said.

The Asthma Call-Back Survey collects detailed information on asthma, including data on asthma symptoms, healthcare utilization, medication use, knowledge of asthma, cost of asthma care, work-related asthma, comorbid conditions and complementary and alternative medicine use for asthma, the report said.

The 38,306 adults surveyed — who had been employed at one time and currently had asthma — represented an estimated 16 million adults in 38 states and the District of Columbia.

Of these, the estimated proportion who had work-related asthma was 9 percent. those with work-related asthma were most likely to be ages 45-64, blacks and other minorities.

The estimated proportion of ever-employed adults with current asthma who had work-related asthma was similar among men and women.

The findings were published in the Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report.