Poor Americans More Likely to Have Respiratory Problems, Study Finds Despite improvements in air quality and other advances, low-income Americans more often have asthma, lung disease and related illnesses. Even when scientists controlled for the ill health effects of higher smoking rates among low-income individuals, a respiratory health gap persisted between rich and poor Americans.Credit...Susan L. Angstadt/MediaNews Group/Reading Eagle, via Getty Images May 28, 2021Updated 2:51 p.m. ET In recent decades, air quality has improved in the United States, smoking rates have plummeted and government safety regulations have reduced exposure to workplace pollutants. But rich and poor Americans have not benefited equally, scientists reported in a paper on Friday.