CAT and chronic obstructive pulmonary disease: Similarly, Mexican women exposed to biomass smoke have been reported to have more respiratory symptoms,37 a finding corroborated by a study conducted in China and reporting that COPD patients exposed to biomass smoke alone had higher CAT scores than did those exposed to tobacco alone or occupational hazards alone (17.5 ± 6.3 vs. 15.3 ± 6.3 vs. 15.2 ± 6.3; p < 0.05).38