Asthma increases the chances of clinically relevant obstructive sleep apnea in adulthood, a prospective study finds. Participants with preexisting asthma had a nearly 40 percent increased risk for new OSA compared with those without asthma, according to the research published in JAMA. The risk of OSA increased along with asthma duration found the researchers who studied the in-laboratory overnight polysomnography results of 81 patients.