Researchers used pulmonary function tests and polysomnographic data in this analytical cross‐sectional study to examine the link between the presence and severity of obstructive sleep apnea (OSAS) and smoking. This analysis involved 333 patients who were diagnosed with OSAS or simple snoring by polysomnography and who applied to the Meram Medical Faculty Chest Diseases Sleep Laboratory. As per findings, heavy smoking was reported among patients with severe OSAS. Experts noted an increase in OSAS severity in association with increased smoking, this happened as a result of an increase in apnea‐hypopnea index (AHI) and a decline in oxygen saturation overnight both of which were consequent to increased smoking. A 15.3% increase in the AHI was observed in correlation with one unit increase in the package‐year. Source