130 patients with narcolepsy-cataplexy (mean ± SD age 20 ± 10 yrs, 69% male) and 117 controls (22 ± 6.9 yrs, 62% male) were recruited and tested for human leukocyte antigen (HLA)-DQB1*0602 status, hyperoxia hypercapnic (change in minute ventilation (δV'(E))/carbon dioxide tension (δP(CO(2))) L·min(-1)·mmHg(-1)) and hypoxic (δV'(E) /change in arterial oxygen saturation measured by probe oximetry (δS(p,O(2))) L·min(-1) per %S(p,O(2))) responsiveness, and by spirometry.