Sleep-disordered breathing (SDB) is often encountered in morbid obesity (MO) in conjunction with insulin resistance (IR). Aminoterminal pro-brain natriuretic peptide (NT-proBNP) is a promising marker for left ventricular dysfunction (LVD) in MO. We sought to explore the factors that may influence the relationships of SDB and IR with NT-proBNP in MO women. We performed a cross-sectional pilot study involving 110 asymptomatic MO (44.5+/-0.7 kg/m2) young women. SDB risk was assessed using a modified version of the Berlin Questionnaire (BQ). IR was assessed using the homeostasis model assessment (HOMA) index and adiponectin levels. LVD was assessed using NT-proBNP and echocardiograms. In this study, NT-proBNP levels and LVD increased significantly along the BQ strata. Multiple regression analysis identified BQ and log-transformed HOMA as the independent variables predicting as much as 48.0% of the variability of logNT-proBNP. In conclusion, NT-pro-BNP levels are independently predicted by SDB and IR in asymptomatic MO women. Larger prospective studies are warranted.