It is not established whether there is an association between high NTproBNP (N-Terminal Fragment of the Prohormone Brain-Type Natriuretic Peptide - NT-proBNP) and Apnea-Hypopnea Index (AHI) and whether it can be used as a predictive value for the severity of sleep apnea in these patients, which we will seek an answer in the present study. The gene discussed is NPPB; the disease is Sleep apnea.