Second, natriuretic peptide theory (Berendes et al., 1997) indicated that the natriuretic factors, such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), may play important roles in the occurrence and development of CSWS, leading to an increase in sodium excretion and urine volume. This evidence concerns the gene NPPA and developmental and/or epileptic encephalopathy with spike-wave activation in sleep.