AVP and Hypokalemia: The increased airway resistance that is associated with obstructive sleep apnea may also lead to nocturnal polyuria because of increases in renal sodium and water excretion that are mediated by elevated plasma atrial natriuretic peptide levels.[20] Diuresis via the inhibition of AVP can be caused by prostaglandin E-2, atrial natriuretic peptide, hypercalcemia, hypokalemia, lithium, and tetracycline.