Plasma adrenomedullin and obstructive sleep apnea

BACKGROUND: Obstructive sleep apnea (OSA) is associated with hypertension. The vasorelaxing peptide adrenomedullin (ADM) may counteract effects of OSA-induced release of vasopressor substances. METHODS: Plasma ADM levels were measured at 9:30 PM, 2:00 AM (after 4 to 5 h of untreated OSA), and 6:00 AM (after 4 h of continuous positive airway pressure treatment) in 15 OSA patients and in 10 controls. RESULTS: Baseline ADM levels were similar in the OSA and control groups (28.7 +/- 6.7 v 27.7 +/- 6.4 pg/mL, respectively), did not change overnight in either group, and were not affected by continuous positive airway pressure. CONCLUSIONS: OSA does not exert any significant acute or chronic effects on plasma ADM levels.