Persuasive data implicates obstructive sleep apnea (OSA) in the development of hypertension, arrhythmias, vascular dysfunction and cardiac disease. Webber et al demonstrated an increased prevalence of obstructive sleep apnea (OSA) among firefighters exposed to the WTC disaster, and our group has demonstrated a similar prevalence of screen positive for OSA among 2500 law enforcement officers present at Ground Zero. The relationship between OSA and risk of cardiac disease involves similar pathophysiologic pathways including inflammation and impaired vascular reactivity.