Letters Section Editor: Stephen J. Lurie,
MD, PhD, Senior Editor.
In Reply: Drs Hussain and Karnath point out
the possibility of an association between OSA and both pulmonary hypertension
and right ventricular dysfunction. Although systemic circulatory changes have
been extensively examined, studies of pulmonary hemodynamics in patients with
OSA, and the effects of treatment on these measures, are limited. One important
impediment to such studies is the invasive approach needed for measurements
of pulmonary arterial pressure, particularly in patients with OSA in whom
obesity may impair the quality of noninvasive echocardiographic estimates
of pulmonary artery pressure. Other confounding issues that obscure a clear
identification of a causal interaction between OSA and both pulmonary hypertension
and right ventricular dysfunction include considerations related to body mass
index, coexisting obesity-hypoventilation syndrome, pulmonary disease,1 and other comorbidities.
Shamsuzzaman ASM, Gersh BJ, Somers VK. Mechanisms and Treatment of Obstructive Sleep Apnea—Reply. JAMA. 2004;291(5):557. doi:10.1001/jama.291.5.557-c