Sleep disordered breathing and hypertension.

Patients with sleep apnea may be at increased risk for cardiovascular disease. Recently, the link between hypertension and sleep apnea has been strengthened by findings of two large epidemiologic studies. Neurohumoral and hemodynamic responses to repetitive episodes of hypoxemia and apnea may offer a pathophysiologic basis for patients with sleep apnea having an increased risk for hypertension. Sympathetic, humoral, and cellular responses to sleep apnea over the long term may cause vascular dysfunction and consequent hypertension. These responses may be exacerbated by sleep deprivation, which occurs commonly in patients with sleep apnea because of poor sleep architecture. Patients with sleep apnea are often obese and may be predisposed to weight gain. Hence, obesity may further contribute to cardiovascular risk in this patient population. Alleviation of sleep disordered breathing may be accompanied by lower blood pressure in hypertensive patients with sleep apnea.