Relationship of supine hypertension to baroreflex-cardiovagal and baroreflex-sympathoneural dysfunction in chronic autonomic failure

skin vascular resistance by +44% (6.2 + 1 to 8.9 + 1 units, p1⁄40.001) with unchanged calf muscle vascular resistance (36.2 + 3 to 32.8 + 3 units, p1⁄4ns). In preliminary microneurographic studies, the differential regional vascular responses to hookah smoking were accompanied by increased sympathetic outflow to skin but not skeletal muscle. All cardiovascular parameters were unchanged in nine non-smoking time control studies. In conclusion, these data in overtly healthy young adult chronic hookah smokers document a striking discordance between perceived risk and the acute cardiovascular toxicity of hookah smoking. While perceived to be innocuous, each hookah smoking session constitutes a potent cardiovascular stimulant that is at least if not more potent than previously reported for cigarettes. Further studies are indicated to elucidate the underlying neural and vascular mechanisms, which overtime could accelerate development of hypertension.