Hypertension in Obese Black Women is Not Caused by Increased Sympathetic Vascular Tone

Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease

Claudia E. Ramirez¹  Amy C. Arnold²  Alejandro Marinos³  Alfredo Gamboa⁴  Brock A. Preheim⁴  Cyndya A. Shibao⁴  Luis E. Okamoto⁴  Andre Diedrich⁴  Jorge E. Celedonio⁴  Italo Biaggioni⁴ 

[1] Meharry Medical College, Nashville, TN;Penn State College of Medicine, Hershey, PA;University of Cincinnati, OH;Vanderbilt University School of Medicine, Nashville, TN;

关键词: black;    hypertension;    obesity;    sympathetic nervous system;    women;   

DOI  :  10.1161/JAHA.117.006971

来源: DOAJ

【 摘 要 】

BackgroundBlack women have one of the highest prevalence rates of hypertension and obesity in the United States. We previously reported that sympathetic activation induced by obesity is a significant contributor to hypertension in white patients. It is unknown whether sympathetic activity similarly contributes to hypertension in obese black women. Methods and ResultsWe studied 42 obese women (16 white, body mass index 36±4 kg/m2, 44% with hypertension; 26 black, body mass index 35±4 kg/m2, 46% with hypertension). Antihypertensive medications were discontinued for 2 weeks before the day of the study. All patients underwent complete autonomic blockade with trimethaphan at a dosage of 4 mg/min. Resting sympathetic activity determined from muscle sympathetic nerve recordings was similar between obese black women with hypertension and those with normotension. In whites, sympathetic activity was elevated in obese patients with hypertension compared with normotension; the decrease in mean arterial blood pressure produced by trimethaphan was greater in obese white patients with hypertension compared with those with normotension (−26.8±9.7 mm Hg versus −14.8±7.9 mm Hg, P=0.02). In contrast, there was no difference in the depressor responses induced by trimethaphan between obese black women with hypertension and those with normotension (−15.5±10.5 mm Hg versus −12.3±10.2 mm Hg, P=0.45). Mean arterial blood pressure remained elevated in obese blacks with hypertension compared with those with normotension during trimethaphan infusion (83.7±15.0 mm Hg versus 71.7±9.8 mm Hg, P=0.02). Heart rate increased similarly with trimethaphan between white (P=0.11) and black (P=0.76) women with hypertension and normotension. ConclusionsThese findings suggest that sympathetic activity does not contribute to hypertension in obese black women and provide further evidence for racial differences in hypertension mechanisms.

【 授权许可】

Unknown