Cardiovascular effects of transdermal nicotine in mildly hypertensive smokers.
Smoking potentiates the enhanced cardiovascular risk of hypertensive patients. Although nicotine replacement therapy is safe when used by healthy individuals to quit smoking, there is no evidence that nicotine replacement therapy is safe in hypertensive smokers. In this crossover, single-blinded, placebo-controlled study, we compared for 4 h the acute effects of transdermal nicotine on the mean arterial pressure (MAP) and heart rate (HR) of mildly hypertensive smokers treated with hydrochlorothiazide with the responses in normotensive smokers and nonsmokers monitored with Finapres and ambulatory blood pressure systems. The plasma concentrations of thromboxane B2 (TXB2, the stable breakdown product of TXA2) were also measured by ELISA to assess whether transdermal nicotine acutely affects TXA2 production. The use of 21-mg nicotine patches increased the MAP and HR in nonsmokers (from 94+/-4 mm Hg and 69+/-3 beats/min to 117+/-7 mm Hg and 83+/-3 beats/min, respectively; P < .05) as well as the MAP in normotensive smokers (from 83+/-4 to 106+/-7 mm Hg; P < .05). However, MAP and HR remained unaltered in hypertensive smokers after transdermal nicotine. Higher basal TXB2 levels were observed in hypertensive smokers compared with normotensive smokers and nonsmokers (2019+/-402 v 670+/-167 and 556+/-68 pg/mL, respectively; P < .05). Transdermal nicotine increased the TXB2 levels only in nonsmokers (P < .05). These data indicate that the use of transdermal nicotine in mildly hypertensive smokers is probably safe. Further studies involving other classes of hypertensive patients are warranted.
Tanus-Santos
J E
JE
Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Brazil.
Toledo
J C
JC
Cittadino
M
M
Sabha
M
M
Rocha
J C
JC
Moreno
H
H
D000279:Administration, Cutaneous; D000328:Adult; D001794:Blood Pressure / Q000187:drug effects*; D018592:Cross-Over Studies; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D009538:Nicotine / Q000008:administration & dosage*; D018722:Nicotinic Agonists / Q000008:administration & dosage*; D016037:Single-Blind Method; D016540:Smoking Cessation; D013928:Thromboxane A2 / Q000097:blood
D018722:Nicotinic Agonists; D013928:Thromboxane A2; D009538:Nicotine