Is acute high-dose secondhand smoke exposure always harmful to microvascular function in healthy adults?

Prev Cardiol. Long-term exposure to secondhand smoke (SHS) is associated with impaired vascular function. The authors investigated the vascular and blood pressure (BP) reactions to acute SHS exposure. Twenty-five healthy nonsmoking adults underwent a 1-hour exposure to SHS (mean fine particulate matter < 2.5 μm level = 315 ± 116 μg/m(3) ). Microvascular endothelial-dependent vasodilatation (EDV) (EndoPAT, Itamar Medical, Caesarea, Israel) and aortic hemodynamics/compliance (SphygmoCor, AtCor Medical, West Ryde, Australia) were measured before and after the SHS exposure with BP measured every 15 minutes during and for a 24-hour period before and after the exposure. SHS exposure did not change EDV, aortic hemodynamics, arterial compliance, or 24-hour BP. However, diastolic BP significantly increased during the SHS exposure period by 3.4 ± 5.6 mm Hg. Our brief SHS exposure did not impair microvascular endothelial function or arterial compliance in healthy nonsmoking adults, but brachial diastolic BP increased.