We observed that AA, but not EA, cigarette smokers with the Val/Val genotype had significantly higher systolic and diastolic blood pressure readings throughout the session. In previous studies, the Val/Val genotype has been associated with higher blood pressure in mainly EA populations (57, 58). To our knowledge, the influence of the COMT Val158Met polymorphism on blood pressure regulation in cigarette smokers has not been examined. The underlying mechanism for the association of the Val/Val genotype with higher blood pressure in AA smokers is unclear. Previous studies have shown that AAs excrete less sodium and are more salt-sensitive than EAs (59–61). DA plays an important role in blood pressure regulation, primarily by influencing sodium excretion from the kidneys. Other mechanisms, such as the noradrenergic system, may also contribute to our findings, although the role of COMT Val158Met polymorphism on NE function has not been well described. Higher systolic and diastolic blood pressure in AA cigarette smokers with the Val/Val genotype may have noteworthy health and treatment implications, especially given the cardiovascular risks associated with smoking (62).
