Are baseline levels of IL-6 and CRP associated with the risk of developing hypertension in initially normotensive women?
Baseline CRP, but not IL-6, is strongly and independently associated with the risk of developing hypertension in women after adjusting for body mass index.
Although markers of systemic inflammation may have a role in the development of hypertension, supportive clinical data remain limited. We, therefore, examined interleukin (IL)-6 and C-reactive protein (CRP) in a nested case-control study of 400 women developing hypertension and an equal number of age-matched normotensive control subjects during 10 years of follow-up as part of the Women's Health Study. All of the women initially had nonhypertensive blood pressure values and no history of diagnosis or treatment. Subjects provided self-reported risk factors, and IL-6 and CRP were measured from baseline bloods. Case subjects reported elevated systolic (>or=140 mm Hg) or diastolic (>or=90 mm Hg) blood pressure, newly diagnosed hypertension, or initiating antihypertensive treatment during follow-up. In crude-matched models, IL-6 and CRP quartiles were each strongly associated with hypertension risk (both Ps for trend 0.05). Therefore, after multivariate adjustment and strong confounding by body mass index, IL-6 was weakly associated and CRP strongly associated with hypertension risk. In models simultaneously examining IL-6 and CRP, only CRP remained strongly associated with an increased risk of hypertension.
Sesso et al. (Tue,) studied this question.