title: Independent association between inflammatory markers (C-reactive protein, interleukin-6, and TNF-alpha) and essential hypertension.
abstract: High blood pressure (HBP) has been associated with elevated C-reactive protein (CRP), a marker of chronic mild inflammation. However, the association between HBP and other inflammatory markers, particularly interleukin 6 (IL-6) and tumour necrosis alpha (TNF-alpha), has not been evaluated in well-controlled studies. We examined the cross-sectional relationship between IL-6, TNF-alpha, and CRP and HBP in a random sample of 196 healthy subjects. All markers were measured in duplicate with high-sensitivity ELISA tests. Three blood pressure (BP) measurments were averaged for the analysis, and subjects with systolic BP >or=140 and/or diastolic BP >or=90 mmHg were considered hypertensive. Log binomial regression was used to estimate multivariate-adjusted prevalence ratios (PR) of HBP. Of the subjects, 40% (79) were hypertensive (mean age: 44 years; range 30-64). After adjustment for age, sex, body mass index, family history of HBP, and the level of the other inflammatory markers, subjects in the second (PR: 3.10, P=0.003), third (PR: 2.32; P=0.031), and fourth quartiles (PR: 2.30; P=0.036) of IL-6 were more than twice as likely to be hypertensive than those in the first quartile. Corresponding PR estimates for TNF-alpha levels were 1.41 (P=0.014) for the second; 1.59 (P=0.001) for the third; and 1.61 (P=0.025) for the fourth quartile. The CRP-HBP association was not statistically significant. Our results suggest that TNF-alpha and IL-6 could be independent risk factors for HBP in apparently healthy subjects. Nevertheless, the temporal relationship between elevated inflammation markers and HBP should be ascertained in prospective cohort studies.
authors.affiliation: Department of Preventive Medicine and Biometrics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA. lebautista@wisc.edu
authors.forename: L E
authors.initials: LE
authors.lastname: Bautista
authors.forename: L M
authors.initials: LM
authors.lastname: Vera
authors.forename: I A
authors.initials: IA
authors.lastname: Arenas
authors.forename: G
authors.initials: G
authors.lastname: Gamarra
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000032:analysis; D002097:C-Reactive Protein / Q000032:analysis; D003105:Colombia / Q000453:epidemiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000453:epidemiology; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis*
chemical_list: D015415:Biomarkers; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein