[The prospective study of association between C-reactive protein and hypertension in community population].

Objective: The aim was to explore the association between high-sensitivity C-reactive protein level at baseline and hypertension in follow-up periods in a Chinese cohort.

Methods: We analyzed data from a cohort established in "Prevention of metabolic syndrome and multi-metabolic disorders in Jiangsu province" in April 2000. A follow-up investigation was carried out for those whose follow up time met 5 years in June 2006. A total of 2035 persons completed investigation and hs-CRP was tested. Subjects with normal baseline blood pressure were classified into four groups(514, 498, 515 and 508 subjects in each group) according to quartiles of hs-CRP level (<1.3, 1.3-1.9, 2.0-3.2 and ≥ 3.3 mg/L). The relationship between the risk of hypertension and baseline level of hs-CRP were analyzed using Cox proportional hazards regression model.

Results: The median of follow up time was 6.39 years among the 2035 subjects (926 males and 1109 females). Hypertension incidence was 2378/100 000 person-years, 2942/100 000 person-years, 3693/100 000 person-years and 4390/100 000 person-years in hs-CRP < 1.3, 1.3-1.9, 2.0-3.2 and ≥ 3.3 mg/L groups respectively. Compared to the group of hs-CRP < 1.3 mg/L, the relative risk (RR) (95%CI) of hypertension in groups of hs-CRP 1.3-1.9, 2.0-3.2 and ≥ 3.3 mg/L was 1.22 (0.87-1.72), 1.43 (1.03-2.00), 1.70 (1.21-2.41) respectively, adjusted for sex, age, baseline blood pressure, BMI, smoking, alcohol drinking, physical activity and family history of myocardial infarction and diabetes.When stratified by quartiles of baseline blood pressure, the incidence of hypertension in each group increased with level of hs-CRP.In the group whose baseline SBP < 110 mm Hg (1 mm Hg = 0.133 kPa) , compared to the group of hs-CRP < 1.3 mg/L, RR (95%CI) were 2.24 (1.32-4.03), 2.57 (1.57-4.57) and 3.57 (2.54-5.90) in hs-CRP 1.3-1.9, 2.0-3.2 and ≥ 3.3 mg/L groups respectively.In the group whose baseline DBP < 65 mm Hg, RR (95%CI) were 1.78 (1.03-3.24), 2.74 (1.63-4.93) and 4.13 (2.35-7.27) respectively.

Conclusion: Inflammation was an important process in the development of hypertension.