Objective: To investigate the relationship between c-reactive protein (CRP) and blood pressure in a general population.
Methods: We randomly selected 3889 subjects aged 18 - 74 years stratified by gender and age in Baqiao, a rural area of Jiangsu Province. A standardized questionnaire was used to collect information on medical history, smoking, alcohol intake and use of medications. Blood pressure was measured by mercury sphygmomanometer. Serum CRP (hCRP) concentration was measured using a high sensitivity BNprosec immunonephelometric assay. Subjects were divided into 4 groups according to their interquartile range of CRP levers: group Q1 (men hCRP < 2.04 mg/L; women hCRP < 1.80 mg/L); group Q2 (men 2.04 mg/L ≤ hCRP < 3.01 mg/L; women 1.80 mg/L ≤ hCRP < 2.76 mg/L); group Q3 (men 3.01 mg/L ≤ hCRP < 4.14 mg/L; women 2.76 mg/L ≤ hCRP < 3.84 mg/L); and group Q4 (men 4.14 mg/L ≤ hCRP; women 3.84 mg/L ≤ hCRP).
Results: Systolic blood pressure (SBP, adjusted P = 0.016) and pulse pressure (PP, adjusted P = 0.003) of men and PP (adjusted P = 0.002) of women were increased in proportion to increased CRP levels. Diastolic blood pressure was not associated with CRP levels. Multiple stepwise regression analysis showed that logCRP was independently associated with SBP and PP in men and PP in women. hCRP was independently associated with hypertension in men. Compared with group Q1, male people in group Q4 faced a 40.4% (95% confidence interval: 4.9% - 87.9%) higher risk of hypertension.
Conclusions: hCRP was independently associated with PP in men and women, and SBP in men. hCRP was independently associated with hypertension in men but not in women in this study population.