OBJECTIVETo explore the interaction of C-reactive protein (CRP) and hypertension on the risk of carotid plaque.

METHODSA survey for CVD risk factors and a direct measurement of carotid arteries with B-mode ultrasound imaging were performed in a population consisting of 866 subjects in the Peking university residential community in 2002. Carotid plaque was regarded as the endpoint while elevated CRP and hypertension were treated as the impact factors.

RESULTS(1) The partial correlation coefficient of blood pressure levels with CRP quartiles was 0.089 (P = 0.008); (2) The prevalence of carotid plaque in males showed an upward trend with elevated CRP quartiles while male-specific CRP quartile was independently associated with the prevalence of carotid plaque (P < 0.01). (3) The prevalence of carotid plaque in the group of people with both hypertension or elevated CRP was 50.4%, being significantly higher than those in other groups (P < 0.01). (4) When compared with the group of people without hypertension or elevated CRP, the odds ratio increased by 2.0 times in the group of people with both hypertension and elevated CRP (P < 0.01). (5) The odds ratio of interaction between hypertension and elevated CRP was 1.792 (95% CI: 1.189-2.701) (P = 0.005).

CONCLUSIONThere was an interaction between hypertension and elevated CRP on the rates of carotid plaque prevalence seen in our study. Data also showed that more benefit might be gained from controlling both hypertension and inflammation for preventing plaque.