[Association between the level of high sensitivity C-reactive protein and risk of breast cancer among non-diabetic females: a prospective study in Kailuan group].

Objective To evaluate the association between high sensitivity C-reactive protein (hsCRP) and breast cancer incidence among the non-diabetic females in a large-scale cohort study in Kailuan group. Methods The Kailuan cohort was established on May 1, 2006. Baseline information on demography, lifestyle, medical history, and anthropometry, i.e., body height and weight, were collected during the baseline interview, and breast cancer incidence, mortality and other related outcome information were obtained by follow-up every two years and the related health condition database information were collected every year. Multivariable Cox proportional-hazards regression model was used to calculate the hazard ratios (HRs) and 95%CI (confidence interval) between the level of hsCRP at baseline interview and breast cancer incidence adjusted for age group, body mass index (BMI), marital status (married and single) and tobacco smoking (smokers and non-smokers) when appropriate. Results By Dec 31, 2011, a total of 17 402 females were enrolled in the cohort. There were 85 286 person-years of follow-up with a mean follow-up period of (58.81±4.52) months. A total of 75 incident breast cancer cases were collected. Subjects with the highest level (＞3 mg/L) of hsCRP at baseline interview were associated with a significantly increased risk of breast cancer (adjusted HR=1.80, 95%CI=1.03-3.15) compared with those with the lowest level (＜1 mg/L). Conclusions Elevated levels of hsCRP at baseline interview may be associated with an increased risk of breast cancer among non-diabetic females. Further follow-up and etiological exploration will help to evaluate the association between the hsCRP level and the risk of breast cancer more reliably. Key words: Breast neoplasms; High sensitivity C-reactive protein; Cohort studies; Epidemiology; Females