Hemoglobin in normal range, the lower the better?—Evidence from a study from Chinese community-dwelling participants

摘要

Objective: To examine the association between hemoglobin (Hb) levels and cardiovascular risk factors in a large community-dwelling cohort. Methods: A total of 4,186 women and 4,851 men were enrolled in the study. Data on personal history, physical examination and biochemical parameters were collected. Subjects were categorized by gender and divided into different group according to the level of Hb or blood pressure, and the association between Hb levels and cardiovascular risk factors was examined using Pearson’s correlation analysis. Results: In both men and women even with normal Hb level, tertiles of Hb levels were positively associated with body mass index (BMI), total-cholesterol (TC), triglyceride (TG), uric acid (UA), diastolic blood pressures (DBP) and fasting plasma glucose (FPG) (all P=0.000 in men and women). Furthermore, significantly increased incidence of hyperuricemia (P=0.000 both in men and women) and obesity (P=0.000 both in men and women) were observed with the gradually increased Hb level. In addition, Pearson’s correlation analysis revealed obvious correlation between Hb level and various cardiovascular risk factors including blood pressure and UA. Binary logistic regression analysis further demonstrated that the level of Hb was an important risk factor for elevated blood pressure (OR =1.216; 95% CI: 1.138-1.293, P=0.000 in men; OR =1.287; 95% CI: 1.229-1.363, P=0.000 in women). Conclusions: Increasing Hb levels, even in subjects with normal level were associated with increasing prevalence of cardiovascular risk factors, suggesting that a slightly low Hb level might be beneficial to Chinese community-dwelling individuals.