White blood cell count is positively associated with benign prostatic hyperplasia

Objectives To determine whether low-grade systemic inflammation is associated with prostatic enlargement/benign prostatic hyperplasia. Methods Prostate volume was measured by transrectal ultrasonography in 576 Japanese men. The association between prostate volume and routine clinical inflammatory markers (C-reactive protein level, white blood cell count, or the differential white cell count [neutrophils, lymphocytes, basophils, eosinophils, and monocytes]) were analyzed. Contributors to prostate volume were identified in univariate and multivariable linear regression models. Results Prostate volume was found to have a positive association with serum prostate-specific antigen level (P < 0.001), white blood cell count (P = 0.027) and absolute neutrophil count (P = 0.010). In univariate linear regression models, a large prostate volume was associated with older age, higher prostate-specific antigen, and higher white blood cell and neutrophil counts. A multivariable model adjusted for age, prostate-specific antigen, and C-reactive protein showed that the white blood cell count and the neutrophil count were independently associated with prostate volume. An increased white blood cell count was also associated with higher total International Prostatic Symptom Scores (P < 0.001). Conclusions White blood cell count seems to be associated with the degree of prostate enlargement and lower urinary tract symptoms. Chronic low-grade systemic inflammation might be involved in the etiology of benign prostatic hyperplasia.