The relation of serum parathyroid hormone and serum calcium to serum levels of prostate-specific antigen: A population-based study

Experimental and clinical data implicate calcium and parathyroid hormone (PTH) in the development of prostate cancer. However, epidemiologic data on the role ofthe se variables in prostate health are sparse. We examined the relationship between serum levels ofca lcium, PTH, and prostate-specific antigen (PSA), an established marker ofp rostate growth, in a large, population-based study using multivariate linear regression. We studied 1,273 men in National Health and Nutrition Survey 2005 to 2006 who were ≥40 years of age and who were without clinical prostate cancer. Adjusted for age, race, body mass index, and serum levels of25-hydroxyvitamin D, serum levels ofPT H were significantly positively correlated with serum PSA (P = 0.01). Serum levels ofP TH and calcium each were correlated significantly with free PSA (P = 0.05 and 0.008, respectively). The percentage ofmen who had elevated serum levels ofPTH (PTH, ≥66 pg/mL) was significantly greater among African American men (19.2 versus 9.6%, P = 0.04). Compared with men whose PTH was at the lower end ofthe reference range, the predicted PSA for men with a PTH of 66 pg/mL was increased 43%. These findings support the hypothesis that serum calcium and serum PTH stimulate prostate growth in men without clinical prostate cancer and have implications for the use of PSA as a screening tool for prostate cancer.