Study Links PSA Levels, Cholesterol
In healthy men, PSA levels rose 0.02 ng/mL for each 10 mg/dL increment in total and LDL cholesterol.
“We found the higher the cholesterol level, the higher the PSA level in otherwise healthy men,” said investigator Stephen Freedland, MD, associate professor of urology and pathology in the Duke Prostate Center at Duke University School of Medicine in Durham, N.C.
“It is really an interesting study because it says there is a link between serum cholesterol and what is going on within the prostate.”
Experimental and epidemiologic studies have suggested that cholesterol may play a role in prostate cancer development as well as progression. Duke investigators recently had observed that PSA levels were reduced in men after starting on statins.
This decline, they found, was proportional to the decline in LDL cholesterol resulting from the statin therapy. Until now, the relationship between PSA and cholesterol levels in the absence of statin therapy has been unknown.
The researchers conducted a longitudinal study with 1,214 men (mean age 60 years) prescribed a statin between 1990 and 2006 at the Durham VA Medical Center. All men were free of prostate cancer at baseline. None had undergone prostate surgery or taken any medications known to alter androgen levels at baseline; all had a PSA level between 0.1 and 10.0 ng/mL.
To be included in the study, the men were required to have at least one PSA determination and at least one of three confirmed cholesterol readings (total, LDL, or HDL cholesterol) within 24 months prior to starting statin therapy.
The men had a mean pre-statin PSA level of 1.5 ng/mL. The mean pre-statin level of total, LDL, and HDL cholesterol was 216, 144, and 40 mg/dL, respectively. After adjusting for age, ethnicity, and BMI, pre-statin PSA level was significantly associated with pre-statin total cholesterol and LDL concentrations, but not HDL, the investigators reported here at the American Urological Association annual meeting.
PSA levels increased 0.02 ng/mL for each 10 mg/dL increase in total and LDL cholesterol, according to the researchers. Among subjects with PSA values of 3.0 ng/mL or greater, every 10 mg/dL increase in total and LDL cholesterol was associated with a 0.07 and 0.08 ng/mL rise in PSA.
The study's lead author, Robert Hamilton, MD, a urology resident at the University of Toronto and former urological oncology fellow at Duke, observed: “These findings further suggest that what is heart-healthy (i.e., low cholesterol) may also be prostate-healthy, though future studies are needed to confirm these findings.”