Sixteen-year longitudinal changes in serum prostate-specific antigen levels: the olmsted county study.
OBJECTIVE
To determine the distribution of longitudinal changes in serum prostate-specific antigen (PSA) levels from a population-based sample of men.


METHODS
In this prospective cohort study, a random sample of Olmsted County, Minnesota, men aged 40 to 79 years in 1990 were followed up biennially from January 1, 1990, through August 29, 2007. Serum PSA levels were determined at each examination, and men were censored for follow-up with a diagnosis of prostate cancer or treatment for benign prostatic hyperplasia. The empirical distributions of annual percent change and annual absolute change in serum PSA level were calculated and tabulated, including the median and 75th and 95th percentiles.


RESULTS
For men with PSA measurements 2 years apart, the median annual percent change in serum PSA level was 4.83% and the 95th percentile was about 49.76%. The variability in estimated annual change decreased with increasing time between assessments, with a 95th percentile of 21.82% after 8 or more years between assessments. Although the median absolute change per year increased with increasing age, the median percent change per year was fairly consistent across age groups.


CONCLUSIONS
These data demonstrate that, with shorter intervals between assessments, greater variability should be expected. These distributions should prove helpful to patients and clinicians in interpreting changes in serum PSA levels observed in typical clinical practices.
Department of Research and Evaluation, Southern California Permanente Medical Group, Pasadena, CA, USA.
Steven J
SJ
Jacobsen
Debra J
DJ
Jacobson
Michaela E
ME
McGree
Jennifer L
JL
St Sauver
George G
GG
Klee
Cynthia J
CJ
Girman
Michael M
MM
Lieber
D000328:Adult; D000368:Aged; D006801:Humans; D008297:Male; D008875:Middle Aged; D008910:Minnesota; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood*; D011470:Prostatic Hyperplasia / Q000097:blood* / Q000175:diagnosis; D011471:Prostatic Neoplasms / Q000097:blood* / Q000175:diagnosis
D017430:Prostate-Specific Antigen