Observed effect of age and body mass index on total and complexed PSA: analysis from a national screening program

Effect of ageing and body mass index on prostate-specific antigen levels among Chinese men in Singapore from a community-based study

OBJECTIVE To assess the effect of ageing and body mass index (BMI) on prostate-specific antigen (PSA) among Chinese men from the results of the 2005 Prostate Awareness Week in Singapore. SUBJECTS AND METHODS In all, 2714 men participated in the programme, consisting of 2431 Chinese, 114 Malays, 117 Indians and 52 'others'. Of these, 2410 Chinese men who had a PSA level of <20 ng/mL and were aged >50 years but <80 years were included in the analysis. Height and weight were used to calculate the BMI. The relationship between age and PSA levels was analysed using linear regression and bivariate correlation, and the associations among different groups of BMI and PSA levels were analysed using analysis of variance and covariance. RESULTS PSA levels were significantly correlated with age (correlation coefficient, r = 0.27, P < 0.001). Analyses showed a significant inverse association between PSA level and BMI; mean PSA levels decreased with increasing BMI for both standards (standard classification; geometric mean, GM, PSA of 1.08, 1.06, 0.96, 0.83 ng/mL for a BMI of <18.5, 18.5-24.9, 25-29.9 and > or =30 kg/m(2), respectively, P trend <0.01; and for Asian classification, GM PSA 1.08, 1.09, 0.96, 0.91 ng/mL for a BMI of <18.5, 18.5-22.9, 23-27.5 and > or =27.5, respectively, P trend <0.001). There were significant differences (P < 0.05) in the age-adjusted GM PSA levels for the groups with BMI <25 (1.05 ng/mL) and BMI > or =25 kg/m(2) (0.97 ng/mL). Similarly, there were significant differences (P < 0.05) in the age-adjusted GM PSA levels in those with a BMI of <30 (1.03 ng/mL) and > or =30 kg/m(2) (0.85 ng/mL). CONCLUSION These data suggest that the BMI in Chinese men in Singapore is significantly associated with PSA levels, especially among the obese men aged 70-79 years.

Associations of lifestyle and physiologic factors with prostate-specific antigen concentrations: evidence from the National Health and Nutrition Examination Survey (2001-2004)

Studies suggest inverse associations between obesity and prostate-specific antigen (PSA). However, there is little evidence whether factors related to obesity, including lifestyle (diet and physical activity) and physiologic factors (insulin resistance and metabolic syndrome), influence PSA. We used dietary, physical activity, and serum PSA, insulin, glucose, and lipid data for men >40 years from the National Health and Nutrition Examination Survey (2001-2004; N = 2,548). Energy, fat, and carbohydrate intakes were estimated from a 24-hour dietary recall. Men were considered as having metabolic syndrome based on the Adult Treatment Panel III criteria. Leisure-time physical activity and doctor-diagnosed hypertension were self-reported. Body mass index was calculated from measured weight and height. We computed the geometric mean PSA (ng/mL), adjusted for age, race, and body mass index, by tertile of energy, fat, and carbohydrate intake and level of physical activity, and among men with and without insulin resistance and metabolic syndrome in the whole population and by race. The geometric mean PSA (95% confidence interval) among men in the lowest tertile of energy was 1.05 (0.97-1.1) relative to 0.85 (0.8-0.9) in the highest tertile (P = 0.0002) in the whole population. The PSA concentrations were lower among overweight men with higher versus lower energy intake (P = 0.001). The PSA concentrations in men with insulin resistance was lower [0.87 (0.8-0.9)] relative to men without insulin resistance [0.98 (0.9-1.1)] at P = 0.04. All associations were in similar directions within racial subgroups. No associations were observed between the other lifestyle and physiologic factors. Additional studies are required to confirm these results and to investigate the potential mechanisms that may explain these relationships.

Obesity is a significant risk factor for prostate cancer at the time of biopsy

OBJECTIVES

Studies suggest obesity is associated with decreased prostate cancer risk. We hypothesized obesity is biologically associated with increased risk, although this is obscured owing to hemodilution of prostate-specific antigen (PSA) and larger prostate size.

METHODS

We retrospectively studied 441 consecutive men undergoing prostate biopsy between 1999 and 2003 at two equal access centers within the Veterans Affairs Greater Los Angeles Healthcare System. We estimated the association between obesity (body mass index >or= 30 kg/m(2)) and positive biopsy and Gleason >or=4+3 using logistic regression analysis adjusting for multiple clinical characteristics.

RESULTS

A total of 123 men (28%) were obese and 149 men (34%) had cancer. Median PSA and age were 5.7 ng/mL and 63.9 years, respectively. Obese men had significantly lower PSA concentrations (P = .02) and larger prostate volumes (P = .04). Obesity was not significantly related to age (P = .19) or race (P = .37). On univariate analysis, obesity was not associated with prostate cancer risk (odds ratio [OR] 1.13, 95% confidence interval [CI] 0.73-1.75, P = .58). However, after adjusting for multiple clinical characteristics, obesity was associated with significantly increased prostate cancer risk (OR 1.98, 95% CI 1.17-3.32, P = .01). After multivariable adjustment, there was no significant association between obesity and high-grade disease (P = .18).

CONCLUSIONS

Without adjustment for clinical characteristics, obesity was not significantly associated with prostate cancer risk in this equal-access, clinic-based population. However, after adjusting for the lower PSA levels and the larger prostate size, obesity was associated with a 98% increased prostate cancer risk. These findings support the fact that current prostate cancer screening practices may be biased against obese men.

Relationship between serum prostate-specific antigen levels and components of metabolic syndrome in healthy men

OBJECTIVES

To assess the correlation between age, body mass index, systolic and diastolic blood pressure (BP), triglycerides, high-density lipoprotein (HDL), and fasting blood glucose (FBG) and the serum prostate-specific antigen (PSA) level and to determine the significant factors for predicting the serum PSA level in men with a low risk of prostate cancer.

METHODS

A total of 38 356 healthy male employees of the Korea Electric Power Corporation who were <60 years old and had a serum PSA level of <4 ng/mL were enrolled in this study from January 2002 to December 2006. Their BP, body weight, and body height were measured, and biochemical analyses of FBG, triglycerides, HDL, and serum PSA were performed.

RESULTS

The mean age +/- standard deviation was 44.38 +/- 7.90 years; the mean serum PSA level was 0.89 +/- 0.51 ng/mL; and the incidence of metabolic syndrome was 25.8%. On univariate analysis, significant correlations were noted between the serum PSA level and body mass index, diastolic BP, HDL, and FBG (P < .05). Multiple logistic regression analyses using 4 percentiles (10th, 25th, 75th, and 90th percentile) of the serum PSA level revealed trends for a positive association between older age and diastolic BP and the serum PSA level. The body mass index, HDL, and FBG correlated negatively with the serum PSA level.

CONCLUSIONS

These results suggest that the serum PSA level is significantly influenced by age and some components of the metabolic syndrome (obesity, diastolic BP, HDL, and FBG).

Obesity and oncological outcome after radical prostatectomy: impact of prostate-specific antigen-based prostate cancer screening: results from the Shared Equal Access Regional Cancer Hospital and Duke Prostate Center databases

OBJECTIVE

To indirectly test the hypothesis that prostate-specific antigen (PSA)-based screening is biased against obese men due to haemodilution of PSA, and thus results in delayed diagnosis and poorer outcome beyond the biological link between obesity and aggressive prostate cancer.

PATIENTS AND METHODS

We sought to examine the association between body mass index (BMI) and the outcome of radical prostatectomy (RP) separately for men with PSA-detected cancers (cT1c) or with abnormal digital rectal examination (DRE) findings (cT2/T3), and stratified by year of treatment, using two large databases. We conducted a retrospective cohort study of 1375 and 2014 men treated by RP between 1988 and 2007 using the Shared Equal Access Regional Cancer Hospital (SEARCH) and Duke Prostate Center (DPC) databases. We evaluated the association between BMI and adverse pathological features and biochemical progression, using logistic regression and Cox proportional hazards models, adjusting for several clinical characteristics, respectively. Data were examined as a whole and as stratified by clinical stage (cT1c vs cT2/T3) and year of surgery (>or=2000 vs <2000).

RESULTS

In both cohorts a higher BMI was associated with high-grade disease (P <or= 0.02) and positive surgical margins (P < 0.001) and these results did not vary by clinical stage. A higher BMI was significantly associated with biochemical progression (P <or= 0.03) in both cohorts. When stratified by clinical stage, obesity was significantly related to progression in both cohorts among men with T1c cancers (P <or= 0.004) but not in men with cT2/T3 cancers (P > 0.3). Among men with T1c disease, the association between BMI and biochemical progression was limited to men treated in 2000 or later (P <or= 0.002) and was not apparent in men treated before 2000 (P > 0.4).

CONCLUSIONS

Obese men with PSA-detected cancers and treated with RP since 2000 were at significantly greater risk of biochemical progression, while obese men treated before 2000 or diagnosed with an abnormal DRE were not at significantly greater risk of progression. These findings support the hypothesis that current PSA-based screening is less effective at finding cancers in obese men, leading to more aggressive tumours at diagnosis. Lowering the PSA threshold for biopsy among obese men might help to improve outcomes among this high-risk group.

Inverse relationship between obesity and serum prostate-specific antigen level in healthy Japanese men: a hospital-based cross-sectional survey, 2004-2006

OBJECTIVES

To confirm an inverse relationship between obesity and serum prostate-specific antigen (PSA) levels in Japanese men with a smaller body mass index (BMI) than white and African-American men.

METHODS

We analyzed 5246 apparently healthy Japanese men aged >20 years who visited our medical center for a health checkup from January 2004 to December 2006. The men were divided into 6 groups by age decade, and the BMI was categorized into 5 groups. The body fat percentage (BFP) was also used and was grouped into quartiles. The Mantel-Haenszel chi(2) test was used to check for trends in proportions of subjects with abnormal PSA values for each cutoff point (2.5 and 4.0 ng/mL) in these groups. The relationships between the PSA levels and BMI or BFP were examined using multivariate analysis.

RESULTS

The median age, BMI, BFP, and PSA level was 46 years, 23.2 kg/m(2), 21.5%, and 0.78 ng/mL, respectively. The proportion of subjects with an abnormal PSA value increased significantly with age (P for trend < .0001); however, no trends were found across the BMI or BFP categories. The geometric mean PSA level increased significantly with age (P for linear trend < .0001) and decreased with BMI and BFP categories (P for linear trend = .001 and P for linear trend = .002, respectively).

CONCLUSIONS

Our findings have demonstrated an inverse relationship between obesity and PSA levels even in Japanese men with a low prevalence of obesity, such as was previously reported for American men. Therefore, in prostate cancer screening, obesity, which can affect the accuracy of PSA testing, independent of race and ethnicity, should be taken into account.

Body composition and serum prostate-specific antigen: review and findings from Flint Men's Health Study

Recent studies have suggested that obesity is associated with lower serum prostate-specific antigen levels, perhaps influencing the recommendation for prostate biopsy and potentially explaining part of the observed poorer prognosis among obese men. African-American men have the greatest rates of prostate cancer and are more likely to die of the disease, making early detection a priority in this group. We present findings from the Flint Men's Health Study, a study of African-American men, that are consistent with most studies suggesting that overweight men have prostate-specific antigen levels that are 0.15 to 0.30 ng/mL lower than those who are not overweight. We have coupled our results with a systematic review of publications in this area.

Obesity and screening PSA levels among men undergoing an annual physical exam

BACKGROUND

Prior reports suggest that obesity is inversely associated with screening prostate-specific antigen (PSA) levels and may reduce screening sensitivity.

METHODS

We evaluated data on 10,623 men screened for prostate cancer during an annual physical examination program administered by EHE International, Inc., between 1/1/2004 and 6/30/2006. Of these, 3,623 men returned for additional physical exams during this period. We used multivariate linear regression analyses to determine whether higher BMI was inversely associated with PSA, and whether BMI, or change in BMI, was associated with change in PSA levels over time. We also developed a theoretical model for the effect of obesity on PSA levels in which increased plasma volume in the obese dilutes PSA levels.

RESULTS

After control for age and race/ethnicity, higher BMI was associated with lower PSA levels; men with a BMI > or =40 had a geometric mean PSA level 0.14 ng/ml lower than men with a BMI <25 (P < 0.001). Prospectively, BMI at initial screening and change in BMI over 2 years were not associated with change in PSA or PSA velocity. Our theoretical model accurately predicted observed PSA levels and suggests that a screening PSA of 4.0 ng/ml in normal weight and overweight men corresponds to 3.5 ng/ml in obese men and 3.1 ng/ml in morbidly obese men.

CONCLUSION

Across the study population, increased BMI was significantly inversely associated with lower PSA. Based on a theoretical model in which increased plasma volume in the obese dilutes PSA levels we propose new cut-points for a positive screening test.

Body mass index, prostate-specific antigen, and digital rectal examination findings among participants in a prostate cancer screening clinic

OBJECTIVES

Prior studies suggested obese men have lower prostate-specific antigen (PSA) values. However, the association between body mass index (BMI) and digital rectal examination (DRE) findings and the association between weight at age 18 and adult PSA or DRE findings have not been examined. We sought to study the associations among BMI and weight at age 18 and adult PSA and DRE findings.

METHODS

We analyzed data from 535 participants in a free prostate cancer-screening program in North Carolina held in September 2006. The associations among BMI and weight at age 18 and abnormal DRE and PSA levels were determined using multivariate logistic and linear regression models, respectively.

RESULTS

A total of 391 men (73%) were overweight or obese, of whom 144 (27%) were obese. Mean +/- standard deviation and median age were 61.4 +/- 10.5 and 61 years, respectively; and 294 men (55%) were black, 219 (41%) white, and 22 (4%) neither black nor white. On multivariate analysis, higher BMI was significantly associated with lower PSA values (P = 0.03) but was not significantly associated with DRE findings. Weight at age 18 was not significantly related to adult PSA levels or DRE findings.

CONCLUSIONS

In a multiethnic cohort of participants in a prostate cancer-screening clinic, obesity was associated with decreased PSA levels. We found no significant associations among BMI and DRE findings or weight at age 18 and adult PSA levels or DRE findings. The current data suggest that the PSA cut-points used to recommend biopsy need to be adjusted for the degree of obesity.

Obesity and mortality in men with locally advanced prostate cancer: analysis of RTOG 85-31

BACKGROUND

Greater body mass index (BMI) is associated with shorter time to prostate-specific antigen (PSA) failure following radical prostatectomy and radiation therapy (RT). Whether BMI is associated with prostate cancer-specific mortality (PCSM) was investigated in a large randomized trial of men treated with RT and androgen deprivation therapy (ADT) for locally advanced prostate cancer.

METHODS

Between 1987 and 1992, 945 eligible men with locally advanced prostate cancer were enrolled in a phase 3 trial (RTOG 85-31) and randomized to RT and immediate goserelin or RT alone followed by goserelin at recurrence. Height and weight data were available at baseline for 788 (83%) subjects. Cox regression analyses were performed to evaluate the relations between BMI and all-cause mortality, PCSM, and nonprostate cancer mortality. Covariates included age, race, treatment arm, history of prostatectomy, nodal involvement, Gleason score, clinical stage, and BMI.

RESULTS

The 5-year PCSM rate for men with BMI <25 kg/m(2) was 6.5%, compared with 13.1% and 12.2% in men with BMI > or =25 to <30 and BMI > or =30, respectively (Gray's P = .005). In multivariate analyses, greater BMI was significantly associated with higher PCSM (for BMI > or =25 to <30, hazard ratio [HR] 1.52, 95% confidence interval [CI], 1.02-2.27, P = .04; for BMI > or =30, HR 1.64, 95% CI, 1.01-2.66, P = .04). BMI was not associated with nonprostate cancer or all-cause mortality.

CONCLUSIONS

Greater baseline BMI is independently associated with higher PCSM in men with locally advanced prostate cancer. Further studies are warranted to evaluate the mechanism(s) for increased cancer-specific mortality and to assess whether weight loss after prostate cancer diagnosis alters disease course.

IGF-1 and IGFBP-3: Risk of prostate cancer among men in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial

IGF-1 and IGFBP-3 may influence risk of prostate cancer through their roles in cellular growth, metabolism and apoptosis, however, epidemiologic results have been inconsistent. The role of obesity in prostate cancer risk is not clearly understood, but hyperinsulinemia-related increases in bioactive IGF-1 levels, associated with obesity, could be a component of the relationship between the IGF-axis and prostate cancer. We conducted a nested case-control study in the prospective Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial to examine associations between IGF-1 and IGFBP-3 and risk of prostate cancer. A total of 727 incident prostate cancer cases and 887 matched controls were selected for this analysis. There was no clear overall association between IGF-1, IGFBP-3 and IGF-1:IGFBP-3 molar ratio (IGFmr) and prostate cancer risk, however, IGFmr was associated with risk in obese men (BMI > 30, p-trend = 0.04), with a greater than 2-fold increased risk in the highest IGFmr quartile (OR 2.34, 95% CI 1.10-5.01). Risk was specifically increased for aggressive disease in obese men (OR 2.80, 95% CI 1.11-7.08). In summary, our large prospective study showed no overall association between the insulin-like growth factor axis and prostate cancer risk, however, IGFmr was related to risk for aggressive prostate cancer in obese men.

Obesity and prostate cancer: epidemiology and clinical implications

OBJECTIVES

Both obesity and prostate cancer (PCa) are epidemic in Western society. Although initial epidemiological data appeared conflicting, recent studies have clarified the association between obesity and PCa. Therefore, we sought to review the epidemiological data linking obesity and PCa with an emphasis on the clinical implications and how to improve outcomes among obese men.

METHODS

A PubMed search using the keywords "prostate cancer" and "obesity" was performed. Relevant articles and references were reviewed for data on the association between obesity and PCa.

RESULTS

Recent data suggest obesity is associated with reduced risk of nonaggressive disease but increased risk of aggressive disease. This observation may be explained in part by an inherent bias in our ability to detect PCa in obese men (lower PSA values and larger sized prostates, making biopsy less accurate for finding an existent cancer), which ultimately leads to increased risk of cancer recurrence after primary therapy and increased PCa mortality. Despite this detection bias potentially contributing to more aggressive cancers, multiple biological links also exist between obesity and PCa including higher estradiol, insulin, free IGF-1, and leptin levels, and lower free testosterone and adiponectin levels, all of which may promote more aggressive cancers.

CONCLUSIONS

The association between obesity and PCa is complex. Emerging data suggest obesity increases the risk of aggressive cancer, while simultaneously decreasing the risk of more indolent disease. This is likely driven by both "biological" and "nonbiological" causes. Simple changes in clinical practice patterns can reduce the impact of nonbiological causes and may help improve PCa outcomes among obese men.

Body mass index does not predict prostate-specific antigen or percent free prostate-specific antigen in men undergoing prostate cancer screening

OBJECTIVES

Body mass index (BMI) may alter serum prostate specific antigen (PSA) and percent free PSA (%fPSA) and may mask the risk of prostate cancer. We investigated the relationship between BMI and PSA or %fPSA.

MATERIALS AND METHODS

Height, weight, PSA and %fPSA were assessed in 616 consecutive screened men without prostate cancer. Continuously coded and categorised BMI was studied. Statistical analyses consisted of ANOVA, linear regression, bivariate and partial correlations.

RESULTS

Median age was 57 years. Median PSA was 1.0 and median %fPSA was 26. Median BMI was 25.8 kg/m(2). Neither continuously coded nor categorised BMI correlated with either PSA or %fPSA in unadjusted or age-adjusted analyses (all p values > or = 0.3).

CONCLUSIONS

Body mass index does not affect PSA or %fPSA in men without known prostate cancer, who undergo prostate cancer screening. Therefore, PSA or %fPSA-based screening or early detection efforts do not require an adjustment for BMI.

Obesity is negatively associated with prostate-specific antigen in U.S. men, 2001-2004

BACKGROUND

Recent studies have shown a negative association between body mass index (BMI) and prostate-specific antigen (PSA), a commonly used serum marker for the detection and diagnosis of prostate cancer. We have examined the association between several anthropometric measures and PSA in a nationally representative sample of men.

METHODS

We analyzed data from the 2001-2004 National Health and Nutrition Examination Survey. Participants in this study were men ages >or=40 years without previously diagnosed prostate cancer who had PSA measured. Height, weight, waist circumference, BMI, triceps skinfold, subscapular skinfold, and calculated total body water were examined categorically by quintiles using multiple linear regression models. All tests of significance were two sided.

RESULTS

Among white men, we report a trend for decreasing PSA with increasing weight, BMI, waist circumference, triceps skinfold thickness, and calculated total body water. Among Mexican American men, we found a trend for decreasing PSA with increasing BMI, and among black men we found a trend for decreasing PSA with increasing triceps thickness. None of the interaction terms between race/ethnicity and any of the anthropometric measures were statistically significant. Controlling for age and race/ethnicity in the multiple linear regression model, we found moderate declines in PSA with a 1 SD increase in BMI [5.9% decrease (95% confidence interval, -9.0% to -2.8%) in geometric mean PSA per 5.2-unit increase], weight [5.9% decline (-8.8% to -2.8%) per 17.7-kg increase], waist circumference [6.6% decline (-9.4% to -3.6%) per 13.4-cm increase], triceps skinfold [5.4% decline (-8.9% to -1.8%) per 6.4-mm increase], and calculated total body water [5.7% decline (-8.9% to -2.4%) per 6.5-liter increase].

CONCLUSION

Our population-based, nationally representative results expand the validity of previous studies on obesity and PSA. Higher weight, BMI, waist circumference, triceps skinfold, and total body water are associated with moderately lower PSA values. A prospective study is needed to verify whether this association affects the accuracy of the PSA test in obese men.

Relationship between serum prostate-specific antigen levels and body mass index in healthy younger men

OBJECTIVES

To understand further the physiologic characteristics of serum prostate-specific antigen (PSA) concentrations in healthy younger men.

METHODS

A total of 2032 men, 20 to 39 years old, who visited our hospital for a routine health checkup were entered into the study. Pearson correlation coefficients were determined to evaluate the association between serum PSA and clinical parameters. Because of the log-normal distribution, the serum PSA levels were log-transformed for analysis.

RESULTS

Although the relationships were weak, significant negative correlations were noted between serum PSA and body weight (r = -0.107, P <0.001), body mass index (BMI; r = -0.131, P <0.001), aspartate aminotransferase (AST; r = -0.076, P = 0.001), alanine aminotransferase (ALT; r = -0.079, P = 0.001), gamma-glutamyltransferase (r = -0.046, P = 0.046), and creatinine clearance (r = -0.113, P <0.001). A positive correlation was found between serum PSA and creatinine (r = 0.053, P = 0.024). Age did not correlate with serum PSA level. The influence of clinical parameters on serum PSA was explored using multiple linear regression analysis. Using the stepwise method, all other explanatory variables, except BMI, AST, and creatinine were eliminated (log10[PSA] = -0.124[BMI] + 0.063[creatinine] - 0.053[AST] + 0.097; r = 0.152, P <0.001).

CONCLUSIONS

BMI, creatinine, and AST may influence the serum PSA level in this population. However, because it was not clear that this group should be considered at high risk of prostate cancer in the future, additional longitudinal research is needed.

Effects of obesity and height on prostate-specific antigen (PSA) and percentage of free PSA levels among African-American and Caucasian men

BACKGROUND

Prior studies suggest that obese men have lower prostate-specific antigen (PSA) levels than leaner men. Caucasian (CA) men also may have lower PSA levels than African-American (AA) men, but the relevance of body size to racial disparities in PSA levels is unclear. The association between body mass index (BMI) and height on PSA and percentage of free PSA (%fPSA) was investigated within AA and CA men without a prior prostate cancer diagnosis.

METHODS

AA (n = 150) and CA (n = 149) men of similar socioeconomic status completed an extensive in-person interview and donated blood. PSA and %fPSA levels were compared across race, BMI, and height categories after adjusting for age and other factors.

RESULTS

PSA levels decreased with increasing BMI (PSA = .72, .69, .67, .59 ng/mL for BMI 18.5 to <25, 25 to <30, 30 to <35, and > or =35, respectively; P(trend) = .18), and trends were significant among men less than age 60 years (PSA = .81, .76, .66, .59, respectively; P(trend) = .02). fPSA also significantly decreased with BMI among men <60 years (P(trend) = .04). In contrast, %fPSA was not associated with BMI. However, %fPSA increased 27% across height categories (P(trend) = .02). PSA levels were significantly lower among CA men (PSA(AA) = 0.87, PSA(CA) = 0.63 ng/mL; P < .01), whereas %fPSA levels did not differ by race. Also, associations between body size and PSA or %fPSA did not significantly differ by race, and adjustment for BMI and height had no effect on the racial disparity in PSA (PSA(AA) = 0.87, PSA(CA) = 0.63 ng/mL; P < .01).

CONCLUSIONS

The data suggest that race, BMI, and height are independently associated with PSA and %fPSA levels.