Should prostate specific antigen be adjusted for body mass index? Data from the Baltimore Longitudinal Study of Aging

Body mass index in relation to prostate-specific antigen-related parameters

Background

Only a few previous studies conducted to assess the association between body mass index (BMI) and prostate-specific antigen (PSA) related parameters have taken prostate volume (PV) and blood volume (BV) into consideration. The objective of this study was to assess the relationship between BMI and parameters of PSA concentrations in Chinese adult men.

Methods

A total of 86,912 men who have received annual physical examination at the First Affiliated Hospital of Army Medical University from 1 January 2011 to 31 December 2018 were included in this study. Linear regression models were performed to assess the relationship between BMI, PV, BV and PSA, and analyze the correlation between BMI and PSA, PSA density and PSA mass.

Results

The univariable linear regression showed that PV, BV, systolic pressure (SBP), pulse, fasting blood glucose (FBG) and age were significantly associated with PSA level (P < 0.05). The multivariate linear regression demonstrated that PV, BV, FBG and age were significantly associated with PSA level (P < 0.05). WHR and BMI is negatively associated with PSA and PSA density (P < 0.05), and no statistically significant association was found between PSA mass and WHR and (P = 0.268) or BMI (P = 0.608).

Conclusions

The findings of this large-sample, hospital-based study in China indicate that PV was positively associated with serum PSA concentrations, while BMI and BV were inversely related with PSA levels. PSA mass can be used to estimate the PSA concentration without being affected by obesity in Chinese men.

Systematic review and meta-analysis of the associations between body mass index, prostate cancer, advanced prostate cancer, and prostate-specific antigen

PURPOSE

The relationship between body mass index (BMI) and prostate cancer remains unclear. However, there is an inverse association between BMI and prostate-specific antigen (PSA), used for prostate cancer screening. We conducted this review to estimate the associations between BMI and (1) prostate cancer, (2) advanced prostate cancer, and (3) PSA.

METHODS

We searched PubMed and Embase for studies until 02 October 2017 and obtained individual participant data from four studies. In total, 78 studies were identified for the association between BMI and prostate cancer, 21 for BMI and advanced prostate cancer, and 35 for BMI and PSA. We performed random-effects meta-analysis of linear associations of log-PSA and prostate cancer with BMI and, to examine potential non-linearity, of associations between categories of BMI and each outcome.

RESULTS

In the meta-analyses with continuous BMI, a 5 kg/m2 increase in BMI was associated with a percentage change in PSA of - 5.88% (95% CI - 6.87 to - 4.87). Using BMI categories, compared to normal weight men the PSA levels of overweight men were 3.43% lower (95% CI - 5.57 to - 1.23), and obese men were 12.9% lower (95% CI - 15.2 to - 10.7). Prostate cancer and advanced prostate cancer analyses showed little or no evidence associations.

CONCLUSION

There is little or no evidence of an association between BMI and risk of prostate cancer or advanced prostate cancer, and strong evidence of an inverse and non-linear association between BMI and PSA. The association between BMI and prostate cancer is likely biased if missed diagnoses are not considered.

Investigating the prostate specific antigen, body mass index and age relationship: is an age-BMI-adjusted PSA model clinically useful?

PURPOSE

Previous studies indicate a possible inverse relationship between prostate-specific antigen (PSA) and body mass index (BMI), and a positive relationship between PSA and age. We investigated the associations between age, BMI, PSA, and screen-detected prostate cancer to determine whether an age-BMI-adjusted PSA model would be clinically useful for detecting prostate cancer.

METHODS

Cross-sectional analysis nested within the UK ProtecT trial of treatments for localized cancer. Of 18,238 men aged 50-69 years, 9,457 men without screen-detected prostate cancer (controls) and 1,836 men with prostate cancer (cases) met inclusion criteria: no history of prostate cancer or diabetes; PSA < 10 ng/ml; BMI between 15 and 50 kg/m2. Multivariable linear regression models were used to investigate the relationship between log-PSA, age, and BMI in all men, controlling for prostate cancer status.

RESULTS

In the 11,293 included men, the median PSA was 1.2 ng/ml (IQR: 0.7-2.6); mean age 61.7 years (SD 4.9); and mean BMI 26.8 kg/m2 (SD 3.7). There were a 5.1% decrease in PSA per 5 kg/m2 increase in BMI (95% CI 3.4-6.8) and a 13.6% increase in PSA per 5-year increase in age (95% CI 12.0-15.1). Interaction tests showed no evidence for different associations between age, BMI, and PSA in men above and below 3.0 ng/ml (all p for interaction >0.2). The age-BMI-adjusted PSA model performed as well as an age-adjusted model based on National Institute for Health and Care Excellence (NICE) guidelines at detecting prostate cancer.

CONCLUSIONS

Age and BMI were associated with small changes in PSA. An age-BMI-adjusted PSA model is no more clinically useful for detecting prostate cancer than current NICE guidelines. Future studies looking at the effect of different variables on PSA, independent of their effect on prostate cancer, may improve the discrimination of PSA for prostate cancer.

Dilution effect of serum CA125 and CA19-9 over a cutoff value, according to obesity

The dilution effect of high plasma volume contributes to a lower level of specific tumor marker such as prostate-specific antigen. To date, few studies have focused on this effect of other tumor marker levels. Therefore, we evaluated the dilution effects of a higher plasma volume on lowering the serum concentration of various tumor markers such as CA125 and CA19-9. Data from patients (age ≥40 years) visiting our public health center between March 2007 and March 2013 were gathered. A total of 19,439 male and 11,655 female native Koreans were eligible to have a serum CA125 and CA19-9 screening for ovarian and pancreatic cancer, respectively. CA125 levels in 11,234 women were analyzed. There was a statistically significant trend toward a lower likelihood of having a serum CA125 level >35 U/mL with increased body mass index (BMI), with obese men having a 53.1% lower likelihood than those with a normal BMI. After CA19-9 analysis in 29,978 participants, there was also a significant trend toward a lower likelihood of having a serum CA19-9 level >35 U/mL with increased BMI, with obese men having a 27.0% and obese women having a 32.7% lower likelihood than those with a normal BMI. These results might affect tumor screening efficiency for ovarian and pancreatic cancer using serum CA125 and CA19-9, respectively. Further studies are needed to better define these results in clinical practice.

Association between obesity, prostate-specific antigen level and prostate-specific antigen density in men with a negative prostate biopsy

OBJECTIVE

To determine the association between body mass index (BMI), serum prostate-specific antigen (PSA) level and PSA density (PSAD) in patients with an elevated serum PSA level but a negative prostate biopsy.

METHODS

This retrospective study enrolled men with a negative prostate biopsy but a serum PSA level of 3.0-10 ng/ml. All men underwent anthropometric measurements, serum PSA determination and transrectal ultrasound examination. BMI was grouped according to the Asia-Pacific obesity criteria: nonobese (<25 kg/m(2)) versus obese (≥ 25 kg/m(2)). Partial correlation and linear regression models between PSA, PSAD and BMI were conducted after adjusting for age.

RESULTS

A total of 907 men were enrolled in this study. On multivariate analyses, PSA showed no significant correlation with age or BMI, whereas PSAD had a negative correlation with age and BMI. Similar results were obtained when patients were categorized as having low (3.0 < PSA  ≤ 6.5 ng/ml) or high PSA (6.5 < PSA ≤ 10.0 ng/ml) levels.

CONCLUSION

PSAD, but not PSA, demonstrated a significant negative correlation with BMI. This indicates that a new strategy including PSAD rather than simple PSA levels should be adopted in the study of obesity-adjusted PSA cut-offs.

The likelihood of having a serum PSA level of ≥2.5 or ≥4.0 ng ml(-1) according to obesity in a screened Korean population

This study aimed to determine if lower serum total prostate-specific antigen (PSA) levels in obese Korean men affect prostate cancer (PCa) screening, as an increased body mass index (BMI) is inversely associated with the PSA level. Between March 2007 and December 2012, 22 208 native Korean men who were eligible to receive a serum PSA test were recruited. Logistic regression was used to estimate the odds of an 'abnormal' PSA (≥2.5 or ≥4.0 ng ml(-1)) in these men (age: 45-75 years, PSA <10 ng ml(-1)) based on BMI, which was categorized as normal (BMI <25 kg m(-2)) and obese (BMI ≥25 kg m(-2)). In all, 20 509 men (92.3%) were included in the study after applying the inclusion criteria. After controlling for age, there was a statistically significant trend towards a lower likelihood of having a serum PSA level ≥2.5 ng ml(-1) with an increased BMI, with obese men having an 18% lower likelihood (odds ratio: 0.823, 95% confidence interval: 0.743-0.912; P<0.001) compared to men with a normal BMI. Obese men were approximately 82% as likely to have a PSA level ≥2.5 ng ml(-1) as men with a normal BMI. These results might affect PCa screening using serum total PSA. Further studies are needed to better define these results in clinical biopsy practice.

Opium consumption is negatively associated with serum prostate-specific antigen (PSA), free PSA, and percentage of free PSA levels

Addiction to opium continues to be a major worldwide medical and social problem. The study addressing the association between opium consumption and serum prostate-specific antigen (PSA) level is lacking. We determined the effects of opium consumption on serum PSA levels in opium-addict men. Our study subjects comprised 438 opium-addict men with a mean age of 52.2 ± 6.4 years (group 1). We compared these men with 446 men who did not indicate current or past opium use (group 2). Serum total PSA (tPSA), free PSA (fPSA), % fPSA, and sex hormones were compared between the 2 groups. The mean serum tPSA level was significantly lower in group 1 (1.05 ng/mL) than in controls (1.45 ng/mL) (P = 0.001). Opium consumption was also associated with lower fPSA (P = 0.001) and % fPSA (P = 0.001). Serum free testosterone level in opium-addict patients (132.5 ± 42 pg/mL) was significantly lower than that in controls (156.2 ± 43 pg/mL) (P = 0.03). However, no significant correlation existed between tPSA and free testosterone levels (r = 0.28, 95% CI, -0.036 to 0.51, P = 0.34). Among the patients with cancer in group 1, 35% were found to have high-grade tumor (Gleason score ≥ 7) compared with 26.7% in group 2 (P = 0.02). Total PSA and fPSA were strongly correlated with duration of opium use (r = -0.06, 95% CI, -0.04 to -0.08, P = 0.0001; and r = -0.05, 95% CI, -0.03 to -0.07, P = 0.0001, respectively). Opium consumption is independently and negatively associated with serum tPSA, fPSA, and % fPSA levels.

Effects of EPA, γ-linolenic acid or coenzyme Q10 on serum prostate-specific antigen levels: a randomised, double-blind trial

The main objective of the present study was to determine the potential of n-3 and n-6 fatty acids or coenzyme Q10 (CoQ10) to alter serum prostate-specific antigen (PSA) levels in normal healthy men. A total of 504 healthy men with serum PSA level ≤ 2·5 ng/ml were recruited into the study. Serum PSA values were not segregated by decade of age. Participants were randomly assigned to a daily dietary supplement containing n-3 fatty acids (1·12 g of EPA and 0·72 g of DHA per capsule) (group 1, n 126), n-6 fatty acid (600 mg γ-linolenic acid (GLA) each capsule) (group 2, n 126), CoQ10 (100 mg per capsule) (group 3, n 126) or a similar regimen of placebo (group 4, n 126) for 12 weeks. Study medication was administered as two capsules to be taken twice daily. Serum levels of PSA, EPA, DHA, GLA, lipid profile and reproductive hormones were also measured. EPA treatment significantly reduced serum PSA level by 30·0 (95 % CI 25, 36) % (P= 0·004) from baseline. In contrast, GLA therapy significantly increased serum PSA concentration by 15·0 (95 % CI 11, 20) % (P= 0·02). CoQ10 therapy also significantly reduced serum PSA level by 33·0 (95 % CI 27, 40) % (P= 0·002). In multivariable analysis, serum values of PSA were strongly correlated with duration of EPA (r - 0·62; 95 % CI - 0·42, - 0·77; P= 0·003), n-6 (r 0·42; 95 % CI 0·31, 0·58; P= 0·02) and CoQ10 use (r - 0·77; 95 % CI - 0·56, - 0·87; P= 0·001). There were also significant correlations between serum values of DHA, EPA, GLA and CoQ10 and serum PSA levels. The present study demonstrates that dietary supplements containing EPA, GLA or CoQ10 may significantly affect serum PSA levels.

The impact of obesity on the predictive accuracy of PSA in men undergoing prostate biopsy

PURPOSE

Obese men have been reported to have lower serum PSA values relative to normal-weight men in population-based studies, screening cohorts, and in men with prostate cancer (CaP) treated with surgery. There are concerns that PSA may be less accurate in detecting prostate cancer in men with increased body mass index (BMI). We determine whether the diagnostic potential of PSA is negatively influenced by obesity by comparing its operating characteristics across BMI categories among men undergoing prostate biopsy.

METHODS

Demographic, clinical, and histopathological data on 917 men who underwent trans-rectal ultrasound-guided prostate needle biopsy from 2002 to 2010 at a University hospital in Italy were used in the study. Men were categorized for BMI as follows: <25 kg/m(2) (normal weight), 25-29.9 kg/m(2) (overweight), and ≥ 30 kg/m(2) (obese). Receiver operator characteristics (ROC) curves were used to assess PSA accuracy for predicting prostate cancer overall and then stratified according to digital rectal examination (DRE) findings using the area under the ROC curve (AUC).

RESULTS

The obesity rate of the study cohort was 21 %. There was no statistically significant difference in the overall AUCs of PSA for predicting CaP among normal-weight (AUC = 0.56), overweight (AUC = 0.60), and obese men (AUC = 0.60; p = 0.68) in either DRE-positive or negative men.

CONCLUSIONS

In a cohort of Italian men undergoing prostate biopsy, the performance accuracy of PSA as a predictor of CaP is not significantly altered by BMI. Obesity does not negatively impact the overall ability of PSA to discriminate between CaP and benign conditions.

Which obesity index best correlates with prostate volume, prostate-specific antigen, and lower urinary tract symptoms?

OBJECTIVE

To determine which measurement variable, waist circumference (WC), body mass index (BMI), or waist-to-hip ratio (WHR) is most closely related to the prostate volume (PV), prostate-specific antigen (PSA), and lower urinary tract symptoms (LUTS).

METHODS

Between January 2010 and September 2011, 1632 consecutive ostensibly healthy Korean men aged 40-69 years who visited our clinic for a prostate checkup were enrolled into the study. Exclusion criteria included pyuria, history of lower urinary tract disorder influencing urination, and a high PSA level of >3.0 ng/mL. All men underwent a detailed clinical evaluation using the International Prostate Symptom Score (I-PSS) questionnaire. Anthropometric measurements were determined. Serum PSA, urinalysis, and transrectal ultrasound were also performed.

RESULTS

Data from 1601 men were analyzed. The mean age was 51.6 years, WC 83.7 cm, BMI 24.8 kg/m(2), PV 24.6 mL, and the mean PSA level was 1.07 ng/mL. Using multivariate analysis, PV most positively associated with WC (P < .001), while PSA level had negatively associated with BMI (P = .036) and no significant association with WC or WHR was noted. There was no significant relationship between various obesity indexes and I-PSS.

CONCLUSION

Our data showed that PV positively associated with central obesity, as represented by WC. In contrast, serum PSA negatively associated with BMI, which represented overall obesity (ie, hemodilution). Our data also suggested that obesity is not associated with lower urinary tract symptoms in Korean men.

[Effect of body mass index on PSA in northeast Mexican patients]

OBJECTIVE

To evaluate the effect of body mass index (BMI) on PSA in northeast Mexican patients included in prostate cancer (Pca) early detection screening campaigns offered by our institution.

MATERIAL AND METHODS

One hundred and ninety seven patients came voluntarily to our Pca early detection screening campaigns.

EXCLUSION CRITERIA

PSA >10 ng/dl, patients on 5-α Reductase inhibitors or hormonal replacement. Overweight and obesity were considered when BMI was between 25-29.9 and ≥30 kg/m(2) respectively. Simple linear and multiple regression were used in the statistical analysis. Mean and standard deviation were utilized to evaluate spread and normal distribution. P values <0.05 were considered statistically significant.

RESULTS

One hundred and fifty two patients were included in this study. Forty four percent (83) and 30.3%(46) presented with overweight and obesity, respectively. Mean BMI was 28.16 kg/m(2) (SD 1.77). A statistically significant negative effect of BMI on PSA was observed in the linear regression. This effect persisted when adjusted for age in the multiple regression model. A decrease of 0.085 ng/dl for every unit of BMI (p <0.001) was observed in the simple linear regression. This value was 0.07 in the multiple regression (p=0.006) CONCLUSIONS: A higher negative effect of BMI on PSA was found in comparison to published literature. A higher proportion of patients with BMI >25 kg/m(2) than the national mean was observed. A multicentric national study is needed in order to challenge these results.

The effect of demographic and clinical factors on the relationship between BMI and PSA levels

INTRODUCTION

Studies have reported lower prostate specific antigen (PSA) levels in men with a higher body mass index (BMI). Additional factors such as diabetes mellitus, benign prostatic hyperplasia (BPH) and certain medications may also affect PSA levels and confound the PSA-BMI association. In this study we evaluated the potential confounding effect of these factors on the obesity-PSA relationship and evaluated the association between these factors and PSA level.

METHODS

The study cohort consisted of 770 population-based controls without a history of prostate cancer (PCa) who participated in a prior PCa study. Demographic, anthropometric, and medical history data were obtained, and PSA level was determined from blood drawn at the time of interview. Linear regression was performed to evaluate the PSA-BMI relationship, adjusting for potential confounders. Finally, a forward stepwise algorithm was used to determine which factors were independently associated with PSA values.

RESULTS

With increase in BMI (<25, 25-29, ≥30), the geometric mean PSA level declined (1.18, 1.13, and 0.94, respectively); obese men had a 17% (95% CI 0.70-0.99) lower age-adjusted PSA level compared to normal weight men. However, this relationship was non-significant (P = 0.17) in the multivariate model. Independent predictors of PSA level included age (β = 1.03, 95% CI 1.02-1.04), history of BPH (β = 1.48, 95% CI 1.27-1.72), current statin (β = 0.85, 95% CI 0.74-0.98), and NSAID use (β = 0.84, 95% CI 0.72-0.98).

CONCLUSION

The relationship between obesity and PSA is confounded by a number of factors, which likely explain the observed inverse association previously reported. These results should help in interpreting PSA values in men screened for PCa.

Impact of body mass index on outcomes after conformal radiotherapy in patients with prostate cancer

PURPOSE

Several retrospective analyses have suggested that obese men with prostate cancer treated with external beam radiotherapy (EBRT) have outcomes inferior to those of normal-weight men. However, a recently presented analysis for the first time challenged this association between body mass index (BMI) and treatment failure. It is therefore important to provide further data on this issue.

METHODS AND MATERIALS

This was a retrospective analysis of 564 men treated with risk-adapted conformal EBRT at a single institution. Low-risk patients received EBRT alone, and the other patients received EBRT plus endocrine treatment. In addition, high-risk patients were treated to higher EBRT doses (74 Gy). A rectal balloon catheter for internal immobilization, which can be identified on portal images, was used in 261 patients (46%). Thus, localization did not rely on bony landmarks alone in these cases.

RESULTS

The median BMI was 26, and 15% of patients had BMI≥30. Neither univariate nor multivariate analyses detected any significant impact of BMI on biochemical relapse, prostate cancer-specific survival, or overall survival. The 5-year biochemical relapse rate was 21% and prostate cancer-specific survival 96%.

CONCLUSIONS

The present analysis of a large cohort of consecutively treated patients suggests that efforts to reduce prostate movement and geographic miss might result in comparable outcomes in obese and normal-weight patients.