Insulin-like growth factor-1, insulin-like growth factor binding protein-3, and body mass index: clinical correlates of prostate volume among Black men

Association between metabolic syndrome and benign prostatic hyperplasia: The underlying molecular connection

Benign prostatic hyperplasia (BPH), a common cause of lower urinary tract symptoms (LUTS), has been recently regarded as a metabolic disease. Metabolic syndrome (MetS) is a constellation of metabolic disarrangements, including insulin resistance, obesity, hypertension, and dyslipidemia, and it has been established that these components of MetS are important contributing factors exacerbating the degree of prostatic enlargement and bladder outlet obstruction among patients with BPH. Clinical and experimental studies demonstrated that many molecules, such as insulin, insulin-like growth factor 1 (IGF-1), androgen and estrogen, and adipokines, are involved in the overlapping pathogenesis of BPH and MetS, indicating that clinicians might be able to simultaneously alleviate or cure two diseases by choosing appropriate medications. This article aims to systematically review the pathophysiological aspect and traditional etiology and pathogenesis of BPH and discuss the intricate association between MetS and BPH from the molecular point of view, in an attempt to provide stronger evidence for better treatment of two diseases.

Modified bladder outlet obstruction index for powerful efficacy prediction of transurethral resection of prostate with benign prostatic hyperplasia

Background

The correlation between modified bladder outlet obstruction index (MBOOI) and surgical efficacy still remains unknown. The purpose of the study was to investigate the clinical value of the MBOOI and its use in predicting surgical efficacy in men receiving transurethral resection of the prostate (TURP).

Methods

A total of 403 patients with benign prostate hyperplasia (BPH) were included in this study. The International Prostate Symptom Score (IPSS), quality of life (QoL) index, transrectal ultrasonography, and pressure flow study were conducted for all patients. The bladder outlet obstruction index (BOOI) (P_detQ_max–2Q_max) and MBOOI (P_ves–2Q_max) were calculated. All patients underwent TURP, and surgical efficacy was accessed by the improvements in IPSS, QoL, and Q_max 6 months after surgery. The association between surgical efficacy and baseline factors was statistically analyzed.

Results

A comparison of effective and ineffective groups based on the overall efficacy showed that significant differences were observed in PSA, P_ves, P_detQ_max, P_abd, BOOI, MBOOI, TZV, TZI, IPSS-t, IPSS-v, IPSS-s, Q_max, and PVR at baseline (p < 0.05). Binary logistic regression analysis suggested that MBOOI was the only baseline parameter correlated with the improvements in IPSS, QoL, Q_max, and the overall efficacy. Additionally, the ROC analysis further verified that MBOOI was more optimal than BOOI, TZV and TZI in predicting the surgical efficacy.

Conclusion

Although both MBOOI and BOOI can predict the clinical symptoms and surgical efficacy of BPH patients to a certain extent, however, compared to BOOI, MBOOI may be a more useful factor that can be used to predict the surgical efficacy of TURP.

Trial registration retrospectively registered.

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.

Body size throughout the life-course and incident benign prostatic hyperplasia-related outcomes and nocturia

BACKGROUND

Existing evidence suggests that there is an association between body size and prevalent Benign Prostatic Hyperplasia (BPH)-related outcomes and nocturia. However, there is limited evidence on the association between body size throughout the life-course and incident BPH-related outcomes.

METHODS

Our study population consisted of men without histories of prostate cancer, BPH-related outcomes, or nocturia in the intervention arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) (n = 4710). Associations for body size in early- (age 20), mid- (age 50) and late-life (age ≥ 55, mean age 60.7 years) and weight change with incident BPH-related outcomes (including self-reported nocturia and physician diagnosis of BPH, digital rectal examination-estimated prostate volume ≥ 30 cc, and prostate-specific antigen [PSA] concentration > 1.4 ng/mL) were examined using Poisson regression with robust variance estimation.

RESULTS

Men who were obese in late-life were 25% more likely to report nocturia (Relative Risk (RR): 1.25, 95% Confidence Interval (CI): 1.11-1.40; p-trend_{for continuous BMI} < 0.0001) and men who were either overweight or obese in late-life were more likely to report a prostate volume ≥ 30 cc (RR_overweight: 1.13, 95% CI 1.07-1.21; RR_obese: 1.10, 95% CI 1.02-1.19; p-trend_{for continuous BMI} = 0.017) as compared to normal weight men. Obesity at ages 20 and 50 was similarly associated with both nocturia and prostate volume ≥ 30 cc. Considering trajectories of body size, men who were normal weight at age 20 and became overweight or obese by later-life had increased risks of nocturia (RR_{normal to overweight}: 1.09, 95% CI 0.98-1.22; RR_{normal to obese}: 1.28, 95% CI 1.10-1.47) and a prostate volume ≥ 30 cc (RR_{normal to overweight}: 1.12, 95% CI 1.05-1.20). Too few men were obese early in life to examine the independent effect of early-life body size. Later-life body size modified the association between physical activity and nocturia.

CONCLUSIONS

We found that later-life body size, independent of early-life body size, was associated with adverse BPH outcomes, suggesting that interventions to reduce body size even late in life can potentially reduce the burden of BPH-related outcomes and nocturia.

African Immigrant Health: Prostate Cancer Attitudes, Perceptions, and Barriers

Prostate cancer (PCa) is the second leading cause of cancer-related death among Black men who present with higher incidence, mortality, and survival compared to other racial groups. African immigrant men, however, are underrepresented in PCa research and thus this research sought to address that gap. This study applied a social determinants of health framework to understand the knowledge, perceptions, and behavioral tendencies regarding PCa in African immigrants. African immigrant men and women residing in different parts of the country (California, Texas, Colorado, Oklahoma, and Florida) from various faith-based organizations, African community groups, and social groups were recruited to participate in key informant interviews (n = 10) and two focus groups (n = 23). Four themes were identified in this study: (a) PCa knowledge and attitudes-while knowledge is very limited, perceptions about prostate health are very strong; (b) culture and gender identity strongly influence African health beliefs; (c) preservation of manhood; and (d) psychosocial stressors (e.g., financial, racial, immigration, lack of community, and negative perceptions of invasiveness of screening) are factors that play a major role in the overall health of African immigrant men. The results of this qualitative study unveiled perceptions, attitudes, beliefs, and knowledge of PCa among African immigrants that should inform the planning, development, and implementation of preventive programs to promote men's health and PCa awareness.

Analysis of risk factors for post-bacillus Calmette-Guerin-induced prostatitis in patients with non-muscle invasive bladder cancer

The objective of this study was to evaluate risk factors for bacillus Calmette–Guerin-induced prostatitis in patients with non-muscle invasive bladder cancer following bacillus Calmette–Guerin therapy. Clinical findings from patients with non-muscle invasive bladder cancer who underwent multi-parametric magnetic resonance imaging before transurethral resection of bladder tumor and post-bacillus Calmette–Guerin therapy from March 2004 to August 2018 were evaluated. The population was grouped into patients with or without newly developed lesions on multi-parametric magnetic resonance imaging performed 3 months after bacillus Calmette–Guerin instillation. Patients with prostate-specific antigen levels ≥ 4 ng/mL or prostate cancer were excluded. Univariable and multivariable analyses were performed to determine the predictors of prostate lesions in patients with prior bacillus Calmette–Guerin exposure. Post bacillus Calmette–Guerin-induced prostatitis was found in 50 of the 194 patients (25.8%). No significant differences were observed between the groups except for prostate volumes (33.8 mL vs. 30.8 mL, P = 0.012) and body mass index (25.2 kg/m² vs. 24.1 kg/m², P = 0.044). After bacillus Calmette–Guerin exposure, no significant differences in prostate-specific antigen levels, international prostate symptom scores, or post-voiding residual volume were noted. Multivariable regression analysis showed that body mass index (odds ratio, OR = 1.115, P = 0.038) and prostate volume (OR = 3.080, P = 0.012) were significant predictors of post-bacillus Calmette–Guerin prostate lesions. Body mass index and prostate volume may be clinical predictors of prostate lesions after bacillus Calmette–Guerin exposure. Awareness of potential risk factors for this entity should contribute to the clinical decision-making process for patients following bacillus Calmette–Guerin therapy.

Comparison of prostate size and anthropometric parameters between diabetic and non-diabetic Congolese patients who underwent transurethral prostate resection in the Democratic Republic of Congo

Background

Benign prostate hyperplasia (BPH) and type 2 diabetes mellitus are prevalent in older men, and both represent a challenge to public health. Prior studies reported a correlation between BPH and (hyper)glycaemia, a component of the metabolic syndrome, which is on the increase in sub-Saharan Africa (SSA) due to rapid modernization. This study was designed to evaluate the association of prostate volume and anthropometric parameters among diabetic and non-diabetic patients who had transurethral resection of the prostate (TURP) for BPH.

Results

We analyzed data of 159 selected patients who had TURP over a three-year period (February 2014–January 2017) for histologically confirmed BPH. Mean age in the entire cohort was 68 ± 8.5 years. Out of the 159 patients, 94 (59.1%) were non-diabetics and 65 (40.9%) were diabetics. International Prostate Symptom Score (IPSS) and fasting blood glucose were significantly higher in diabetic than in non-diabetic group (28.6 ± 4.3 vs 25.6 ± 6.4, and p 0.005; 121.7 ± 45.7 vs 85.4 ± 11.7 mg/dl, and p < 0.001, respectively). BMI and waist circumference were statistically greater in non-diabetics than in diabetics (25.1 ± 3.3 kg/m2 vs 23.6 ± 3.5 kg/m2, and p 0.008; 94.6 cm ± 10.3 vs 90.6 ± 10.4 cm, and p 0.018). Diabetic patients had larger prostate volume than non-diabetic in the working age subgroup only (< 65 years of age); beyond 65 years, this difference was not consistent (62.6 ± 23.1 cc vs 50.1 ± 20.7 cc, and p 0.027; 56.2 ± 23.7 cc vs 49 ± 20.2 cc, and p 0.15, respectively). Prostate size was significantly associated with fasting blood glucose (p = 0.002) and PSA (p = 0.027). However, prostate size was not related to age, presence of diabetes, BMI, waist circumference, IPSS, quality of life score, and duration of symptoms.

Conclusion

Prostate volume is not correlated with anthropometric parameters in diabetic and non-diabetic Congolese patients who had TURP in South Kivu. Diabetics were not obese and yet had larger prostate volume than non-diabetics < 65 years of age. It is hoped that these results would form groundwork for further studies on this topic in SSA region.

Impact of metabolic syndrome-related factors on the development of benign prostatic hyperplasia and lower urinary tract symptoms in Asian population

This study aimed to investigate the metabolic syndrome-related risk factors for the development of benign prostatic hyperplasia (BPH) with lower urinary tract symptoms (LUTS) in healthy men.A total of 4880 healthy men who underwent transrectal ultrasonography at our hospital during routine health examinations were included in this study. Those who had undergone a prior biopsy or surgery for prostate disease, were suspected of having urinary tract infection, or were taking BPH/LUTS or metabolic syndrome medications were excluded. BPH/LUTS was defined as an International Prostate Symptom Score (IPSS) of ≥8 and a prostate volume (PV) of ≥30 cm.The subjects had a mean age of 54.1 years, PV of 29.2 cm, prostate-specific antigen (PSA) level of 1.20 ng/mL, and IPSS of 9.2. The annual PV growth rate was 0.48 cm/year. Age, body mass index (BMI), PSA, basal metabolic rate, apolipoprotein A-1, fasting blood glucose, high-density lipoprotein (HDL) cholesterol levels were significant predictive factors for PV. Age, PSA, apolipoprotein B, fasting blood glucose, cholesterol, HDL, and low-density lipoprotein (LDL) levels were predictors of BPH/LUTS at the initial health examination. A decreased fat mass and LDL level were a significant risk factor for the development of BPH/LUTS within 5 years in men without a BPH/LUTS diagnosis at the initial examination.Metabolic syndrome-related variables were strongly associated with BPH/LUTS and by decreasing fat mass and LDL levels, development of BPH/LUTS could be prevented within 5 years in healthy Korean men.

Visceral adiposity index is associated with benign prostatic enlargement in non-diabetic patients: a cross-sectional study

OBJECTIVE

To evaluate the association between visceral adiposity index (VAI) - a novel indicator for the assessment of visceral adipose tissue and prostate enlargement in non diabetic patients.

MATERIAL AND METHODS

Four hundred patients who were admitted to the Urology clinic between January and December 2014 with complaints of BPH(benign prostatic hyperplasia )/LUTS(male lower urinary tract symptoms)were enrolled in this cross-sectional study. Patients were divided into two groups according to their prostate volume and international prostate symptom score (IPSS) value. They were compared in terms of age, body mass index (BMI), VAI, prostate volume, PSA, post micturional residual volume (PMRV), uroflowmetry Q max value, triglyceride (TG), high density lipoprotein-cholesterol (HDL-C) and fasting blood sugar (FBS).

RESULTS

Although univariate analyses reveal that age, BMI, waist circumference (WC), FBS, TG, HDL-C level and TG/HDL ratio were correlated with prostate volume, only age [1.125 OR (1.088-1.164), p = .00001], BMI [1.119 OR (1.040-1.204), p = .003], TG [1.043 OR (1.016-1.071), p = .002], HDL-C [0.923 OR (0.860-0.990), p = .025] and VAI [1.194 OR (1.110-1.305), p = .011] were statistically significant in multivariate analysis. A positive correlation was found between VAI value and prostate volume in the Spearman correlation test (r = 0.29, p = .00001). The calculated area under the curve (AUC) for prostate volumes of 30, 40 and 50 ml were 0.680 (0.621-0.738), 0.625 (0.570-0.681) and 0.590 (0.528-0.652), respectively.

CONCLUSION

Our study revealed a positive correlation between VAI and prostate volume. Our results are needed to be tested with well-designed randomized prospective cohort studies.

Obesity inversely correlates with prostate-specific antigen levels in a population with normal screening results of prostate cancer in northwestern China

Serum prostate-specific antigen (PSA) is a diagnostic biomarker of prostate cancer and is possibly associated with obesity. This study aimed to explore the relationships between obesity indicators [body mass index (BMI) and waist circumference (WC)] with PSA in Chinese men. A cross-sectional study of men aged 30-85 years undergoing prostate cancer screening was conducted from August 2008 to July 2013 in Xi'an, China. Data were obtained from clinical reports, condition was recorded based on self-report including demographics, weight, height, and WC (>90 cm=obese). Fasting blood glucose (FBG) and prostate volume (PV) were assessed clinically. Patients were grouped by BMI (normal=22.9, overweight=23-27.4, obese≥27.5 kg/m²). PSA parameters of density (PSAD), PSA serum level, and PSA increasing rate per year (PSAR) were calculated per BMI and age groups (30-40, 41-59, 60-85 years). Obesity indicators (BMI and WC) and PSA parameter relationships were modeled by age-stratified linear regression. Of 35,632 Chinese men surveyed, 13,084 were analyzed, including 13.44% obese, 57.44% overweight, and 29.12% normal weight, according to BMI; 25.84% were centrally (abdominally) obese according to WC. BMI and WC were negatively associated with all PSA parameters, except PSAD and PSAR [P<0.05, BMI: β=-0.081 (95%CI=-0.055 to -0.036), WC: β=-0.101 (-0.021 to -0.015)], and independent of FBG and PV (P<0.05) in an age-adjusted model. In conclusion, obesity was associated with lower PSA in Chinese men. Therefore, an individual's BMI and WC should be considered when PSA is used to screen for prostate cancer.

Benign prostatic hyperplasia, metabolic syndrome and androgenic alopecia: Is there a possible relationship?

OBJECTIVE

To evaluate the incidence of benign prostatic hyperplasia (BPH) and metabolic syndrome in patients with androgenetic alopecia (AGA) in comparison with those with no AGA, as several previous studies have reported inconsistent results of an association between metabolic syndrome and BPH with AGA.

PATIENTS SUBJECTS AND METHODS

This cross-sectional study included 400 participants, divided into 300 patients diagnosed with AGA, with different grades according to Norwood-Hamilton classification, and 100 control subjects with no AGA. Criteria for diagnosis of metabolic syndrome according to Adult Treatment Panel-III criteria (waist circumference, blood pressure, fasting blood sugar, high-density lipoprotein and triglycerides), as well as criteria for diagnosis of BPH (prostatic volume, urine flow, and prostate-specific antigen) were assessed in all patients and compared with the control subjects.

RESULTS

There were significant differences between the AGA and no-AGA groups for the following variables: waist circumference, body mass index, fibrinogen level, fasting blood sugar, cholesterol, C-reactive protein, erythrocyte sedimentation rate, and glycosylated haemoglobin. There was a significant difference in number of patients with AGA manifesting criteria of metabolic syndrome (51% vs 28%), as well as BPH diagnostic criteria (36% vs 6.8%) compared with the control subjects. Both BPH and metabolic syndrome were shown to be significant independent variables associated with AGA.

CONCLUSIONS

Dermatologists, urologists, and primary care physicians should monitor patients with early onset AGA for the development of urinary symptoms, to permit an earlier diagnosis of BPH; and for metabolic syndrome symptoms, to permit early diagnosis of cardiovascular risk factors.

Metformin association with lower prostate cancer recurrence in type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

Accumulating evidence suggests that metformin possesses anticarcinogenic properties, and its use is associated with favorable outcomes in several cancers. However, it remains unclear whether metformin influences prognosis in prostate cancer (PCa) with concurrent type 2 diabetes (T2D).

MATERIALS AND METHODS

We searched PubMed, EMBASE, and the Cochrane Library from database inception to April 16, 2014 without language restrictions to identify studies investigating the effect of metformin treatment on outcomes of PCa with concurrent T2D. We conducted a meta-analysis to quantify the risk of recurrence, progression, cancer-specific mortality, and all-cause mortality. Summary relative risks (RRs) with corresponding 95% confidence intervals (CIs) were calculated. Publication bias was assessed by Begg's rank correlation test.

RESULTS

A total of eight studies fulfilled the eligibility criteria. We found that diabetic PCa patients who did not use metformin were at increased risk of cancer recurrence (RR, 1.20; 95%CI, 1.00-1.44), compared with those who used metformin. A similar trend was observed for other outcomes, but their relationships did not reach statistical significance. Funnel plot asymmetry was not observed among studies reporting recurrence (p=0.086).

CONCLUSIONS

Our results suggest that metformin may improve outcomes in PCa patients with concurrent T2D. Well-designed large studies and collaborative basic research are warranted.

Preoperative erectile function and the pathologic features of prostate cancer

Purpose

We evaluated whether preoperative erectile function is associated with pathologic features in the patients who underwent radical prostatectomy (RP).

Materials and Methods

We reviewed medical records of 1,743 men who underwent RP from November 2003 through May 2012. Of these, 50 patients who had prior hormone therapy and 272 patients who had lacking data of International Index of Erectile Function-5 (IIEF-5) were excluded. Men whose IIEF-5 was in the lower 25 percentile were assigned as Low Erectile Function group and the others were assigned as Control group. We compared pathologic features using univariable and multivariable logistic regression analysis between two groups.

Results

A total of 1,421 patients were included in the analysis. Patients’ age was 65.8 ± 6.7 years and prostate-specific antigen (PSA) was 12.8±16.1 ng/mL. Median and low 25 percentile of IIEF-5 were 14 and 8, respectively. Low Erectile Function group (IIEF-5<8) had higher risk to have high Gleason score (≥7(4+3), odds ratio (OR) 1.642, p<0.001) and large tumor volume (≥5 mL, OR 1.292, p=0.042). Even after adjusting age, year of surgery, body mass index, Charlson comorbidity index, PSA, clinical stage and biopsy Gleason score, Low Erectile Function group still had higher risk of high Gleason score (OR 1.910, p<0.001) and large tumor volume (OR 1.390, p=0.04) by multivariable logistic regressions.

Conclusions

Lower erectile function before RP was associated with higher Gleason’s score and larger tumor volume in final pathology. Thus, erectile function could be a surrogate barometer for prostate cancer aggressiveness.

Establishment of Reference Ranges for Prostate Volume and Annual Prostate Volume Change Rate in Korean Adult Men: Analyses of a Nationwide Screening Population

We aimed to determine normal reference ranges for prostate volume (PV) and annual PV change rate in a Korean nationwide screening population. Data from men who underwent a routine health check-up were collected from 13 university hospitals. The cohort comprised men aged ≥40 yr who had undergone 2 or more serial transrectal ultrasonographies. Men with initial PV>100 mL; serum PSA level>10 ng/mL; PV reduction>20% compared with initial PV, or who had history of prostate cancer or prostate surgery, were excluded. Linear regression and mixed effects regression analyses were used to predict mean PV and longitudinal change in PV over time. A total of 2,967 men formed the study cohort. Age, body mass index (BMI), and serum prostate-specific antigen (PSA) level were found to be significant predictors of PV. A predicted PV table, with a 95% confidence interval (CIs), was developed after adjusting for these 3 variables. Annual PV change rate was 0.51 mL/year (95% CI, 0.47-0.55). Annual PV change rate according to age was 0.68 mL/year, 0.84 mL/year, 1.09 mL/year, and 0.50 mL/year for subjects in their 40s, 50s, 60s, and ≥70 yr, respectively. Predicted annual PV change rate differed depending on age, BMI, serum PSA level and baseline PV. From a nationwide screening database, we established age-, PSA-, and BMI-specific reference ranges for PV and annual PV change rate in Korean men. Our newly established reference ranges for PV and annual PV change rate will be valuable in interpreting PV data in Korean men.

Linking pre-diabetes with benign prostate hyperplasia. IGFBP-3: a conductor of benign prostate hyperplasia development orchestra?

Benign prostatic hyperplasia (BPH) represents a pattern of non-malignant growth of prostatic fibromuscular stroma. Metabolic disturbances such us pre-diabetes and metabolic syndrome may have a role in BPH pathophysiology. A potential explanation for the above relationship involves the insulin-like growth factor (IGF) axis as well as IGF binding proteins, (IGFBPs) of which the most abundant form is IGFBP-3. Therefore, the aim of the present study was to investigate the association between intra-prostatic levels of IGF-1, IGF-2 as well as to evaluate the role of locally expressed IGFBP-3 in BPH development in pre-diabetes. A total of 49 patients admitted to the Urology department of a tertiary urban Greek hospital, for transurethral prostate resection, or prostatectomy and with pre-diabetes [impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) or both] were finally included. The majority of the sample consisted of subjects with IGT (51.0%), followed by IFG and IGT (32.7%) and isolated IFG (16.3%). For all participants a clinical examination was performed and blood samples were collected. In addition, total prostate (TP) volume or transitional zone (TZ) volume were estimated by transrectal ultrasonography. The results of the multivariate analysis regarding TP volume showed that higher PSA (p<0.001), larger waist circumference (p=0.007) and higher IGFBP-3 expression levels (p<0.001) independently predicted higher TP volume. The results regarding the volume of the TZ showed that higher PSA (p<0.001), larger waist circumference (p<0.001) and higher IGFBP-3 expression levels (p=0.024) were independently associated with higher TZ volume. Our findings show that intra-prostatic levels of IGFBP-3, PSA and waist circumference, but not overall obesity, are positively associated with prostate volume. IGFBP-3 seems to be a multifunctional protein, which can potentiate or inhibit IGF activity.

Hyperglycemia, hyperinsulinemia, insulin resistance, and the risk of BPH/LUTS severity and progression over time in community dwelling black men: the Flint Men's Health Study

OBJECTIVE

To examine the associations between fasting serum glucose, insulin concentrations, and insulin resistance and benign prostatic hyperplasia (BPH) in a population-based cohort of African American men.

METHODS

Using the Flint Men's Health Study (FMHS), we examined how fasting serum glucose and insulin concentrations and calculated Homeostasis Model of Assessment-Insulin Resistance (HOMA-IR) related to burden and progression of clinical markers of BPH in African American men aged 40-79 years.

RESULTS

Among 369 men at baseline, mean age was 56.6 years and approximately 70% were overweight/obese (body mass index [BMI] ≥25 kg/m(2)). One hundred forty-eight men (34.4%) reported moderate to severe lower urinary tract symptoms (LUTS) (American Urological Association Symptom Index [AUASI] ≥8). There were no significant trends of metabolic disturbances as measured by serum glucose, insulin, or HOMA-IR in men with indications of BPH compared to those without.

CONCLUSION

In this population-based study of African American men aged 40-79 years, we did not observe any significant associations between hyperglycemia, hyperinsulinemia, and insulin resistance and burden and progression of BPH after adjustment for age and BMI. This may be due, in part, to the single measurement of glucose and insulin, which may not adequately reflect average glucose metabolism. Further studies examining measures of long-term glycemic control and BPH in racially diverse populations are warranted.

Influence and pathophysiological mechanisms of simvastatin on prostatic hyperplasia in spontaneously hypertensive rats

OBJECTIVE

To explore the effects and mechanisms of simvastatin on prostate hyperplasia in spontaneously hypertensive rats (SHRs).

METHODS

Thirty-six male SHRs were randomly divided into three groups: the 10 and the 20 mg/kg/d simvastatin group and the control group. After 6 weeks the ultra-microscopic prostate structures were observed. The serum levels of interleukin-6 (IL-6), insulin-like growth factor (IGF-1) and angiotensin II (Ang-II) were measured by enzyme-linked immunosorbent assays. The endothelium-derived nitric oxide synthase (eNOS) expression was evaluated with immunohistochemistry.

RESULTS

Compared to the control group, the 20 mg/kg/d simvastatin group presented with lower absolute (p = 0.005) and relative prostate weight (p = 0.009). The basal cells and columnar cells presented with edema, condensed heterochromatin in interstitial fibroblast nuclei, widened nucleus gaps, and decreased mitochondria and endoplasmic reticulum in the 10 mg/kg/d simvastatin group, these changes were more pronounced in the 20 mg/kg/d simvastatin group. The IL-6 levels in the 10 and 20 mg/kg/d simvastatin groups were lower than those of the controls (p = 0.005 and p = 0.008). The IGF-1 levels of the 20 mg/kg/d simvastatin group were reduced compared to the control group (p = 0.016).

CONCLUSIONS

Simvastatin can delay and inhibit prostatic hyperplasia and progression in SHR. These actions may be mediated through the suppression of inflammatory and growth factors.

Association of prostate specific antigen concentration with lifestyle characteristics in Korean men

We investigated the relationships between demographics, lifestyle characteristics, and serum total prostate specific antigen (PSA) concentration and examined the population-based distribution of total PSA by age among 2,246 Korean men with a median age of 45 years. We obtained data about demographic and lifestyle characteristics based on self-reporting using a questionnaire. We also performed physical examinations, anthropometric measurements, and biochemical measurements. The PSA concentration increased with age and there was a significant difference in total PSA concentration between the age groups of 21-60 years and >60 years. Age>60 years, height≥1.8 m, a low frequency of alcohol consumption, and taking nutritional supplements showed a significantly increased odds ratio for increased PSA when 3.0 ng/ mL was chosen as the PSA cut-off level. Smoking status, BMI, percent body fat, diabetes mellitus, fatty liver, herbal medicine use, vitamin use, and diet were not significantly associated with total PSA regardless of the cut-off level. When interpreting a single PSA test, height, alcohol consumption, and nutritional supplement use should be considered, in addition to age.

High incidence of prostate cancer metastasis in Afro-Brazilian men with low educational levels: a retrospective observational study

BACKGROUND

This study investigated factors related to ethnicity and educational level, their correlation with tumor stage at the time of diagnosis, and their influence on treatment outcomes in patients with prostate cancer.

METHODS

In this retrospective observational study, we analyzed the medical records of 1,349 male patients treated for prostatic adenocarcinoma. We collected information about sociodemographic variables, including educational level and self-reported skin color. We also classified the disease according whether it was to more likely to present with metastasis and measured the tumor response to treatment.

RESULTS

Less-educated (<8 years of education) individuals were 4.8 times more likely to develop metastasis than those with more education (>11 years of education; p < 0.001). Similarly, patients with a self-reported black skin color had a 300% increased risk of metastasis at diagnosis (p = 0.001). Distant metastasis was independently correlated with worse outcomes, such that individuals with distant metastasis were 10 times more likely to die than were those without distant metastasis.

CONCLUSIONS

Patients with self-reported black skin color and <8 years of education were more likely to display advanced disease at the time of diagnosis compared with their counterparts. Only the presence of metastasis was independently associated with mortality or progressive disease.

The association between obesity and urinary tract infection

BACKGROUND

Few studies examined the relationship between obesity and urinary tract infection (UTI), showing inconsistent results. This study aims to examine the association between obesity and UTI, and to assess whether this association is independent of diabetes mellitus and 25(OH)D level.

METHODS

Using the computerized database of the largest healthcare provider in Israel, we identified a cohort of subjects ≥18years old with available BMI and serum 25(OH)D level measurements between January 2009 and December 2009. The cohort was followed for the first UTI diagnosis from January 2010 through June 2011. Cox proportional hazard model was used to test the relationship between obesity and UTI.

RESULTS

During follow-up, 25,145/110,736 (22.7%) females, and 4032/42,703 (9.4%) males had UTI. The crude HR for UTI in those with BMI≥50 compared to BMI<25 was 2.54 (95% CI, 1.50-4.30) in males and 1.39 (1.14-1.69) in females. After adjusting for age, 25(OH)D level, and history of diabetes mellitus, the HR for UTI in those with BMI≥50 compared to BMI<25 was 2.38 (1.40-4.03) in males and 1.25 (1.03-1.52) in females. The HR for those in the lowest quartile of serum 25(OH)D compared to the highest quartile was 1.23 (1.13-1.35) in males and 0.98 (0.95-1.02) in females. The HR for subjects with diabetes was 1.23 (1.16-1.32) in males, and 1.25 (1.20-1.28) in females.

CONCLUSIONS

Obesity is independently associated with UTI particularly in males. Low serum 25(OH)D levels are associated with increased risk of UTI in males.

Obesity and benign prostatic hyperplasia: clinical connections, emerging etiological paradigms and future directions

PURPOSE

Benign prostatic hyperplasia is a highly prevalent disease in older men with substantial adverse effects on public health. Classic etiological paradigms for benign prostatic hyperplasia focus on nonmodifiable risk factors. However, obesity also potentially promotes benign prostatic hyperplasia.

MATERIALS AND METHODS

We performed a structured, comprehensive literature review to identify studies of obesity, benign prostatic hyperplasia, lower urinary tract symptoms and physical activity.

RESULTS

A preponderance of published evidence suggests strong positive associations of obesity with benign prostatic hyperplasia and lower urinary tract symptoms. This evidence encompasses most established metrics of adiposity, including body mass index, waist circumference and waist-to-hip ratio, and falls under 3 general categories, including prostate volume, clinical benign prostatic hyperplasia and lower urinary tract symptoms. 1) Prior studies consistently showed that increased adiposity is positively associated with radiographically determined prostate volume and enlargement, suggesting that obesity promotes prostate growth. 2) Most studies revealed that obesity increases the risk of clinical benign prostatic hyperplasia by several measures, including the initiation of benign prostatic hyperplasia medical treatment, noncancer prostate surgery, physician diagnosed benign prostatic hyperplasia, histological diagnosis and urinary flow rate. 3) Prior studies demonstrated that obesity increases the risk of lower urinary tract symptoms, as measured by a validated questionnaire. Also, most studies showed that physical activity significantly decreases the risk of benign prostatic hyperplasia.

CONCLUSIONS

Obesity markedly increases the risk of benign prostatic hyperplasia. Since physical activity decreases the risk of benign prostatic hyperplasia, these observations support the development of novel prevention strategies and treatment targeted toward adiposity, weight loss and lifestyle.

Body mass index and risk of BPH: a meta-analysis

BACKGROUND

Epidemiological studies have reported conflicting results relating obesity to BPH. A meta-analysis of cohort and case-control studies was conducted to pool the risk estimates of the association between obesity and BPH.

METHODS

Eligible studies were retrieved by both computer searches and review of references. We analyzed abstracted data with random effects models to obtain the summary risk estimates. Dose-response meta-analysis was performed for studies reporting categorical risk estimates for a series of exposure levels.

RESULTS

A total of 19 studies met the inclusion criteria of the meta-analysis. Positive association with body mass index (BMI) was observed in BPH and lower urinary tract symptoms (LUTS) combined group (odds ratio=1.27, 95% confidence intervals 1.05-1.53). In subgroup analysis, BMI exhibited a positive dose-response relationship with BPH/LUTS in population-based case-control studies and a marginal positive association was observed between risk of BPH and increased BMI. However, no association between BPH/LUTS and BMI was observed in other subgroups stratified by study design, geographical region or primary outcome.

CONCLUSIONS

The overall current literatures suggested that BMI was associated with increased risk of BPH. Further efforts should be made to confirm these findings and clarify the underlying biological mechanisms.

A novel equation and nomogram including body weight for estimating prostate volumes in men with biopsy-proven benign prostatic hyperplasia

Anthropometric measurements, e.g., body weight (BW), body mass index (BMI), as well as serum prostate-specific antigen (PSA) and percent-free PSA (%fPSA) have been shown to have positive correlations with total prostate volume (TPV). We developed an equation and nomogram for estimating TPV, incorporating these predictors in men with benign prostatic hyperplasia (BPH). A total of 1852 men, including 1113 at Tokyo Medical and Dental University (TMDU) Hospital as a training set and 739 at Cancer Institute Hospital (CIH) as a validation set, with PSA levels of up to 20 ng ml(-1), who underwent extended prostate biopsy and were proved to have BPH, were enrolled in this study. We developed an equation for continuously coded TPV and a logistic regression-based nomogram for estimating a TPV greater than 40 ml. Predictive accuracy and performance characteristics were assessed using an area under the receiver operating characteristics curve (AUC) and calibration plots. The final linear regression model indicated age, PSA, %fPSA and BW as independent predictors of continuously coded TPV. For predictions in the training set, the multiple correlation coefficient was increased from 0.38 for PSA alone to 0.60 in the final model. We developed a novel nomogram incorporating age, PSA, %fPSA and BW for estimating TPV greater than 40 ml. External validation confirmed its predictive accuracy, with AUC value of 0.764. Calibration plots showed good agreement between predicted probability and observed proportion. In conclusion, TPV can be easily estimated using these four independent predictors.

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.

Diabetes treatment and progression of benign prostatic hyperplasia in community-dwelling black and white men

OBJECTIVE

To conduct a study to determine whether diabetes treatment is associated with benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS) and progression in black and white men. Diabetes has been associated with BPH and LUTS in aging men.

METHODS

Using the Olmsted County Study of Urinary Symptoms and Health Status among Men and the Flint Men's Health Study, we examined how the use of medical therapy (eg, insulin regimens, oral hypoglycemics) related to changes in LUTS severity, maximal urinary flow rate measured by uroflowmetry, prostate volume determined by transrectal ultrasonography, and serum prostate-specific antigen concentrations.

RESULTS

Of the 2226 men participating in the Olmsted County Study of Urinary Symptoms and Health Status among Men and the Flint Men's Health Study, 186 men reported a history of diabetes, 76.9% of whom were treated with medical therapy. Overall, the men with diabetes had significantly greater odds of moderate/severe LUTS (age- and race-adjusted odds ratio 1.37, 95% confidence interval 1.00-1.87) compared with those without diabetes. However, among the diabetic men, those not taking medication had greater odds of moderate/severe LUTS than those taking medication. This association among men not taking medication was seen for 5 of the 7 individual symptoms. The prostate volume and prostate-specific antigen level were not significantly associated with diabetes treatment. No significant differences were observed for the annual change in BPH characteristics by diabetes treatment status.

CONCLUSION

These findings suggest that the presence of diabetes and subsequent poor glycemic control might be less related to prostate growth and more to the dynamic components of lower urinary tract function. Additional evaluations of the associations between glycemic control and BPH progression are warranted.

Predictive factors for urinary retention following kidney transplantation in male patients

OBJECTIVE

Urinary retention frequently occurs in patients after kidney transplantation. This study aimed to identify predictive factors for urinary retention requiring transurethral resection of the prostate (TURP) following kidney transplantation.

MATERIAL AND METHODS

Seventy male patients (median age 56 years, range 37-73 years) who underwent kidney transplantation between 1995 and 2006, and experienced urinary retention and consecutively required TURP, were studied retrospectively. Residual diuresis before transplantation, duration of dialysis, patient age, prostate size, rejection reactions, transplant loss, combined kidney and pancreas transplantation, type 1 and 2 diabetes mellitus, and carcinoma of the prostate were evaluated as predictive factors.

RESULTS

Duration of dialysis longer than 120 months (p = 0.0174), patient age over 60 years (p = 0.0045) and the absence of diabetes (n = 46, p = 0.0029) were associated with a significantly higher risk of urinary retention requiring TURP following kidney transplantation. Residual diuresis, prostate size, frequency of rejection reactions, transplant loss and detection of carcinoma, however, could not be identified as predictive factors.

CONCLUSIONS

In male patients after kidney transplantation with a long history of dialysis, early TURP due to urinary retention must be anticipated. Surprisingly, the presence of type 1 or 2 diabetes seems to prevent the occurrence of retention, independently of age.

Androgenetic alopecia as an early marker of benign prostatic hyperplasia

BACKGROUND

Androgenetic alopecia (AGA) and benign prostatic hyperplasia are both androgen-dependent entities that respond to the blocking of 5-alpha-reductase.

OBJECTIVES

The objective of this study was to determine whether prostatic volumes and urinary flow changes were higher in patients with early-onset AGA than in healthy control subjects.

METHODS

This was an observational case-control study of 87 men: 45 with early-onset AGA diagnosed in the dermatology department and 42 control subjects. End-point variables were prostatic volume, measured by transrectal ultrasound, and urinary flow, measured by urinary flowmetry. A hormone study was performed on all participants, and the International Prostate Symptom Score and International Index of Erectile Function score were determined.

RESULTS

The groups did not significantly differ in mean age (cases, 52.7 years vs control subjects, 49.8 years; P = .12). Patients with AGA had significantly higher mean prostate volume (29.65 vs 20.24 mL, P < .0001), International Prostate Symptom Score (4.93 vs 1.23, P < .0001), and prostate-specific antigen value (1.53 vs 0.94 ng/mL, P < .0001) and significantly lower maximum urinary flow (14.5 vs 22.45 mL/s, P < .0001) versus control subjects. Binary logistic regression analysis showed a strong association between the presence of AGA and benign prostatic hyperplasia after adjusting for age, urinary volume, urination time, International Prostate Symptom Score, abdominal obesity, glucose levels, systolic blood pressure, insulin levels, fibrinogen, and C-reactive protein (odds ratio = 5.14, 95% confidence interval 1.23-47.36, P = .041).

LIMITATIONS

The study of larger sample sizes would facilitate stratified analyses according to the Ebling type of androgenetic alopecia.

CONCLUSION

There is a relationship between the presence of AGA and prostate growth-associated urinary symptoms, likely attributable to their pathophysiological similarity. This study suggests that early-onset AGA may be an early marker of urinary/prostatic symptomatology. Future studies may clarify whether treatment of patients with AGA may benefit the concomitant benign prostatic hypertrophy, which would be present at an earlier stage in its natural evolution.

Does pre-existing diabetes affect prostate cancer prognosis? A systematic review

To summarize the influence of pre-existing diabetes on mortality and morbidity in men with prostate cancer. We searched MEDLINE and EMBASE from inception through 1 October 2008. Search terms were related to diabetes, cancer and prognosis. Studies were included if they reported an original data analysis of prostate cancer prognosis, compared outcomes between men with and without diabetes and were in English. Titles, abstracts and articles were reviewed independently by two authors. Conflicts were settled by consensus or third review. We abstracted data on study design, analytic methods, outcomes and quality. We summarized mortality and morbidity outcomes qualitatively and conducted a preliminary meta-analysis to quantify the risk of long-term (>3 months), overall mortality. In total, 11 articles were included in the review. Overall, one of four studies found increased prostate cancer mortality, one of two studies found increased nonprostate cancer mortality and one study found increased 30-day mortality. Data from four studies could be included in a preliminary meta-analysis for long-term, overall mortality and produced a pooled hazard ratio of 1.57 (95% CI: 1.12-2.20). Diabetes was also associated with receiving radiation therapy, complication rates, recurrence and treatment failure. Our analysis suggests that pre-existing diabetes affects the treatment and outcomes of men with prostate cancer.

Diet, physical activity and energy balance and their impact on breast and prostate cancers

Obesity, physical activity status and circulating levels of sex steroid hormones and growth factor proteins are intrinsically linked to energy balance. Epidemiological studies have previously reported associations between these factors and the risk of hormone-related cancers such as prostate and breast cancer in men and postmenopausal women. An increasing number of intervention studies in 'at-risk' populations and cancer survivors are now investigating the effects of lifestyle interventions that promote negative energy balance on circulating levels of sex hormones and growth factor proteins as surrogate markers of cancer risk. Evidence from these studies suggests that lifestyle interventions can improve insulin sensitivity, alter the balance of circulating sex steroid hormones and insulin-like growth factor (IGF) axis proteins (including IGF-1 and the IGF binding proteins 1 and 3) and change the functioning of immune cells in peripheral blood. Such changes could influence the risk of developing hormone-related cancers, as well as having the potential to improve disease-free survival in patients recovering from cancer treatment. However, despite promising results, the methodological quality of most intervention studies has been limited due to small subject numbers, lack of adequate control groups or non-randomised designs and the absence of long-term follow-up measures. More intervention studies with randomised controlled designs, higher numbers of subjects and longer-term follow-up measures are needed to establish which combination of specific dietary and physical activity interventions work best for reducing risk in 'at-risk' populations and survivors, optimal dose-response relationships and the magnitude of change in surrogate markers of cancer risk that is required to induce a protective effect.

Effects of obesity on lower urinary tract symptoms in Korean BPH patients

We analyzed the effects of obesity on lower urinary tract symptoms (LUTSs) in Korean benign prostatic hyperplasia (BPH) patients. This is a multicenter, cross-sectional, prospective study conducted in four centers in Korea. A total of 602 men with LUTSs secondary to BPH were included. BPH/LUTSs cases were men aged >/= 40 years with international prostate symptom scores (IPSS) > or = 8 points. Height, weight and waist circumference were measured. Among the 602 patients, 156 patients had a waist circumference above 90 cm, representing central obesity, and 215 patients had a body mass index above 25 kg m(-2). Waist circumference was positively correlated with prostate volume (P = 0.034). Men with waist circumference > 90 cm experienced a 1.36-fold increased risk of severe LUTSs (95% CI 0.82-2.41) compared with men with waist circumference < or = 90 cm. Prostate volume was positively correlated with urgency and nocturia in men with central obesity. In this population of Korean men diagnosed with BPH, central obesity rather than overall obesity seems to be the more important predictor of LUTSs correlated with BPH.

Associations between diabetes and clinical markers of benign prostatic hyperplasia among community-dwelling Black and White men

OBJECTIVE

The aim of this study was to examine associations between diabetes and clinical markers of benign prostatic hyperplasia (BPH) in community-dwelling white and black men aged 40-79 years.

RESEARCH DESIGN AND METHODS

Data from the Olmsted County Study of Urinary Symptoms and Health Status and the Flint Men's Health Study were combined for a total study sample of 2,484 men. Severity of lower urinary tract symptoms (LUTS), peak urinary flow rates, prostate volume, and serum prostate-specific antigen (PSA) levels were examined by self-reported physician-diagnosed diabetes.

RESULTS

Overall, 170 men (6.8%) reported a history of diabetes. Increased irritative LUTS and specifically nocturia were positively associated with diabetes. These patterns were consistent across race and persisted after adjustment for age, BMI, and various indicators of socioeconomic status. Furthermore, the relationship between irritative LUTS and diabetes was greater in black men. No significant associations were observed between diabetes and prostate volume, PSA level, and peak urinary flow rate.

CONCLUSIONS

Our multiethnic community-based study demonstrates positive associations between diabetes and irritative LUTS and nocturia. Moreover, the association between irritative LUTS and diabetes is increased in black men. There was no strong evidence for an association between diabetes and BPH across measures more specific to BPH (i.e., prostate volume, PSA, and peak urinary flow rate). Taken together, our findings suggest that the presence of diabetes may be less related to prostate growth and more related to the dynamic components of lower urinary tract function. Further evaluations of the association between diabetes and BPH and related racial variations are warranted.

Association of IGF-1 and IGFBP-3 with lower urinary tract symptoms in the third national health and nutrition examination survey

BACKGROUND

Benign growth of the prostate is thought to contribute to lower urinary tract symptoms (LUTS) in older men. It is, however, unclear which factors induce prostate growth in these men. We examined the association of insulin-like growth factor (IGF)-1 and its major binding protein IGFBP-3 with LUTS in a representative US study.

METHODS

We included men 60 years and older who participated in the morning session of the Third National Health and Examination Survey (NHANES III) between 1988 and 1994. Men were classified as cases (n = 91) if they reported at least three of four LUTS (nocturia, incomplete emptying, hesitancy, or weak stream) but had not had non-cancer prostate surgery in the past. Controls were men without symptoms and surgery (n = 220). All results were weighted to account for sampling probability in NHANES III. IGF-1 and IGFBP-3 were measured by ELISA and IRMA, respectively.

RESULTS

After mutual adjustment, men in the highest tertile of serum IGF-1 concentration had a non-significantly higher odds of LUTS than men in the lowest tertile (odds ratio (OR) = 3.20; 95% confidence interval (CI) 0.89-11.4; p-trend = 0.09]. A high concentration of IGFBP-3 was inversely related to the odds of LUTS (OR = 0.25; 95% CI 0.08-0.81; p-trend = 0.02).

CONCLUSION

A high IGFBP-3 level might affect LUTS by decreasing the bioavailability of IGF-1 or independent of IGF-1 by up-regulating apoptosis, and, thus, limiting its growth promoting effects on the prostate.

Modifiable risk factors for benign prostatic hyperplasia and lower urinary tract symptoms: new approaches to old problems

PURPOSE

Benign prostatic hyperplasia is generally not regarded as a preventable disease. However, accumulating evidence suggests that modifiable factors may influence the risk of benign prostatic hyperplasia and lower urinary tract symptoms.

MATERIALS AND METHODS

A structured, comprehensive literature review was done to identify modifiable risk factors for benign prostatic hyperplasia and lower urinary tract symptoms among observational studies of older men.

RESULTS

Outcome measures used to define benign prostatic hyperplasia in clinical studies include histological analysis of prostate tissue, radiographically determined prostate enlargement, acute urinary retention, decreased urinary flow rate, pressure flow studies consistent with bladder outlet obstruction, history of benign prostatic hyperplasia surgery, physician diagnosed benign prostatic hyperplasia and American Urological Association symptom score or International Prostate Symptom Score. Factors that potentially increase the risk of benign prostatic hyperplasia and lower urinary tract symptoms include obesity and diabetes. Factors that potentially decrease the risk include increased physical activity and moderate alcohol consumption. Other candidate factors for which clear risk patterns have not yet emerged are dyslipidemia, hypertension, smoking, diet and environment.

CONCLUSIONS

Obesity, diabetes, physical activity and alcohol intake may substantially influence the risk of benign prostatic hyperplasia and lower urinary tract symptoms in older men. Further analyses of these and other potential modifiable risk factors may identify novel interventions for the prevention, diagnosis and treatment of these highly prevalent conditions.

Obesity and Benign Prostatic Enlargement: A Large Observational Study in China

OBJECTIVES

To investigate the associations of prostate enlargement with obesity and hypertension in Chinese men.

METHODS

A total of 649 men from Zhejiang, China were invited to the Family Planning Station of Wenlin to undergo prostate volume measurement with transrectal ultrasonography. Benign prostatic enlargement (BPE) has been defined as a prostate volume larger than 20 cm3. The associations between BPE and prostate volume with body mass index (BMI) and blood pressure were evaluated by multivariate linear and logistic regression analyses.

RESULTS

Overweight (BMI of 25 or more but less than 28 kg/m2) and obese (BMI of 28 kg/m2 or more) men experienced a significantly increased age-adjusted risk of BPE compared with men with a lower BMI (odds ratio 1.63, 95% confidence interval 1.16 to 2.30, and odds ratio 2.26, 95% confidence interval 1.11 to 4.59, respectively). Each 0.37-kg/m2 increase (95% confidence interval 0.18 to 0.57, P <0.01) in the BMI was associated with a 1-cm3 increase in prostate volume. No associations were observed between hypertension and BPE.

CONCLUSIONS

This is the first study to provide evidence that the BMI is positively associated with prostate volume in the Chinese population. Obese Chinese men are at increased risk of an enlarged prostate compared with nonobese Chinese men.

Prostate volume modifies the association between obesity and prostate cancer or high-grade prostatic intraepithelial neoplasia

The relationship between obesity and prostate cancer remains unclear. We investigated the effect of prostate volume on the obesity and prostate cancer association. With a multi-centered, rapid-recruitment protocol, weight and body size measurements were collected prior to diagnosis, and medical charts were reviewed for pathology results (n = 420 controls, 119 high-grade prostatic intraepithelial neoplasia (PIN) cases, and 286 cancer cases (41% Gleason > 6). In multivariable logistic regression models adjusting for age, PSA levels and history, DRE results, and number of cores at biopsy, the association between BMI and cancer was restricted to men with a smaller prostate volume (volume < 40 cm(3): OR(BMI > or = 30) = 2.17 (1.09, 4.32), p (trend) = 0.02; volume > or = 40 cm(3): OR(BMI > or = 30) = 0.77 (0.34, 1.77), p (trend) = 0.17; p (interaction) = 0.03). Similarly, the WHR and PIN association was significantly modified by prostate volume (volume < 40 cm(3): OR((WHR: Tertile 3 vs. T1)) = 3.76 (1.54, 9.21) (p (trend) < 0.01); volume > or = 40 m(3): OR((WHR: T3 vs. T1)) = 0.63 (0.32, 1.23) (p (trend) = 0.17); p (interaction) < 0.01). In conclusion, prostate volume acts as a modifier, and BMI and WHR are significantly associated with prostate cancer or PIN, respectively, in the absence of biopsy sampling error derived from obesity-related prostate enlargement.

Anthropometric and metabolic factors and risk of benign prostatic hyperplasia: a prospective cohort study of Air Force veterans

OBJECTIVES

The relationship between anthropometric and metabolic factors and benign prostatic hyperplasia (BPH) is poorly understood. We investigated the associations of BPH with anthropometric and metabolic parameters in this prospective study of Vietnam War veterans.

METHODS

A total of 1206 participants in the comparison arm of the Air Force Health Study with a median follow-up of 15.6 years were included in this study. The "Ranch Hand" group, occupationally exposed to herbicides, was excluded to eliminate any confounding from exposure to herbicides. BPH was determined by medical record review using the International Classification of Diseases and Related Problems, Ninth Revision. We used Cox proportional hazards regression models for the statistical analysis.

RESULTS

The median age for BPH diagnosis was 58.6 years. On multivariate analyses, increasing age (relative risk [RR] 1.14, 95% confidence interval [CI] 1.12 to 1.17), height (RR 1.02, 95% CI 1.004 to 1.03), and fasting blood glucose (RR 1.004, 95% CI 1.001 to 1.007) were associated with increased risk. The effect of age varied with the duration of follow-up. A greater systolic blood pressure (RR 0.992, 95% CI 0.986 to 0.997) was associated with decreased risk of BPH. A dose-response effect was seen for age, height, and systolic blood pressure. No effect was seen for weight, body mass index, change in weight or body mass index, lipids, thyroid hormone status, or the metabolic syndrome.

CONCLUSIONS

The risk of BPH increased with increasing age, height, and fasting blood glucose levels. The risk was decreased with a greater systolic blood pressure. No relationship was seen between BPH and metabolic syndrome, weight, body mass index, lipid level, or thyroid hormone status.

The association between body size, prostate volume and prostate-specific antigen

Increasing prostate volume contributes to urinary tract symptoms and may obscure prostate cancer detection. We investigated the association between obesity and prostate volume, prostate-specific antigen (PSA) and PSA density among 753 men referred for prostate biopsy. Among men with a negative biopsy, prostate volume significantly increased approximately 25% from the lowest to highest body mass index (BMI), waist or hip circumference or height categories. PSA was 0.7 ng/ml lower with a high waist-to-hip ratio. These associations were less consistent among subjects diagnosed with high-grade prostatic intraepithelial neoplasia or cancer. Our data suggest that obesity and height are independently associated with prostate volume..

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.

Racial and anthropometric differences in plasma levels of insulin-like growth factor I and insulin-like growth factor binding protein-3

OBJECTIVES

To analyze the differences in the plasma levels of insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP-3), and their ratio between black and white men while controlling for factors that could confound the relationship between IGF levels and race. Furthermore, we analyzed the association between age, height, prostate-specific antigen level, digital rectal examination status, and current smoking status on IGF levels separately in black and white men. Greater levels of IGF-I and lower levels of IGFBP-3 have been associated with an increased risk of prostate cancer in many studies.

METHODS

A cross-sectional analysis was performed on 171 white and 130 black men aged 40 to 80 years. Multiple linear regression analysis was used to model the data separately for blacks and whites. A chi-square global test was used to test for racial differences in regression curves.

RESULTS

Our results indicated that black men have lower levels of IGFBP-3 and IGF-I and a greater IGF-I/IGFBP-3 ratio than white men across all ages younger than 70, with and without an adjustment for height. We found racial differences in the effect of age and height on levels of IGF-I, IGFBP-3, and the molar ratio. Age had an inverse correlation with IGF-I and IGFBP-3 levels in whites, but no such relationship in blacks.

CONCLUSIONS

The differences in IGF levels between blacks and whites may explain some of the racial disparity in prostate cancer risk. Because age and height affect IGF levels differently in black and white men, future analysis exploring the determinants of IGF levels may need to be stratified by race.

History of weight and obesity through life and risk of benign prostatic hyperplasia

OBJECTIVE

The relation of anthropometric measures, diabetes, hypertension and hyperlipidemia with benign prostatic hyperplasia (BPH) risk was investigated.

DESIGN

Hospital-based case-control study.

SUBJECTS

Cases were 1369 men with histologically confirmed BPH, and controls were 1451 men below 75 y, admitted to hospital for acute non-neoplastic diseases.

MEASUREMENTS

Using a structured questionnaire, trained interviewers collected information on self-reported height and weight, and measured waist and hip circumference of patients. The odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional multiple logistic regression models.

RESULTS

Compared to the corresponding lowest quartile, the OR for the highest one were 0.76 (95% CI 0.59-0.98) for body weight, 0.71 (95% CI 0.54-0.94) for waist-to-hip ratio and 0.87 (95% CI 0.70-1.09) for body mass index (BMI, kg/m(2)). Compared to a lowest lifelong BMI <20.7 kg/m(2), the OR was 1.56 (95% CI 1.25-1.95) for a lowest lifelong BMI > or =23.7 kg/m(2). The OR was 0.74 (95% CI 0.60-0.93) for a lifelong increase of BMI > or =6.1 kg/m(2), compared to <1.6 kg/m(2). No association emerged for history of diabetes, hypertension and hyperlipidemia.

CONCLUSIONS

Overweight was modestly, inversely related to BPH. The hypothesis of reduced testosterone levels in obese individuals may explain the different BPH risk and need to be tested.