Rates of False-Negative Screening in Prostate Specific Antigen Secondary to 5-Alpha Reductase Inhibitor Usage: A Quality-Improvement Initiative

ABSTRACT Purpose Patients often take 5-alpha reductase inhibitors (5-ARIs) for the management of benign prostatic hyperplasia. However, 5-ARIs can decrease prostate specific antigen (PSA) by approximately half and therefore may lead to false negative PSA tests. We investigated false-screening rates in men on 5-ARIs undergoing PSA testing and whether ordering physicians noticed false negative findings. Materials and Methods A single institution, retrospective study was conducted on patients with a PSA value documented between 2014 and 2017. Patient demographics, PSA results, 5-ARI usage, and providing clinician characteristics were collected. Published normal PSA values were used to determine PSA test positivity; values for those on 5-ARIs were doubled. Results A total of 29,131 men were included. 1,654 (5.7%) were prescribed 5-ARIs at least 12 months prior to PSA evaluation. 118 men (7.1%) had a value that would be positive if corrected for 5-ARI usage, 33 (27.9%) of which had no indication that the provider had noted this. There was no effect on rates of false negative values if the PSA was ordered by a different provider than the one who prescribed the 5-ARI (p = 0.837). However, if the provider who ordered the PSA test was an urologist, the likelihood that a false negative value would be identified was lower (p=0.001). Conclusions More than a quarter of men with false negative tests were missed. This occurred more often when the ordering provider was not an urologist. An educational opportunity exists to improve the quality of PSA testing by preventing false negative tests.

Clinical Risk Factors Associated With Small Renal Mass Malignant Histology in a Multi-Ethnic Population Undergoing Partial Nephrectomy.

INTRODUCTION: Small renal masses (SRMs) are often incidentally diagnosed, and a large proportion are malignant. However, there is a paucity of data describing predictors of malignancy in minority patients with SRMs. Thus, our goal was to examine clinical risk factors associated with SRM malignant histology in patients undergoing partial nephrectomy (PN) a diverse, urban academic center. MATERIALS AND METHODS: Patients with a SRM undergoing PN at a single institution between 2010 to 2018 were reviewed. Demographic, clinical, and imaging characteristics were compared to pathology results. Logistic regression was used to examine associations between demographic/clinical variables for malignant and high-grade histology. RESULTS: In total, 331 patients who underwent PN for SRM were included. Of those, 264 (79.8%) had malignant histology while 67 (20.2%) had benign histology. The proportions of men and of current smokers were significantly higher among patients with malignant histology. In multivariate models, non-Hispanic Black (NHB) patients had increased odds of having malignant histology (OR 2.46, 95% CI: 1.01-5.99, P = .048) and current smokers (OR = 4.02; 95% CI 1.14-14.18, P = .031). Hispanic patients had a 3-fold increased risk of high-grade RCC (OR 3.06, 95% CI: 1.19-7.87, P = 0.02) compared to Non-Hispanic White patients. CONCLUSION: In our population, male sex, smoking, and NHB race/ethnicity was associated with an increased risk of malignancy in patients undergoing partial nephrectomy for SRM. Older age and Hispanic race/ethnicity were associated with high grade RCC. Our results suggest that urologists should exercise a higher level of vigilance in managing and treating SRM among NHB and Hispanic patients.

Rates of False-Negative Screening in Prostate Specific Antigen Secondary to 5-Alpha Reductase Inhibitor Usage: A Quality-Improvement Initiative.

PURPOSE: Patients often take 5-alpha reductase inhibitors (5-ARIs) for the management of benign prostatic hyperplasia. However, 5-ARIs can decrease prostate specific antigen (PSA) by approximately half and therefore may lead to false negative PSA tests. We investigated false-screening rates in men on 5-ARIs undergoing PSA testing and whether ordering physicians noticed false negative findings. MATERIALS AND METHODS: A single institution, retrospective study was conducted on patients with a PSA value documented between 2014 and 2017. Patient demographics, PSA results, 5-ARI usage, and providing clinician characteristics were collected. Published normal PSA values were used to determine PSA test positivity; values for those on 5-ARIs were doubled. RESULTS: A total of 29,131 men were included. 1,654 (5.7%) were prescribed 5-ARIs at least 12 months prior to PSA evaluation. 118 men (7.1%) had a value that would be positive if corrected for 5-ARI usage, 33 (27.9%) of which had no indication that the provider had noted this. There was no effect on rates of false negative values if the PSA was ordered by a different provider than the one who prescribed the 5-ARI (p = 0.837). However, if the provider who ordered the PSA test was an urologist, the likelihood that a false negative value would be identified was lower (p=0.001). CONCLUSIONS: More than a quarter of men with false negative tests were missed. This occurred more often when the ordering provider was not an urologist. An educational opportunity exists to improve the quality of PSA testing by preventing false negative tests.

Association of Obesity and Diabetes With Prostate Cancer Risk Groups in a Multiethnic Population.

INTRODUCTION: Obesity and diabetes mellitus (DM) have been associated with prostate cancer (PCa) risk, but data examining their combined effects on aggressive PCa are sparse, particularly among non-Hispanic Black and Hispanic men. We investigated the associations of obesity and DM in relation to National Comprehensive Cancer Network (NCCN) PCa risk groups in a racially-diverse patient population. PATIENTS AND METHODS: We abstracted demographic and clinical data from men who underwent radical prostatectomy at our institution between 2005 and 2019. Patients were classified into three NCCN PCa risk-groups: low, intermediate and high-risk. Logistic regression models were used to examine the independent and combined associations of body mass index (BMI)/obesity and DM with risks of intermediate and high-risk PCa, adjusting for age and race/ethnicity. RESULTS: A total of 1303 men with PCa (average age 60 ± 6.9 years) were analyzed. The majority were non-Hispanic Black (N = 493, 38%) or Hispanic (N = 407, 31%). The prevalence of obesity (BMI ≥ 30 kg/m2) and DM was 29.3% (N = 382) and 28.3% (N = 369), respectively. In multivariate analyses, obesity was independently associated with an odds ratio (OR) = 2.21 of high-risk PCa (95% CI: 1.28-3.81), while DM was associated with an OR = 1.49 (95% CI: 1.05-2.11) of intermediate-risk PCa. Compared to non-obese men without diabetes, men with BMI ≥ 30 and DM had increased risks of both intermediate (OR = 1.93; 95% CI 1.12-3.43) and high-risk PCa (OR = 2.40; 95% CI 1.22-4.73). Interestingly, most of the association of high-risk PCa was driven by obesity. CONCLUSION: In this multiethnic population both obesity and DM were independently associated with intermediate- and high-risk PCa; however, most of the association for high-risk cancer was driven by obesity. Our results corroborate findings that obesity increases the risk of aggressive PCa; however, results regarding DM need to be confirmed in other large multiethnic populations.

The impact of surgical downgrading on prostate cancer recurrence: systematic review and analysis of a multiethnic population.

OBJECTIVE: To perform a systematic review and a retrospective cohort analysis evaluating the rates of surgical downgrading of prostate cancer (PCa) from biopsy (PBx) to radical prostatectomy (RP), and their association with biochemical recurrence (BCR) in a multiethnic population. METHODS: A systematic review of PubMed and other databases was performed. We included retrospective studies evaluating the relationship between surgical downgrading and BCR-free survival. Data regarding Gleason score (GL) downgrading were abstracted from the articles and categorized as follows: GL8-10 to GL7, GL7 to GL6, and GL 7(4 + 3) to GL7(3 + 4). We also performed a retrospective cohort review of patients who underwent RP at our institution from 2005 through 2020. Kaplan-Meier survival analysis and Cox proportional hazards models were used to compare BCR among downgraded versus non-downgraded men. RESULTS: Systematic review yielded 137 abstracts; of these, 36 full-texts were reviewed, 8 of which were included in our systematic review. Despite substantial variability, all showed that GL at RP is one of the most important factors of BCR-free survival. A total of 1,484 men with PCa were analyzed from our institution. On multivariate analysis, GL7 to GL6 downgrading (HR = 0.50, p = 0.022) and GL8-10 to GL7 downgrading (HR = 0.42, p = 0.011) were associated with reduced risk of BCR when compared to men with GL7 and GL8-10 concordance, respectively. However, GL7(4 + 3) to GL7(3 + 4) downgrading was not significantly associated with reduced BCR (HR = 0.56, p = 0.12), when compared to GL7(4 + 3) concordance, although HR was similar. CONCLUSION: Surgical downgrading at RP was associated with a reduced risk of BCR compared to GL concordant disease, and these findings have been validated within our multiethnic population. Pathologic downgrading at the time of RP may be a more useful predictor of subsequent BCR in comparison to that associated with GL concordant pathology.

Finasteride Use and Risk of Bladder Cancer in a Multiethnic Population.

PURPOSE: Finasteride use has been associated with a reduced incidence of bladder cancer. However, the majority of studies have been conducted primarily in East Asian or White populations. Given differences in the incidence of bladder cancer among racial/ethnic groups, it is important to determine whether the effect of finasteride use on bladder cancer varies by race/ethnicity. MATERIALS AND METHODS: We identified all patients with a diagnosis of benign prostatic hyperplasia between 2000 and 2016 at our academic health center in Bronx, New York via an electronic medical record database. We then identified patients who were prescribed finasteride, and those who developed bladder cancer during followup. We used competing risk analysis to examine associations of finasteride use with risk of bladder cancer, adjusting for age, smoking and race/ethnicity. RESULTS: We identified 42,406 patients with benign prostatic hyperplasia (average±SD age 67±12.9 years), of whom 27.7% were Black and 14.8% were Hispanic. Finasteride was prescribed in 5,698 patients (13.4%). Bladder cancer was diagnosed in 84 of 5,698 finasteride users (1.5%), compared to 762 of 36,708 nonusers (2.1%, log-rank p=0.003). Finasteride was associated with a 36% reduction in risk of bladder cancer (HR: 0.64, 95% CI: 0.51-0.80; p <0.0001) among all patients. When data were stratified by race/ethnicity, finasteride use was associated with a reduction in risk of bladder cancer in White men (HR: 0.61, 95% CI: 0.43-0.86; p=0.005) and Hispanic men (HR: 0.44, 95% CI: 0.21-0.90; p=0.026), but there was no association among Black men (HR: 1.01, 95% CI: 0.67-1.51; p=0.964). CONCLUSIONS: Our study corroborates previous findings that men who are on finasteride have a lower bladder cancer incidence. However, the reduction in risk was seen only in White and Hispanic men, but not among Black men. Therefore, race/ethnicity represents an important stratification factor for future larger studies on finasteride as chemoprevention for bladder cancer.

Mandated Opioid Online Training Course-Does it Impact Opioid Prescription Patterns for Outpatient Endoscopic Urological Surgeries?

INTRODUCTION: Opioid addiction is a rising public health crisis. We evaluated if a New York State-mandated online opioid awareness course impacted our urology opioid prescription practices for outpatient endoscopic surgeries. METHODS: We completed a retrospective review of all ambulatory endoscopic cases identified by CPT codes for all adult urology faculty between February 2016 and January 2018. Patients were divided into 2 cohorts, ie pre-mandated and post-mandated training. Patient demographics, procedure details, psychiatric history and postoperative pain prescriptions were collected. Changes in opioid prescription practices prior to and after the mandated online course were reviewed. Chi-square and linear regression analyses were performed. RESULTS: A total of 356 cases were analyzed. After the training course, overall frequency of department opioid prescriptions did not change significantly (47.9% vs 47.5%, p=0.95). However, the percentage of patients receiving an oxycodone/acetaminophen prescription decreased from 90.2% to 63.0% (p <0.001) and the average number of tablets prescribed decreased (8.6 vs 16.9, p <0.001). On multivariate analysis, placement of a ureteral stent, older patient age and higher body mass index were predictors of an opioid prescription. In those patients who had a stent placed, nonopioid prescriptions increased from 42% to 88% (p <0.001). CONCLUSIONS: Overall, the New York State-mandated education session did impact opioid prescription practices for outpatient urological endoscopic surgery at our institution. The largest impact was seen within patients undergoing procedures requiring stent placement, with a decrease in total number of oxycodone/acetaminophen prescriptions and number of tablets prescribed per prescription. These data begin to demonstrate effective interventions that may impact physician practice patterns within opioid research.

Variations in Perioperative Antibiotic Prescriptions Among Academic Urologists After Ambulatory Endoscopic Urologic Surgery: Impact on Infection Rates and Validation of 2019 Best Practice Statement.

OBJECTIVE: To evaluate adherence to the American Urologic Association (AUA) best practice statement guidelines regarding antibiotic duration in the perioperative setting for endoscopic urologic surgery. We assessed concordance to these guidelines among adult urologists at a single academic institution and its correlation with postoperative positive urine cultures as it relates to the revised 2019 best practice statement. METHODS: We performed a retrospective review of all adult endoscopic ambulatory urologic surgeries performed over an 18-month period by urologists at our institution. Patient demographics, pre- and postoperative urine cultures, operative details, stent or foley use, and antibiotic prescriptions were reviewed. Chi-squared and linear regression analyses were done. RESULTS: Three hundred thirty patients were included for analysis. Sixty-two percent of patients were prescribed postoperative antibiotics, for an average of 4 days. Trimethoprim/Sulfamethoxazole and fluroquinolones were most often prescribed (43% and 38%, respectively). Intraoperative stent placement, positive urine culture within 30 days prior to surgery, and a positive urine culture within 1 year prior to surgery predicted antibiotic prescription. No significant differences were seen in rates of positive postoperative urine culture rates between cohorts that received antibiotics postoperatively vs those who did not. CONCLUSIONS: At our academic institution, we observed poor concordance with the AUA best practice statement for perioperative antibiotic prescription after ambulatory endoscopic urologic surgery. Rates of positive postoperative cultures were low and not associated with receipt or duration of antibiotic prescription at the time of surgery, supporting minimal use of antibiotics for most endoscopic cases.

Use of beta-blocker types and risk of incident prostate cancer in a multiethnic population.

PURPOSE: Increased adrenergic innervation is observed in prostate cancer (CaP) and is associated with aggressive disease. Emerging evidence suggests that beta-adrenergic blockade inhibits CaP progression. However, the association between type of beta-blocker use and risk of incident CaP on initial prostate biopsy has not been investigated in multiethnic populations. MATERIALS AND METHODS: A retrospective study of racially/ethnically diverse men (64% African-American and Hispanic), who underwent initial prostate biopsy between 2006 and 2016 in a large healthcare system was performed. Oral use of beta-blocker type was assessed by reviewing active prescriptions within the 5-year period preceding initial biopsy. Patient demographics and clinical factors were collected. RESULTS: Of 4,607 men who underwent initial prostate biopsy, 4,516 met criteria and 2,128 had a biopsy positive for CaP; 20% high-risk, 41% intermediate-risk, and 39% low or very-low risk (National Comprehensive Cancer Network classification). Overall, 15% of patients were taking a beta-blocker prior to initial biopsy, with Metoprolol, Atenolol, and Carvedilol accounting for the majority. Of beta-blocker types, Atenolol alone was associated with a 38% reduction in odds of incident CaP (P= 0.01), with a 40% and 54% reduction in risks of National Comprehensive Cancer Network intermediate and high-risk CaP (P = 0.03 and P = 0.03, respectively) compared to men not taking a beta-blocker. Furthermore, longer duration of Atenolol use (3-5 years) was associated with a 54% and 72% reduction in intermediate and high-risk disease, (P = 0.03 and P = 0.03, respectively). CONCLUSIONS: Among beta blocker types, long-term Atenolol use is associated with a significant reduction in incident CaP risk on initial prostate biopsy for clinically-significant intermediate and high-risk disease compared to men not taking a beta-blocker.

Does Glomerular Filtration Rate at Discharge After Partial Nephrectomy Predict Long-Term Glomerular Filtration Rate Stability?

Introduction: Being able to predict glomerular filtration rate (GFR) plateau after partial nephrectomy (Pnx) is an important goal in providing patients with a confident projection of maintained renal function. As such, in an ethnically and socioeconomically diverse, inner city cohort of patients undergoing Pnx, we compared preoperative (pre-op) and day of discharge (DC) GFR to that of long-term GFR measured at 12-18 months to evaluate postoperative (post-op) GFR stability. Methods: A total of 162 patients who had undergone minimally invasive Pnx at a single institution between 2010 and 2016 were reviewed. Patients with the following available measurements were included: pre-op GFR, DC GFR, and long-term GFR (12-18 months after DC). Multivariate linear regression was performed to assess factors predictive of long-term GFR, including estimated blood loss, warm ischemic time, tumor size, length of stay, pre-op GFR, DC GFR, race, chronic kidney disease, diabetes mellitus, and hypertension. Results: Mean pre-op GFR, DC GFR, and long-term GFR were 70.754, 68.326, and 66.526 mL/(minute ·1.73 m2), respectively. Mean GFR change was -4.228 pre-op to long term and -1.800 DC to long term. No significant difference was observed between means of DC GFR and long-term GFR (p = 0.248) as well as between means of pre-op GFR and DC GFR (p = 0.062). A significant difference was observed between pre-op GFR and long-term DC GFR (p = 0.002). On multivariate analysis, both pre-op GFR (ß = 0.532; 95% confidence interval [CI] = 0.256-0.808; p ≤ 0.001) and DC GFR (ß = 0.312; 95% CI = 0.089-0.537; p = 0.007) were found to be strong predictors of long-term GFR (R2 = 0.608). Conclusions: Long-term GFR in a highly ethnically diverse inner city population recovering from Pnx is stable relative to GFR measured at DC from the hospital. Our findings demonstrate that patients experience a GFR plateau after surgery, resulting in minimal change in renal function at a mean of 14 months post-op.

Does total testicular volume predict testicular volume difference in adolescent males with varicocele?

ABSTRACT Introduction: We evaluated the relationship between total testicular volume (TTV) and testicular volume differential (TVD) in adolescent males with varicocele. Both low TTV and high TVD have been independently associated with higher incidences of infertility later in life, but a predictive relationship between TTV and TVD directly has yet to be described. Materials and Methods: We retrospectively analyzed a database of Tanner 5 boys ages 16-21 who presented with varicocele at a single institution between 2009 and 2017. All patients had a scrotal sonogram prior to surgical intervention. TTV and TVD were calculated for each individual and four non-exclusive groupings of patients were created for statistical analysis. We chose 30 cc as a cut off value for low TTV based on prior studies. Results: 209 patients met our inclusion criteria. Mean age was 18.3 years (16-21, SD 1.7) with a mean total testicular volume of 36 cc (13.5-78.2, SD 11.1). Cut off points of TVD of 20% and TTV of 30 cc were used to separate patients. There were 65 boys (31%) with TTV < 30 cc and 58 boys (28%) with TVD ≥ 20%. Among males with TTV < 30 cc, 23 (35%) had a TVD ≥ 20%. Among males with TTV ≥ 30 cc, 35 (24%) had a TVD ≥ 20%. The relationship between TVD and TTV was found to be non-significant (p > 0.05). Discussion: Adolescent varicoceles continue to pose a challenge to pediatric urologists. The dilemma of over-aggressive treatment has proven difficult to balance with the risk of infertility. We hoped that elucidating the relationship between TTV and TVD could be useful in identifying patients who are at greater risk for infertility while decreasing the need for more intrusive testing, such as semen analysis, in an adolescent population. We looked at the direct relationship between low TTV and high TVD. In our population, there was a non-significant relationship between TTV < 30 cc and TVD ≥ 20% (p > 0.05) indicating that in adolescents with varicocele, TTV and TVD are independent variables. Our study limitations include the inherent user dependent bias of ultrasound measurements and data collection at a single institution with high ethnic diversity, possibly not comparable to all patient populations. Conclusions: Low TTV (< 30 cc) itself is not predictive of high TVD (≥ 20%) in adolescent boys with varicocele, despite their reported independent associations with impaired fertility in other studies.

A comparison of perinephric fat surface area and Mayo Adhesive Probability score in predicting malignancy in T1 renal masses.

INTRODUCTION: Recent studies have proposed that nearby fat deposits may have metabolic influence on kidney cancer pathobiology. Both fat quantity and quality may play unique roles in this complex relationship. As such, we investigated whether perinephric fat surface area (PFA), a quantitative measure of fat, or Mayo Adhesive Probability (MAP) score, a qualitative measure, were predictive of malignant pathology or Fuhrman grade in small renal masses. METHODS: A total of 317 patients undergoing minimally invasive partial nephrectomy between 2010 and 2016 for renal masses were retrospectively reviewed. Preoperative abdominal CT and MRI scans were measured for PFA and MAP scores. Multiple binary logistic regression models were created to identify predictive factors of malignant disease and Fuhrman grade. RESULTS: A total of 253 patients had malignant masses, while 64 had benign masses. A total of 189 of the malignant masses were T1a, while 64 were designated T1b. A total of 221 patients with malignant masses had reported Fuhrman grades. Of these 211 patients, 143 (64.7%) had low-grade and 78 (35.3%) had high-grade disease. Mean PFA was 18.0 ± 13.3 cm2, while mean MAP score was 2.6 ± 1.2. Binary logistic regression analysis yielded three variables in the best-fit model for predictors of malignant pathology: MAP score (OR = 1.374, 95% CI: 1.007-1.873, P = 0.045), male sex (OR = 2.058, 95% CI: 1.004-4.218, P = 0.049), and BMI (OR = 1.064, 95% CI: 0.998-1.135, P = 0.059). Neither MAP nor PFA was predictive of Fuhrman grade. CONCLUSIONS: MAP score, a measure of perinephric fat quality, but not PFA, a qualitative measure of fat quantity, was predictive of malignant pathology, raising the question whether fat quality rather than quantity may be involved in the pathophysiology of RCC in a large and diverse patient population. Understanding the increasing burden of obesity, further studies are needed to elaborate on these findings and to discern the exact relationship between perinephric fat deposits and renal tumorigenesis.

Does total testicular volume predict testicular volume difference in adolescent males with varicocele?

INTRODUCTION: We evaluated the relationship between total testicular volume (TTV) and testicular volume differential (TVD) in adolescent males with varicocele. Both low TTV and high TVD have been independently associated with higher incidences of infertility later in life, but a predictive relationship between TTV and TVD directly has yet to be described. MATERIALS AND METHODS: We retrospectively analyzed a database of Tanner 5 boys ages 16-21 who presented with varicocele at a single institution between 2009 and 2017. All patients had a scrotal sonogram prior to surgical intervention. TTV and TVD were calculated for each individual and four non-exclusive groupings of patients were created for statistical analysis. We chose 30 cc as a cut off value for low TTV based on prior studies. RESULTS: 209 patients met our inclusion criteria. Mean age was 18.3 years (16-21, SD 1.7) with a mean total testicular volume of 36 cc (13.5-78.2, SD 11.1). Cut off points of TVD of 20% and TTV of 30 cc were used to separate patients. There were 65 boys (31%) with TTV < 30 cc and 58 boys (28%) with TVD ≥ 20%. Among males with TTV < 30 cc, 23 (35%) had a TVD ≥ 20%. Among males with TTV ≥ 30 cc, 35 (24%) had a TVD ≥ 20%. The relationship between TVD and TTV was found to be non-significant (p > 0.05). DISCUSSION: Adolescent varicoceles continue to pose a challenge to pediatric urologists. The dilemma of over-aggressive treatment has proven difficult to balance with the risk of infertility. We hoped that elucidating the relationship between TTV and TVD could be useful in identifying patients who are at greater risk for infertility while decreasing the need for more intrusive testing, such as semen analysis, in an adolescent population. We looked at the direct relationship between low TTV and high TVD. In our population, there was a non-significant relationship between TTV < 30 cc and TVD ≥ 20% (p > 0.05) indicating that in adolescents with varicocele, TTV and TVD are independent variables. Our study limitations include the inherent user dependent bias of ultrasound measurements and data collection at a single institution with high ethnic diversity, possibly not comparable to all patient populations. CONCLUSIONS: Low TTV (< 30 cc) itself is not predictive of high TVD (≥ 20%) in adolescent boys with varicocele, despite their reported independent associations with impaired fertility in other studies.

UroLift in Place of Fiducial Markers for Patients With Benign Prostatic Hyperplasia Undergoing External Beam Radiation Therapy.

OBJECTIVE: To investigate if using a novel treatment for obstructive benign prostatic hyperplasia (UroLift) to relive lower urinary tract symptoms (LUTS) prior to external beam radiotherapy (EBRT) could also supplant the use of fiducial markers obviating the need for a second transrectal procedure while facilitating symptom-free voiding during and after EBRT a series of patients are reported on. METHODS: The medical records of 7 consecutive patients who underwent placement of UroLift for simultaneous treatment of obstructive LUTS due to benign prostatic hyperplasia and targeting of EBRT for treatment of prostate cancer between September and December of 2015 were reviewed. RESULTS: The UroLift clips were sufficiently radiopaque to make targeting possible for EBRT. All patients were able to complete a full course of radiotherapy without placement of fiducial markers. No patient experienced complications that could be attributed to the UroLift implants or procedure during their course of radiotherapy. None of the patients required additional alpha-blockers during radiation therapy. CONCLUSION: The UroLift system can serve as fiducial markers in patients undergoing EBRT. Although the current clip utilized in the UroLift system is generally radiopaque, it does not project well on the sagittal plane and would be significantly enhanced if a more strongly opaque substance was incorporated. It remains to be proven if the UroLift system can significantly reduce the symptoms of LUTS during and post EBRT.

Geographic location is an important determinant of risk factors for stone disease.

Some regions are known to have an increased burden of urolithiasis. Urolithiasis is known to be affected by weather patterns, particularly high ambient temperatures. To identify geographic differences in risk factors, we compared metabolic information for 1254 patients in two geographically distinct regions, New York and Florida, with per sample adjustment for ambient weather. We observed that patients in New York were more likely to have low urine volume, but also lower total urinary calcium (168 vs 216 mg, p = 0.005), urate (376 vs 678 mg, p < 0.001), and phosphate (0.8 vs 0.9 g, p 0.007). Temperature was a predictor of urine pH (B = -0.07, p = 0.024). Geographic region was a predictive factor (p < 0.01) for urine calcium, volume, serum bicarbonate, and anion gap. Increased anion gap and serum HCO3- were also predicted by temperature (B = 0.065, p = 0.035). Interestingly, urine volume was not affected by temperature. Our finding that temperature is a determining factor of urine pH and anion gap may help to explain the finding that hot weather is associated with increases in urolithiasis. Anion gap has also been previously associated with poor health measures and represents an interesting target for future research. Geographic location may independently contribute to urine composition, through regional diets, sun exposure, and groundwater. This study highlights the impact geographic location plays in determining risk factors for stone disease and the value of regional knowledge to the treating physician in preventing stone disease.

The Effect of Disease Severity on 24-Hour Urine Parameters in Kidney Stone Patients With Type 2 Diabetes.

OBJECTIVE: To characterize the changes in urine composition associated with increasing severity of diabetes, we analyzed urine composition relative to glycated hemoglobin (HbA1c) and treatment strategy in a largely minority population. METHODS: Patients treated for kidney stones between 2001 and 2013 at a single tertiary institution and had 24-hour urine collections were included in the study. Patients with type 1 diabetes or taking either thiazide diuretics or alkalinizing agents were excluded. Analysis was performed in IBM SPSS Statistics version 20 using multivariate regression, and Kruskal-Wallis testing was used. RESULTS: Nine hundred fifty-five patients were included in this study-268 (28%) with type 2 diabetes mellitus, of whom 53 (19.8%) used insulin. Patients with diabetes had lower urine pH, calcium, and phosphate when compared with the control group, but no significant differences were found between the diabetes groups. Multivariate analysis found that HbA1c had a positive correlation with citrate (P = .008), creatinine (P = .037), urine volume (P = .044), and a trend toward a positive association with urinary calcium calcium (P = .064). Insulin use did not have a significant relationship with urinary parameters but trended toward an inverse relationship with calcium (P = .051). pH was not a significant predictor of any urine constituent. CONCLUSION: In an ethnically diverse inner city patient population, patients with diabetes mellitus type 2 who use insulin have no significant differences in urine parameters when compared with those on oral hypoglycemics. Worsening glucose control as measured by HbA1c levels predicts increased urine citrate and volume.

The visceral fat compartment is independently associated with changes in urine constituent excretion in a stone forming population.

The objective of this study was to identify the independent effect of visceral fat on urine constituent excretion in a stone forming population. Using a database of 382 kidney stone patients with available visceral fat quantification, we created multiple linear regression models predicting changes in urinary solutes based on visceral fat area and body mass-index, divided by gender. Chi-square tests were used to compare stone composition by body mass-index and visceral fat area. Visceral fat predicts increases in urinary creatinine, sodium, and volume in men, but only urinary phosphate in women. In women, total body mass-index does not appear to modify this effect, but in men it is more pronounced in overweight patients for creatinine and volume only. Elevated visceral fat is associated with increased probability of uric acid stone composition. Different fat compartments likely effect urine composition in different ways. This effect appears to be different in men and women. Understanding and quantifying the effects of different fat compartments is probably important to understanding the metabolism of urolithiasis.

Prevalence of and attitudes about distracted driving in college students.

OBJECTIVE: To identify current distracted driving (DD) behaviors among college students, primarily those involving cell phone use, and elucidate the opinions of the students on the most effective deterrent or intervention for reducing cell phone use. METHODS: Students enrolled at 12 colleges and universities were recruited to participate in an online, anonymous survey. Recruitment was done via school-based list-serves and posters. School sizes ranged from 476 to over 30,000. The validated survey included 38 questions; 17 were specifically related to distracted driving. RESULTS: Four thousand nine hundred sixty-four participants completed the surveys; the average age was 21.8, 66% were female, 82.7% were undergraduates, and 47% were white/non-Hispanic. Additionally, 4,517 (91%) reported phoning and/or texting while driving; 4,467 (90%) of drivers said they talk on the phone while driving; 1,241 (25%) reported using a hands-free device "most of the time"; 4,467 (90%) of drivers reported texting while driving; 2,488 (50%) reported sending texts while driving on the freeway; 2,978 (60%) while in stop-and-go traffic or on city streets; and 4,319 (87%) at traffic lights. Those who drove more often were more likely to drive distracted. When asked about their capability to drive distracted, 46% said they were capable or very capable of talking on a cell phone and driving, but they felt that only 8.5% of other drivers were capable. In a multivariate model, 9 predictors explained 44% of the variance in DD, which was statistically significant, F (17, 4945) = 224.31; P <.0001; R(2) = 0.44. The four strongest predictors (excluding driving frequency) were self-efficacy (i.e., confidence) in driving while multitasking (ß = 0.37), perception of safety of multitasking while driving (ß = 0.19), social norms (i.e., observing others multitasking while driving; ß = 0.29), and having a history of crashing due to multitasking while driving (ß = 0.11). CONCLUSIONS: Distracted driving is a highly prevalent behavior among college students who have higher confidence in their own driving skills and ability to multitask than they have in other drivers' abilities. Drivers' self-efficacy for driving and multitasking in the car, coupled with a greater likelihood of having witnessed DD behaviors in others, greatly increased the probability that a student would engage in DD. Most students felt that policies, such as laws impacting driving privilege and insurance rate increases, would influence their behavior.