Kidney Stone Events Following Parathyroidectomy vs Nonoperative Management for Primary Hyperparathyroidism.

CONTEXT: Primary hyperparathyroidism (PHPT) is associated with an increased risk of kidney stones. Few studies account for PHPT severity or stone risk when comparing stone events after parathyroidectomy vs nonoperative management. OBJECTIVE: Compare the incidence of kidney stone events in PHPT patients treated with parathyroidectomy vs nonoperative management. DESIGN: Longitudinal cohort study with propensity score inverse probability weighting and multivariable Cox proportional hazards regression. SETTING: Veterans Health Administration integrated health care system. PATIENTS: A total of 44 978 patients with > 2 years follow-up after PHPT diagnosis (2000-2018); 5244 patients (11.7%) were treated with parathyroidectomy. MAIN OUTCOMES MEASURE: Clinically significant kidney stone event. RESULTS: The cohort had a mean age of 66.0 years, was 87.8% male, and 66.4% White. Patients treated with parathyroidectomy had higher mean serum calcium (11.2 vs 10.8mg/dL) and were more likely to have a history of kidney stone events. Among patients with baseline history of kidney stones, the unadjusted incidence of ≥ 1 kidney stone event was 30.5% in patients managed with parathyroidectomy (mean follow-up, 5.6 years) compared with 18.0% in those managed nonoperatively (mean follow-up, 5.0 years). Patients treated with parathyroidectomy had a higher adjusted hazard of recurrent kidney stone events (hazard ratio [HR], 1.98; 95% CI, 1.56-2.51); however, this association declined over time (parathyroidectomy × time: HR, 0.80; 95% CI, 0.73-0.87). CONCLUSION: In this predominantly male cohort with PHPT, patients treated with parathyroidectomy continued to be at higher risk of kidney stone events in the immediate years after treatment than patients managed nonoperatively, although the adjusted risk of stone events declined with time, suggesting a benefit to surgical treatment.

The Urine Albumin-to-Creatinine Ratio and Kidney Function after Nephrectomy.

PURPOSE: Patients with kidney cancer are at risk for chronic kidney disease after radical and partial nephrectomy. We determined if the urine albumin-to-creatinine ratio is independently associated with progressive chronic kidney disease after nephrectomy. MATERIALS AND METHODS: We performed a cohort study based within a large, integrated health care system. We identified patients who underwent radical or partial nephrectomy from 2004 to 2014 with urine albumin-to-creatinine ratio measured in the 12 months before surgery. We fit multivariable models to determine if the urine albumin-to-creatinine ratio was associated with the time to chronic kidney disease progression (defined as reaching stage 4 or 5 chronic kidney disease, estimated glomerular filtration rate less than 30 ml/minute/1.73 m2). We performed a parallel analysis measuring the time to stage 3b, 4 or 5 chronic kidney disease (estimated glomerular filtration rate less than 45 ml/minute/1.73 m2) among patients with normal or near normal preoperative kidney function (estimated glomerular filtration rate 60 ml/minute/1.73 m2 or greater). We also examined the association between urine albumin-to-creatinine ratio and survival. RESULTS: A total of 1,930 patients underwent radical or partial nephrectomy and had preoperative urine albumin-to-creatinine ratio and preoperative and postoperative estimated glomerular filtration rate. Of these patients 658 (34%) and 157 (8%) had moderate (urine albumin-to-creatinine ratio 30 to 300 mg/gm) or severe albuminuria (urine albumin-to-creatinine ratio greater than 300 mg/gm), respectively. Albuminuria severity was independently associated with progressive chronic kidney disease after radical (moderate albuminuria HR 1.7, 95% CI 1.4-2.2; severe albuminuria HR 2.3, 95% CI 1.7-3.1) and partial nephrectomy (moderate albuminuria HR 1.8, 95% CI 1.2-2.7; severe albuminuria HR 4.3, 95% CI 2.7-7.0). Albuminuria was also associated with survival following radical and partial nephrectomy. CONCLUSIONS: In patients undergoing radical or partial nephrectomy the severity of albuminuria can stratify risk of progressive chronic kidney disease.

Prevalence of twenty-four hour urine testing in Veterans with urinary stone disease.

OBJECTIVE: The American Urological Association guidelines recommend 24-hour urine testing in patients with urinary stone disease to decrease the risk of stone recurrence; however, national practice patterns for 24-hour urine testing are not well characterized. Our objective is to determine the prevalence of 24-hour urine testing in patients with urinary stone disease in the Veterans Health Administration and examine patient-specific and facility-level factors associated with 24-hour urine testing. Identifying variations in clinical practice can inform future quality improvement efforts in the management of urinary stone disease in integrated healthcare systems. MATERIALS AND METHODS: We accessed national Veterans Health Administration data through the Corporate Data Warehouse (CDW), hosted by the Veterans Affairs Informatics and Computing Infrastructure (VINCI), to identify patients with urinary stone disease. We defined stone formers as Veterans with one inpatient ICD-9 code for kidney or ureteral stones, two or more outpatient ICD-9 codes for kidney or ureteral stones, or one or more CPT codes for kidney or ureteral stone procedures from 2007 through 2013. We defined a 24-hour urine test as a 24-hour collection for calcium, oxalate, citrate or sulfate. We used multivariable regression to assess demographic, geographic, and selected clinical factors associated with 24-hour urine testing. RESULTS: We identified 130,489 Veterans with urinary stone disease; 19,288 (14.8%) underwent 24-hour urine testing. Patients who completed 24-hour urine testing were younger, had fewer comorbidities, and were more likely to be White. Utilization of 24-hour urine testing varied widely by geography and facility, the latter ranging from 1 to 40%. CONCLUSIONS: Fewer than one in six patients with urinary stone disease complete 24-hour urine testing in the Veterans Health Administration. In addition, utilization of 24-hour urine testing varies widely by facility identifying a target area for improvement in the care of patients with urinary stone disease. Future efforts to increase utilization of 24-hour urine testing and improve clinician awareness of targeted approaches to stone prevention may be warranted to reduce the morbidity and cost of urinary stone disease.

Contemporary Use of Partial Nephrectomy: Are Older Patients With Impaired Kidney Function Being Left Behind?

OBJECTIVE: To assess whether patient factors, such as age and preoperative kidney function, were associated with receipt of partial nephrectomy in a national integrated healthcare system. MATERIALS AND METHODS: We identified patients treated with a radical or partial nephrectomy from 2002 to 2014 in the Veterans Health Administration. We examined associations among patient age, sex, race or ethnicity, multimorbidity, baseline kidney function, tumor characteristics, and receipt of partial nephrectomy. We estimated the odds of receiving a partial nephrectomy and assessed interactions between covariates and the year of surgery to explore whether patient factors associated with partial nephrectomy changed over time. RESULTS: In our cohort of 14,186 patients, 4508 (31.2%) received a partial nephrectomy. Use of partial nephrectomy increased from 17% in 2002 to 32% in 2008 and to 38% in 2014. Patient race or ethnicity, age, tumor stage, and year of surgery were independently associated with receipt of partial nephrectomy. Black veterans had significantly increased odds of receipt of partial nephrectomy, whereas older patients had significantly reduced odds. Partial nephrectomy utilization increased for all groups over time, but older patients and patients with worse baseline kidney function showed the least increase in odds of partial nephrectomy. CONCLUSION: Although the utilization of partial nephrectomy increased for all groups, the greatest increase occurred in the youngest patients and those with the highest baseline kidney function. These trends warrant further investigation to ensure that patients at the highest risk of impaired kidney function are considered for partial nephrectomy whenever possible.

Phase II study of pomegranate juice for men with rising prostate-specific antigen following surgery or radiation for prostate cancer.

PURPOSE: Phytochemicals in plants may have cancer preventive benefits through antioxidation and via gene-nutrient interactions. We sought to determine the effects of pomegranate juice (a major source of antioxidants) consumption on prostate-specific antigen (PSA) progression in men with a rising PSA following primary therapy. EXPERIMENTAL DESIGN: A phase II, Simon two-stage clinical trial for men with rising PSA after surgery or radiotherapy was conducted. Eligible patients had a detectable PSA > 0.2 and < 5 ng/mL and Gleason score < or = 7. Patients were treated with 8 ounces of pomegranate juice daily (Wonderful variety, 570 mg total polyphenol gallic acid equivalents) until disease progression. Clinical end points included safety and effect on serum PSA, serum-induced proliferation and apoptosis of LNCaP cells, serum lipid peroxidation, and serum nitric oxide levels. RESULTS: The study was fully accrued after efficacy criteria were met. There were no serious adverse events reported and the treatment was well tolerated. Mean PSA doubling time significantly increased with treatment from a mean of 15 months at baseline to 54 months posttreatment (P < 0.001). In vitro assays comparing pretreatment and posttreatment patient serum on the growth of LNCaP showed a 12% decrease in cell proliferation and a 17% increase in apoptosis (P = 0.0048 and 0.0004, respectively), a 23% increase in serum nitric oxide (P = 0.0085), and significant (P < 0.02) reductions in oxidative state and sensitivity to oxidation of serum lipids after versus before pomegranate juice consumption. CONCLUSIONS: We report the first clinical trial of pomegranate juice in patients with prostate cancer. The statistically significant prolongation of PSA doubling time, coupled with corresponding laboratory effects on prostate cancer in vitro cell proliferation and apoptosis as well as oxidative stress, warrant further testing in a placebo-controlled study.

Prevention of bladder cancer: a review.

INTRODUCTION: Bladder cancer represents an ideal tumor model to test and apply cancer prevention strategies. In addition to reviewing the epidemiology of transitional cell carcinoma (TCC), we review the current status and the future directions of bladder cancer prevention. MATERIALS AND METHODS: A literature review of peer-reviewed articles which address bladder cancer prevention was performed. RESULTS: Pre-clinical and limited clinical data suggest that bladder cancer is responsive to efforts to delay or prevent its development in at-risk patients, and in reducing the risk of recurrence in patients with established disease. Many epidemiologic studies, however, investigating natural products, such as vitamins and herbal compounds, lack conclusive evidence of their chemopreventive effects. CONCLUSIONS: While many agents hold promise in the prevention of bladder cancer, none currently can be recommended as proven chemoprevention strategies. Improving the accuracy of patient risk assessment and identification of surrogate endpoint biomarkers are crucial to the testing of these strategies. Efficient study design will ensure rapid and substantial advances in the chemoprevention of bladder cancer.