Charles D. Scales

Prevalence of Kidney Stones in the United States

BACKGROUND The last nationally representative assessment of kidney stone prevalence in the United States occurred in 1994. After a 13-yr hiatus, the National Health and Nutrition Examination Survey (NHANES) reinitiated data collection regarding kidney stone history. OBJECTIVE Describe the current prevalence of stone disease in the United States, and identify factors associated with a history of kidney stones. DESIGN, SETTING, AND PARTICIPANTS A cross-sectional analysis of responses to the 2007-2010 NHANES (n=12 110). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Self-reported history of kidney stones. Percent prevalence was calculated and multivariable models were used to identify factors associated with a history of kidney stones. RESULTS AND LIMITATIONS The prevalence of kidney stones was 8.8% (95% confidence interval [CI], 8.1-9.5). Among men, the prevalence of stones was 10.6% (95% CI, 9.4-11.9), compared with 7.1% (95% CI, 6.4-7.8) among women. Kidney stones were more common among obese than normal-weight individuals (11.2% [95% CI, 10.0-12.3] compared with 6.1% [95% CI, 4.8-7.4], respectively; p<0.001). Black, non-Hispanic and Hispanic individuals were less likely to report a history of stone disease than were white, non-Hispanic individuals (black, non-Hispanic: odds ratio [OR]: 0.37 [95% CI, 0.28-0.49], p<0.001; Hispanic: OR: 0.60 [95% CI, 0.49-0.73], p<0.001). Obesity and diabetes were strongly associated with a history of kidney stones in multivariable models. The cross-sectional survey design limits causal inference regarding potential risk factors for kidney stones. CONCLUSIONS Kidney stones affect approximately 1 in 11 people in the United States. These data represent a marked increase in stone disease compared with the NHANES III cohort, particularly in black, non-Hispanic and Hispanic individuals. Diet and lifestyle factors likely play an important role in the changing epidemiology of kidney stones.

Radiation Exposure in the Acute and Short-Term Management of Urolithiasis at 2 Academic Centers

PURPOSE Diagnostic imaging has a central role in the evaluation and management of urolithiasis. A variety of modalities are available, each with benefits and limitations. Without careful consideration of imaging modalities in quantity and type patients may receive excessive doses of radiation during initial diagnostic and followup evaluations. Therefore, we determined the effective radiation dose associated with an acute stone episode and short-term followup. MATERIALS AND METHODS A multicenter retrospective study of all patients who presented with an acute stone episode was performed. The analysis included all imaging studies related to stone disease performed within 1 year of the acute event. Using accepted effective radiation dose standards for each of these examinations, the total radiation dose administered was calculated and compared by patient characteristics including stone location, stone number and intervention strategy. The primary outcome assessed was a total radiation dose greater than 50 mSv, the recommended yearly dose limit for occupational exposure by the International Commission on Radiological Protection. RESULTS We identified 108 patients who presented to our respective institutions with a primary acute stone episode between 2000 and 2006. The mean age in our cohort was 48.6 years and 50% of the patients were men. Patients underwent an average of 4 radiographic examinations during the 1-year period. Studies performed included a mean of 1.2 plain abdominal films of the kidneys, ureters and bladder (range 0 to 7), 1.7 abdominopelvic computerized tomograms (range 0 to 6) and 1 excretory urogram (range 0 to 3) during the first year of followup. The median total effective radiation dose per patient was 29.7 mSv (IQR 24.2, 45.1). There were 22 (20%) patients who received greater than 50 mSv. Analysis of stone location, number of stones, stone composition, patient age, sex and surgical intervention indicated no statistically significant difference in the probability of receiving a total radiation dose greater than 50 mSv. CONCLUSIONS A fifth of patients receive potentially significant radiation doses in the short-term followup of an acute stone event. Radiographic imaging remains an integral part of the diagnosis and management of symptomatic urolithiasis. While debate exists regarding the threshold level for radiation induced fatal malignancies, urologists must be cognizant of the radiation exposure to patients, and seek alternative imaging strategies to minimize radiation dose during acute and long-term stone management.

Cost comparison among robotic, laparoscopic, and open hysterectomy for endometrial cancer.

OBJECTIVE: To use decision modeling to compare the costs associated with robotic, laparoscopic, and open hysterectomy for the treatment of endometrial cancer. METHODS: Three separate models were used, each with sensitivity analysis: 1) a societal perspective model, which included inpatient hospital costs, robotic expenses, and lost wages and caregiver costs; 2) a hospital perspective plus robot costs model, which was identical to the societal perspective model but excluded lost wages and caregiver costs; and 3) a hospital perspective without robot costs model, which was identical to the hospital perspective plus robot costs model except that it excluded initial cost of the robot. RESULTS: The societal perspective model predicted laparoscopy (

NCCN Guidelines Insights: Prostate Cancer Early Detection, Version 2.2016

10,128) as the least expensive approach followed by robotic and (

Practice variation in the surgical management of urinary lithiasis

11,476) and open hysterectomy (

Evaluating Outcomes of Enterocystoplasty in Patients With Spina Bifida: A Review of the Literature

12,847). Societal perspective model sensitivity analyses predicted robotic hysterectomy to be least expensive when robotic disposable equipment cost less than

Impact of Long-Term Potassium Citrate Therapy on Urinary Profiles and Recurrent Stone Formation

1,046 per case (baseline cost

Reporting of Harm in Randomized Controlled Trials Published in the Urological Literature

2,394). In the hospital perspective plus robot costs model, laparoscopy was least expensive (

Changes in Initial Treatment for Prostate Cancer Among Medicare Beneficiaries, 1999–2007

6,581) followed by open (

The impact of unplanned postprocedure visits in the management of patients with urinary stones

7,009) and robotic hysterectomy (