Changing trends in the treatment of nephrolithiasis in the real world

INTRODUCTION: Changes in the surgical treatment of nephrolithiasis, owing to recent technical advances and innovations, have made treatments more effective and less invasive. In this retrospective, observational cohort study, we identified the changing trends in the treatment of nephrolithiasis. MATERIALS AND METHODS: We included patients with newly diagnosed nephrolithiasis who received any treatment in the United States, including extracorporeal shockwave lithotripsy (SWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), and open surgery, from January 2007 to December 2014. Demographic factors, such as age, sex, region, surgical treatment type, and cost data, were analyzed. RESULTS: The median age of patients at treatment was 52 years, and the ratio of men and women was similar. There were definite changes in the trends of all treatment modalities (p < 0.01). Both the number and percentage tended to increase for RIRS, whereas for SWL, the number increased, but the percentage showed a steady decrease. In PCNL, both number and percentage increased to a minor degree. The overall cost of nephrolithiasis treatments during the study period nearly doubled (from $30,998,726 to $57,310,956). The number of treatments and average cost per treatment increased annually for each treatment modality. RIRS was the least expensive; the other procedures in decreasing order of their mean costs were as follows: SWL, PCNL, and open surgery. CONCLUSIONS: There was a gradual but constant change in treatment trends of nephrolithiasis, with an increasing trend for RIRS and a decreasing trend for SWL. Although PCNL has relatively invasive characteristics, it is still in steady demand.