Purpose — To examine temporal changes in the demographics of patients undergoing definitive treatment for kidney stones over a 20-year period in Ontario, Canada.
Methods — Using the Ontario Health Insurance Plan physician claims database and the Canadian Institute for Health Information Discharge Abstract Database the authors conducted a population-based cross-sectional time series analysis by identifying all kidney stone treatments performed between July 1, 1991-December 31, 2010. The demographics assessed were gender, age and socioeconomic status. The rate and/or proportion of kidney stone treatments per strata of the aforementioned demographics were calculated for every one-year block of the study period. Time series analysis with exponential smoothing and autoregressive integrated moving average models were used to assess for trends over time.
Results — The authors identified 116,115 patients who had undergone treatment for kidney stones during the study period. The rate of stone procedures performed per year increased steadily from 85/100,000 to 126/100,000. Over time, the rate of females treated increased significantly (40/100,000 to 53/100,000, p<0.0001). Conversely, the rate of men treated remained stable (82/100,000 to 83/100,000, p=0.11). Considering age, the rate of patients >64 years old increased significantly over time (67/100,000 to 89/100,000, p<0.0001). Considering socioeconomic status, approximately 20% of patients fell into each of the five income quintiles, over the entire study period.
Conclusions — Our population-based study demonstrates an increased rate of both females and patients >64 years old undergoing definitive treatment for kidney stones over time.
Kidney and urinary tract disorders