Substantially more new cases of kidney stones than anticipated are occurring in the United States, according to nationally representative estimates.
Investigators led by Jonathan E. Shoag, MD, of University Hospitals Cleveland Medical Center, Case Western Reserve University in Cleveland, Ohio, analyzed data from 10,521 individuals aged 20 years or older who responded to a National Health and Nutrition Examination Survey (NHANES) from 2015 to 2018. Participants were asked “In the past 12 months, have you passed a kidney stone?” and “Have you ever had a kidney stone?”
The rate of passing a symptomatic kidney stone in the last 12 months was 2.1% or 2054 stones per 100,000 adults, the investigators reported in The Journal of Urology. That incidence rate is much higher than previous reports, and it does not include asymptomatic stones. In addition, 11.0% of participants reported ever having a kidney stone.
“Our findings have significant implications,” Dr Shoag’s team wrote. “If these findings are due to a persistent increase in stone incidence over recent years, and this trend continues, there is the potential need for substantially increased resource utilization. This would mean an increase in the number of emergency department visits, urologic consults, and the need for interventions such as lithotripsy or placement of stents.”
Further, this study underscores the critical need to learn what is driving these trends, as well as the importance of dietary and pharmacologic efforts to preventing stone recurrence, according to the investigators.
In multivariate Poisson regression analyses, hypertension and high cholesterol were significantly associated with 79% and 24% increased risks of passing a symptomatic kidney stone in the past 12 months, respectively. Compared with White adults, Hispanic, Black, and Asian adults had significant 44%, 68%, and 41% lower risks of passing a kidney stone within the past 12 months, respectively. According to the investigators, historical risk factors for stone prevalence may play less of a role in stone incidence.
The risk of ever having a kidney stone significantly increased 1.4- to more than 2-fold with age categories older than 20-29 years. Compared with White adults, Hispanic, Black, and Asian adults had significant 24%, 48%, and 49% lower risks for stone history, respectively. Adults in the overweight and obese categories of body mass index (BMI, 25-29.9 and 30 kg/m2 or higher, respectively) had a significant 26% and 44% increased risk for ever having a stone compared with those who had a BMI of 18.5-24.9 kg/m2. Women had a significant 17% decreased risk for a history of stones compared with men.
Hill AJ, Basourakos SP, Lewicki P, et al. Incidence of kidney stones in the United States, the continuous National Health and Nutrition Examination Survey. J Urol. Published online December 2, 2021. doi:10.1097/JU.0000000000002331