Exploring the Association of Asthma with Urinary Stone Disease: Results from the National Health and Nutrition Examination Survey 2007-2014.

Background: The prevalence of urinary stone disease (USD) and asthma is rising and has recently been associated in a pediatric population.
Objective: To investigate the association between asthma and USD in a nationally representative adult population.
Design, Setting, and Participants: We analyzed the National Health and Nutrition Examination Survey 2007-2014, a US population-based cross-sectional study. A history of asthma and USD was obtained by self-report to questionnaires. USD severity was represented by graded stratification into non-stone formers, single stone formers, and recurrent stone formers (>2 stones).
Outcome Measurements and Statistical Analysis: Odds ratios (ORs) for asthma were calculated for respondents with USD and separately for the graded USD groups. Survey-weighted logistic regression models included adjustments for demographics (model A), medical information (model B), and for relevant medications (model C).
Results and Limitations: A total of 20 906 participants aged ≥20 yr were included in the analysis. Of these, 9.2% reported of having a history of kidney stones. Logistic regression analysis adjusted for demographics, medical conditions, and medications showed that stone formers had significantly increased odds of asthma (odds ratio=1.23; 95% confidence interval: 1.03-1.47; p=0.023). Separate logistic regression analysis demonstrated a graded association between single and recurrent stone formers and the odds of having asthma (p=0.01), which remained significant in the 20-50-yr-old population and the diabetic population, especially for recurrent stone formers. Causal relationships were limited by cross-sectional nature of the study.
Conclusions: Increasing severity of USD is associated with an increase in odds for asthma among American adults, providing impetus for future studies into the mechanisms explaining this phenomenon.
Patient Summary: In this report, we looked at self-reported histories of asthma and urinary stone disease (USD) using information from a large US population. We found that asthma was associated with USD; however, further studies are needed to elucidate this relationship.
(Copyright © 2018 European Association of Urology. Published by Elsevier B.V. All rights reserved.)