Association of urolithiasis with systemic conditions among pediatric patients at children's hospitals

Abstract

Purpose: Urolithiasis is associated with systemic medical conditions in adults but associations have not been well studied in children. We investigated the association of urolithiasis with diabetes mellitus, hypertension and obesity among children with and without urolithiasis.

Materials and methods: We performed a matched case-control study using the PHIS (Pediatric Health Information System) database. ICD-9 codes identified urolithiasis cases from 2004 to 2009. Four randomly selected controls were matched by age, hospital, patient care setting and year of treatment. Diagnoses from all hospital encounters were ascertained for comorbid conditions. Univariate and multivariable conditional logistic regression was used to assess the associations of urolithiasis with diabetes mellitus, hypertension and obesity.

Results: We identified 9,843 urolithiasis cases and 39,047 controls. On univariate analysis stone formers had significantly higher odds of obesity (OR 1.44, 95% CI 1.27-1.64) and hypertension (OR 2.12, 95% CI 1.88-2.40) compared to controls. The odds of type I diabetes mellitus was lower among cases compared to controls (OR 0.38, 95% CI 0.30-0.48). After adjusting for gender, race, insurance type and number of visits using logistic regression, children with urolithiasis still had higher odds of obesity (AOR 1.30, 95% CI 1.12-1.51) and hypertension (AOR 1.61, 95% CI 1.40-1.86) as well as lower odds of type I diabetes mellitus (AOR 0.32, 95% CI 0.25-0.41) compared to controls.

Conclusions: Among pediatric patients at freestanding children's hospitals, urolithiasis is associated with higher odds of obesity and hypertension and lower odds of type I diabetes mellitus. These findings may be helpful in further elucidating the etiology of pediatric urolithiasis.