Predictive Factors for Kidney Stone Recurrence in Type 2 Diabetes Mellitus

To determine the predictive factors for kidney stone recurrence in type 2 diabetic patients.

A retrospective cohort study was conducted from 2013 to 2019 by using the database of diabetic patients diagnosed with kidney stone disease. The patients were divided into 2 groups according to stone disease status: recurrent stone and nonrecurrent stone. Baseline characteristics were compared and logistic regression was done to assess which variables could predict a stone recurrence.

There were 1617 type 2 diabetic patients with kidney stone disease, 1244 (77%) did not have a stone recurrence and 373 (23%) had a stone recurrence. Of these patients with recurrent stone, 40% had asymptomatic stones, 43% visited emergency department, and 45% required a surgical intervention. Median time to recurrence was 64 months. Multivariable analysis revealed that body mass index (odds ratios [OR] 1.032, 95% confidence interval [CI] 1.016-1.047), urine pH (OR 0.500, CI 0.043-0.581), HbA1c (OR 1.186, CI 1.012-1.277), diabetic neuropathy (OR 1.839, CI 1.413-2.392), diabetic retinopathy (OR 1.690, CI 1.122-2.546), insulin as well as potassium citrate therapy (OR 0.611, CI 0.426-0.87), and stone with calcium oxalate and uric acid composition (OR 1.955, CI 1.420-2.691 and OR 2.221, CI 1.249-3.949, respectively) are significant predictors for stone recurrence.

The severity of diabetes and stone composition are strong predictors for stone recurrence in type 2 diabetic patients, while HbA1c and urine pH are important modifiable factors.