Association of bone mineral density with incidental renal stone in long-term survivors of childhood acute lymphoblastic leukemia.

PURPOSE: Our objective was to evaluate the association between low bone mineral density (BMD) and incidental renal stones among long-term survivors of childhood acute lymphoblastic leukemia (ALL).

METHODS

Adult participants who were 10+ years from their childhood ALL diagnosis and members of the St. Jude Lifetime Cohort study were recruited between December 2007 and March 2011. During their risk-based medical evaluations, they underwent quantitative computed tomography (QCT) to evaluate BMD. Incidental renal stones were identified by radiologists' review of axial QCT source images. Demographic and dietary information were abstracted from health surveys and the Block Food Frequency questionnaire, respectively. The multivariable logistic regression model was used for analysis.

RESULTS

At a median of 26.1 years from diagnosis, BMD Z scores were ≤-2 in 34 of 662 (5.2 %) and renal stones detected in 73 of 662 (11 %) participants. Adjusted for age, renal radiation, dietary vitamin D, gender, and body mass index, when compared to those with BMD Z scores ≥0, the risk of renal stones was increased among those with BMD Z scores ≤-2 (odds ratio [OR], 2.92; 95 % confidence interval [CI] 1.14-7.48). Risk of renal stones significantly increased for older age (45-54 vs.18-24 years; OR, 3.70; 95 % CI 1.11-12.35) whereas the risk was higher but nonsignificant for >141.5 IU (sample median) daily intake of vitamin D (OR, 1.64; 95 % CI 0.98-2.75).

CONCLUSIONS AND IMPLICATIONS FOR CANCER SURVIVORS: Older ALL survivors with BMD Z scores ≤-2 are at risk for renal stones and should be counseled so that appropriate follow-up care can be provided for those among whom renal stones are detected.