Geographic Variation in the Quality of Secondary Prevention for Nephrolithiasis

OBJECTIVE - To examine the variation in the quality of secondary prevention for nephrolithiasis across health care markets.

METHODS - Using analytical files from Litholink Corporation (2003-2012), we identified adults with nephrolithiasis and abnormal urine biochemistries on 24-hour urine collection. After assigning all patients to a hospital referral region (HRR), we determined the proportion of patients in each HRR who underwent on-treatment follow-up testing (our measure of quality). We then fitted multivariate hierarchical regression models to quantify the amount of variation in this proportion across HRRs. Finally, we examined for associations between a patient's odds of on-treatment follow-up testing and the supply of primary care and specialist physicians in an HRR.

RESULTS - The mean rate on-treatment follow-up testing was exceedingly low at only 11.9%. This rate has been stable over time. There was fourfold variation in this rate across HRRs from as little as 6.6% to as high as 23.4%. Those HRRs with higher on-treatment follow-up testing rates tended to have a wealthier and more educated population (P = .01). Receipt of on-treatment follow-up testing was not associated with the number of specialists per capita.

CONCLUSION - Wide geographic variation exists in the quality of secondary prevention for patients with nephrolithiasis. Given that current guidelines recommend on-treatment follow-up testing, efforts to increase its uptake are needed.

Urology. 2015 Jun 11. pii: S0090-4295(15)00551-8. doi: 10.1016/j.urology.2015.05.022. [Epub ahead of print]

Alruwaily AF1, Dauw CA2, Bierlein MJ2, Asplin JR3, Ghani KR2, Wolf JS Jr2, Hollingsworth JM4.

1 Divisions of Endourology and Health Services Research, Department of Urology, University of Michigan, Ann Arbor, MI; Department of Surgery, College of Medicine, Al-Imam Muhammad Ibn Saud Islamic University (IMSIU), Riyadh, Saudi Arabia.
2 Divisions of Endourology and Health Services Research, Department of Urology, University of Michigan, Ann Arbor, MI.
3 Litholink Corporation, Laboratory Corporation of America Holdings, Chicago, IL.
4 Divisions of Endourology and Health Services Research, Department of Urology, University of Michigan, Ann Arbor, MI.