UPJ INSIGHT Barriers to Preventive Pharmacological Therapy Use in Older Patients With Urinary Stone Disease

By: Noah Krampe, MD, University of Michigan Medical School, Ann Arbor; Mary K. Oerline, MS, University of Michigan Medical School, Ann Arbor; Ryan S. Hsi, MD, Vanderbilt University Medical Center, Nashville, Tennessee; Joseph J. Crivelli, MD, University of Alabama at Birmingham Heersink School of Medicine; John R. Asplin, MD, Litholink Corporation, Laboratory Corporation of America Holdings, Itasca, Illinois; Vahakn B. Shahinian, MD, University of Michigan Medical School, Ann Arbor; John M. Hollingsworth, MD, MS, University of Michigan Medical School, Ann Arbor, NorthShore University HealthSystem, Evanston, Illinois | Posted on: 19 Jan 2024

Krampe N, Oerline MK, Hsi RS, et al. Understanding the barriers to preventive pharmacological therapy use in older patients with urinary stone disease. Urol Pract. 2024;11(1):218-225.

Study Need and Importance

Despite compelling clinical trial evidence and professional society guideline recommendations, prescription rates of preventative pharmacological therapy (PPT) for urinary stone disease are low. We sought to understand how patient- and clinician-level factors contribute to the decision to prescribe PPT after an index stone event.

What We Found

Of the 11,563 patients meeting inclusion criteria, 33.6% were prescribed PPT. There was nearly sevenfold variation between the treating clinician with the lowest prescription rate (11%) and the one with the highest (75%; Figure). Nineteen percent of this variation was attributable to clinician factors. After accounting for measured patient differences and clinician volume, patients had twice the odds of being prescribed PPT if they were treated by a nephrologist (OR, 2.15; 95% CI, 1.79-2.57) or a primary care physician (OR, 1.78; 95% CI, 1.22-2.58) compared to being treated by a urologist.

Figure. Adjusted rates of preventative pharmacological therapy (PPT) prescription by individual treating clinician. Caterpillar plot of adjusted PPT prescription rate for each individual physician (orange dots that form a curved line), with 95% confidence intervals (in dark gray), ordered from lowest to highest. Rates of PPT prescription were adjusted for all covariates in the model. They include age, sex, race, region, urbanicity, dual eligibility status, hierarchical condition category score, high recurrence risk categories, an indicator for more than one abnormality, 24-hour urine collection factors, physician specialty, and physician patient volume (continuous). For each physician, it is a marker (ie, orange dot) at the adjusted PPT prescription rate for the physician with 95% confidence intervals.

Limitations

While our study population was based on identifying patients with incident stone episodes who had a documented urine chemistry abnormality on their initial urine collection, we cannot exclude the possibility of persistent systematic differences between the subpopulations of patients cared for by urologists vs primary care physicians and nephrologists, which could have influenced the decision to prescribe PPT. Second, potential misclassification bias exists because some forms of alkali therapy are available over the counter, but we have no way of knowing whether they were prescribed. Third, we analyzed a large convenience sample of mostly older adults, which could limit our study’s external validity.

Interpretation for Patient Care

These study findings help shed light on the low use of PPT in the medical community and reveal that the clinician who cares for a patient with urinary stone disease is an important determinant of whether the patient will be prescribed PPT.