Preventive pharmacological therapy for kidney stones
Reviewed by Xi Cheng

Kidney stones are common, painful and are a chronic disease with a high lifetime risk of recurrence. Without treatment 35-50% of patients experience a second stone within five years of their first experience. Thiazide diuretics, alkali citrate treatment and allopurinol have been used as preventive pharmacological therapy. Trials have found preventive pharmacological therapy to reduce recurrence rates by 72-81%, however these trials are carried out in idealised conditions and do not consider real-life problems such as adherence to treatment. In this study, the authors compare the adherence rates to medication and clinical health outcomes (emergency department visits, hospitalisations and surgery). Adults aged between 18 and 64 years old with a diagnosis of kidney stone disease, identified using physician codes between 2002 and 2006, were included. National Drug Codes were used to track preventive pharmacological therapy agent prescriptions within 180 days of stone claim. To be included patients also needed to have health insurance 180 days before their index stone claim and two years post their first prescription. Overall, 8890 patients were identified using preventive pharmacological therapy with kidney stone disease; 83.6% were on monotherapy whilst the rest were on combination therapy. Thiazide diuretic was the most common monotherapy agent, followed by alkali citrate therapy and lastly allopurinol. Only 51.1% of patients were adherent to therapy and there were no significant differences between gender and urban / rural status. Adherent patients were likely to be older, less fit, worked part-time jobs and had full medical insurance. Patients who complied with therapy also had significantly lower rates of hospitalisation, emergency department visits and surgery for stone disease. The authors of this study have highlighted the importance of adhering to treatment; however, the issue of how to make patients comply with treatment is yet to be addressed. 

Medication non-adherence and effectiveness of preventive pharmacological therapy for kidney stones.
Dauw CA, Yi Y, Bierlein MK, et al.
JOURNAL OF UROLOGY
2016;195(3):648-52.