Renal stone disease in Christchurch, New Zealand. Part 2: a community study on the burden of renal stone disease.

AIM

To quantify the annual burden of a 12-month cohort of newly diagnosed renal stones in the defined community of Christchurch, New Zealand, and to assess this burden by stone size and position.

METHOD

In this prospective study of stone burden, patients in the Christchurch region of New Zealand with newly diagnosed renal stones maintained a weekly diary for a 12-month period to record the utilisation of health services and financial and social costs to families and partners. Patient records were matched with diagnostic and clinical information to provide a comprehensive database. The economic costs of the various services were estimated.

RESULTS

From November 2001 to November 2002, 422 newly diagnosed renal stones were detected--an annual incidence of 105 per 100,000 population. The annual mean cost of these stones was NZ$4274 per person in the first 12 months. The greatest costs were those for emergency visits, hospitalisations and for operative procedures (23.8%, 22.7%, and 21.8% of total financial burden respectively). Patient workdays lost accounted for 10.9% of total costs. Ureteric stones caused greater social burden than kidney stones. Costs were influenced by stone location and size, being significantly higher for ureteric stones and for larger stones.

CONCLUSIONS

Renal stone disease places a considerable burden on the community. The main burdens were related to health service costs, with personal and pharmaceutical costs representing only a small component. The financial burden to society is estimated at $450,000 per 100,000 population ($NZ in 2001/02).