The prevalence of chronic kidney disease in rheumatology outpatients

The introduction of routine reporting of estimated glomerular filtration rate coupled with a new definition of chronic kidney disease (CKD) has led to an unprecedented focus on kidney disease in many patient groups. In light of this, we performed an audit of patients attending the rheumatology clinics to assess the prevalence of CKD in this population.

Over a four week period, we reviewed the renal function of all patients attending the rheumatology clinics and day ward at our hospital (n=351). Renal function was assessed using the 4-variable MDRD formula. We then interviewed those patients with estimated glomerular filtration rate (eGFR) of 59 ml/min or lower.

We found a prevalence rate of 18% for stage 3 CKD or lower in our audit population. Surprisingly, 60.3% of patients in this category were not aware of any problems with their kidneys (n=38).

The prevalence rate of 18% for stage 3 CKD or lower is significantly higher than the five per cent reported within the general population. As a result of this audit, we now plan to ensure that these patients undergo measurement of blood pressure, eGFR, and urinalysis on a six to twelve monthly basis.