Fibrates and estimated glomerular filtration rate: observations from an outpatient clinic setting and clinical implications

Background Previous studies have demonstrated that fibrates have an effect on creatinine concentrations. The pattern of change with fibrates in estimated glomerular filtration rate (eGFR), widely used in clinical practice, has not been previously described. Methods Data was retrospectively collected from 132 consecutive case notes of patients started on fibrates in a lipid clinic between 2002 and 2008. Pre- and post-fibrate creatinine concentrations were measured and eGFR measurements were obtained. Results Of the 79 patients with both pre and post-treatment eGFR values <90 ml/min/1.73 m(2), a significant mean eGFR reduction of 8.2 ml/min/1.73 m(2) was noted. Of these patients, 50% demonstrated a reduction in eGFR >8 ml/min/1.73 m(2), 25% demonstrated a reduction >16 ml/min/1.73 m(2), and 10% demonstrated a reduction >21 ml/min/1.73 m(2). Conclusions The authors demonstrate a significant effect of fibrates on eGFR in clinical practice. Awareness of the pattern of eGFR change is important for decisions regarding the continued use of fibrate therapy and/or commonly co-prescribed diabetic drugs and renal specialist referrals.