Importance of creatinine clearance for drug dosing in nursing home residents

Abstract

Serum creatinine is often not an adequate measure of renal function, especially in advanced age or in physically debilitated patients. Estimated creatinine clearance is necessary to decide on usage of drugs such as Metformin. This study included 64 nursing home residents with diabetes treated with Metformin. Creatinine clearance (CrCl) was calculated by the Cockcroft-Gault equation modified for ideal body weight. CrCl more than or equal to 60/mL min was used as a cut-off for appropriate use of Metformin. In our sample, 20.3% had renal failure when measured by serum creatinine while 56.3% had renal failure when measured by CrCl. Age >65 years and women were more likely to be classified as normal for serum creatinine but have abnormal creatinine clearance. Use of estimated creatinine clearance should be advocated instead of serum creatinine when prescribing Metformin, especially for those of older age and among women. © 2014 Informa Healthcare USA, Inc.