Assessment of medication Dosage Adjustment in Hospitalized Patients with Chronic Kidney Disease

Inappropriate medication dosing can develop adverse drug reactions (ADRs) or ineffective therapy due to declined renal function in patients with renal insufficiency.This necessitates proper renal dose adjustment.Using a retrospective analysis of medical records, this study was proposed to evaluate medication dosage adjustment in hospitalized chronic kidney disease (CKD) patients. This retrospective review of medical records was conducted at the Institute of Kidney Disease (IKD) Peshawar. It included all CKD patients hospitalized between May 01, 2019 and April 25, 2020. Glomerular filtration rate was calculated using Modification of Diet in Renal Disease (MDRD) formula and dose appropriateness was established by evaluating practice with relevant reference books. Of the total 1537 CKD patients, 231(15.03%) had evidence of dosing error, which were considered for final analysis. Overall, 1549 drugs were prescribed, 480(30.99%) drugs required dose adjustment of which 196(40.42%) were adjusted properly and the remaining 286(59.58%) were unadjusted. The most common unadjusted drugs were meropenem, cefepime, ciprofloxacin and rosuvastatin, whereas captopril, aspirin, bisoprolol, pregabalin and levofloxacin had the highest percentage of adjusted drugs. On multivariate logistic regression, the number of drugs requiring dosing adjustments and obstructive nephropathy were found to be statistically significant factors that increased the likelihood of the medication dosing errors, A unit increase in the number of drugs requiring dose adjustment increases 5.241 times the likelihood of dosing error. Similarly the presence of obstructive nephropathy (OR 0.383, 95% Cl [0.153-0.960] P= 0.041) was found to be significantly associated with dosing error after adjustment for potential confounding factors. The dosing of more than half of the prescribed drugs that required adjustment in CKD patients were not adjusted which showed that medication dosing errors were high. This highlights the importance of medication prescription according to guidelines in these patients to improve the outcomes of pharmacotherapy and patients quality of life.