Ana Martin-Suarez1,2, David García González3, Juan F Macías Núñez4,2, Ramón Ardanuy Albajar5, M Victoria Calvo Hernández6,7,8. 1. Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Salamanca, Salamanca, Spain. 2. Instituto de Investigación Biomédica de Salamanca, University Hospital of Salamanca, Salamanca, Spain. 3. Pharmacy Services, University Hospital of Salamanca, Salamanca, Spain. 4. Nefrology Services, University Hospital of Salamanca, Salamanca, Spain. 5. Department of Statistics, Faculty of Sciences, University of Salamanca, Salamanca, Spain. 6. Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Salamanca, Salamanca, Spain. toyi@usal.es. 7. Pharmacy Services, University Hospital of Salamanca, Salamanca, Spain. toyi@usal.es. 8. Instituto de Investigación Biomédica de Salamanca, University Hospital of Salamanca, Salamanca, Spain. toyi@usal.es.
Abstract
BACKGROUND: Digoxin is a frequently prescribed drug in the elderly population. Estimated glomerular filtration rate is widely used to adjust dosages. The HUGE value is a tool for differentiating the presence or absence of chronic kidney disease in elderly patients. We aimed to investigate the usefulness of the HUGE value to predict the initial dose of digoxin in patients aged older than 70 years. METHODS: We reviewed retrospectively the medical records of patients aged older than 70 years with serum digoxin concentrations (SDCs) monitored over a 6-month period (63 patients). A linear regression relating the patient's SDC, maintenance dose of digoxin and the HUGE value was estimated to generate a dosage equation. This equation was validated retrospectively (33 patients) and prospectively (35 patients) in comparison with two existing methods based on creatinine clearance. RESULTS: An equation (HUGE_DIG) was generated to calculate the initial digoxin dose to reach a specific target SDC. Thus, to achieve a SDC of 0.8 ng/mL: Digoxin (mg/day) = 0.091 - 0.006 x HUGE. After retrospective validation, the calculated digoxin doses with this equation were administered in the prospective phase and we did not observe statistical differences between measured and desired SDCs. Moreover, the predictive performance of our equation was better than that obtained with the compared methods. CONCLUSIONS: We offer a new validated digoxin dosing equation for elderly patients. Our results support the need to perform digoxin dosing in elderly people, bearing in mind the changes in renal physiology secondary to ageing and not merely the estimated glomerular filtration rate.
BACKGROUND:Digoxin is a frequently prescribed drug in the elderly population. Estimated glomerular filtration rate is widely used to adjust dosages. The HUGE value is a tool for differentiating the presence or absence of chronic kidney disease in elderly patients. We aimed to investigate the usefulness of the HUGE value to predict the initial dose of digoxin in patients aged older than 70 years. METHODS: We reviewed retrospectively the medical records of patients aged older than 70 years with serum digoxin concentrations (SDCs) monitored over a 6-month period (63 patients). A linear regression relating the patient's SDC, maintenance dose of digoxin and the HUGE value was estimated to generate a dosage equation. This equation was validated retrospectively (33 patients) and prospectively (35 patients) in comparison with two existing methods based on creatinine clearance. RESULTS: An equation (HUGE_DIG) was generated to calculate the initial digoxin dose to reach a specific target SDC. Thus, to achieve a SDC of 0.8 ng/mL: Digoxin (mg/day) = 0.091 - 0.006 x HUGE. After retrospective validation, the calculated digoxin doses with this equation were administered in the prospective phase and we did not observe statistical differences between measured and desired SDCs. Moreover, the predictive performance of our equation was better than that obtained with the compared methods. CONCLUSIONS: We offer a new validated digoxin dosing equation for elderly patients. Our results support the need to perform digoxin dosing in elderly people, bearing in mind the changes in renal physiology secondary to ageing and not merely the estimated glomerular filtration rate.
Authors: Sharon Ann Hunt; William T Abraham; Marshall H Chin; Arthur M Feldman; Gary S Francis; Theodore G Ganiats; Mariell Jessup; Marvin A Konstam; Donna M Mancini; Keith Michl; John A Oates; Peter S Rahko; Marc A Silver; Lynne Warner Stevenson; Clyde W Yancy Journal: J Am Coll Cardiol Date: 2009-04-14 Impact factor: 24.094
Authors: Manuel Heras; María Teresa Guerrero; Angélica Muñoz; Elena Ridruejo; María José Fernández-Reyes Journal: Rev Esp Geriatr Gerontol Date: 2014-11-30
Authors: Michael G Shlipak; Kunihiro Matsushita; Johan Ärnlöv; Lesley A Inker; Ronit Katz; Kevan R Polkinghorne; Dietrich Rothenbacher; Mark J Sarnak; Brad C Astor; Josef Coresh; Andrew S Levey; Ron T Gansevoort Journal: N Engl J Med Date: 2013-09-05 Impact factor: 91.245
Authors: Carlos G Musso; Waldo H Belloso; Paula Scibona; Vincenzo Bellizzi; Juan F Macías Núñez Journal: Postgrad Med Date: 2015-07-09 Impact factor: 3.840
Authors: Carlos G Musso; Hernán Michelángelo; Manuel Vilas; Juliana Reynaldi; Bernardo Martinez; Luis Algranati; Juan F Macías Núñez Journal: Int Urol Nephrol Date: 2008-12-30 Impact factor: 2.370