[Inappropriate blood levels of digoxin in a study of 2,849 patients from a teaching hospital: the influence of age and sex].
OBJECTIVE
Digoxin is used to treat congestive heart failure and atrial fibrillation. Blood levels need to be monitored to optimize therapeutic performance, detect noncompliance and reduce toxicity. The aim of this study was to evaluate the use of digoxin by measuring blood levels of this drug. The influence of sex and age were also considered.


METHODS
A retrospective study reviewed determinations of blood digoxin concentration in hospitalized and ambulatory patients with congestive heart failure, atrial fibrillation, or both, seen at the University of Granada Teaching Hospital (Spain) from 1992 to 2002. A chi square test was applied to results.


RESULTS
A total of 5,623 laboratory tests for digoxin were done for 2,849 adult patients. Patients whose medical record was incomplete were excluded, and the final sample consisted of 2,629 patients. The 55.4% had inappropriate blood levels of digoxin. Inappropriate concentrations to digoxin were significantly higher in women (p < 0.001). The percentage of patients with high levels of the drug was significantly greater among men (p < 0.001). Very low concentrations (< 0.5 ng/ml) were found in 16% of the patients, with no significant difference between sexes.


CONCLUSIONS
We detect a large percentage of older patients with inappropriate levels of digoxin in blood. Women were more likely than men to have high levels to digoxin in blood. There is evidence that therapeutic monitoring of blood levels of digoxin is not done as often as is advisable; this has implications for the care of patients being treated with this drug.
Puche Cañas
E
E
Unidad de Farmacología Clínica, Hospital Universitario San Cecilio Granada. epuche@ugr.es
Aomar Millán
I
I
Carrillo Santos
J C
JC
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000889:Anti-Arrhythmia Agents / Q000097:blood* / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000097:blood* / Q000188:drug therapy*; D002316:Cardiotonic Agents / Q000097:blood* / Q000627:therapeutic use*; D004077:Digoxin / Q000097:blood* / Q000627:therapeutic use*; D016903:Drug Monitoring; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000188:drug therapy*; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012737:Sex Factors
D000889:Anti-Arrhythmia Agents; D002316:Cardiotonic Agents; D004077:Digoxin