Evaluatıon of Serum Dıgoxın Level ın Dıabetıc Patıents ın a 5 Year Retrospectıve Cohort Study

Abstract

It has been reported that diabetic conditions may alter the expression of P-glycoprotein (P-gp) or its functional activity, and therefore affecting the pharmacokinetic properties of drugs which are P-gp substrates. The aim of this study was to investigate whether the serum level of digoxin, a P-gp subtype, is different in diabetic patients by controlling the effect of other covariate variables. This is a retrospective cohort study evaluating the data measured in the first day of admission to the hospital of patients treated with oral digoxin, who were hospitalized in a university hospital between January 2011 and December 2015. General linear model (GLM) was used for analysis. In this model, digoxin level is dependent variable and diabetes mellitus is fix factor, while age, gender, BUN, creatinine and potassium levels are covariate. P <0.05 was accepted as statistical significant. In this study, total number of hospitalizations was 2974 and DM ratio was 10.7% (n=319). The mean age was 73.1 ± 13.0. The serum digoxin concentration in diabetic patients was calculated as 0.9 ± 0.8 ng/mL (0-4.7ng/mL), and 1.01 ± 1.0 ng/mL (0-15ng/mL) in the non-diabetic patients. In GLM analysis, in the presence of diabetes it was found that digoxin levels decreased significantly (p = 0.016) and other covariate variables such as age, gender, potassium, creatinine and BUN significantly affected the serum digoxin level (P values are p=0.004, p<0.001, p<0.001, p=0.002, p=0.012, respectively). We found that serum digoxin levels decreased in the presence of diabetes. However, further research is needed to determine whether low serum levels of digoxin in diabetic patients are associated with an increase in P-gp expression due to diabetic conditions.