Evaluation of Drug-drug Interactions in Cancer Patients Treated at a University Hospital in North Cyprus Using Two Interaction Databases

Abstract

Background: Drug interactions in oncology are of clinical importance owing to the inherent use of multiple medications in cancer treatment which predisposes patients to drug-related problems. Aim: This study aimed to compare two electronic databases based on the frequency, mechanism and severity of drug-drug interactions (DDIs) in cancer treatment at Near East University Hospital. Method: A retrospective observational study of hospitalized cancer patients who had received more than one chemotherapy and/or supportive-care drugs from April 2017 to April 2019. Lexi-interact tool by Lexicomp and Drugs.com databases were used to check (DDIs and all detected interactions were categorized based on the severity-level and mechanism of interaction. Results: A total of 681 prescriptions were evaluated and the median medication per patient was 4 (IQR 3-6). Drugs.com identified potential DDIs in 129 (84.9%) patients while Lexicomp identified potential DDIs in 113 (74.3%) patients. Drugs.com reported DDIs of 394 pairs while Lexicomp reported DDIs of 313 pairs. More than 50% of the potential DDIs were classified as pharmacodynamic interactions in both databases. There were varied reports of severity of potential DDIs, but the test of agreement using kappa index was 0.592 (95% CI: 0.502-0.682, P = 0.0001) and this was interpreted as a moderate agreement between the two databases. Conclusion: Lexicomp documented more detailed information relevant to clinical practice. However, Drugs.com with more sensitivity, detected more potential DDIs. Therefore, we suggest the use of at least two drug databases for quality screening, especially for patients predisposed to polypharmacy.

Potential drug–drug interaction and its determinants among patients with cancer receiving chemotherapy in oncology centres of Northwest Ethiopia: an institutional-based cross-sectional study

“…This study found that nearly half of the mechanisms of PDDIs identified by Drugs.com and Lexicomp Drug Interactions were pharmacokinetic interactions. This finding is consistent with another study in which 50% of interactions were pharmacokinetics,26 43 but opposes a study conducted in Sudan in which the majority of drug interactions were pharmacodynamic interactions 24. This difference may be due to different therapeutic regimens used in different hospitals 50.…”

“…However, studies also reported that major DDIs were frequently identified 39 48. This difference might be due to the use of different drug interaction screening databases, which have different sensitivities,26 49 and the use of different therapeutic regimens in different hospitals 50. The most frequent drug interactions identified by Medscape were significant drug interactions followed by minor interactions, which is in line with a previous study 11 28 41 45.…”

“…As compared with the two databases, Drugs.com identified a relatively higher number of PDDIs. This difference might be due to it being sensitive to detect more PDDIs 26. The present study found that substantial proportion of cancer patients exposed to potenitial drug drug interactions.…”

“…19 Most previous studies related to PDDIs among patients with cancer were limited to other African countries and Western countries. [20][21][22][23][24][25][26] Furthermore, these studies were limited to single DDI screening tools, retrospective methods and small sample sizes. The medication review process in daily practice is not common in Ethiopia due to the lack of clinical pharmacists in the oncology ward which might be one risk factor for PDDIs.…”

“…Most previous studies related to PDDIs among patients with cancer were limited to other African countries and Western countries 20–26. Furthermore, these studies were limited to single DDI screening tools, retrospective methods and small sample sizes.…”