Document Type : Original Article

Authors

1 Department of Pharmacy, Section for Social and Clinical Pharmacy, University of Copenhagen, Copenhagen, Denmark

2 Novo Nordisk Foundation Centre for Protein Research, University of Copenhagen, Copenhagen, Denmark

3 Department of Public Health, University of Southern Denmark, Odense, Denmark

4 2 Novo Nordisk Foundation Centre for Protein Research, University of Copenhagen, Copenhagen, Denmark

5 Department of Systems Biology, Centre for Biological Sequence Analysis, Technical University of Denmark, Kongens Lyngby, Denmark

6 Steno Diabetes Center, Gentofte, Denmark

Abstract

Objective: Through manual review of clinical notes for patients with type 2 diabetes 
mellitus attending a Danish diabetes center, the aim of the study was to identify adverse drug 
reactions(ADRs) associated with three classes of glucose‑lowering medicines: “Combinations 
of oral blood‑glucose lowering medicines” (A10BD), “dipeptidyl peptidase‑4 (DDP‑4) 
inhibitors” (A10BH), and “other blood glucose lowering medicines” (A10BX). Specifically, 
we aimed to describe the potential of clinical notes to identify new ADRs and to evaluate 
if sufficient information can be obtained for causality assessment.
Methods: For observed adverse events (AEs) we extracted time to onset, outcome, and 
suspected medicine(s). AEs were assessed according to World Health Organization-Uppsala 
Monitoring Centre causality criteria and analyzed with respect to suspected medicines, type 
of ADR (system organ class), seriousness and labeling status.
Findings: A total of 207 patients were included in the study leading to the identification 
of 163 AEs. 14% were categorized as certain, 60% as probable/likely, and 26% as possible. 
15 (9%) ADRs were unlabeled of which two were serious: peripheral edema associated with 
sitagliptin and stomach ulcer associated with liraglutide. Of the unlabeled ADRs, 13 (87%) 
were associated with “other blood glucose lowering medications,” the remaining 2 (13%) 
with “DDP‑4 inhibitors.”
Conclusion: Clinical notes could potentially reveal unlabeled ADRs associated with 
prescribed medicines and sufficient information is generally available for causality assessment. 
However, manual review of clinical notes is too time-consuming for routine use and hence 
there is a need for developing information technology (IT) tools for automatic screening 
of patient records with the purpose to detect information about potentially serious and 
unlabeled ADRs.

Keywords

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